JPH0786169A - Multichamber processing system and cleaning method therefor - Google Patents

Abstract

PURPOSE:To clean the interior of each chamber without causing any damage on the compositional members by providing each processing chamber, carrying chamber, and preliminary chamber with a.gas supply section and a discharge section and feeding ClF3 gas to each gas supply section individually thereby cleaning each chamber. CONSTITUTION:Processing chambers 1, 2, 3 are coupled with three side faces of a first carrying chamber 4, respectively, through gate valves 5, 6, 7. First and second carrying chambers 4, 16 are provided, in the bottom faces thereof with gas supply ports 4A, 25A through which a cleaning gas is fed into the first and second chambers 4, 16 and eventually discharged through gas discharge ports 4B, 25B provided in the bottom faces thereof. After closing the gate valves of all chambers to interrupt them from each other, ClF3 gas is fed individually from a cleaning gas supply system into each chamber thence discharged individually to the outside. The cleaning gas cleans off metallic adherend from the inside of each chamber individually before it is discharged from the chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-chamber processing apparatus and a cleaning method thereof.

[0002]

2. Description of the Related Art Recently, semiconductor integrated circuit devices have been highly integrated, and the degree of integration is from 64 MDRAM to 25.
It is entering the 6MDRAM generation. Therefore, multilayering and miniaturization of the wiring structure have become more remarkable. As the wiring structure becomes multi-layered in this way, the number of steps in the wiring process increases, and the efficiency of the wiring process and dust-proof measures are becoming more problematic than before. Further, as the wiring structure becomes finer, migration disconnection and the like become a problem in the conventional aluminum (Al) wiring, and various metals such as tungsten (W) having excellent migration resistance have been studied as a wiring material instead of Al as a material. ing. Further, as the number of wiring structures increases, various studies are being conducted on the material of the contact holes, via holes and the like. Further, as the diameter of the object to be processed and the number of layers are increased, the coverage of each layer becomes important.

For example, when tungsten is formed as a wiring film, blanket W wiring by the CVD method, which is excellent in coverage, is being studied. This blanket W
Since the wiring film has a drawback that it is easily peeled off and therefore particles are easily generated, a method of providing an adhesion layer such as titanium nitride (TiN) as an underlayer is adopted as a preventive measure. This TiN was conventionally formed by a sputtering method, but the sputtering method has a limit in the coverage at the bottom of the hole having a high aspect ratio.
Also for N, film formation by the CVD method, which is excellent in coverage, is being studied.

For the filling of the contact hole and the via hole, a blanket W or a selection W for selectively filling tungsten by utilizing the chemical properties of the metal film on the surface is being studied. The embedding with the blanket W requires many steps such as formation of an adhesion layer made of TiN, blanket W, and etchback, and the cost is high. Therefore, the wiring of a specific semiconductor integrated circuit element having a high current density can be performed. Tend to apply. On the other hand, the embedding by the selective W does not require an adhesion layer because the hole portion can be selectively embedded, and the multilayer wiring is simple and advantageous in cost. Therefore, select embedding W
The method of using sputtered Al for the wiring has been studied.

Further, as the wiring structure becomes finer, the distance between the wiring layers in the horizontal direction becomes narrower, and a step for filling this gap is also required for each wiring layer, and the wiring becomes finer as the wiring structure becomes finer. More and more processes are required for the process.

In any case, as the semiconductor integrated circuit device becomes multi-layered and finer, the wiring process becomes complicated and more processes are required. And
In these steps, there is an urgent need to develop a processing apparatus having an excellent combination of metal film formation and burying by the CVD method, which is excellent in coverage, or metal film formation by the sputtering method, if necessary. In addition, in the wiring process, it is necessary to increase the throughput of the entire wiring process and to suppress contamination from particles and the like between the processes as much as possible because of the multiple metal film formation and the burying process. 256M DRAM of the future while solving one by one
However, it is necessary to ensure the same quality as that of 64M DRAM or less and to improve the productivity.

A multi-chamber processing apparatus that consistently and continuously processes a plurality of processes has been attracting attention as a powerful processing apparatus that satisfies such requirements. This multi-chamber processing apparatus is an apparatus in which a plurality of film forming processing apparatuses and an embedding processing apparatus are combined to form a module, and a plurality of processing chambers for performing processing such as film forming under a predetermined vacuum, and to these processing chambers. A transfer chamber having a transfer device for transferring the processing object, and a cassette room for loading and unloading the processing object via a vacuum preliminary chamber between the transfer chamber and the transfer chamber are provided. This is a so-called single-wafer processing apparatus configured to perform film forming processing, embedding processing, and the like. In this multi-chamber processing apparatus, after performing film formation processing by CVD or sputtering in each processing chamber, the next chamber is continuously transferred through a transfer device in a transfer chamber maintained at the same degree of vacuum as those processing chambers. Since the film can be transferred to the processing chamber and continuously subjected to film formation processing and a plurality of processing can be efficiently performed, throughput can be increased. Further, since the transfer chamber connecting each processing step is kept in a vacuum, the object to be processed can be transferred in a clean environment, and the object to be processed in each processing step can be maintained as it is. Therefore, the reproducibility of each process can be improved. Furthermore,
This multi-chamber processing apparatus has a high degree of freedom in processing design because the processing chambers can be combined appropriately according to the processing content of the multilayer wiring.

However, from 64M DRAM to 256DRA
When manufacturing a semiconductor integrated circuit device such as M, since the clean room is made super clean, pollution from the clean room is drastically reduced, but the cleanliness inside the processing device is reduced, and 90% of particles are treated. There is a report that it occurs inside the device. In other words, in each processing chamber, not only the object to be processed is deposited along with each film deposition process, but also the susceptor and electrodes that support the object in the processing chamber are deposited at the same time, and further on the peripheral surface of the processing chamber. Is performed,
These will eventually separate and float as particles, or will accumulate on the bottom surface of the processing chamber. Further, in the transfer chamber, particles are generated from the drive unit of the transfer device, and particles are generated and float due to slip of the object to be processed during transfer, and are accumulated on the bottom. Alternatively, the process gas at the time of film formation does not sufficiently react, the products in the process of reaction adhere to the object to be processed, and the products are carried into the carrying chamber or another processing chamber during the carrying process, causing cross contamination. These products will gradually accumulate on the bottom and the like. Then, particles are suspended by the airflow during supply / exhaust during processing or by the airflow generated during driving of the transport system, and these particles contaminate the surface of the object to be processed and reduce the yield.

Therefore, conventionally, in order to eliminate such contamination, the inside of the processing apparatus is cleaned and contaminants such as particles are removed every time the film-forming processing for a predetermined number of times is completed. As the cleaning method,
The method of disassembling the multi-chamber processing device itself and then, after disassembling, immersing each component in a cleaning liquid to clean the contaminants adhering to these components or wiping the contaminants adhering to each component is adopted. It was being done.

[0010]

However, according to the conventional method for cleaning a multi-chamber processing apparatus, after disassembling the multi-chamber processing apparatus, each component is immersed in a cleaning liquid to clean or wipe off each contaminant. Therefore, there is a problem that it takes a lot of time for cleaning and the operation efficiency of the multi-chamber processing apparatus is significantly reduced.

The present invention has been made in order to solve the above-mentioned problems, and is not only plasma-less, but not only inside a plurality of processing chambers, but also inside other chambers such as a transfer chamber without completely damaging the constituent members. An object of the present invention is to provide a cleaning method for a multi-chamber processing apparatus which can be cleaned and which can remove a contamination source such as particles which is a problem when manufacturing a semiconductor integrated circuit element.

[0012]

A multi-chamber processing apparatus according to claim 1 of the present invention comprises a plurality of processing chambers for processing an object, and a transfer chamber for transferring the object to each of these processing chambers. In a multi-chamber processing apparatus including a preliminary chamber connected to the transfer chamber, a gas supply unit and a gas exhaust unit are provided in each of the processing chamber, the transfer chamber and the auxiliary chamber, and cleaning is performed in each of these gas supply units. connect the gas supply system, and separately supplying ClF ₃ gas into each chamber through each of the gas supply unit from the cleaning gas supply system, the ClF ₃ deposits adhering to the inside of each chamber by the gas, respectively It is configured to be individually cleaned.

According to a second aspect of the present invention, there is provided a method for cleaning a multi-chamber processing apparatus, wherein a plurality of processing chambers for processing the object to be processed, a transfer chamber for transferring the object to the processing chambers, and In a method of cleaning the inside of a multi-chamber processing apparatus having a preparatory chamber connected to this transfer chamber, in which each of the above processing chambers, the transfer chamber and the preparatory chamber are individually isolated from each other, ClF ₃
Gas is individually supplied, and the ClF ₃ gas is used to individually clean the deposits adhering to the inside of each chamber.

The cleaning method for a multi-chamber processing apparatus according to a third aspect of the present invention is the method according to the second aspect, wherein ClF ₃ gas is added through an exhaust system pipe provided in each chamber. The air is exhausted from each room.

According to a fourth aspect of the present invention, there is provided a method for cleaning a multi-chamber processing apparatus, wherein at least one film forming chamber for performing a film forming process on an object to be processed, and the object to be processed is transferred to the film forming chamber. In a method for cleaning the inside of a multi-chamber processing apparatus including a transfer chamber provided with a transfer device and a preliminary chamber connected to the transfer chamber, a film is formed on the object to be processed in at least one film forming chamber. After carrying out the treatment and carrying the film-formed object to the outside through the carrying chamber and the preliminary chamber, at least one of the film-forming chamber, the carrying chamber and the preliminary chamber is individually isolated from the others. After that, ClF ₃ gas is individually supplied to each of these chambers, and the deposits adhering to the inside of each chamber are individually cleaned by this ClF ₃ gas.

According to a fifth aspect of the present invention, there is provided a method for cleaning a multi-chamber processing apparatus, wherein at least one film forming chamber for performing a film forming process on an object to be processed, and the object to be processed is transferred to the film forming chamber. In a method for cleaning the inside of a multi-chamber processing apparatus including a transfer chamber provided with a transfer device and a preliminary chamber connected to the transfer chamber, a ClF ₃ gas for cleaning each chamber is provided in each chamber. The respective chambers are individually exhausted via the respective exhaust system pipes.

[0017]

According to the first and second aspects of the present invention, a plurality of chambers such as a processing chamber and a transfer chamber are individually shielded from other chambers, and then each chamber is separated from the other chambers. It is supplied individually ClF ₃ gas from the cleaning gas supply system via the gas supply unit, the ClF ₃ gas reacts with the deposits adhering to the respective chamber, further ClF ₃ gas is activated by the heat of reaction at this time Then, the reaction between the activated ClF ₃ gas and the deposit is promoted, and the deposit adhering to each chamber can be removed.

[0018] According to the invention described in claim 3 of the present invention, in the invention described in claim 2, when evacuating the ClF ₃ gas from the exhaust system pipe provided in the respective chambers, the ClF ₃ gas Reacts with the deposits on the inner surfaces of the respective chambers while passing through the respective exhaust system pipes, so that the deposits on the respective exhaust system pipes can be removed.

According to the fourth aspect of the present invention, the object to be processed is subjected to the film forming process in at least one film forming chamber, and the object to be processed after the film forming is provided in the transfer chamber and the preliminary chamber. After being transported to the outside through the chamber, at least one of the film forming chamber, the transport chamber, and the preliminary chamber is individually shut off from the other, and then ClF ₃ gas is individually supplied to each of these chambers. The ClF ₃ gas reacts with the deposits adhering to the respective chambers, and the heat of reaction at this time further activates the ClF ₃ gas.
Since the reaction between the F ₃ gas and the deposit is promoted, the deposit attached to each chamber can be removed individually.

According to the fifth aspect of the present invention, at least one film forming chamber for performing a film forming process on the object to be processed and a transfer device for transferring the object to the film forming chamber are provided. When cleaning the inside of the multi-chamber processing apparatus including the transfer chamber and the preliminary chamber connected to the transfer chamber, ClF ₃ gas is passed through each exhaust system pipe provided in each of the above chambers. When exhausted individually from the chamber, Cl
The F ₃ gas reacts with the deposits on the inner surfaces of each of the chambers while passing through the exhaust system pipes, so that the deposits on the exhaust system pipes can be removed.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in FIGS. The multi-chamber processing apparatus of this embodiment is configured to supply a cleaning gas from the processing chamber as shown in FIG. 1, for example. That is, a plurality of processing chambers 1 for supplying the cleaning gas, in this embodiment, three processing chambers 1,
2 and 3 are configured to perform a metal film formation process of tungsten or the like under a predetermined vacuum by thermal CVD or the like as described later. And these processing chambers 1,
As shown in the figure, the reference numerals 2 and 3 are connected to three side surfaces of the first transfer chamber 4 formed in a substantially rectangular shape through gate valves 5, 6 and 7, and these gate valves 5 and 6 are connected. , 7 are opened to communicate with the first transfer chamber 4, and closed to shut off the first transfer chamber 4. In addition, each processing chamber 1,
A transfer device 9 for transferring an object to be processed, for example, a semiconductor wafer 8 is provided to the second and third parts, and is configured to be able to maintain the same degree of vacuum as the processing chambers 1, 2, and 3. This transport device 9
The arm 9A is arranged substantially in the center of the first transfer chamber 4 and is configured to be bendable / extendable. The semiconductor wafer 8 is placed on the arm 9A and the semiconductor wafer 8 is transferred. Further, as shown in FIG. 1, a gas supply port 4A is formed as a gas supply unit on the bottom surface of the first transfer chamber 4.
The gas supply port 4A is connected to a cleaning gas supply system 35, which will be described later, which supplies a cleaning gas. Further, the cleaning gas supplied from the gas supply port 4A is configured to be exhausted from a gas exhaust port 4B formed as a gas exhaust unit on the bottom surface of the first transfer chamber 4. In addition, on the remaining one side surface of the first transfer chamber 9, two vacuum preliminary chambers 12 and 1 to be described later are provided via gate valves 10 and 11.
3 are arranged side by side so that they can communicate with each other, and these vacuum prechambers 12 and 13 communicate with the first transfer chamber 4 by opening the gate valves 10 and 11, respectively.
The first transfer chamber 4 can be shut off by closing 0 and 11. Therefore, the semiconductor wafer 8 is transferred from, for example, the vacuum preliminary chamber 12 to a predetermined processing chamber by the carrying / transporting device 9 in a predetermined vacuum atmosphere, and a predetermined film forming process is performed in the processing chamber, and then the processing chamber. Is sequentially transferred to other processing chambers via the transfer device 9 and the predetermined processing is completed in each processing chamber, and then is transferred to another vacuum preliminary chamber 13 again.

These vacuum preparatory chambers 12 and 13 are provided on the side facing the gate valves 10 and 11, respectively.
The second transfer chamber 16 is connected to the second transfer chamber 16 via 4 and 15 so as to communicate with the second transfer chamber 16 by opening these gate valves 14 and 15, and from the second transfer chamber 16 by closing them. It is configured so that it can be shut off. Further, cassette chambers 20 and 21 for accommodating a cassette 19 are communicatively connected to the left and right side surfaces of the second transfer chamber 16 via gate valves 17 and 18, respectively. By opening 14 and 15, it communicates with the second transfer chamber 16, and by closing them, it can be shut off from the second transfer chamber 16. Further, in the second transfer chamber 16, a second transfer device 23 located at the center between the left and right cassette chambers 20 and 21 is arranged.
The semiconductor wafer 8 is transferred between the cassettes 2 and 13 and the cassette chambers 20 and 21. Further, the semiconductor wafer 8 is provided between the second transfer device 23 and the vacuum preliminary chambers 12 and 13.
A positioning device 24 for positioning the semiconductor wafer 8 by the orientation flat of the semiconductor wafer 8 is provided. After the positioning device 24 positions the semiconductor wafer 8 once, the second transfer device 23 transfers the semiconductor wafer 8 to the vacuum preliminary chamber 12. Has been done.

Further, the second transfer chamber 16 is provided with an atmospheric pressure adjusting device (not shown) which supplies an inert gas such as nitrogen gas into the chamber and adjusts the gas pressure to the atmospheric pressure to maintain the atmospheric pressure. In the nitrogen gas adjusted to the atmospheric pressure by the adjusting device, the second transfer device 23 is used to transfer the semiconductor wafer 8 between the cassette 19 in the cassette chambers 20 and 21 and the vacuum preliminary chambers 12 and 13. It is configured. Further, the second transfer chamber 16 is configured so as to be able to maintain a predetermined degree of vacuum during cleaning.

A gas supply port 25A is formed on the bottom surface of the second transfer chamber 16 as a gas supply unit. The gas supply port 25A is supplied to a cleaning gas supply system 35 which supplies a cleaning gas through a pipe 33, for example. It is connected. The cleaning gas supplied from the gas supply port 4A is configured to be exhausted from a gas exhaust port 25B formed as a gas exhaust unit on the bottom surface of the second transfer chamber 16. The gas exhaust port 25B is, for example, the vacuum auxiliary chamber 1
It is connected to the exhaust systems 2 and 13 through a valve (not shown), and is configured to perform vacuum exhaust during cleaning by using this exhaust system. At other times, the valve is closed and the vacuum preliminary chamber 12, Only 13 is evacuated. Then, the processing chambers 1, 2, 3 and the first transfer chamber 4,
Each chamber such as the vacuum preliminary chambers 12 and 13 is provided with an exhaust system so that each chamber can be exhausted. Incidentally, 26 and 27 are gate valves attached to the front surfaces of the cassette chambers 20 and 21.

Next, an embodiment of the cleaning method of the present invention will be described. In this cleaning method, after closing the gate valves of all the chambers of the multi-chamber processing apparatus to shut off the chambers from each other, for example, ClF ₃ gas is individually used as a cleaning gas for each chamber from one cleaning gas supply system described later. To each chamber, and the chamber is individually evacuated to the outside, and during this period, the metal-based deposits that have adhered to the inside of each chamber are individually cleaned with a cleaning gas.
FIG. 2 conceptually shows the flow of the cleaning gas by this cleaning method. That is, the pipe of one cleaning gas supply system 35 is branched corresponding to all the chambers of the multi-chamber processing apparatus, and the branched pipes are individually connected to all the chambers. The cleaning gas is supplied to each of the above. A gas exhaust port is formed in each chamber, and the cleaning gas is exhausted to the outside from each gas exhaust port. Exhaust may be stopped for a predetermined time when the cleaning gas is distributed in each chamber at a predetermined concentration, and the supply of the cleaning gas may be stopped after a predetermined time has elapsed after stopping the exhaust. May be. Further, the exhaust and the supply of the cleaning gas may be repeated in a pulsed manner. The cleaning gas is configured as a gas containing a diluting gas such as ClF ₃ gas or nitrogen gas. This ClF ₃ is chemically active and reacts particularly well with a tungsten-based film, and can effectively remove tungsten-based deposits. However, this ClF ₃ reacts well not only with tungsten but also with other metals such as titanium-based and molybdenum-based metal compounds, and these metal compounds can be effectively removed. At the time of this cleaning, the cleaning atmosphere may be heated and the cleaning gas may be supplied from all the chambers.

[0026] When the cleaning gas is only ClF ₃ gas at a flow rate of ClF ₃ gas of 5 liters / min or less, the temperature of the boiling point to 700 ° C. of ClF _3, the internal pressure 0.1~100Torr It is preferable to carry out cleaning under the conditions of. If the flow rate of ClF ₃ gas exceeds 5 liters / minute, the constituent materials of each chamber may be damaged.
If the temperature of the ClF ₃ gas is below the boiling point, ClF ₃ may condense on the constituent members and damage the material. If the temperature exceeds 700 ° C., the ClF ₃ gas may be activated and damage the material. If the pressure of the ClF ₃ gas is less than 0.1 Torr, the cleaning effect may not be expected, and if it exceeds 100 Torr, the constituent materials may be damaged. Further, the cleaning gas containing ClF ₃ gas as a main component is obtained by diluting ClF ₃ with an inert gas such as nitrogen gas.

Next, the gas supply system for supplying the cleaning gas and the processing devices 1, 2 and 3 will be described with reference to FIG. Here, for example, the processing apparatus 1 is configured as a sputtering apparatus, the processing apparatus 2 is configured as a thermal CVD apparatus, and the processing apparatus 3 is configured as an etching apparatus. Therefore, the processing device 2 will be described as a representative of these processing devices. As shown in FIG. 3, the processing chamber 2 is formed in a cylindrical shape from aluminum or the like that can maintain a predetermined degree of vacuum. Bottom surface 2 in this processing chamber 2
A susceptor 28, on which the semiconductor wafer 8 is mounted, is disposed substantially at the center of A; It is equipped with.
In addition, a quartz window 30 facing the susceptor 28 is formed on the bottom surface of the processing container 28, and a halogen lamp 31 for heating disposed slightly below the quartz window 30 is used for susceptor 28 through the quartz window 30. The upper semiconductor wafer 8 is configured to be heated by light energy.

A process gas supply system 32 for supplying a process gas to the gas dispersion supply unit 29 as shown in FIG.
Are connected via a pipe 33, and a valve 34 attached to the pipe 33 is opened to supply a predetermined process gas into the processing chamber 2 via the gas dispersion supply unit 29. Then, for example, when performing the blanket W process in the processing chamber 2, for example, tungsten hexafluoride (WF ₆ ) and hydrogen are supplied as the process gas from the process gas supply system 32 to the gas dispersion supply unit 29, and the gas dispersion supply is performed. The process gas is evenly supplied to the entire inside of the processing chamber 2 through the dispersion holes 29A, which are formed in a distributed manner on the lower surface of the portion 29. As the process gas for metal wiring, there are a halide, a carbonyl compound, and an organometallic compound, and these are supplied together with the reducing gas. Further, the process gas is preferably a compound having a relatively low vapor pressure as a wiring material.

Further, as shown in FIG. 3, a cleaning gas supply system 35 for supplying a cleaning gas is connected to the pipe 33 through a pipe 36, and during cleaning, the cleaning gas supply system 35 is connected to the pipe 36, the pipe 33 and the gas. The cleaning gas is supplied into the processing chamber 2 via the dispersion supply unit 29. That is, the gas dispersion supply unit 29 also serves as a cleaning gas supply unit for the processing chamber 2. Further, as shown in the figure, this pipe 33 is provided on the upstream side of the processing chamber 2 so that the other processing chambers 1,
3, the first transfer chamber 4, the vacuum preliminary chambers 12, 13 and the second transfer chamber 16 are branched so as to be able to supply the cleaning gas,
The downstream ends of the branched pipes 33 are respectively connected to the gas supply ports of these chambers so that the cleaning gas can be individually supplied to all the chambers. The cleaning gas supply system 35 includes a ClF ₃ gas cylinder 37 for storing the ClF ₃ gas as a cleaning gas, a nitrogen gas cylinder 38 which stores nitrogen gas for diluting the ClF ₃ gas, respectively both of them 37 and 38 pipe Pipes 36 </ b> A and 36 </ b> B branched from 36 are respectively connected to the ends. A valve 39, a mass flow controller 40, and a valve 41 are sequentially arranged from upstream to downstream in a pipe 36A to which a ClF ₃ gas cylinder 37 is connected,
Further, a valve 42, a mass flow controller 43, and a valve 44 are sequentially arranged from upstream to downstream in a pipe 36B to which the nitrogen gas cylinder 37 is connected.
Gases from 38 join together in the pipe 36, and by opening the valve 45, the respective processing chambers 1, 2, 3,
First transfer chamber 4, vacuum preliminary chambers 12 and 13, and second transfer chamber 1
The cleaning gas can be supplied into the cleaning chamber 6.

An exhaust port 46 located near the susceptor 28 is formed on the bottom surface 2A of the processing chamber 2. Then, the vacuum exhaust pump 4 is connected to the exhaust port 46 via an exhaust pipe 48.
9 is connected to the processing chamber 2 by this vacuum exhaust pump 49.
The inside is evacuated to maintain a predetermined degree of vacuum. The vacuum exhaust pump 49 can also be used for exhausting the cleaning gas when the cleaning method of the present invention is performed. Therefore, the exhaust port 46 also serves as an exhaust unit for the cleaning gas in the processing chamber 2. As the vacuum pump 49, it is preferable to use an oil-free dry pump so as not to be affected by the exhausted gas. Furthermore, this vacuum exhaust pump 49
A detoxifying device 50 that captures harmful gases such as process gas and cleaning gas exhausted from the vacuum exhaust pump 49 and removes these harmful gases from the exhaust gas is disposed on the downstream side of the exhaust gas. ClF is used for this abatement device 50.
A solvent in which ₃ is well dissolved, for example, one filled with an alkaline solution is used.

Further, the vacuum preparatory chambers 12 and 13 connected to the front of the processing apparatuses 1, 2 and 3 through the first transfer chamber 4, that is, the lower side of the paper in FIG. 1, are shown in FIG. It is configured as shown. As shown in the figure, the vacuum prechamber 12 includes a prechamber body 51 made of the same material as the processing chamber, and a cooling stage 52 arranged in the prechamber body 51 for cooling the semiconductor wafer. A heating device 53 arranged to face the cooling stage 52 and above the top surface of the preparatory chamber main body 51 for preheating the semiconductor wafer; and a vertical device for supporting the semiconductor wafer between the heating device 53 and the cooling stage 52. The two-stage support members 54, 55, the support members 54, 55 are integrally connected to each other, and the connection shaft 56 penetrating the bottom surface of the preliminary chamber body 51 is connected to the lower end of the connection shaft 56. An elevating mechanism 57 that elevates and lowers 54 and 55 is provided. An exhaust port 51A is formed on the bottom surface of the preliminary chamber body 51, and a vacuum exhaust pump 59 is connected to the exhaust port 51A via an exhaust pipe 58. The vacuum exhaust pump 59 evacuates the inside of the preliminary chamber body 51. Is configured to. This vacuum pump 59
Can also be used when carrying out the cleaning method of the present invention. A gas supply port 51B is formed near the exhaust port 51A, and a gas supply source (not shown) is connected to the gas supply port 51B via a supply pipe 60.
An inert gas or the like is supplied into the auxiliary main body 51 in a vacuum state to return the inside pressure to the atmospheric pressure. Further, the supply pipe 60 is provided with the pipe 3 of the cleaning gas supply system 35.
3 is connected, and the cleaning gas can be supplied into the vacuum preliminary chamber 12 through the pipe 33 and the supply pipe 60.

The heating device 53 has a heating lamp 53A such as a halogen lamp and a reflecting plate 53B for reflecting the light of the heating lamp 53A toward the auxiliary chamber body 51 side.
The light energy from the heating lamp 53A reflected by the reflecting plate 53B is irradiated through a quartz window 53C provided on the top surface of the auxiliary chamber main body 51 to heat the semiconductor wafer therein. There is. That is, the semiconductor wafer is preheated before being loaded into the processing chamber. At this time,
The supporting mechanism 54 is raised by the elevating mechanism 57 to approach the heating device 53 to preheat the unprocessed semiconductor wafer. When the processed semiconductor wafer is unloaded, the semiconductor wafer is cooled according to the external temperature. At this time, the elevating mechanism 57 lowers the support 55 to bring it into contact with the cooling stage 52. Cooling the semiconductor wafer. As shown in FIG. 4B, the support members 54 and 55 have rings 54A and 55A formed to have a diameter slightly larger than the outer diameter of the cooling stage 52, and the rings 54A and 55, respectively.
Three holding claws 54B attached to A at equal intervals in the circumferential direction,
55B, and these holding claws 54B, 55
B is configured to support the semiconductor wafer. In addition, the other vacuum preliminary chambers 13 are also similar to the vacuum preliminary chambers 12, the preliminary chamber body 61, the cooling stage 62, the heating device 63, the support tools 64 and 65, the connecting shaft 66, the lifting mechanism 67, the exhaust pipe 68.
And a supply pipe 70. And the vacuum reserve chamber 1
Similarly to the case of 2, the supply pipe 70 is connected to the pipe 33 of the cleaning gas supply system 35.
The cleaning gas can be supplied into the vacuum auxiliary chamber 13 via the supply pipe 70. The exhaust ports and the gas supply ports of the vacuum auxiliary chambers 12 and 13 also serve as an exhaust part and a supply part of the cleaning gas.

The second transfer device 2 disposed in the second transfer chamber 16 connected to the front of the vacuum preliminary chambers 12 and 13.
The reference numeral 3 designates an arm 71 that can be bent and extended by a link mechanism, and a hand 72 connected to the tip of this arm 71.
And a vacuum exhaust pump (not shown) for exhausting the semiconductor wafer 8 through a vacuum exhaust pipe 74 so that the semiconductor wafer 8 is vacuum-sucked by a hole 73 formed in the upper surface of the hand 72. When the semiconductor wafer 8 is transferred in a chamber where the pressure is maintained at atmospheric pressure or higher, the first transfer device 23 extends the arm 71 and inserts the arm 71 between the semiconductor wafers 8 in the cassette 19, Semiconductor wafer 8 on hand 72
And the semiconductor wafer 8 is accurately adsorbed and fixed through the hole 73 of the hand 72 by the vacuum exhaust pump to evacuate it through the vacuum exhaust pipe 74, and the semiconductor wafer 8 is transported without falling off. The suction is released and the semiconductor wafer 8 is accurately placed at a predetermined position.

As shown in FIG. 2, the gas exhaust port 4B of the first transfer chamber 4 and the gas exhaust port 25B of the second transfer chamber 16 are connected to the vacuum exhaust pumps 59 of the vacuum prechambers 12 and 13 by a pipe 75, for example. The vacuum exhaust pump 59 is configured to exhaust the cleaning gas in the transfer chambers 4 and 16 via the pipe 75. Although not shown, the pipe 75 is connected to the abatement device 50, and the abatement device 50 removes harmful components in the exhaust gas and then exhausts the exhaust gas to the outside.

Next, an example of a wiring film forming process using the above multi-chamber processing apparatus will be described. For example,
In the processing chamber 1, TiN is formed on the surface of the contact hole of the semiconductor wafer by sputtering in the processing chamber 1, and in the processing chamber 2, tungsten is embedded in the contact hole of the processed semiconductor wafer in the processing chamber 1 by the blanket W to perform processing. In the chamber 3, a process of etching back the tungsten from the surface of the semiconductor wafer in which tungsten is embedded in the process chamber 2 and leaving the tungsten only in the contact holes is performed. These series of wiring processes are performed at the same time, and after the process in each processing chamber, the semiconductor wafer is continuously transferred to the next process through the first transfer device 9. Of course, each of the processing chambers is maintained at the degree of vacuum required for each processing.

For example, the blanket W in the processing chamber 2 will be described. When the process gas supply system 32 supplies tungsten hexafluoride (WF ₆ ) and hydrogen as the process gas to the gas dispersion supply unit 29, the lower surface of the gas dispersion supply unit 29 will be described. The process gas is evenly supplied to the entire room through the dispersion holes 29A. At this time, the light energy of the halogen lamp 31 is applied to the susceptor 28 through the quartz window 30 and the semiconductor wafer 8 supported by the susceptor 28 is heated to a predetermined temperature, and the heated semiconductor wafer 8 is brought into contact with the process gas. Then, WF ₆ is hydrogen-reduced by the thermal energy and a tungsten film is formed on the front surface of the semiconductor wafer 8. By this treatment, the tungsten film is formed not only on the surface of the semiconductor wafer 8 but also on other portions such as the susceptor 28.

When the film forming process of the blanket W is completed, the respective processes are completed also in the other process chambers 1 and 3, and the semiconductor wafer 8 is transferred from each process chamber to the next process in the first transfer chamber 4. It is transported by the first transport device 9. That is,
When each semiconductor wafer 8 is transferred, the gate valves 5, 6 and 7 of each processing chamber are opened and the gate valves 10 and 11 of the vacuum preliminary chambers 12 and 13 are sequentially opened to connect these chambers to each other. In this state, the first transfer device 9 is driven to transfer the semiconductor wafer 8 in the processing chamber 3 into the vacuum preliminary chamber 13, and the semiconductor wafer 8 is transferred to the support 55 inside the vacuum preliminary chamber 13. Then, the arm 9A of the first transfer device 9 is retracted from the vacuum preliminary chamber 13, and the arm 9A is continuously moved into the processing chamber 2.
A is extended, and the semiconductor wafer 8 after the blanket W on the susceptor 28 is taken out and transferred to the processing chamber 3. Further, the arm 9A is extended into the processing chamber 1, the semiconductor wafer 8 after the TiN film is formed is taken out from the inside, and the semiconductor wafer 8 is transferred to the susceptor 28 in the processing chamber 2. After that, the arm 9A is extended into the vacuum preliminary chamber 2, the semiconductor wafer 8 preheated by the heating device 53 is taken out from the support tool 54, and the semiconductor wafer 8 is transferred into the processing chamber 1. When these series of continuous operations are completed in succession, the respective gate valves are sequentially closed to prepare for the next operation.

In the vacuum preliminary chamber 12, when the gate valve 10 is closed, the gate valve 14 is then opened to receive the next semiconductor wafer 8 positioned by the second transfer device 23 by the support 55. Then, the elevating mechanism 57 is driven to move the support tool 55 through the connecting shaft 56 to move the support chamber 55
Move closer to the top surface of 1. At this time, in the spare chamber main body 51, the vacuum exhaust pump 59 is driven to control the pressure in the chamber to the first transfer chamber 4
The semiconductor wafer 8 is preheated by the heating device 53 in preparation for the next process while being evacuated to the same level as the vacuum degree. On the other hand, the vacuum auxiliary chamber 13 with the gate valve 11 closed
Then, nitrogen gas is supplied from the gas supply pipe 70 into the auxiliary chamber main body 61 to return the internal pressure to the atmospheric pressure level, and the lifting mechanism 67 is driven to move the support tool 64 to the cooling stage 62 via the connecting shaft 66. The semiconductor wafer 8 is contacted and cooled to room temperature. After cooling, the gate valve is opened to communicate with the second transfer chamber 16 adjusted to the atmospheric pressure by nitrogen gas, and the semiconductor wafer 8 on the support 65 is transferred to the cassette 19 in the cassette chamber 21 by the second transfer device 23. To do. At this time, the second
Since the carrier device 23 vacuum-sucks the semiconductor wafer 8 through the hole 73 of the hand 72, the semiconductor wafer 8 can be transferred without being missed. This completes a series of processes in the multi-chamber processing apparatus. These series of processing steps are performed for all the semiconductor wafers 8 housed in the cassette 19, and then replaced with unprocessed semiconductor wafers 8.

By the film forming process as described above, the processing apparatus 1,
Within 2 and 3, some coatings are formed on the respective wall surfaces, the susceptor 28 and other portions, and when the film forming process is repeated a predetermined number of times, the coatings are laminated each time, and eventually these are separated and become particles as particles. As described above, the particles are suspended and the clean semiconductor wafer 8 is contaminated. Further, reaction products and decomposition products that cannot be completely reacted in the processing chambers 1, 2, and 3 adhere to the semiconductor wafer 8.
Therefore, these reaction products and decomposition products are scattered from the semiconductor wafer 8 during the process of transferring the semiconductor wafer 8, and not only the processing chambers 1, 2 and 3, but also the other first transfer chamber 4, the vacuum preliminary chamber 12, 13 and the second transfer chamber 16 are also scattered and gradually accumulated at the bottom of each chamber. Then, these may also become particles and contaminate the semiconductor wafer 8. Furthermore, in the first and second transfer chambers 4 and 16, particles are generated from the drive parts of the transfer devices 9 and 23, and these particles gradually accumulate on the bottom surfaces of the transfer devices 9 and 23. There is a risk that the semiconductor wafer 8 will fly up and be contaminated.

Therefore, after the film forming process is performed a predetermined number of times, the process is once interrupted and dust such as particles is removed by the cleaning method of the present invention. To this end, first, after turning off the halogen lamp 31 and the like in the processing chamber 2, the semiconductor wafers 8 are not in the processing chambers 1, 2, and 3. Next, after closing the gate valves of all the chambers of the multi-chamber processing apparatus to shut off each chamber from each other, the cleaning gas supply system 35 uses ClF ₃ gas which may contain a diluting gas as a cleaning gas. As shown by 2, the cleaning of this embodiment is carried out by supplying each chamber individually. At the time of this cleaning, it is preferable to replace the inside of each chamber with nitrogen gas or the like in advance.

Next, the vacuum exhaust pumps 49 and the like in the processing chambers 1, 2 and 3 and the vacuum exhaust pumps 59 in the vacuum preliminary chambers 12 and 13 are driven at room temperature higher than the boiling point of ClF ₃ to drive the respective processing chambers 1 and 2. 3, the nitrogen gas is exhausted from the first transfer chamber 4, the preliminary vacuum chambers 12 and 13, and the second transfer chamber 16 to maintain the degree of vacuum in each chamber at a predetermined value. Then, under this exhaust state, the valves 39, 41 of the cleaning gas supply system 35,
45 is opened at a predetermined opening, and the mass flow controller 40 causes the pipe 33 to flow ClF ₃ gas in each chamber at a predetermined flow rate, for example, 5 liters / minute or less.
Supply through. Processing chamber 2 connected to this pipe 33
Gas dispersion supply unit 29, other gas supply ports of the processing chambers 1 and 3, the gas supply port 4A of the first transfer chamber 4, each vacuum preliminary chamber 1
2, 13 gas supply ports 51B and 61B and the second transfer chamber 1
The cleaning gas is individually introduced into each chamber from the gas supply port 25A of No. 6 and Cl in each chamber is introduced.
The pressure of F ₃ gas is maintained at 0.1 to 100 Torr. At this time, the cleaning gas is the exhaust port 46 of the processing chamber 2, the exhaust ports (not shown) of the other processing chambers, the gas exhaust port 4B of the first transfer chamber 4, the exhaust ports 51A of the vacuum preliminary chambers 12 and 13, 6
Since the cleaning gas consumed by the cleaning from 1A and the gas exhaust port 25B of the second transfer chamber 16 is constantly exhausted to the vacuum exhaust pumps 49, 59 and the like, the cleaning gas is updated.
Adjust the cleaning gas pressure in each chamber to 0.1-1
Each chamber can be efficiently cleaned individually with the fresh cleaning gas maintained at 00 Torr and updated.

Since the ClF ₃ gas supplied to each chamber is a chemically active gas, the tungsten-based coatings formed in the processing chambers 1, 2 and 3 and these processing chambers 1,
It is possible to cleanly clean each chamber by reacting with the deposits deposited on the bottom surfaces of 2, 3 and all other chambers in the process, and removing these coatings and deposits individually in each chamber. it can. Also, ClF ₃
Since the reaction of the gas with the coating film and the like is exothermic, the reaction of ClF ₃ gas is further promoted by this heat generation, and the deposit such as the coating film can be further removed. In particular, since ClF ₃ gas reacts well with tungsten, the tungsten-based deposits deposited in each chamber can be cleaned well in this embodiment.

In addition, in this embodiment, since the cleaning gas is exhausted to the outside through the exhaust system pipes, the reaction is performed like the exhaust pipes of the respective exhaust pipes, particularly the processing chambers 1, 2, and 3. The film can be removed by a cleaning gas even in a portion where the film of the product is easily formed. Further, since the poisonous gas discharged from the exhaust system can be removed by the detoxifying device 50, clean exhaust can be performed.

As described above, according to this embodiment, N
Even in areas where plasma cannot be removed by the method of cleaning the inside by using plasma such as F ₃ gas, ClF ₃ gas is completely spread in each chamber individually and even in the area where plasma does not reach. Everything can be completely cleaned. From this, 6
It is possible to completely clean all the chambers that make up the multi-chamber processing apparatus, which can be the mainstream of the manufacturing apparatus for semiconductor integrated circuit devices composed of multi-layer wiring of 4 MDRAM or more, It can remove polluting sources such as particles. Moreover, according to this embodiment, ClF
_{Even though the 3} gases are active gases, they are not corrosive to materials and are plasma-less, so extremely gentle cleaning can be performed without damaging the inside of the device due to plasma. Further, according to the present embodiment, since the existing multi-chamber processing apparatus is provided with the cleaning gas supply system 35 as a cleaning system and only a slight modification of the exhaust system is required, effective cleaning can be performed at an extremely low cost. be able to. Further, as a matter of course, the cleaning time can be remarkably shortened as compared with the method in which the worker dismantles the apparatus and cleans it.

As another cleaning method, C
There is also a method of cleaning the inside of the processing apparatus using the plasma of 1F ₃ gas. In this cleaning method, Cl
For example, F ₃ gas is individually supplied into the processing chambers 1 and 2 which are film forming chambers and the processing chamber 3 which is an etching chamber, and plasma of ClF ₃ gas is generated in these processing chambers 1, 2 and ₃ , respectively. The plasma is used to individually clean the susceptor (not shown), the electrodes and the vicinity thereof in each of the processing chambers 1, 2 and 3, and the ClF ₃ gas is used for the other first transfer chamber 4, the preliminary vacuum chambers 12, 13 and By supplying the two transfer chambers 16 simultaneously and individually, all the chambers of the multi-chamber processing apparatus can be individually cleaned. According to this method, the inner surface, susceptor, and electrode of each of the processing chambers 1 and 2 are formed by the film forming process,
Alternatively, even if the inner surface, the susceptor, and the electrode are formed by the etching back process in the processing chamber 3, the deposited film can be effectively removed by the active species in the plasma of ClF _{3 on} the susceptor and the electrode, and All chambers can be cleaned with ClF ₃ gas in the same manner as described above. Even in this case, the cleaning gas such as ClF ₃ gas can be turned into plasma in the processing chamber 2 without removing the apparatus, and the film formed on the susceptor, the electrode, etc. or the adhered particles can be removed by etching. In addition, the cleaning time can be shortened, and moreover, the cleaning can be simply performed in the operating state.

In the above embodiment, the case where ClF ₃ gas is used as the cleaning gas has been described, but in the present invention, nitrogen gas is appropriately used according to the component of the deposit such as the coating film from which the ClF ₃ gas is to be removed. The activity can be adjusted by diluting it. Further, in this embodiment, the cleaning gas is supplied individually from one cleaning gas supply system 35 to each chamber, but the cleaning gas supply system is individually attached to each chamber. May be.
Further, in the above-mentioned embodiment, in the chambers other than the processing chamber, the gas supply port and the gas exhaust port of the cleaning gas are provided on the respective bottom surfaces, but the places and the number of these are appropriately set as necessary. You can
Further, the cleaning of the cassette chambers 20 and 21 was not described in the above-mentioned embodiment, but in the case of these chambers, the operator can easily clean the inside with the gate valves 26 and 27 open. It goes without saying that the cleaning method of the present invention is used. If the cleaning method of the present invention is applied to the cleaning of the cassette chambers 20 and 21, respectively, as described above,
1 may be provided with a cleaning gas supply port and an exhaust port.

[0047]

As described above, according to the invention described in claim 1 of the present invention, after a plurality of chambers of a multi-chamber processing apparatus are individually shut off from each other, ClF ₃ gas is supplied to each chamber. Are individually supplied from the cleaning gas supply system, and the deposits adhering to the insides of the chambers are individually cleaned by the ClF ₃ gas. A multi-chamber processing apparatus capable of completely cleaning the inside of other chambers, such as the above, individually without damaging the respective constituent members, and removing contamination sources such as particles, which are a problem when manufacturing a semiconductor integrated circuit device, and its cleaning. A method can be provided.

According to the second aspect of the present invention, after the plurality of chambers of the multi-chamber processing apparatus are individually shut off from each other, ClF ₃ gas is individually supplied to each chamber. Since the ClF ₃ gas is used to individually clean the deposits adhering to the inside of each chamber, not only the insides of a plurality of processing chambers but also the insides of other chambers such as a transfer chamber are individually plasmaless. It is possible to provide a multi-chamber processing apparatus capable of completely cleaning the respective constituent members without damaging them, and capable of removing a contamination source such as particles, which is a problem at the time of manufacturing a semiconductor integrated circuit element, and a cleaning method thereof.

Further, according to the invention described in claim 3 of the present invention, in the invention described in claim 2, the ClF ₃ gas is exhausted from each chamber through the exhaust system piping of each chamber. It is possible to provide a cleaning method for a multi-chamber processing apparatus that can individually remove deposits attached to the inner surface of an exhaust system pipe such as each processing chamber by using ClF ₃ gas.

According to the fourth aspect of the present invention, the object to be processed is subjected to the film forming process in at least one film forming chamber, and the object to be processed after the film forming is transferred to the transfer chamber and the preliminary chamber. After being transported to the outside of the apparatus through the chamber, at least one film forming chamber, the transport chamber, and the preliminary chamber are individually isolated from each other, and then ClF ₃ gas is individually supplied to each of these chambers. Since ClF ₃ gas is used to individually clean the deposits adhering to the inside of each chamber, not only the inside of at least one film-forming chamber without plasma, but also the inside of other chambers such as the transfer chamber. A multi-chamber processing apparatus that can completely clean individual constituent members without damaging them and can remove contaminant sources such as particles, which is a problem when manufacturing semiconductor integrated circuit elements. A cleaning method can be provided.

According to the fifth aspect of the present invention, since the ClF ₃ gas is individually exhausted from each chamber through each exhaust system pipe provided in each chamber, at least It is possible to provide a cleaning method for a multi-chamber processing apparatus which can individually remove deposits attached to the inner surface of an exhaust system pipe provided in one of the film forming chamber and other chambers by ClF ₃ gas.

[Brief description of drawings]

FIG. 1 is a plan view showing an entire embodiment of a multi-chamber processing apparatus of the present invention.

FIG. 2 is an explanatory view conceptually explaining the flow of cleaning gas in one embodiment of the cleaning method of the present invention.

3 is a configuration diagram showing a processing chamber and a cleaning gas supply system of the multi-chamber processing apparatus shown in FIG.

4A and 4B are diagrams showing a vacuum preparatory chamber of the multi-chamber processing apparatus shown in FIG. 1, in which FIG. 4A is a sectional view thereof and FIG.
FIG. 6 is a perspective view showing a support tool for supporting a semiconductor wafer in a vacuum preliminary chamber taken out.

5A and 5B are diagrams showing a main part of the second transfer device shown in FIG. 1, in which FIG. 5A is a plan view thereof and FIG. 5B is a side view thereof.

[Explanation of symbols]

1, 2 and 3 processing chamber (chamber) 4 first transfer chamber (chamber) 4A cleaning gas supply port (gas supply part) 4B cleaning gas exhaust port (gas exhaust part) 8 semiconductor wafer (processing target) 9 Transport Device 12, 13 Vacuum Reserve Chamber (Chamber) 16 Second Transport Chamber (Chamber) 23 Second Transport Device 25A Cleaning Gas Gas Supply Port (Gas Supply Section) 25B Cleaning Gas Gas Exhaust Port (Gas Exhaust Section)

Claims (5)

[Claims] 1. A multi-chamber processing apparatus comprising a plurality of processing chambers for processing an object to be processed, a transfer chamber for transferring the object to be processed to each of these processing chambers, and a preparatory chamber connected to the transfer chamber. A gas supply unit and a gas exhaust unit are respectively provided in the processing chambers, the transfer chambers, and the auxiliary chambers, and a cleaning gas supply system is connected to each of the gas supply units, and the gas supply units are connected from the cleaning gas supply system. A multi-chamber processing apparatus, characterized in that ClF ₃ gas is individually supplied to each of the chambers via the above, and deposits attached to the inside of each chamber are individually cleaned by the ClF ₃ gas. 2. A multi-chamber processing apparatus comprising: a plurality of processing chambers for processing an object to be processed; a transfer chamber for transferring the object to be processed to each of these processing chambers; and a preparatory chamber connected to the transfer chamber. In the method of cleaning the inside, after individually shutting off the processing chambers, the transfer chambers, and the auxiliary chambers from each other, ClF ₃ gas is individually supplied to each chamber, and the inside of each chamber is supplied by this ClF ₃ gas. A method for cleaning a multi-chamber processing apparatus, characterized in that the adhered matter adhered to the substrate is individually cleaned. 3. The method for cleaning a multi-chamber processing apparatus according to claim 2, wherein ClF ₃ gas is exhausted from each chamber through an exhaust system pipe provided in each chamber. 4. A at least one film forming chamber for performing a film forming process on an object to be processed, a transfer chamber provided with a transfer device for transferring the object to the film forming chamber, and a spare connected to the transfer chamber. In a method for cleaning the inside of a multi-chamber processing apparatus including a chamber, a film forming process is performed on the object to be processed in at least one of the film forming chambers, and the object to be processed after film formation is transferred to the transfer chamber and the chamber. After being transported to the outside through the preliminary chamber, at least one of the film forming chamber, the transport chamber and the preliminary chamber are individually isolated from each other, and then ClF ₃ gas is individually supplied to each of these chambers, A method for cleaning a multi-chamber processing apparatus, characterized in that deposits attached to the inside of each chamber are individually cleaned with this ClF ₃ gas. 5. At least one film forming chamber for performing a film forming process on an object to be processed, a transfer chamber provided with a transfer device for transferring the object to the film forming chamber, and a spare connected to the transfer chamber. A method for cleaning the inside of a multi-chamber processing apparatus including chambers, wherein C
A method for cleaning a multi-chamber processing apparatus, characterized in that the 1F ₃ gas is individually exhausted from each chamber through each exhaust system pipe provided in each chamber.