JP3305215B2 - Gas treatment method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas processing method and apparatus for performing gas processing such as adhesion processing on an object to be processed such as a semiconductor wafer or an LCD substrate.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process,
A processing liquid, for example, a photoresist liquid is applied to a semiconductor wafer typified by a silicon substrate, a circuit pattern is reduced by using a photolithography technique, the photoresist film is exposed, and a series of processings for developing the same are performed. There is a step of applying.

A processing system for performing such coating / developing includes a cassette station for unloading a semiconductor wafer as an object to be processed from a cassette and loading the semiconductor wafer into the cassette, a cleaning unit for cleaning the wafer, and a process for making the surface of the wafer hydrophobic. Unit for cooling, a cooling unit for cooling the wafer to a predetermined temperature, a resist coating unit for coating the surface of the wafer with a resist solution, and baking for pre-baking or post-baking for heating the wafer before and after applying the resist solution. A unit, a peripheral exposure unit for removing the resist on the peripheral portion of the wafer, a wafer delivery table for delivering the wafer between adjacent exposure apparatuses, and exposing the exposed wafer to a developing solution. A developing unit for selectively dissolving the exposed or unexposed portions of the resist in a developing solution; Has a consolidation with the structures in the body,
This is intended to improve work.

In the adhesion processing performed in such a processing system, HMDS gas is supplied to a semiconductor wafer disposed horizontally in a processing chamber, and heat treatment is performed to make the surface of the hydrophilic semiconductor wafer hydrophobic. Specifically, it is possible to chemically separate the OH group bond on the base of the oxide film substrate and remove moisture.

In this process, first, a semiconductor wafer is mounted on a mounting table, and the inside of the processing chamber is evacuated. Next, HMDS gas is introduced into the processing chamber to apply HMDS to the semiconductor wafer. After this process is completed, HMDS is forcibly exhausted by an exhaust mechanism so as to prevent the HMDS atmosphere from being released into the atmosphere, and a replacement gas such as N ₂ gas is introduced into the processing chamber. Purge.

[0006]

However, when such an adhesion process is performed, the replacement gas is supplied at a relatively large flow rate.
Particles may be generated, and the particles may adhere to the semiconductor wafer to be processed.

Further, after the semiconductor wafer is placed on the mounting table, it is positioned by a positioning member disposed therearound. Therefore, the flow of the HMDS gas, which is the processing gas, is uneven depending on the way of exhaust. And it may not be possible to perform uniform processing.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a gas processing method and apparatus capable of performing good gas processing without causing particles to adhere or uneven processing. Aim.

[0009]

In order to solve the above problems SUMMARY OF THE INVENTION The first invention is in central portion of the specimen in the process chamber, a first gas supplying vertical processing gas to the object to be processed Channel
Supplying a processing gas through the gas processing, and after the gas processing is completed, the first gas flow path
Gas at an oblique angle inclined radially with respect to one gas flow path
A step of switching the second gas flow channel for supplying, through said second gas passage to the object to be processed in the processing chamber
And supplying a replacement gas, and, when supplying the processing gas and supplying the replacement gas, exhausting the processing chamber. provide.

In a second aspect , a processing chamber and a processing target in the processing chamber are provided.
A support mechanism for horizontally supporting the body, and a processing target in the processing chamber.
Supply either process gas or replacement gas to the body
Gas supply unit, and an exhaust mechanism for exhausting the inside of the processing chamber.
The gas supply unit is configured to process the object supported by the support mechanism.
A first process gas is supplied vertically toward the center of the body.
A gas flow path, radially inclined with respect to the first gas flow path;
Placed on the object supported by the support mechanism at an oblique angle.
A second gas flow path for supplying the exchange gas,
Disconnects the first gas flow path and the second gas flow path accordingly.
Gas having a switching mechanism for switching
A processing device is provided.

According to a third aspect of the present invention, there is provided a processing chamber and a processing target in the processing chamber.
A support mechanism for supporting the body horizontally, and an upper part of the processing chamber.
Fixed and detachable plate,
The processing chamber is provided with a processing target for the object to be processed in the processing chamber.
Gas supply unit that supplies either gas or replacement gas
Any one of the processing gas and the replacement gas in the gas supply unit.
A gas supply pipe for guiding the
Process gas and replacement gas selectively
A valve for switching to flow through the gas supply pipe;
A gas processing apparatus having an exhaust mechanism for exhausting the inside of the processing chamber.
A gas processing method for performing gas processing by means of
Is set to the processing gas side, and provided in the gas supply unit.
And facing the center of the object to be processed supported by the support mechanism.
Through a first gas flow path for supplying a processing gas vertically.
Supplying gas and performing gas treatment; and gas treatment.
After completion, the gas flow path is switched to the first gas flow path by the switching mechanism.
From the first gas flow provided in the gas supply unit.
At the support mechanism at an oblique angle radially inclined to the road
Second gas flow for supplying a replacement gas to a supported object to be processed
And switching the valve to the replacement gas side
Then, the second gas is applied to the object to be processed in the processing chamber.
Supplying a replacement gas through a gas flow path;
Before supplying the replacement gas and when supplying the replacement gas,
Exhausting the processing chamber by an exhaust mechanism.
The present invention provides a gas treatment method characterized in that:

[0012] Oite the present invention, the central portion of the specimen,
First gas supplying vertical processing gas to the object to be processed
By supplying the processing gas through the flow path, the processing gas can be uniformly supplied from the center of the object to be processed toward the periphery, and uniform gas processing is realized. In addition, the end of gas processing
After completion, the first gas flow path is changed from the first gas flow path to the first gas flow path.
Gas is supplied at an oblique angle that is radially inclined to the second
To the gas flow path of the second gas flow path.
The by supplying, the replacement gas impact is reduced on the workpiece, it is possible to avoid adverse effects on the object to be processed such as particles.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a gas processing method and apparatus of the present invention are applied to an adhesion processing unit of a system for coating and developing a resist on a semiconductor wafer will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic plan view showing a resist coating / developing processing system incorporating an adhesion processing unit according to the present embodiment.
Is a front view of FIG. 1, and FIG. 3 is a rear view of FIG.

This processing system transfers a wafer W between a cassette station 10, a processing station 20 having a plurality of processing units, and an exposure apparatus (not shown) provided adjacent to the processing station 20. And an interface unit 30.

The cassette station 10 loads a plurality of semiconductor wafers W as objects to be processed, for example, in units of 25 wafers, into a wafer cassette 1 and loads the semiconductor wafers W from another system into this system or from this system to another system. This is for unloading and carrying the wafer W between the wafer cassette 1 and the processing station 20.

In the cassette station 10, as shown in FIG. 1, a plurality of (four in the figure) projections 3 are formed on the cassette mounting table 2 along the X direction in the figure. The wafer cassettes 1 can be placed at a position in a line with the respective wafer entrances facing the processing station 20 side. In the wafer cassette 1, the wafers W are arranged in a vertical direction (Z direction). Also,
The cassette station 10 includes the wafer cassette mounting table 2
And a wafer transfer mechanism 4 located between the processing station 20. The wafer transfer mechanism 4 includes a wafer transfer arm 4a movable in a cassette arrangement direction (X direction) and a wafer arrangement direction (Z direction) of wafers W therein.
The arm 4a allows any one of the wafer cassettes 1 to be selectively accessed. Further, the wafer transfer arm 4a is configured to be rotatable in the θ direction, and an alignment unit (ALI) belonging to a group G3 on the processing station 20 side described later.
M) and the extension unit (EXT).

The processing station 20 is provided with a plurality of processing units for performing a series of steps for performing a coating / phenomenon on the semiconductor wafer W, and these are arranged at predetermined positions in multiple stages. The semiconductor wafer W
Are processed one by one. This processing station 20
As shown in FIG. 1, a main wafer transfer mechanism 21 which is movable in a vertical direction is provided at a central portion.
All processing units are arranged around one wafer transfer space 22. The plurality of processing units are divided into a plurality of processing units, and each processing unit includes a plurality of processing units arranged in multiple stages along a vertical direction. In this embodiment, five processing units G1, G2, G3, G4, and G5 are arranged around the wafer transfer path 22, and the wafer transfer path 22 is a substantially closed space.

Of these, the processing units G1 and G2 are arranged in parallel on the front side of the system (in FIG. 1), the processing unit G3 is arranged adjacent to the cassette station 10, and the processing unit G4 is an interface unit. The processing unit G5 is disposed adjacent to the processing unit 30, and the processing unit G5 is disposed on the back side.

In this case, as shown in FIG.
In this embodiment, two spinner-type processing units for performing a predetermined process by placing the wafer W on a spin chuck (not shown) in the cup 23 are vertically arranged. And a developing unit (DEV) for developing a resist pattern are stacked in two stages from the bottom. Similarly, in the processing section G2, a resist coating unit (COT) and a developing unit (DEV) are stacked in two stages from the bottom as two spinner type processing units. The reason for disposing the resist coating unit (COT) on the lower side in this way is that the waste liquid of the resist liquid is inherently more complicated than the waste liquid of the developer both mechanically and in terms of maintenance. This is because by arranging (COT) in the lower stage, its complexity is reduced. However, if necessary, a resist coating unit (COT) can be arranged in the upper stage.

In the processing section G3, as shown in FIG. 3, an oven-type processing unit for mounting the wafer W on the mounting table 24 (see FIG. 1) and performing a predetermined process, for example, a cooling unit (for cooling the wafer) COL), an adhesion processing unit (AD) which is an object of the present invention, an alignment unit (ALIM) for aligning a wafer,
Extension unit (E
XT), a prebaking unit (PREBAKE) for performing a prebaking process on a wafer, and a postbaking unit (POBAK) for performing a postbaking process on a wafer.
E) are stacked in, for example, eight stages from the bottom. Similarly, the processing unit G4 includes an oven type processing unit such as a cooling unit (COL), an extension cooling unit (EXT · COL), and a cooling unit (C).
OL), a pre-baking unit (PREBADE) and a post-baking unit (POBAKE) are stacked, for example, in eight stages from the bottom.

As described above, the cooling unit (COL) and the extension cooling unit (EXTCOL) each having a low processing temperature are arranged in the lower stage, and the prebaking unit (PREBAKE), the postbaking unit (POBAKE) and the adhesive unit each having a high processing temperature. By arranging the John units (AD) in the upper stage, thermal mutual interference between the units can be reduced. Of course, the arrangement is not limited to this, and other arrangements are also possible.

The processing section G5 located on the back side of the main wafer transfer mechanism 21 basically has a structure in which open processing units are stacked in multiple stages, similarly to the processing sections G3 and G4. The processing section G5 can be moved laterally along the guide rail 67 when viewed from the main wafer transfer mechanism 21. Therefore, since a space is secured by sliding the processing unit G5, maintenance work can be easily performed from behind the main wafer transfer mechanism 21.

The interface section 30 has the same length as the processing station 20 in the X direction. As shown in FIGS. 1 and 2, a portable pickup cassette 3 is provided at the front of the interface section 30.
1 and stationary buffer cassettes 32 are arranged in two stages,
A peripheral exposure device 33 is provided on the back, and a central
A wafer transfer arm 34 is provided. The wafer transfer arm 34 moves in the X and Z directions to move both cassettes 3.
The wafers can be transported to the peripheral exposure devices 33. Further, the wafer transfer arm 34 is rotatable in the θ direction, and the wafer transfer arm 34 is also provided on an extension unit (EXT) belonging to the processing section G4 on the processing station 20 side and a wafer transfer table (not shown) on the adjacent exposure apparatus side. W can be transported.

The processing system configured as described above includes:
Although it is installed in a clean room and thereby increases the cleanliness, the cleanliness of each part is further enhanced by efficiently supplying a vertical laminar flow in the system.

Next, the adhesion processing unit according to the present embodiment will be described. FIG. 4 is a schematic sectional view showing the adhesion processing unit (AD). The adhesion processing unit has a processing chamber 71 in which a semiconductor wafer W as an object to be processed is horizontally supported.

A support mechanism 72 for supporting the semiconductor wafer W
Includes a base 73, a spacer 74 for forming a gap between the base and the object to be processed, and a positioning member 75 for positioning the semiconductor wafer, and a so-called proximity method is employed. As shown in FIG. 5, a plurality of (four in the figure) spacers 74 are provided around the semiconductor wafer W, and a plurality of positioning members 75 are provided corresponding to each spacer. These positioning members 7
5 is screwed to the base 72 with the spacer 74 interposed therebetween. The positioning member 75 holds the semiconductor wafer W by so-called dropping. The base 72 has a heater for heating (not shown).
Is buried.

A plate 76 is detachably provided above the processing chamber 71, and a gas supply unit 77 and a gas discharge unit 78 are provided thereon. A space 80 is formed in the plate 76 by the spacer 79, and this space serves as a flow path of the exhaust gas. A hole 81 that is continuous with the processing chamber 71 is formed outside the bottom of the spacer 76, and exhaust gas from the processing chamber 71 flows into the space 80 through the hole 81.

A gas supply pipe 82 is connected to the gas supply section 77, and HMDS gas and N ₂ gas as processing gases are selectively passed through the gas supply pipe 82 by a valve 83. The gas is supplied to any one of the gas supply units 77. In the gas supply unit 77, a horizontal gas flow path 84 that is continuous with the pipe 82 is formed.
A first gas supply hole 85 extending vertically to the processing chamber 71 near the front end of the processing chamber 4, and extends to the processing chamber 71 in a state of being radially inclined with respect to the first gas supply hole 85 . The second gas supply hole 86 is continuous. This gas supply unit 77
Is provided with a switching mechanism (not shown), so that when the HMDS gas is supplied, the gas supply hole 8 is provided.
5 and the gas supply hole 8 when N ₂ gas is supplied.
6 is switched.

A gas discharge passage 87 is formed in the gas discharge portion 78, and an exhaust pipe 88 is connected to the gas discharge passage 87. An ejector 89 is connected to the exhaust pipe 88. The outlet 87 is provided in the space 8 of the plate 76.
Connected to 0. Therefore, the gas in the processing chamber 71 is exhausted from the exhaust pipe 88 by the exhaust pump 89 through the hole 81, the space 80, and the outlet 87.

The HMDS gas and the N ₂ gas flow through the gas supply pipe 82 as described above.
Is gasified and supplied by an apparatus as shown in FIG. This apparatus has a jar 90 for storing a liquid HMDS 91. An HMDS supply pipe 92 is inserted into the jar 90 to the vicinity of the bottom, and liquid HMDS is supplied from the supply pipe 92. An N ₂ gas supply pipe 93 is inserted into the jar 90 such that the lower end is located above the liquid level in the jar 90. Further, the HMDS gas supply pipe 94 is inserted into the jar 90 such that the lower end is located above the N ₂ gas supply pipe. Reference numeral 95 denotes an overflow pipe for discharging the overflow. The upper part of the jar 90 is closed by a lid 96.

In this state, N ₂ gas is supplied to liquid HMD.
By blowing into S, HMDS as a solvent is volatilized, and the gaseous HMDS is supplied through an HMDS gas supply pipe 94.

Next, the operation of the processing system including the apparatus configured as described above will be described. First, in the cassette station 10, the wafer transfer arm 4 a of the wafer transfer mechanism 4 accesses the cassette 1 containing unprocessed wafers W on the cassette mounting table 2, and one wafer W Take out.

When the wafer W is taken out of the cassette 1, the wafer transfer arm 4a moves the alignment unit (A) disposed in the processing section G3 on the processing station 20 side.
LIM), and the wafer W is placed on the wafer mounting table 24 therein. Then, orientation flat alignment and centering are performed on the wafer W. Thereafter, the wafer transfer body of the main wafer transfer mechanism 21 accesses the alignment unit (ALIM) from the opposite side, and receives the wafer W from the wafer mounting table 24.

In the processing station 20, the main wafer transfer mechanism 21 first loads the wafer W into the adhesion processing unit (AD) according to the present invention belonging to the processing section G3.

Here, first, with the plate 76 set, the inside of the processing chamber 71 is evacuated by the ejector 89. Thereafter, as shown in FIG. 7A, the pipe 82 is set to the HMDS side, and HMDS gas generated by the apparatus of FIG. 6 is introduced. In this case, the HMDS gas is supplied vertically from the gas flow path 84 to the center of the semiconductor wafer W in the processing chamber 71 through the gas supply hole 85. Then, the semiconductor wafer W flows outward from the center of the semiconductor wafer W, further goes upward, and is exhausted from the exhaust pipe 88 through the hole 81, the space 80, and the exhaust port 87.

As described above, the HMDS gas, which is a processing gas, is supplied from the center of the semiconductor wafer W to the outside, and is exhausted upward, so that a very uniform hydrophobic treatment can be performed. Conventionally, such an exhaust is conventionally performed from the lower side, but in this case, the flow of the HMDS gas, which is the processing gas, may be disturbed because the positioning member 75 exists in the exhaust passage. On the other hand, by exhausting the gas to the upper side in this way, the gas can be uniformly processed without generating turbulence in the gas flow.

After the completion of such processing, as shown in FIG. 7B, the ejector 89 is forcibly evacuated so that the atmosphere of the HMDS gas is not released into the atmosphere, and at the same time, the pipe 82 is filled with N. Switch to the ₂ gas side, and introduce N ₂ gas as a replacement gas. In this case, the N2 gas is supplied from the gas flow path 84 through the gas supply holes 86 to the semiconductor wafer W in the processing chamber 71 at an oblique angle slightly inclined from the vertical. Then, the HMDS gas flows toward the outside of the semiconductor wafer W, whereby the HMDS gas is expelled. The expelled HMDS gas and the N2 gas, which is a replacement gas, flow upward from the outside of the processing chamber 71 to the hole 8.
1. Air is exhausted from the exhaust pipe 88 through the space 80 and the exhaust port 87.

In this case, in order to expel the HMDS promptly, it is necessary to flow the N ₂ gas as a replacement gas at a relatively large flow rate. In this case, if the N ₂ gas is supplied through the gas supply holes 85 in the same manner as the HMDS flow path, the N ₂ gas collides perpendicularly with the semiconductor wafer W and may generate particles at this time. On the other hand, when the gas is supplied through a gas supply hole 86 different from the above, the angle becomes slightly oblique from the vertical with respect to the semiconductor wafer W. It is small and can prevent generation of particles.

After the adhesion process is completed, the semiconductor wafer is cooled in the cooling unit (COL), and then the resist is applied by spin coating in the coating unit (COT). Thereafter, pre-baking is performed in the pre-baking unit (PREBAKE), and after being cooled by the cooling unit, peripheral exposure is performed by the peripheral exposure device 33. After that, the semiconductor wafer W is transferred to an adjacent exposure device, and the entire surface is exposed.

When the exposure processing is completed, the wafer transfer arm 34 of the interface unit 30 receives the wafer W, and carries the received wafer W to an extension unit (EXT) belonging to the processing unit group G4 of the processing station 20. Then, the main wafer transfer mechanism 2
1 receives the wafer W, carries it into the developing unit (DEV), and performs a developing process. When the development process is completed, post-baking is performed by a post-baking unit (POBAKE). After that, it is cooled by the cooling unit (COL) and further extended unit (EX)
It is mounted on the mounting table of T). Then, the arm 4a of the cassette station 10 receives the wafer W and puts the wafer W into a predetermined wafer accommodating groove of the cassette 1 for accommodating the processed wafer on the cassette mounting table 2. Thus, a series of processing is completed.

The present invention can be variously modified without being limited to the above embodiment. For example, in the above embodiment, the case of the adhesion process as the gas process has been described, but the present invention is not limited to this. In addition, since the present invention can be applied not only to the adhesion process but also to other gas processes, the object to be processed is not limited to a semiconductor wafer, but may be an LCD substrate, a glass substrate, a CD substrate, a photomask, a printed substrate, etc. Various things are applicable.

[0042]

As described above, according to the present invention,
A gas processing method and apparatus capable of performing good gas processing without causing the attachment of particles and non-uniform processing, etc. are provided.

[Brief description of the drawings]

FIG. 1 is a plan view showing a resist liquid application / development processing system to which an adhesion processing unit as one embodiment of a gas processing apparatus of the present invention is applied.

FIG. 2 is a side view showing the resist liquid application / development processing system of FIG. 1;

FIG. 3 is a rear view showing the resist liquid application / development processing system of FIG. 1;

FIG. 4 is a schematic sectional view showing an adhesion processing unit according to one embodiment of the present invention.

FIG. 5 is a view for explaining a semiconductor wafer support mechanism used in the unit of FIG. 4;

FIG. 6 is a sectional view showing an HMDS gas generator used in the unit shown in FIG. 4;

FIG. 7 is a view for explaining the operation of the unit in FIG. 4;

[Explanation of symbols]

 71 processing chamber 72 semiconductor wafer support mechanism 73 base 74 spacer 75 positioning member 76 plate 77 gas supply section 78 gas discharge section 82 gas supply pipe 84 ... gas flow paths 85, 86 ... gas supply holes 87 ... gas discharge ports 88 ... gas discharge pipes 89 ... ejectors

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-46010 (JP, A) JP-A-7-321329 (JP, A) JP-A-6-283411 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) H01L 21/027

Claims (3)

(57) [Claims] An object to be processed is provided at a central portion of an object to be processed in a processing chamber.
Supply processing gas perpendicular to the bodyThe first gas flow path
Supply process gas viaAnd performing gas treatment, and after the gas treatment,From the first gas flow path, the first gas flow path
Supply gas at an oblique angle that is radially inclined to the gas flow path.
Switching to a second gas flow path to be supplied;  For the object to be processed in the processing chamberThe second gas flow
Through the roadSupplying a replacement gas; supplying the processing gas; and supplying the replacement gas.
Exhausting the inside of the processing chamber when the gas is discharged. 2. A processing chamber, A support mechanism for horizontally supporting the object in the processing chamber, A processing gas and a replacement gas are directed toward an object to be processed in the processing chamber.
A gas supply unit for supplying any one of An exhaust mechanism for exhausting the processing chamber, The gas supply unit is an object to be processed supported by the support mechanism.
First gas that supplies processing gas vertically toward the center of the
A flow path and an obliquely inclined slope with respect to the first gas flow path;
To the workpiece supported by the support mechanism at an angle
The second gas flow path for supplying gas and the gas supplied
Switch between the first gas flow path and the second gas flow path
Gas processing characterized by having a switching mechanism
apparatus. 3. A processing chamber and an object to be processed horizontally in the processing chamber.
A support mechanism for supporting, defining an upper part of the processing chamber, and
A detachable plate, The plate is provided on the plate, and is directed toward an object to be processed in the processing chamber.
To supply either the processing gas or the replacement gas
A supply unit, and a processing gas and a replacement gas supplied to the gas supply unit.
A gas supply pipe for guiding
Be processed Gas or replacement gas
Valve for selectively switching and flowing through the gas supply pipe
And a gas comprising an exhaust mechanism for exhausting the processing chamber.
A gas processing method for performing gas processing by a processing apparatus, The valve is set on the processing gas side, and the valve is
The central part of the object to be processed supported by the support mechanism
Through a first gas flow path for supplying the processing gas vertically toward
Supplying a processing gas to perform gas processing; After the gas processing is completed, the gas flow path is switched to the first by the switching mechanism.
A first gas passage provided from the gas flow path to the first gas supply unit;
The support at an oblique angle inclined radially with respect to the
The second method for supplying the replacement gas to the object to be processed supported by the holding mechanism
Switching to a gas flow path of The valve is set on the replacement gas side, and the
Replacement gas for the object to be processed through the second gas flow path
Supplying a When supplying the processing gas and supplying the replacement gas
Exhausting the processing chamber by the exhaust mechanism
About A gas processing method comprising: