WO2019240372A1

WO2019240372A1 - Wafer sensor having extended monitoring area and dry process device using same

Info

Publication number: WO2019240372A1
Application number: PCT/KR2019/004934
Authority: WO
Inventors: 강상우; 김용규; 권수용; 문지훈; 김태완
Original assignee: 한국표준과학연구원
Priority date: 2018-06-11
Filing date: 2019-04-24
Publication date: 2019-12-19
Also published as: KR102002625B1

Abstract

A wafer sensor having an extended monitoring area according to the present invention comprises multiple extension pads attached to a support member so as to form a circular shape along the circumference thereof, wherein the extension pads, which are wafer pieces, are attached to the support member to form an extended area arranged between an at least 12-inch basic diameter and an extended diameter. The extended diameter may be configured to reach the outer periphery of an edge ring disposed around an area in which the 12-inch wafer is placed in a process chamber. The wafer sensor can monitor an extension area larger than 12 inches and thus can monitor the temperature and plasma state of the area in which the edge ring is disposed. The wafer sensor can be configured using a 12-inch or smaller wafer which is normally used, and thus can be inexpensively implemented without entailing great expense.

Description

Wafer sensor with extended inspection area, and dry process equipment using the same

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a wafer sensor, and more particularly, to a wafer sensor having an extended inspection area capable of monitoring an area of an edge ring beyond the size of a generally used 12 inch wafer, and a dry type using the same. It relates to a process apparatus.

In the semiconductor manufacturing process, a series of unit processes for forming a film, a pattern, and a wiring are generally performed sequentially, and each unit process is performed through a process facility suitable for the corresponding process conditions.

Referring to FIG. 1, a dry process apparatus 30 using plasma has a chamber 37 in which a vacuum is maintained. An electrostatic chuck 36 is provided below the chamber 37 to support the wafer 10 and serve as a lower electrode for plasma formation.

The heater 35 for controlling the temperature of the wafer 10 is provided inside the electrostatic chuck 36. The upper portion of the chamber 37 is provided so as to face the electrostatic chuck 36 in parallel to supply a reaction gas to the wafer 10, and is provided with a shower head 31 serving as an upper electrode for plasma formation.

The high frequency power, which varies in frequency from the first and second high frequency power sources, is respectively applied to the electrostatic chuck 36 corresponding to the lower electrode and the shower head 31 corresponding to the upper electrode through a matching device (not shown). An RF electric field is formed in the 37. The reaction gas supplied through the shower head 31 is converted into plasma by the RF electric field, and an insulating film or the like formed on the surface of the wafer 10 by the plasmaized reaction gas 33 is formed. Etching is performed on the film to be treated.

The outer circumferential portion of the electrostatic chuck 36 is provided with an edge ring 34 surrounding the wafer 10 supported and fixed thereon at a predetermined interval. The edge ring 34 together with the shield ring 32 installed at the outer circumference of the showerhead 31 serves to focus the plasma 33 formed by the RF electric field onto the wafer 10.

Each process facility is adapted to maintain a constant process condition. In each unit process, process monitoring is carried out before the process is carried out to determine whether the process is progressing, and regular monitoring may be performed.

In addition, process monitoring can be carried out after the replacement of equipment components related to process variables, or after taking necessary measures for equipment outside the process specification.

Process monitoring may be performed by a method of measuring a monitoring parameter of the process after a predetermined process using a wafer sensor. The monitoring parameters are determined according to the characteristics of the unit process. For each unit process, various kinds of wafer sensors may be used according to the monitoring parameters required.

On the other hand, while high yields are currently achieved for the chips present in the center portion of the wafer 10, the chips present in the edge portion of the wafer 10 have relatively high defect rates.

In order to reduce such a defective rate, it is necessary to accurately monitor the temperature and plasma state of the edge portion of the wafer 10 and the peripheral region including the region where the edge ring 34 is disposed. However, since the largest size of a conventionally used wafer is 12 inches, it is difficult to implement a wafer sensor capable of monitoring beyond 12 inches to the area of the edge ring 34.

In addition, a hole is formed inside the edge ring for monitoring the edge ring 34 area, and the temperature inside the edge ring is measured using a laser, but the environment of the space adjacent to the upper edge ring cannot be accurately measured. Hard to trust

In addition, the edge ring 34 may be worn as it continues to be used, thereby changing the temperature or plasma environment around the edge ring, which may affect the processing environment of adjacent wafers.

Accordingly, an object of the present invention is to provide a wafer sensor having an extended inspection area capable of monitoring a process by extending to an area in which an edge ring is disposed.

It is still another object of the present invention to provide a dry process apparatus capable of optimally controlling the temperature in the chamber and the edge ring environment by using a wafer sensor having the extended inspection area.

In order to achieve the above object, an embodiment of the wafer sensor according to the present invention, a 12 inch wafer; And an extension region provided between the diameter (base diameter) and the extension diameter of the 12 inch wafer along the circumference of the 12 inch wafer. In this case, the basic diameter is an extension diameter, and the extension area includes a plurality of individual measurement sensors.

Another embodiment of a wafer sensor according to the present invention comprises: a support member; And a plurality of expansion pads attached to form a circle along the circumference of the support member. Each of the expansion pads is attached to the support member as a piece of wafer to form an extension region provided between at least the base diameter and the extension diameter.

Here, 'base diameter <extension diameter', wherein each expansion pad is provided with at least one individual measurement sensor.

The support member may include an upper support member and a lower support member having the same central axis, and each expansion pad may be configured to be attached between the upper support member and the lower support member.

The upper support member and the lower support member may be configured as a wafer having the basic diameter.

In another embodiment of the wafer sensor according to the present invention, a plurality of expansion pads, which are wafer pieces, are connected to each other so as to form a circular shape and have a ring shape with an empty inside, wherein each of the ring pads has at least a basic diameter. An extension region provided between the extension diameters is formed.

In a ring-shaped embodiment, each of the expansion pads may be connected to each other with the other expansion pads, or may be connected to each other through a supporting member to which each expansion pad is attached.

In addition, the portion to which the expansion pad is attached to the other expansion pad or the other or the support member may be thinner than the other portion.

In each of the above embodiments, the expanded diameter may be configured to extend to at least the outer edge of an edge ring disposed around the place where the wafer of the base diameter is placed in the process chamber.

The expansion pad may be configured by cutting a portion of the wafer on which the individual measurement sensor is formed.

The individual measurement sensor may include one or more of a temperature sensor measuring a temperature, and a plasma sensor measuring a plasma state.

Dry processing apparatus using a wafer sensor according to the present invention, the wafer sensor having the extended inspection area; A heater provided in the electrostatic chuck; A temperature control unit controlling a temperature of the heater; Edge ring; And an edge ring controller for adjusting the height of the edge ring. In this case, the edge ring control unit and the temperature control unit are configured to adjust the height of the edge ring and the temperature of the heater, respectively, in accordance with values measured from each individual measurement sensor of the wafer sensor.

Since the wafer sensor having the extended inspection area according to the present invention can monitor the extended area larger than 12 inches, the temperature and the plasma state of the area where the edge ring is disposed can be monitored.

Since it can be configured using a wafer of 12 inches or less that is commonly used, it can be implemented at low cost without significant cost.

It can monitor not only the edge area of the wafer but also the area where the edge ring is placed, so that the temperature of the wafer or the height of the edge ring can be adjusted according to the state of the area where the edge ring exists, so that the optimal chamber environment can be adjusted. By forming, the defective rate can be lowered.

1 is an example of a dry process apparatus using plasma,

2 is an embodiment of a wafer sensor according to the present invention;

3 is another embodiment of a wafer sensor in accordance with the present invention;

4 is an example of an attachment form between the support member and the expansion pad,

5 is an example using an upper / lower support member,

6 is another embodiment of a wafer sensor in accordance with the present invention;

7 is an embodiment of a dry process apparatus according to the present invention.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description.

However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all transformations, equivalents, and substitutes included in the spirit and scope of the present invention. In the following description of the present invention, if it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

Referring to FIG. 2, the wafer sensor 100 according to the present invention is used to monitor an environment in a chamber, and includes a 12 inch wafer 110 and an expansion area 120.

The extended area 120 refers to an area where the wafer is provided between the diameter (base diameter, d1) and the extended diameter (d2) of the 12 inch wafer. Since the extended area 120 is also a wafer, the area beyond the size of the 12-inch wafer 110 can be monitored.

An extension area 120 is provided between the base diameter d1 and the extension diameter d2, and the extension area 120 is provided with a plurality of individual measurement sensors 130.

12 inches is the diameter of the largest wafer among those currently being manufactured commercially, and the expanded diameter d2 is larger than the base diameter, and may be variously configured.

For example, the extension diameter d2 may be a length that extends to at least the outside of an edge ring disposed around the place where the wafer is placed in the chamber. That is, if the edge ring is disposed adjacent to the edge of the 12 inch wafer and the width of the edge ring is d3, the extension diameter d2 may be at least d1 + d3 + d3.

However, the expanded diameter d2 may be arbitrarily determined depending on how far more monitoring is required beyond the size of the 12 inch wafer.

The expansion region 120 may be formed continuously or intermittently. The number, arrangement, type, etc. of the individual measurement sensors 130 provided in the extended area 120 may be variously configured as necessary. In particular, a temperature sensor measuring a temperature at each point, and a plasma state at the point It may include one or more of the plasma sensor for measuring the.

The method of forming the individual measurement sensor 130 in the wafer sensor 100 may be configured in various ways. For example, the individual measurement sensor 130 may be configured to be sealed to the internal space of the wafer.

Although the individual measurement sensor 130 is basically provided in the extended region 120, the individual measurement sensor 130 may also be provided in the internal wafer region.

That is, while monitoring the temperature and plasma state of the region where the 12-inch wafer sensor 110 is located, the temperature and the plasma state may be measured even for the extended region 120 outside the basic diameter range of 12 inches.

3 shows another embodiment of a wafer sensor with an extended inspection area in accordance with the present invention, comprising a plurality of expansion pads 161-164 attached to form a circle along the circumference of the support member 150. .

Each of the expansion pads 161 to 164 is a piece of wafer, which is circularly attached to the support member 150 along its circumference, thereby forming an extension region 120 provided at least between the base diameter and the extension diameter. The region formed through each of the expansion pads 161 to 164 may be wider than that of the expansion region 120.

The expansion diameter is larger than the base diameter, and the base diameter may be arbitrarily configured.

That is, it can be applied when monitoring for an area larger than the size of a wafer having an arbitrary diameter (base diameter).

3 shows an example in which each of the expansion pads 161 to 164 gather to form a continuous expansion region 120, the expansion region 120 may be formed intermittently.

Although four expansion pads 161 to 164 are used to help understand the description, the size, shape, number, and the like of the expansion pads may be variously configured. In addition, although the support member 150 also shows a circular example, the size, shape, etc. of the support member 150 may be variously configured as necessary.

The expansion pads 161-164 are pieces of wafer used to place the individual measurement sensors 130 in areas outside the basic diameter, and each expansion pad is provided with one or more individual measurement sensors.

The expansion pads 161 to 164 may be configured in various ways. As a specific example, the expansion pads 161 to 164 may be configured by cutting a part of the wafer on which the individual measurement sensor is formed. For example, individual measurement sensors may be formed on commercial wafers such as 6 inches, 8 inches, and 12 inches, and cut into the shape of the necessary expansion pads.

The support member 150 supports each of the expansion pads 161 to 164. That is, each of the expansion pads 161 to 164 is supported by the supporting member.

The support structures of the support members 150 and the expansion pads 161 to 164 may be configured in various ways. Specific examples may be attached to each other using an adhesive. In addition, the support member 150 and the expansion pads 161 to 164 may be separately manufactured and then combined, or may be manufactured integrally as one from the beginning.

The support member 150 may be configured in various ways. For example, a commercial wafer such as 6 inches, 8 inches, 12 inches, or the like can be used as the support member 150, and expansion pads can be attached intermittently or continuously along the circumference of the wafer.

4A is an example showing a horizontal cross section of the wafer sensor shown in FIG. 3.

The wafer sensor may be configured to have a thickness in which the support member 150 and each of the expansion pads 161 to 164 are combined. However, the wafer sensor may be configured to have a thickness thinner than that of other portions as necessary.

For example, if the support member 150 and each of the expansion pads 161 to 164 are configured such that the wafer thickness of the portion to be attached to each other is half the other portion, as shown in FIG. 4B, the support member 150 Even after each of the expansion pads 161 to 164 are attached to each other, the thickness of the entire wafer sensor is equal to the thickness of a single wafer.

Referring to FIG. 5, the support member includes a lower support member 151 and an upper support member 152, and each expansion pad 161 to 164 is disposed between the lower support member 151 and the upper support member 152. It may be configured to be attached to.

In this case, the lower support member 151 and the upper support member 152 may be configured in various ways as long as it can support each expansion pad.

As a specific example, the lower support member 151 and the upper support member 152 may be composed of commercial wafers such as 6 inches, 8 inches, and 12 inches. That is, each expansion pad may be attached between the two wafers along the edge of the wafer.

In such an embodiment, the thickness of the entire wafer sensor may be adjusted by adjusting the thicknesses of the lower support member 151, the upper support member 152, and the expansion pads 161 to 164.

On the other hand, according to another embodiment of the wafer sensor according to the present invention, a plurality of expansion pads, which are wafer pieces, are connected to each other so as to form a circular shape to form a ring shape with an empty inside. Each expansion pad constituting the ring form defines an expansion region provided between at least the base diameter and the extension diameter.

Each expansion pad may be configured by cutting a portion of a wafer on which an individual measurement sensor is formed, and each expansion pad may include an individual measurement sensor such as a temperature sensor for measuring a temperature and a plasma sensor for measuring a plasma state.

In order to form a ring-shaped wafer sensor, wafer pad extension pads must be connected to each other in a ring shape. Each of the expansion pads may be connected to other expansion pads or may be connected to each other through a supporting member.

6 illustrates an example in which the expansion pads 171-1 to 171-4 are connected to each other through the support members 172-1 to 172-4 to form a ring shape.

Each of the supporting members 172-1 to 172-4 is attached to and supported on both side expansion pads at the bottom surface of the portion where the expansion pads 171-1 to 171-4 are connected to each other.

Although not separately illustrated, each of the expansion pads 171-1 to 171-4 may be attached to and connected to ends of adjacent expansion pads without a separate supporting member.

That is, since the expansion pads 171-1 to 171-4 are formed in a ring shape without a support member supporting the common expansion pads, the adjacent expansion pads to the left and right sides should be attached to each other.

In this case, the thickness of each of the expansion pads attached to each other may be thinner than other portions. For example, if the thickness of both ends of each expansion pad, that is, the portions where the expansion pads are attached to each other, is cut in half, the thickness of the wafer in the entire ring-shaped area becomes equal to the thickness of one wafer.

6 shows an example of configuring a ring-shaped wafer sensor with four expansion pads 171-1 to 171-4, but the size, shape, and number of expansion pads constituting the ring-type wafer sensor may be variously configured. Can be.

In addition, the distance between the inner radius and the outer radius of the ring-type wafer sensor may be configured in various ways. That is, the distance between the inner radius and the outer radius of the ring-shaped wafer sensor may be configured to fit the extension area (between the base diameter and the extension diameter), or may be configured wider than that.

The dry process apparatus according to the present invention may be variously configured to process a dry process using plasma, and in particular, the process environment inside the process chamber is controlled by using a wafer sensor.

FIG. 7 illustrates an example of a dry process apparatus 300. An electrostatic chuck 316 supporting a wafer sensor 100 in a lower portion of a chamber 310 in which a vacuum is maintained and serving as a lower electrode for plasma formation. ) Is provided. In addition, the inside of the electrostatic chuck 316 is provided with a heater 315 for adjusting the temperature.

The upper portion of the chamber 310 is provided so as to face in parallel with the electrostatic chuck 316 is provided with a shower head 311 to supply the reaction gas to the wafer sensor 100, and serves as an upper electrode for plasma formation .

The RF field in the chamber 310 is applied to the electrostatic chuck 316 corresponding to the lower electrode and the shower head 311 corresponding to the upper electrode by applying a high frequency power of different frequencies from the first and second high frequency power supplies, respectively, through a matching device. Is formed.

The reaction gas supplied through the shower head 311 is converted into plasma by the RF electric field, and the processing gas such as an insulating film formed on the surface of the wafer is etched by the plasma-formed reaction gas 313.

The outer circumferential portion of the electrostatic chuck 316 is provided with an edge ring 314 surrounding the wafer sensor 100 supported and fixed thereon at a predetermined interval. The edge ring 314 serves to focus the plasma 313 formed by the RF field to the wafer sensor 100 together with the shield ring 312 provided at the outer circumference of the shower head 311.

In particular, the dry process apparatus 300 controls the heater 315 of the electrostatic chuck 316 on which the wafer sensor 100 is placed to control the temperature and adjusts the temperature of the edge ring 314. Edge ring control unit 322 is included.

Here, the individual measurement sensors provided in the wafer sensor 100 may transmit the measured values to the outside in a wired or wireless manner.

The temperature controller 321 adjusts the temperature of the heater 315 according to the value measured from each individual measurement sensor of the wafer sensor 100.

The edge ring controller 322 adjusts the height of the edge ring 314 according to the value measured from each individual measurement sensor of the wafer sensor 100. To this end, the edge ring controller 322 may include an actuator for raising or lowering the edge ring 314 in the vertical direction.

For example, when the temperature distribution changes due to a problem such as wear of the edge ring 314 as the process is repeated, the edge ring 314 may be vertically moved to an appropriate position and the temperature of the heater 315 may be adjusted. have.

While the invention has been shown and described with respect to certain preferred embodiments thereof, it will be understood that the invention may be modified and modified in various ways without departing from the spirit or scope of the invention provided by the following claims. It can be apparent to one of ordinary skill in the art.

[Description of the code]

100: wafer sensor

110: 12 inch wafer

120: extended area

130: individual measuring sensor

150, 151, 152, 172-1 to 172-4: support member

161-164, 171-1-171-4: Expansion pad

300: dry process equipment

311: shower head

313: plasma

314: edge ring

315: heater

316: electrostatic chuck

321: temperature control unit

322: edge ring control unit

Claims

Wafer sensor for monitoring the environment in the process chamber,

12 inch wafer; And

An extension region provided between the diameter (base diameter) and the extension diameter of the 12 inch wafer along the perimeter of the 12 inch wafer ('base diameter <extended diameter'),

The extended area having an extended inspection area with a plurality of individual measurement sensors.
Wafer sensor for monitoring the environment in the process chamber,

Support members; And

A plurality of expansion pads attached to form a circle along a circumference of the support member,

Each of the expansion pads is attached to the support member as a piece of wafer to form an extension region provided between at least the base diameter and the extension diameter (where 'base diameter <extension diameter'),

Each expansion pad having an extended inspection area with at least one individual measurement sensor.
The method of claim 2,

The support member includes an upper support member and a lower support member having the same central axis,

Wherein each expansion pad is attached between the upper support member and the lower support member.
The method of claim 3, wherein

And the upper and lower support members are wafers having the basic diameter.
The method of claim 2,

At least one of the support member and the expansion pad is a wafer sensor having an extended inspection area, characterized in that the thickness of the portion attached to each other is thinner than the other portion.
The method of claim 2,

And said enlarged diameter is configured to extend at least to the outside of an edge ring disposed around said wafer of said base diameter in said process chamber.
The method of claim 2,

And the expansion pad is formed by cutting a portion of the wafer on which the individual measurement sensor is formed.
The method of claim 2,

Wherein said individual measuring sensor comprises at least one of a temperature sensor measuring temperature and a plasma sensor measuring plasma state.
Wafer sensor for monitoring the environment in the process chamber,

A plurality of expansion pads, which are wafer pieces, are connected to each other to form a circle, forming a ring shape with an empty inside,

Each ring-shaped expansion pad forms an extension region provided between at least the base diameter and the extension diameter (where 'base diameter <extension diameter'),

Each expansion pad having an extended inspection area with at least one individual measurement sensor.
The method of claim 9,

Wherein each of the expansion pads is connected to other expansion pads or to each other through a support member to which each of the expansion pads is attached.
The method of claim 10,

And the portion where each of the expansion pads is attached to each other with the other expansion pads or attached to the support member is thinner than the other portions.
The method of claim 9,

And said enlarged diameter is configured to extend at least to the outside of an edge ring disposed around said wafer of said base diameter in said process chamber.
The method of claim 9,

And the expansion pad is formed by cutting a portion of the wafer on which the individual measurement sensor is formed.
The method of claim 9,

Wherein said individual measuring sensor comprises at least one of a temperature sensor measuring temperature and a plasma sensor measuring plasma state.
The method according to claim 2 or 9,

And the base diameter is the diameter of a 12 inch commercial wafer.
In a dry process apparatus for treating a dry process using a plasma,

A wafer sensor having an extended inspection area according to any one of claims 1 to 14;

A heater provided in the electrostatic chuck;

A temperature control unit controlling a temperature of the heater;

Edge ring; And

An edge ring control unit for adjusting the height of the edge ring,

And the edge ring control unit and the temperature control unit respectively adjust the height of the edge ring and the temperature of the heater according to values measured from each individual measurement sensor of the wafer sensor.