JPH0845909A - Sample stand - Google Patents

Abstract

PURPOSE:To freely control the planar temperature distribution of a sample by a method wherein a main body, which is divided into a plurality of temperature control blocks, is provided and the upper surface of the main body is composed of the upper surface of a plurality of temperature control blocks. CONSTITUTION:The sample stand is provided with a main body 10 which is divided into a plurality of temperature control blocks 11, and the upper surface of the main body 10 is composed of the upper surface of a plurality of temperature control blocks 11. For example, the main body 10 is composed of a disc- shaped temperature control block 11a, provided on the center side of the main body 10, and a ring-like temperature control block 11b which is provided outside the block 11a. Besides, the temperature control blocks 11a and 11b have a hollow part respectively, and the introducing pipe 13 and a discharge pipe 14 of a temperature regulating medium, consisting of a cooling medium or heating medium, are connected to each hollow part. A mechanical chuck or an electrostatic chuck and the like is provided on the main body 10, and a wafer sample, to be placed on the main body 10, is closely fixed to the main body 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sample stage installed in a semiconductor manufacturing apparatus such as a dry etching apparatus or a chemical vapor deposition (CVD) apparatus.

[0002]

2. Description of the Related Art Recently, in the field of semiconductor manufacturing, LS
With the high integration of I, the elements formed on the wafer are highly miniaturized. On the other hand, in fine processing such as dry etching and plasma CVD, the temperature of the wafer is an important factor that determines the etching rate and the deposition rate. Therefore, the temperature control of the sample stage on which the wafer is placed is important in advancing the miniaturization of the device.

FIG. 6 shows an example of a conventional sample table. The sample table 5 comprises, for example, a main body 50 and a sample holder 60 provided thereon. The main body 50 has a hollow portion 51, and a temperature adjusting medium composed of a refrigerant or a heating medium circulates in the hollow portion 51. A high frequency power source 52 is connected to the main body 50, and the main body 50 also serves as an electrode for exciting and controlling plasma in the sample table 5.

The sample holding unit 60 is composed of, for example, an electrostatic chuck, and is configured to hold the wafer S as a sample mounted on the upper surface thereof by electrostatic attraction.
In the sample table 5, when the sample S is held by the sample holder 60, the wafer S and the temperature adjusting medium circulating in the hollow portion 51 exchange heat with each other via the sample holder 60. Therefore, the temperature of the wafer S is controlled by adjusting the temperature of the temperature adjusting medium.

[0005]

By the way, in the conventional dry etching apparatus or CVD apparatus, the plasma density generated on the wafer mounted on the sample stage is not uniform in the periphery and the center of the wafer. If the plasma density is not uniform, the etching rate and the deposition rate will be different between the periphery and the center of the wafer. Therefore, it is necessary to control the temperature of the wafer, which is a factor that determines the etching rate and the deposition rate, within the plane of the wafer.

However, in the above-mentioned conventional sample stage, the temperature of the entire surface of the wafer is controlled by the temperature adjusting medium having a required temperature.
It was a system temperature control system. Therefore, it is difficult to adjust the temperature distribution between the periphery and the center of the wafer.
Therefore, in order to make the etching rate and the deposition rate uniform, the flow rate ratio of the mixed gas introduced into the reaction chamber, the pressure in the reaction chamber, the power of the power source, and the like had to be finely adjusted. The present invention has been made to solve the above problems, and an object of the present invention is to provide a sample table that can freely control the in-plane temperature distribution of the sample.

[0007]

In order to solve the above-mentioned problems, the present invention comprises a main body divided into a plurality of temperature control blocks, the upper surface of the main body being constituted by the upper surfaces of the plurality of temperature control blocks. Is.

The present invention is also a sample stage in which the plurality of temperature control blocks are formed in a state where the main body is divided into concentric circles or the main body is radially divided from the center thereof toward the outside. Alternatively, it is a sample table in which the plurality of temperature control blocks are formed while the main body is divided into the concentric circles and the radial divisions.

Further, the present invention is the sample stage in which each of the plurality of temperature control blocks has a hollow portion for circulating the temperature adjusting medium. Further, the present invention is a sample stage in which a heater is provided in each of the plurality of temperature control blocks.

[0010]

In the present invention, since the temperature can be adjusted for each temperature control block, a required temperature distribution is generated on the upper surface of the main body.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a sample table according to the present invention will be described below with reference to the drawings. 1 is a perspective view showing a first embodiment of the present invention, and FIG. 2 is a sectional view of FIG. As shown in the figure, the sample table 1 includes a disk-shaped main body 10 divided into a plurality of temperature control blocks 11. The upper surface of the temperature control block 11 constitutes the upper surface of the main body 1.

The temperature control block 11 is formed so that the main body 10 is divided into concentric circles. For example, in this embodiment, the main body 10 comprises a disc-shaped temperature control block 11a provided on the center side of the main body 10 and a ring-shaped temperature control block 11b provided on the outer side thereof.

Each of the temperature control blocks 11a and 11b has a hollow portion 12. In each hollow portion 12,
An introduction pipe 13 and a discharge pipe 14 for a temperature control medium composed of a refrigerant or a heating medium are connected to each other. Then, in each hollow portion 12, a temperature adjusting medium having a required temperature is circulated through the introduction pipe 13 and the discharge pipe 14. Here, a liquid such as water or ethylene glycol or a gas such as carbon dioxide or nitrogen gas is used as the temperature control medium.

On the main body 10, for example, a mechanical chuck or an electrostatic chuck (neither is shown) is provided. The sample, for example, the wafer S, placed on the main body 10 is closely fixed to the main body 10 by the chuck or the like.

In the sample table 1 thus constructed, the temperature control mediums having different temperatures can be circulated in the temperature control blocks 11a and 11b. Therefore, the temperature around the center and the periphery of the sample table 1 can be adjusted independently,
It becomes possible to generate a desired temperature distribution on the upper surface of the main body 10.

Therefore, according to the sample table 1, the in-plane temperature distribution of the wafer S placed on the sample table 1 can be freely controlled. Therefore, when the sample stage 1 is used in an etching apparatus, the etching rate in the plane of the wafer S can be adjusted, and the in-plane uniformity of etching can be improved. Further, when the sample stage 1 is used in a CVD apparatus, the deposition rate in the surface of the wafer S can be adjusted, so that the in-plane uniformity of film formation can be improved.

Although the main body 10 is divided into two temperature control blocks 11a and 11b in the first embodiment, the main body 10 may be further divided into three or more temperature control blocks 11. In this case, since the in-plane temperature distribution of the wafer S can be controlled more finely,
It is possible to further improve the in-plane uniformity of etching and film formation.

Next, a second embodiment of the present invention will be described with reference to the plane sectional view shown in FIG. As shown in the figure, in this embodiment, the divided state of the temperature control block 21 for dividing the main body 20 is different from that in the first embodiment. That is, the plurality of temperature control blocks 21 are formed in a state in which the disk-shaped main body 20 is radially divided from the center thereof toward the outside. For example, in this embodiment, the main body 20 has three temperature control blocks 21 that are substantially fan-shaped in a plan view and have substantially the same size.
Consists of

Each temperature control block 21 has a hollow portion 22. Further, an inlet pipe and a discharge pipe (not shown) for the temperature control medium are connected to each hollow portion 22 so that the temperature control medium of a required temperature circulates in each hollow portion 22. Has become.

Even in the sample table 2 constructed as described above, the temperature can be adjusted independently for each temperature control block 21, so that a desired temperature distribution can be generated on the upper surface of the main body 20. As a result, the in-plane temperature distribution of the wafer S placed on the sample table 2 can be freely controlled, so that the etching rate and the deposition rate in the plane of the wafer S can be adjusted. Therefore, it is possible to improve the uniformity of etching and film formation within the surface of the wafer S.

In the second embodiment, the case where the main body 20 is divided into three temperature control blocks 21 has been described, but the main body 20 is further divided into four or more temperature control blocks 21.
If divided into, the temperature distribution within the surface of the wafer S can be controlled more finely. Then, the in-plane uniformity of etching and film formation can be further improved.

Next, a third embodiment of the present invention will be described with reference to the plane sectional view shown in FIG. As shown in the figure, in this embodiment, a plurality of temperature control blocks 31 are formed in a state in which a disk-shaped main body 30 is divided into concentric circles and is radially divided outward from the center of the main body 30. There is. For example, in this embodiment, the main body 30 is divided into a combination of the first embodiment and the second embodiment, and is composed of six temperature control blocks 31.

As in the first and second embodiments, each temperature control block 31 has a hollow portion 32. Further, an inlet pipe and a discharge pipe (both not shown) of the temperature control medium are connected to each hollow part 32, so that the temperature control medium of a required temperature circulates in each hollow part 32. Has become.

In the sample table 3 thus constructed, the first
Further, the main body 30 is finely divided by the temperature control block 31 as compared with the second embodiment. Therefore, the temperature of the upper surface of the main body 30 can be controlled more finely, and the desired temperature distribution can be reliably realized. Therefore, since the etching rate and the deposition rate can be adjusted more freely within the surface of the wafer S placed on the sample table 3, the in-plane uniformity of etching and film formation can be further improved.

In the third embodiment, the case where the main body 30 is divided into the six temperature control blocks 31 has been described, but the main body 30 can be divided into smaller pieces. In this case, it goes without saying that the in-plane temperature distribution of the wafer S can be controlled more finely.

Next, a fourth embodiment of the present invention will be described with reference to the plan sectional view shown in FIG. As shown in the figure, also in this embodiment, the main body 40 is composed of a plurality of temperature control blocks 41.
FIG. 4 shows a case where the main body 40 is composed of three temperature control blocks 41 as in the second embodiment, for example. Then, by the upper surfaces of the three temperature control blocks 41, the main body 4
The upper surface of 0 is configured.

On the other hand, a heater 42 is provided in each temperature control block 41. The heater 42 is made of a resistance heating element such as a coil or a nichrome wire. The temperature of each temperature control block 41 can be independently adjusted by each heater 42.

Even in the sample table configured as described above,
Since it is possible to independently adjust the temperature of a predetermined portion of the sample table, it is possible to generate a desired temperature distribution on the upper surface of the main body 40. As a result, the in-plane temperature distribution of the wafer S placed on the sample table can be freely controlled, and the in-plane uniformity of etching and film formation can be improved.

In this embodiment, the case where the heater 42 is provided in the temperature control block 41 in which the main body 40 is radially divided is described. However, the temperature control block is divided into a concentric shape or a combination of concentric and radial shapes. It is also possible to provide a heater in. Even in that case, the fourth
The same effect as the embodiment can be obtained. In addition, the sample stage described in the first to fourth examples is based on the etching device and the CVD.
Needless to say, it is effective as a sample stage of a process apparatus other than the apparatus in which the temperature of the wafer S needs to be adjusted.

[0030]

As described above, in the sample stage of the present invention, it is possible to adjust the temperature of each temperature control block constituting the main body and to generate a required temperature distribution on the upper surface of the main body. Therefore, if this sample table is used, the in-plane temperature distribution of the sample placed on the sample table can be freely controlled, so that the etching rate and the deposition rate in the sample surface can be adjusted. Then, it is possible to improve the in-plane uniformity such as etching and film formation.
Therefore, according to the present invention, a fine element can be formed with high accuracy, which is very effective in promoting high integration of a semiconductor device.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a sectional view showing the first embodiment of the present invention.

FIG. 3 is a plan sectional view showing a second embodiment of the present invention.

FIG. 4 is a plan sectional view showing a third embodiment of the present invention.

FIG. 5 is a plan sectional view showing a fourth embodiment of the present invention.

FIG. 6 is a cross-sectional view showing an example of a conventional sample table.

[Explanation of symbols]

1, 2, 3, 4 Sample stand 10, 20, 30, 40 Main body 11, 11a, 11b, 21, 31, 41 Temperature control block 12, 22, 32 Hollow part 42 Heater S Wafer (sample)

Claims (4)

[Claims] 1. A sample stage comprising a main body divided into a plurality of temperature control blocks, the upper surface of the main body being constituted by the upper surfaces of the plurality of temperature control blocks. 2. The sample stage according to claim 1, wherein the main body is divided into concentric circles, or the main body is radially divided from its center toward the outside, or the main body is divided into the concentric circles. In addition, the sample stage is characterized in that the plurality of temperature control blocks are formed in a state of being radially divided. 3. The sample stage according to claim 1, wherein each of the plurality of temperature control blocks has a hollow portion for circulating a temperature adjusting medium. . 4. The sample stage according to claim 1, wherein a heater is provided in each of the plurality of temperature control blocks.