Wafer chuck in semiconductor film deposition equipment

Abstract

The utility model provides a wafer chuck in semiconductor film deposition equipment, which comprises a base, a wafer bearing disc, a vacuum adsorption structure, a heating element, a cooling ring and a support connecting part, the wafer bearing disc is arranged on one surface of the base, and the base is fixed in the semiconductor film deposition equipment through the support connecting part; the cooling ring is arranged in the base and corresponds to the edge of the wafer bearing disc, and the vacuum adsorption structure is arranged in the base in the middle of the cooling ring and corresponds to the center of the wafer bearing disc; the heating elements surround the vacuum adsorption structure, are annularly and uniformly distributed to the edge of the base and bypass the cooling ring; when thin film deposition is carried out, a wafer is fixed on the wafer chuck through the vacuum adsorption structure, the heating element heats the wafer, the cooling ring cools the edge position of the wafer at a preset temperature, and finally the edge position of the wafer can be cooled at the preset temperature in the HARP process. The film thickness of the film deposited on the edge of the wafer on the wafer chuck is close to or consistent with the film thickness of the film deposited in the middle of the wafer.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor thin film deposition, in particular to a wafer chuck in semiconductor thin film deposition equipment. Background Art

[0002] High Aspect Ratio Process (HARP) is a commonly used process in advanced semiconductor manufacturing. The HARP filling process generally uses thin film deposition equipment that can fill high aspect ratio holes or trenches.

[0003] In this thin film deposition equipment, the wafer chuck is an important component. Due to the high aspect ratio process, the process chamber pressure requirement will be higher (600Torr, close to the atmospheric pressure 760Torr), the wafer needs to be fixed on the surface of the wafer chuck so that the wafer is fixed in position throughout the process to ensure the uniformity of the film finally deposited on the wafer surface.

[0004] In the process chamber of this type of thin film equipment, the wafer chuck fixes the wafer by vacuum adsorption. For a schematic diagram of the wafer chuck structure, please refer to Figure 1 A vacuum adsorption gas guide groove 20 is provided at the center of the wafer chuck 10, and the wafer is adsorbed and fixed on the wafer chuck 10 through the vacuum adsorption gas guide groove 20. When thin film deposition is performed, part of the heat at the center of the wafer will be taken away with the adsorbed gas, resulting in the temperature at the center of the wafer being slightly lower than the temperature at the edge. The effect of temperature on the thickness of the film is very significant, so the thickness of the film grown on the wafer will be uneven. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides a wafer chuck in a semiconductor thin film deposition device, comprising a base, a wafer carrying plate, a vacuum adsorption structure, a heating element, a cooling ring and a supporting and connecting component, wherein the wafer carrying plate is arranged on one side of the base, and the base is fixed in the semiconductor thin film deposition device through the supporting and connecting component; the cooling ring is arranged in the base at a position corresponding to the edge of the wafer carrying plate, and the vacuum adsorption structure is arranged at a position of the base in the middle of the cooling ring, corresponding to the position of the center of the wafer carrying plate; the heating element is arranged around the vacuum adsorption structure, evenly distributed in a ring shape to the edge of the base, and bypasses the cooling ring; when thin film deposition is performed, the wafer is fixed on the wafer chuck through the vacuum adsorption structure, the heating element heats the wafer, and the cooling ring cools the edge position of the wafer to a preset temperature.

[0006] Preferably, the cooling ring comprises an annular cooling body, a fluid cooling substance in the annular cooling body, and a cooling substance inlet and outlet communicating with the annular cooling body.

[0007] Preferably, a cooling material flow rate regulating valve is provided at each of the cooling material inlet and outlet.

[0008] Preferably, the cooling substance is cooling water.

[0009] Preferably, a surface of the wafer carrier that contacts the wafer is provided with a plurality of evenly distributed protrusions.

[0010] Preferably, the vacuum adsorption structure includes: two fan-shaped grooves, two suction holes located at the center of the fan-shaped grooves, and two vacuum suction pipes respectively connected to the suction holes; the two suction holes are arranged on the surface of the wafer carrier plate and are symmetrically arranged at positions close to the center of the wafer carrier plate with the same diameter of the wafer carrier plate; the two vacuum suction pipes are arranged in the base.

[0011] Preferably, the heating element comprises a heating wire and an external power line, the heating wire is arranged in a ring shape at the periphery of the vacuum adsorption structure and is arranged in the base avoiding the cooling ring, and the heating wire is powered and heated by the external power line.

[0012] Compared with the prior art, the technical solution of the embodiment of the utility model has the following beneficial effects:

[0013] In the wafer chuck of the semiconductor thin film equipment provided in the utility model, a cooling ring is set at the edge position of the wafer chuck, and the edge position of the wafer is cooled to a preset temperature during the entire process. Ultimately, in the HARP process, the film thickness of the thin film deposited on the edge of the wafer on the wafer chuck is close to or consistent with the film thickness of the thin film deposited in the middle of the wafer, thereby improving the uniformity of the wafer film thickness in the HARP process. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of a wafer chuck in the prior art;

[0015] Figure 2 The internal structure of the wafer chuck provided by an embodiment of the utility model is shown in FIG. Figure 1 (looking down);

[0016] Figure 3 The internal structure of the wafer chuck provided by an embodiment of the utility model is shown in FIG. Figure 2 (Side view).

[0017] Description of reference numerals:

[0018] 10- Wafer chuck;

[0019] 20-vacuum adsorption gas guide groove;

[0020] 30-wafer chuck;

[0021] 301- base;

[0022] 302-vacuum adsorption structure;

[0023] 3021-sector groove;

[0024] 3022-suction hole;

[0025] 3023-Vacuum suction tube;

[0026] 303-cooling ring;

[0027] 3031-annular cooling body;

[0028] 3032-regulating valve;

[0029] 304- heating element;

[0030] 3041-heating wire;

[0031] 3042-External power cord;

[0032] 305-wafer carrier plate;

[0033] 306-Supporting connecting parts

[0034] 307-bump. DETAILED DESCRIPTION

[0035] As described in the background technology, during the HARP process, a portion of the heat at the center of the wafer is taken away by the adsorbed gas, causing the temperature at the center of the wafer to be slightly lower than the temperature at the edge, which in turn causes a technical problem of uneven thickness of the film grown on the wafer.

[0036] In order to solve the above technical problems, the utility model provides a wafer chuck in a semiconductor thin film deposition device, comprising a base, a wafer carrying plate, a vacuum adsorption structure, a heating element, a cooling ring and a supporting and connecting component, wherein the wafer carrying plate is arranged on one side of the base, and the base is fixed in the semiconductor thin film deposition device through the supporting and connecting component; the cooling ring is arranged in the base at a position corresponding to the edge of the wafer carrying plate, and the vacuum adsorption structure is arranged at a position of the base in the middle of the cooling ring, corresponding to the position of the center of the wafer carrying plate; the heating element is arranged around the vacuum adsorption structure, evenly distributed in a ring shape to the edge of the base, and bypasses the cooling ring; when thin film deposition is performed, the wafer is fixed on the wafer chuck through the vacuum adsorption structure, the heating element heats the wafer, and the cooling ring cools the edge position of the wafer to a preset temperature.

[0037] Since the vacuum adsorption structure corresponds to the center of the wafer carrier, when the wafer is adsorbed on the wafer carrier by the vacuum adsorption structure, part of the heat at the center of the wafer will be taken away with the adsorption gas. The utility model cools the edge of the wafer to reduce its temperature to a preset temperature.

[0038] Specifically, the utility model arranges a cooling ring at a position corresponding to the edge of the wafer carrier plate in the base, and cools the edge position of the wafer carrier plate by the cooling ring, and then cools the edge position of the wafer adsorbed on the wafer carrier plate to a preset temperature. Finally, in the HARP process, the film thickness of the thin film deposited on the edge of the wafer on the wafer chuck is close to or consistent with the film thickness of the thin film deposited in the middle of the wafer, thereby improving the uniformity of the wafer film thickness in the HARP process.

[0039] In order to make the above-mentioned purposes, features and beneficial effects of the utility model more obvious and easy to understand, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0040] Please refer to Figure 2 and Figure 3An embodiment of the utility model provides a wafer chuck 30 in a semiconductor thin film deposition device, comprising a base 301, a wafer carrier 305, a vacuum adsorption structure 302, a heating element 304, a cooling ring 303 and a supporting connection component 306. The wafer carrier 305 is used to carry a wafer and is arranged on one side of the base 301. The base 301 is fixed in the semiconductor thin film deposition device through the supporting connection component 306. The cooling ring 303 is arranged in the base 301 at a position corresponding to the edge of the wafer carrier 305. The vacuum adsorption structure 302 is arranged at a position of the base 301 in the middle of the cooling ring 303, corresponding to the central position of the wafer carrier 305. The heating element 304 is arranged around the vacuum adsorption structure 302, and is evenly distributed in a ring shape to the edge of the base 301, and bypasses the cooling ring 303.

[0041] Specifically, the cooling ring 303 is arranged in the base 301 and corresponds to the edge of the wafer carrier 305. When thin film deposition is performed, the wafer is fixed on the wafer chuck 30 by the vacuum adsorption structure 302, the heating element 304 heats the wafer, and the cooling ring 303 cools the edge of the wafer to a preset temperature.

[0042] In one embodiment, the cooling ring 303 includes an annular cooling body 3031, which is arranged in the base 301 and corresponds to the edge position of the wafer carrier 305. The annular cooling body 3031 is provided with a cooling material inlet and a cooling material outlet communicated therewith. When thin film deposition is performed, the cold cooling material flows into the annular cooling body 3031 from the cooling material inlet. In the process of flowing through the annular cooling body 3031, part of the heat at the edge of the wafer will be taken away, thereby cooling the edge of the wafer. The cooling material that takes away part of the heat at the edge of the wafer flows out from the cooling material outlet. This embodiment does not limit the form of the cooling material, which can be a liquid or a gas, etc. At the same time, this embodiment does not limit what kind of substance the cooling material is. In one embodiment, the cooling material is cooling water.

[0043] Furthermore, in order to facilitate the control of the flow rate of the cooling material in the annular cooling body 3031, in one embodiment, a cooling material flow rate regulating valve 3032 is provided at the cooling material inlet and the cooling material outlet.

[0044] The wafer carrier 305 can be integrally formed with the base 301, or can be two independent structural parts. The wafer carrier 305 is fixed to one side of the base 301 by a detachable or non-detachable fixing method, and the utility model does not impose specific restrictions on this. In one embodiment, the wafer carrier 305 is a disc-shaped structure integrally formed on the upper surface of the base 301. The base 301 is fixed in the semiconductor thin film deposition device through the supporting connection component 306.

[0045] Because the wafer is uneven due to stress, it is easy to be misaligned with the wafer carrier 35, resulting in inconsistent heating effects. In one embodiment, the surface of the wafer carrier 305 that contacts the wafer is provided with a number of evenly distributed bumps 307, and the wafer is placed on the bumps 307. The bumps 307 can isolate the wafer from being directly attached to the wafer carrier 305 to avoid uneven heat conduction, which is conducive to uniform heating of the wafer.

[0046] The wafer is adsorbed on the wafer carrier 305 through the vacuum adsorption structure 302. The vacuum adsorption structure 302 is arranged at the position of the base 301 in the middle of the cooling ring 303 and corresponds to the position in the center of the wafer carrier 305. Since the vacuum adsorption structure 302 is a mature technology in this field, the utility model does not limit the specific structure of the vacuum adsorption structure 302. As long as it is a technical solution that can realize the adsorption of the wafer on the wafer carrier 305, it is within the protection scope of the utility model. For example, the vacuum adsorption structure 302 includes at least one air guide groove, and the air guide groove is arranged at the central position of the surface of the wafer carrier 305. A suction hole is also arranged on the air guide groove, and the external vacuum drive device is connected to the suction hole through a vacuum suction pipe. This embodiment does not specifically limit the shape and number of the air guide grooves, which can be set according to actual use requirements. As an embodiment, please refer to Figure 2 and Figure 3 The vacuum adsorption structure 302 includes two fan-shaped grooves 3021, two suction holes 3022 and two vacuum suction pipes 3023. The two fan-shaped grooves 3021 are both arranged on the surface of the wafer carrier 305. The two suction holes 3022 are also arranged on the surface of the wafer carrier 305, and are respectively connected with a corresponding fan-shaped groove 3021. The two suction holes 3022 are respectively connected with a vacuum suction pipe 3023, and the vacuum suction pipe 3023 is arranged in the base 301. When the wafer needs to be adsorbed by the vacuum adsorption structure 302, the vacuum suction pipe 3023 is connected to the vacuum driving device, and the fan-shaped groove 3021 is evacuated by the vacuum driving device, so that the wafer is adsorbed on the wafer carrier 305.

[0047] Furthermore, the two suction holes 3022 are respectively located at the center of the circle where the corresponding fan-shaped groove 3021 is located, and are symmetrically arranged at the same diameter of the wafer supporting plate 305 and close to the center of the wafer supporting plate.

[0048] During thin film deposition, the wafer on the wafer carrier 305 is heated by the heating element 304 . The heating element 304 is disposed around the vacuum adsorption structure 302 , evenly distributed in a ring shape to the edge of the base 301 , and bypasses the cooling ring 303 .

[0049] The heating element 304 is a mature technology in the art, and therefore, the present invention does not limit the specific structure of the heating element 304. In one embodiment, the heating element 304 includes a heating wire 3041 and an external power line 3042. The heating wire 3041 is arranged in a ring shape on the periphery of the vacuum adsorption structure 302 and is arranged in the base 301 away from the cooling ring 303. The heating wire 3041 is powered and heated by the external power line 3042.

[0050] The working principle of wafer chuck is as follows:

[0051] When performing thin film deposition, the wafer is fixed on the wafer carrier 305 by the vacuum adsorption structure 302, and the heating element 304 heats the wafer. Since the vacuum adsorption structure 302 corresponds to the central position of the wafer carrier 305, during the process of adsorbing the wafer on the wafer carrier 305 by the vacuum adsorption structure 302, part of the heat at the central position of the wafer will be taken away with the adsorption gas. In order to ensure that the film thickness of the thin film deposited on the edge of the wafer on the wafer chuck is close to or consistent with the film thickness of the thin film deposited at the middle position of the wafer, the utility model cools the edge position of the wafer to a preset temperature through the cooling ring 303.

[0052] In summary, in the wafer chuck in the semiconductor thin film equipment provided by the utility model, a cooling ring is set at the edge position of the wafer chuck, and the edge position of the wafer is cooled to a preset temperature during the entire process. Ultimately, in the HARP process, the film thickness of the thin film deposited on the edge of the wafer on the wafer chuck is close to or consistent with the film thickness of the thin film deposited in the middle of the wafer, so as to improve the uniformity of the wafer film thickness in the HARP process.

[0053] Although the utility model is disclosed as above, the utility model is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the utility model. Therefore, the protection scope of the utility model shall be subject to the scope defined by the claims.

Claims

1. A wafer chuck in a semiconductor thin film deposition device, characterized in that: It includes a base, a wafer carrier, a vacuum adsorption structure, a heating element, a cooling ring and a supporting and connecting component, wherein the wafer carrier is arranged on one side of the base, and the base is fixed in the semiconductor thin film deposition equipment through the supporting and connecting component; the cooling ring is arranged in the base at a position corresponding to the edge of the wafer carrier, and the vacuum adsorption structure is arranged at a position of the base in the middle of the cooling ring, corresponding to the center of the wafer carrier; the heating element is arranged around the vacuum adsorption structure, evenly distributed in a ring shape to the edge of the base, and bypasses the cooling ring; when thin film deposition is performed, the wafer is fixed on the wafer chuck through the vacuum adsorption structure, the heating element heats the wafer, and the cooling ring cools the edge of the wafer to a preset temperature.

2. The wafer chuck in the semiconductor thin film deposition equipment according to claim 1, characterized in that: The cooling ring includes an annular cooling body, a fluid cooling substance in the annular cooling body, and a cooling substance inlet and an outlet communicating with the annular cooling body.

3. The wafer chuck in the semiconductor thin film deposition equipment according to claim 2, characterized in that: The cooling material inlet and outlet are each provided with a cooling material flow rate regulating valve.

4. The wafer chuck in the semiconductor thin film deposition equipment according to claim 2 or 3, characterized in that: The cooling substance is cooling water.

5. The wafer chuck in the semiconductor thin film deposition equipment according to claim 1, characterized in that: The surface of the wafer carrier plate in contact with the wafer is provided with a plurality of evenly distributed protrusions.

6. The wafer chuck in the semiconductor thin film deposition equipment according to claim 1, characterized in that: The vacuum adsorption structure includes: two fan-shaped grooves, two suction holes located at the center of the fan-shaped grooves, and two vacuum suction pipes respectively connected to the suction holes; the two suction holes are arranged on the surface of the wafer carrier plate and are symmetrically arranged at positions close to the center of the wafer carrier plate with the same diameter of the wafer carrier plate; the two vacuum suction pipes are arranged in the base.

7. The wafer chuck in the semiconductor thin film deposition equipment according to claim 1, characterized in that: The heating element comprises a heating wire and an external power line. The heating wire is arranged in a ring shape at the periphery of the vacuum adsorption structure and is arranged in the base avoiding the cooling ring. The heating wire is powered and heated by the external power line.

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