A wafer fixture for semiconductor thin film deposition

Abstract

The present invention relates to a wafer clamp for semiconductor thin film deposition, which is applied to the technical field related to wafer clamps. Through the mutual coordination of a circle-adjusting clamp bar and a moving circle unit, the wafer can be randomly placed on a backing plate, and then the wafer offset direction can be automatically identified. The moving circle unit can realize automatic adjustment of the position of the wafer, so that it can contact with the eccentric arc parts of two diameter-appropriate clamping plates at the same time, so that the center of the wafer is located on the center line of the circle-adjusting clamp bar, and then the wafer can be driven to a target position and be coaxial with the target position under the action of a negative pressure adsorption head. Compared with the prior art, it can adapt to wafers of different sizes, making the application range wider. On the other hand, it can realize contactless limiting without contacting the deposition surface and edge of the wafer, thereby greatly improving the uniformity and efficiency of wafer thin film deposition.

Description

Technical Field

[0001] The present invention relates to a wafer clamp, and in particular to a wafer clamp for semiconductor thin film deposition applied in the technical field related to wafer clamps. Background Art

[0002] Semiconductor thin film deposition is physical vapor deposition, which includes thermal evaporation deposition and plasma sputtering deposition. Thermal evaporation deposition can be divided into resistance evaporation deposition and electron beam evaporation deposition according to different evaporation methods. Plasma sputtering deposition can also be divided into DC sputtering, RF sputtering and magnetron RF sputtering according to different plasma generation methods.

[0003] When a wafer is undergoing thin film deposition, in order to avoid the influence of airflow on the position of the wafer, it is generally necessary to set up a positioning fixture to limit the position of the wafer, thereby maintaining the stability of thin film deposition. In the prior art, the limiting fixture is generally positioned by clamping, or directly used for positioning on the deposition station through a base with a limiting groove matching the wafer. However, on the one hand, the former needs to contact with the wafer surface during clamping, resulting in a certain degree of obstruction at the clamped position, which affects the stability of thin film deposition. In order to ensure the limiting effect of the latter, the groove diameter is often consistent with the diameter of the target wafer, resulting in it being able to adapt to only one size of wafer, and the scope of application is small. Summary of the invention

[0004] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is that the existing fixture for thin film deposition is prone to affect the uniformity and efficiency of wafer thin film deposition.

[0005] To solve the above problems, the present invention provides a wafer clamp for semiconductor thin film deposition, including a lining plate with a control center, a circle adjusting strip fixedly connected to the upper end of the lining plate, a long hole is drilled in the middle of the lining plate, a moving circle unit is arranged in the long hole, the moving circle unit includes a moving cylinder slidably connected to the inside of the long hole through an electric slide rail, an electric push rod fixedly connected to the inner wall of the long hole away from the middle of the circle adjusting strip, and a negative pressure adsorption head fixedly connected to the extended end of the electric push rod, the moving cylinder is located on the side of the negative pressure adsorption head away from the middle of the circle adjusting strip, and the electric push rod movably penetrates the moving cylinder, a positioning strip is also fixedly inlaid on the upper end of the lining plate, the moving cylinder includes a sliding seat slidably connected to the long hole and a circle shifting unit installed on the upper end of the sliding seat through an electric turntable, the circle shifting unit extends to the top of the lining plate, and the upper end of the sliding seat is lower than the mouth of the long hole.

[0006] In the above-mentioned wafer clamp for semiconductor thin film deposition, by the mutual coordination of the circular adjusting clamp bar and the moving circular unit, limiting can be achieved without contacting the deposition surface and edge of the wafer, and can adapt to wafers of different sizes. After the wafer is placed, the center position of the wafer can be automatically adjusted, so that each wafer can be in the same target position during thin film deposition, ensuring the uniformity and efficiency of wafer thin film deposition.

[0007] As a further improvement of the present application, the rounding clamp strip includes two symmetrical diameter-adjusting clamps, which include a straight section and an arc section fixedly connected to one end of the straight section away from the electric push rod, and the arc sections of the two diameter-adjusting clamps are fixedly connected to each other.

[0008] As a further improvement of the present application, the straight section is a straight structure, the arc section is an arc structure, the centers of the two arc sections are located inside the rounding clamp bar and do not coincide with the center line of the rounding clamp bar, and the arc sections are far away from another diameter-adjusting clamp plate.

[0009] As a further improvement of the present application, the outer edge of the positioning strip fits the inner edge of the rounding clamp strip, a plurality of positioning holes are drilled on the positioning strip, and an infrared rangefinder is installed at the bottom of the positioning holes.

[0010] As a further improvement of the present application, the dial unit includes a base plate, two supporting slide rods connected to the upper end of the base plate, and two push-circle bars respectively rotatably connected to the upper ends of the supporting slide rods. The two push-circle bars are close to each other but not in contact, and the outer ends of the two push-circle bars are wrapped with a silicone layer.

[0011] As another embodiment of the present application, the lower end of the support slide rod is fixedly connected to the bottom plate, and the bottom plate is fixed to the electric turntable.

[0012] As another improvement of the present application, the lower end of the support slide rod is slidably connected to the base plate via an electric slide rail, the vertical section of the support slide rod is arranged off-axis from the push round bar, and the horizontal end of the support slide rod is coaxially distributed with the base plate.

[0013] As another improvement of the present application, a group of adsorption units are further arranged inside the long hole near the middle of the round adjustment clamp strip, and the adsorption units are composed of an electric push rod and a negative pressure adsorption head.

[0014] In summary, through the mutual coordination of the circle-adjusting clamp and the moving circle unit, the wafer can be randomly placed on the backing plate, and then the wafer offset direction can be automatically identified, and the position of the wafer can be automatically adjusted through the moving circle unit so that it can contact the eccentric arc parts of the two diameter-appropriate clamps at the same time, so that the center of the wafer is located on the center line of the circle-adjusting clamp, and then under the action of the negative pressure adsorption head, the wafer can be driven to the target position and be coaxial with the target position. Compared with the existing technology, it can adapt to wafers of different sizes, making it more applicable. On the other hand, it can realize contactless limiting without contacting the deposition surface and edge of the wafer, thereby greatly improving the uniformity and efficiency of wafer thin film deposition. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a three-dimensional diagram of the wafer in the first embodiment of the present application when it is in contact with the rounding clamp bar at the same time;

[0016] Figure 2 This is a three-dimensional diagram of the first embodiment of the present application when the wafer is not clamped;

[0017] Figure 3 This is a schematic diagram of the first embodiment of the present application in which the arc segments of the rounding bar are not concentric with each other;

[0018] Figure 4 This is a three-dimensional diagram of a moving circular unit according to a first embodiment of the present application;

[0019] Figure 5 This is a partial cross-sectional schematic diagram of a positioning strip according to a first embodiment of the present application;

[0020] Figure 6 This is a schematic diagram of the process of adjusting the wafer position by the moving circular unit in the first embodiment of the present application;

[0021] Figure 7 This is a side view of the moving cylindrical part of the second embodiment of the present application;

[0022] Figure 8 This is a schematic diagram of the second embodiment of the present application when the movable cylinder pushes the wafer;

[0023] Fig. 9 This is a front view of the moving cylindrical part of the third embodiment of the present application;

[0024] Fig.10 This is a schematic diagram of the movable cylinder pushing the wafer in the third embodiment of the present application.

[0025] Description of the numbers in the figure:

[0026] 1 lining plate, 101 long hole, 2 circle adjusting clamping strip, 21 straight section, 22 arc section, 3 moving cylinder, 31 sliding seat, 32 circle shifting unit, 321 circle pushing strip, 322 supporting slide bar, 323 bottom plate, 4 electric push rod, 5 negative pressure adsorption head, 6 positioning strip, 61 positioning hole, 62 infrared rangefinder. DETAILED DESCRIPTION

[0027] Three implementation modes of the present application are described in detail below with reference to the accompanying drawings.

[0028] The first implementation method:

[0029] Figure 1-Figure 2 As shown, in the figure, a represents a wafer, a wafer fixture for semiconductor thin film deposition, including a liner 1 with a control center, a circle adjustment clamp 2 is fixedly connected to the upper end of the liner 1, a long hole 101 is drilled in the middle of the liner 1, and a moving circle unit is arranged in the long hole 101, such as Figure 4 The moving circle unit includes a moving cylinder 3 slidably connected to the inside of the long hole 101 through an electric slide rail, an electric push rod 4 fixedly connected to the inner wall of the long hole 101 away from the middle of the circle adjusting clamp strip 2, and a negative pressure adsorption head 5 fixedly connected to the extended end of the electric push rod 4. The moving cylinder 3 is located on the side of the negative pressure adsorption head 5 away from the middle of the circle adjusting clamp strip 2, and the electric push rod 4 movably penetrates the moving cylinder 3. The moving cylinder 3 includes a sliding seat 31 slidably connected to the long hole 101 and a dial unit 32 installed on the upper end of the sliding seat 31 through an electric turntable. The dial unit 32 extends above the lining plate 1, and the upper end of the sliding seat 31 is lower than the mouth of the long hole 101. Figure 6 After the wafer is introduced onto the round-adjusting clamp bar 2, the position of the negative pressure adsorption head 5 is adjusted by the electric push rod 4 so that it is located below the wafer. At this time, the negative pressure adsorption head 5 adsorbs the wafer through the negative pressure, and then the electric push rod 4 continues to extend until the wafer is close to the middle of the round-adjusting clamp bar 2. When the center of the wafer itself coincides with the center of the liner 1, its edge will contact the two arc-shaped parts of the round-adjusting clamp bar 2 at the same time. When the wafer position is offset, it is limited to contacting one of the arc-shaped parts of the round-adjusting clamp bar 2. At this time, it will cover part of the positioning hole 61 on the corresponding side, making the data obtained by the infrared rangefinder 62 smaller. At this time, it can be directly Then, the offset position of the wafer is determined, and then the control center first cuts off the adsorption of the negative pressure adsorption head 5 on the wafer, and controls the movable cylinder 3 to move toward the wafer until they contact each other. After contact, the movable cylinder 3 is continued to be controlled to move in a straight line, and the dial unit 32 is controlled to rotate toward the offset side of the wafer, and the wafer is driven to move toward one side of the center of the circle adjustment clamp 2 through friction force, until the data of multiple infrared rangefinders 62 on both sides of the positioning bar 6 are consistent, indicating that the center of the wafer tends to coincide with the center of the liner 1. At this time, the wafer is continued to be pushed by the movable cylinder 3 so that it contacts the two arc segments 22 of the circle adjustment clamp 2 at the same time.

[0030] like Figure 5A positioning strip 6 is also fixedly embedded on the upper end of the lining plate 1, and the outer edge of the positioning strip 6 fits the inner edge of the diameter adjustment clamp 2. A plurality of positioning holes 61 are drilled on the positioning strip 6, and an infrared rangefinder 62 is installed at the bottom of the positioning hole 61. When the wafer covers the positioning strip 6, the corresponding mouth of the infrared rangefinder 62 is blocked, and its data is the depth of the positioning hole 61, which is relatively small. When it is not covered, the data of the plurality of infrared rangefinders 62 are all greater than the depth of the positioning hole 61 and the data are relatively large. Based on the changes in the data of the plurality of infrared rangefinders 62 corresponding to the positioning strip 6 and the two diameter adjustment clamps, the offset of the wafer can be judged, which is convenient for the control center to automatically control the adjustment of the wafer position.

[0031] like Figure 3 The rounding clamp 2 includes two symmetrical diameter clamps, which include a straight section 21 and an arc section 22 fixedly connected to the end of the straight section 21 away from the electric push rod 4. The arc sections 22 of the two diameter clamps are fixedly connected to each other, the straight section 21 is a straight structure, and the arc section 22 is an arc structure. The centers of the two arc sections 22 are both located on the inner side of the rounding clamp 2 and do not coincide with the center line of the rounding clamp 2, and the arc section 22 is far away from another diameter clamp, so that wafers of different sizes can contact the two arc sections 22 at the same time, and the two contact points are symmetrical, so that the wafers are relatively evenly stressed and not easily damaged. In addition, during subsequent thin film deposition, the rounding clamp 2 is not likely to affect the wafer, effectively ensuring the uniformity of deposition.

[0032] It is worth noting that a group of adsorption units are also arranged inside the long hole 101 near the middle of the rounding clamp 2. The adsorption units are composed of an electric push rod 4 and a negative pressure adsorption head 5. The setting of this group of electric push rods 4 and negative pressure adsorption heads 5 is not necessary and can be selectively set according to actual needs. When the wafer size is large, when the center of the wafer is adjusted to coincide with the center line of the liner 1 or the rounding clamp 2, the two negative pressure adsorption heads 5 simultaneously adsorb and position the wafer, which can improve the stability of the wafer and prevent displacement during thin film deposition. In addition, when two negative pressure adsorption heads 5 are set, the adsorption positions of the two on the wafer do not coincide with its center.

[0033] In the above-mentioned wafer clamp for semiconductor thin film deposition, the wafer can be randomly placed on the backing plate 1 through the mutual coordination of the circle-adjusting clamp bar 2 and the moving circle unit, and then the wafer offset direction can be automatically identified, and the position of the wafer can be automatically adjusted through the moving circle unit so that it can contact the eccentric arc parts of the two diameter-appropriate clamps at the same time, so that the center of the wafer is located on the center line of the circle-adjusting clamp bar 2, and then the wafer can be driven to the target position and coaxial with the target position under the action of the negative pressure adsorption head 5. Compared with the prior art, it can adapt to wafers of different sizes, making the application range wider. On the other hand, it can realize contactless limiting without contacting the deposition surface and edge of the wafer, thereby greatly improving the uniformity and efficiency of wafer thin film deposition.

[0034] The second implementation method:

[0035] This embodiment further improves the dial unit 32 on the basis of the first embodiment, and the rest of the parts remain the same as the first embodiment.

[0036] Figure 7 As shown, the dial unit 32 includes a base plate 323, two supporting slide bars 322 connected to the upper end of the base plate 323, and two pushing strips 321 rotatably connected to the upper ends of the supporting slide bars 322. The two pushing strips 321 are close to each other but not in contact, and the outer ends of the two pushing strips 321 are wrapped with a silicone layer, so that when they come into contact with the wafer, they have a soft contact and are not prone to hard contact. This can not only increase the pushing effect of the pushing strips 321 on the wafer, but also protect the wafer from being damaged. The lower end of the supporting slide bar 322 is fixedly connected to the base plate 323, and the base plate 323 is fixed to the electric turntable.

[0037] like Figure 8 In this embodiment, when the circular push unit 32 needs to rotate to adjust the wafer position, the two circular push bars 321 first revolve with the electric turntable. When the circular push bars 321 come into contact with the wafer, they can rotate due to the friction force, so that the wafer is not easily subjected to excessive force, thereby protecting the wafer from damage. Compared with the first embodiment in which the wafer is pushed only by the rotation of the cylindrical circular push unit 32, the rotation and revolution pushing method of this scheme is more effective and convenient for adjusting the wafer position.

[0038] The third implementation method:

[0039] This embodiment is based on the second embodiment, and the connection method of the support slide bar 322 is changed, and the rest of the parts are consistent with the second embodiment.

[0040] Fig. 9 As shown, the lower end of the support slide bar 322 is slidably connected to the bottom plate 323 through an electric slide rail, the vertical section of the support slide bar 322 is eccentrically arranged with the push round bar 321, and the vertical section is closer to the central axis of the sliding seat 31, so that when the support slide bar 322 slides on the surface of the bottom plate 323 and drives the two push round bars 321 away from each other, the separation between the two push round bars 321 can be larger, and the pushing effect on the wafer is better. The horizontal end of the support slide bar 322 is coaxially distributed with the bottom plate 323. In this embodiment, the push round bar 321 can move radially along the sliding seat 31. In the initial state, the two are in the closest position and are symmetrical about the sliding seat 31. Fig.10When it is necessary to contact the wafer and then push the wafer, one or two of the pushing bars 321 can be controlled to move away from the axis of the sliding seat 31 to increase the distance between the two. When the electric turntable rotates, the revolution range of the two pushing bars 321 is increased, thereby making the distance between the wafer point and the contact point between the wafer and the round adjustment clamp bar 2 smaller, reducing the force angle between the wafer and the round adjustment clamp bar 2, so that when the wafer is pushed, the wafer is easier to move toward the center of the round adjustment clamp bar 2, thereby improving the pushing effect on the wafer and speeding up the adjustment of the wafer position.

[0041] In view of current practical needs, the above-mentioned implementation mode adopted in this application is not limited to the scope of protection. Various changes made within the knowledge scope of technical personnel in this field without departing from the concept of this application still fall within the scope of protection of the present invention.

Claims

1. A wafer fixture for semiconductor thin film deposition, characterized in that: The invention comprises a lining plate (1) with a control center, wherein the upper end of the lining plate (1) is fixedly connected to a circle adjusting clamping strip (2), a long hole (101) is bored in the middle of the lining plate (1), a moving circle unit is arranged in the long hole (101), and the moving circle unit comprises a moving cylinder (3) slidably connected to the inside of the long hole (101) through an electric slide rail, an electric push rod (4) fixedly connected to the inner wall of the long hole (101) away from the middle of the circle adjusting clamping strip (2), and a negative pressure adsorption head (5) fixedly connected to the extended end of the electric push rod (4), wherein the moving cylinder (3) is located on a side of the negative pressure adsorption head (5) away from the middle of the circle adjusting clamping strip (2), and the electric push rod (4) movably penetrates the moving cylinder (3), and the circle adjusting clamping strip (2) comprises two mutually symmetrical diameter-adapting clamping plates, wherein the diameter-adapting clamping plates comprise a straight The straight section (21) and the arc section (22) are fixedly connected to the end of the straight section (21) away from the electric push rod (4), the arc sections (22) of the two diameter-adjusting clamps are fixedly connected to each other, the upper end of the lining plate (1) is also fixedly inlaid with a positioning strip (6), the moving cylinder (3) comprises a sliding seat (31) slidably connected to the long strip hole (101) and a dial unit (32) installed on the upper end of the sliding seat (31) through an electric turntable, the dial unit (32) extends to the top of the lining plate (1), the upper end of the sliding seat (31) is lower than the mouth of the long strip hole (101), the straight section (21) is a straight structure, the arc section (22) is an arc structure, and the centers of the two arc sections (22) are both located inside the circle-adjusting clamp (2) and do not coincide with the center line of the circle-adjusting clamp (2).

2. A wafer fixture for semiconductor thin film deposition according to claim 1, characterized in that: The arc segment (22) is located away from and close to another diameter-appropriate clamping plate.

3. The wafer fixture for semiconductor thin film deposition according to claim 1, characterized in that: The outer edge of the positioning strip (6) fits the inner edge of the rounding clamp strip (2), a plurality of positioning holes (61) are drilled on the positioning strip (6), and an infrared rangefinder (62) is installed at the bottom of the positioning hole (61).

4. The wafer fixture for semiconductor thin film deposition according to claim 1, characterized in that: The rounding unit (32) comprises a bottom plate (323), two supporting slide bars (322) connected to the upper end of the bottom plate (323), and two rounding push bars (321) respectively rotatably connected to the upper ends of the supporting slide bars (322), the two rounding push bars (321) being close to each other but not in contact, and the outer ends of the two rounding push bars (321) are both wrapped with a silicone layer.

5. A wafer fixture for semiconductor thin film deposition according to claim 4, characterized in that: The lower end of the support slide bar (322) is fixedly connected to the bottom plate (323), and the bottom plate (323) is fixed to the electric turntable.

6. A wafer fixture for semiconductor thin film deposition according to claim 4, characterized in that: The lower end of the support slide bar (322) is slidably connected to the bottom plate (323) via an electric slide rail; the vertical section of the support slide bar (322) is arranged off-axis from the push round bar (321); and the horizontal end of the support slide bar (322) is coaxially distributed with the bottom plate (323).

7. The wafer fixture for semiconductor thin film deposition according to claim 1, characterized in that: A group of adsorption units is also provided inside the long strip hole (101) near the middle of the round adjustment clamp strip (2), and the adsorption units are composed of an electric push rod (4) and a negative pressure adsorption head (5).

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