Reaction chamber structure

Abstract

The utility model provides a reaction cavity structure. The reaction cavity structure comprises a cavity body, a sucking disc and a baffle plate, the baffle plate surrounds the side wall of the suction cup and is nested in the cavity, the outer contour of the baffle plate is matched with the contour of the side wall of the cavity, a gap is formed between the baffle plate and the side wall of the cavity, and the top surface of the baffle plate is lower than the top surface of the suction cup in the direction perpendicular to the top surface of the suction cup. Through the baffle plate, a thin film formed in a deposition process is deposited on the surface of the baffle plate, so that the bottom wall of the cavity is protected, the influence of an etching process on the bottom wall of the cavity is reduced, metal particles generated by etching the bottom wall of the cavity are reduced, the concentration of the metal particles in the reaction cavity is reduced, and the yield of the reaction cavity is improved. And therefore, the problem of white pixels on the surface of the wafer caused by the metal particles can be reduced, and the yield of the wafer can be improved.

Description

Technical Field

[0001] The utility model relates to the semiconductor field, in particular to a reaction chamber structure. Background Art

[0002] With the continuous development in recent years, most chip factories generally use plasma enhanced chemical vapor deposition (PECVD) or high-density plasma chemical vapor deposition (HDPCVD) to fill the insulating medium. This process has a good filling effect for intervals less than 0.8 microns.

[0003] The HDPCVD process is often used in the trench filling process of the shallow trench isolation (STI) process. The HDPCVD process is completed inside the same reaction chamber through deposition-etching-deposition steps. In the etching step, not only the silicon wafer is etched, but also the entire reaction chamber is etched. Therefore, a large number of metal particles will be generated inside the reaction chamber during the etching step. When the metal particles enter the surface of the wafer, the metal content on the surface of the wafer will be increased, thereby seriously affecting the number of white pixels (White Pixel) of the wafer. In addition, a large number of particles (PA) will be generated in the etching step, and the particles falling at the bottom of the reaction chamber will affect the cleanliness of the reaction chamber environment. If the environment of the reaction chamber is poor, it will seriously affect the performance of the thin film deposited on the surface of the wafer in the deposition step. Therefore, it is particularly important to keep the entire reaction chamber clean.

[0004] How to provide a reaction chamber that can reduce the impact of etching on the white pixels of the wafer and the impact of particles generated by etching on the quality of the thin film generated on the wafer surface during the deposition and etching processes is an issue that the industry urgently needs to solve. Summary of the invention

[0005] The technical problem to be solved by the utility model is to provide a reaction chamber structure, which can reduce the metal particles in the reaction chamber during the deposition and etching processes, thereby reducing the adverse effects of the particles on the wafer surface.

[0006] In order to solve the above problems, the utility model provides a reaction chamber structure, comprising: a cavity; a suction cup, arranged in the cavity, the top surface of the suction cup is used to adsorb and fix the wafer; a shielding plate, surrounding the side wall of the suction cup and nested in the cavity, and the outer contour of the shielding plate is adapted to the contour of the side wall of the cavity, and has a gap with the side wall of the cavity, and in the direction perpendicular to the top surface of the suction cup, the top surface of the shielding plate is lower than the top surface of the suction cup.

[0007] In some embodiments, in a direction perpendicular to the top surface of the suction cup, the bottom surface of the shielding plate is higher than the bottom surface of the suction cup.

[0008] In some embodiments, the plane where the top surface of the shielding plate is located is parallel to the plane where the top surface of the suction cup is located.

[0009] In some embodiments, in a direction perpendicular to the top surface of the suction cup, the bottom surface of the shielding plate is connected to the bottom wall of the cavity.

[0010] In some embodiments, the cavity is cylindrical in shape.

[0011] In some embodiments, the shielding plate is ring-shaped.

[0012] In some embodiments, the shielding plate is in a spiral shape.

[0013] In some embodiments, the shielding plate is movable with the suction cup.

[0014] In some embodiments, the shielding plate is made of ceramic.

[0015] In some embodiments, the shielding plate is a detachable component.

[0016] The above technical solution adds a shielding plate to the cavity of the reaction chamber, the shielding plate surrounds the side wall of the suction cup, the shielding plate surrounds the side wall of the suction cup and is nested in the cavity, and the outer contour of the shielding plate is matched with the contour of the side wall of the cavity, and has a gap with the side wall of the cavity, and in the direction perpendicular to the top surface of the suction cup, the top surface of the shielding plate is lower than the top surface of the suction cup. The shielding plate allows the thin film formed during the deposition process to be deposited on the surface of the shielding plate, thereby protecting the bottom wall of the cavity, reducing the impact of the etching process on the bottom wall of the cavity, reducing the metal particles generated by etching the bottom wall of the cavity, reducing the concentration of metal particles in the reaction chamber, and then reducing the white pixel problem on the wafer surface caused by metal particles, thereby improving the wafer yield.

[0017] It should be understood that the above general description and the detailed description below are only exemplary and explanatory and cannot limit the present invention. The techniques, methods and devices known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the techniques, methods and devices should be considered as part of the authorization specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments of the utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a top view schematic diagram of the reaction chamber structure provided by the first embodiment of the utility model;

[0020] Figure 2 It is a schematic diagram of the front view of the interior of the reaction chamber structure provided by the first embodiment of the utility model;

[0021] Figure 3 is a schematic top view of a shielding plate provided in the first embodiment of the utility model;

[0022] Figure 4 It is a top view schematic diagram of the reaction chamber structure provided by the second embodiment of the utility model;

[0023] Figure 5A It is a schematic diagram of the front view of the interior of the reaction chamber structure provided by the second embodiment of the utility model;

[0024] Figure 5B It is a rear view schematic diagram of the interior of the reaction chamber structure provided by the second embodiment of the utility model;

[0025] Figure 6 It is a schematic top view of a shielding plate provided in the second embodiment of the utility model. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] Please also read Figure 1 to Figure 3 ,in, Figure 1 is a top view schematic diagram of the reaction chamber structure provided by the first embodiment of the utility model, Figure 2 This is a schematic diagram of the interior of the reaction chamber structure provided by the first embodiment of the utility model. Figure 3 It is a schematic top view of the shielding plate provided in the first embodiment of the utility model.

[0028] like Figure 1 , Figure 2 As shown, in this embodiment, the reaction chamber structure includes: a chamber, a suction cup 11, and a shielding plate 12. The suction cup 11 is arranged in the chamber, and the top surface 110 of the suction cup 11 is used to adsorb and fix the wafer. The shielding plate 12 surrounds the side wall of the suction cup 11 and is nested in the chamber, and the outer contour of the shielding plate 12 is adapted to the contour of the side wall 101 of the chamber, and has a gap 102 with the side wall 101 of the chamber; in the direction perpendicular to the top surface 110 of the suction cup 11 (the direction D1 shown in the figure), the top surface 120 of the shielding plate 12 is lower than the top surface 110 of the suction cup 11.

[0029] In this embodiment, the reaction chamber structure is used for a high-density plasma chemical vapor deposition process, including a deposition-etching-deposition process step, the shell of the chamber is metal, and the suction cup 11 is an electrostatic suction cup. The top surface 120 of the shielding plate 12 is lower than the top surface 110 of the suction cup 11, so that the shielding plate 12 can avoid affecting the wafer adsorbed by the suction cup 11.

[0030] The shielding plate 12 surrounds the side wall of the suction cup 11 and is nested in the cavity, and the outer contour of the shielding plate 12 is adapted to the contour of the side wall 101 of the cavity, that is, the shape formed by the vertical projection of the shielding plate 12 and the suction cup 11 on the bottom wall of the cavity is basically the same as the shape of the bottom wall of the cavity, so that the thin film formed during the wafer thin film deposition process is simultaneously deposited on the top surface 120 of the shielding plate 12, so that the bottom wall of the cavity is protected, reducing the metal particles generated on the bottom wall of the cavity during the etching process, thereby reducing the metal particles on the surface of the wafer, and further reducing the problem of white pixels on the surface of the wafer caused by too many metal particles. In this embodiment, the shape of the cavity is cylindrical, and the bottom wall of the cavity is circular. Accordingly, the shape formed by the vertical projection of the shielding plate 12 and the suction cup 11 on the bottom wall of the cavity is circular, which can better cover the bottom wall of the cavity.

[0031] like Figure 2 As shown, in this embodiment, in a direction perpendicular to the top surface 110 of the suction cup 11 (in the direction D1 in the figure), the bottom surface 129 of the shielding plate 12 is higher than the bottom surface 119 of the suction cup 11. That is, the shielding plate 12 can be a thin plate that only surrounds the side wall of the suction cup 11.

[0032] In this embodiment, the shielding plate 12 is in the shape of a ring. Figure 3 As shown, the shielding plate 12 is in the shape of a ring and has two openings 121. Figure 2 As shown, a fastening device 122 is further provided below the split opening 121 .

[0033] like Figure 2 As shown, the plane where the top surface 120 of the shielding plate 12 is located is parallel to the plane where the top surface 110 of the suction cup 11 is located.

[0034] In some embodiments, the bottom surface 129 of the baffle plate 12 is connected to the bottom wall of the cavity, that is, the baffle plate 12 not only surrounds the side wall of the suction cup 11, but also reaches the bottom wall of the cavity, so that the bottom wall of the cavity can be better protected. Specifically, the bottom surface of the baffle plate 12 is connected to the bottom wall of the cavity, so that during the deposition process, the bottom wall of the cavity is better shielded, and the bottom wall of the cavity is further protected from being etched during the etching process, thereby reducing the metal particles generated by the bottom wall of the cavity during the etching process, improving the cleanliness of the bottom wall of the cavity, reducing the concentration of metal particles in the cavity, and further reducing the impact of the metal particles on the wafer surface. In addition, the bottom surface 129 of the baffle plate 12 connected to the bottom wall of the cavity can also fix the baffle plate 12 more stably.

[0035] In this embodiment, the shielding plate 12 can move with the suction cup 11. After the shielding plate 12 is fixed around the side wall of the suction cup 11, the shielding plate 12 can move with the suction cup 11, and the gap 102 between the shielding plate 12 and the side wall 101 of the cavity can facilitate the shielding plate 12 to move with the suction cup 11 in the cavity, and the gap 102 can prevent the shielding plate 12 from affecting the side wall 101 of the cavity during its movement.

[0036] In this embodiment, the shielding plate 12 is a detachable component, and the split 121 can be used for disassembly and assembly. When the split 121 is split, the inner diameter of the shielding plate 12 increases, and the shielding plate 12 can be more conveniently sleeved on the side wall of the suction cup 11; when the split 121 is locked by the fastening device 122, the shielding plate 12 can be fastened to the side wall of the suction cup 11, thereby fixing the shielding plate 12 to the side wall of the suction cup 11. When the shielding plate 12 reaches the end of its service life, the old shielding plate can be quickly removed and a new shielding plate can be installed.

[0037] In this embodiment, the shielding plate 12 is made of ceramics. Ceramic materials are stable in properties, resistant to high temperatures and oxidation, and have high hardness, and are suitable for use in high-density plasma chemical vapor deposition processes.

[0038] Please also read Figures 4 to 6 ,in, Figure 4 It is a top view schematic diagram of the reaction chamber structure provided by the second embodiment of the utility model; Figure 5A It is a schematic diagram of the front view of the interior of the reaction chamber structure provided by the second embodiment of the utility model; Figure 5B It is a rear view schematic diagram of the interior of the reaction chamber structure provided by the second embodiment of the utility model; Figure 6 It is a schematic top view of a shielding plate provided in the second embodiment of the utility model.

[0039] like Figure 4 , Figure 5A ,as well as Figure 5B As shown, in this embodiment, the reaction chamber structure includes: a chamber, a suction cup 11, and a shielding plate 22. The suction cup 11 is arranged in the chamber, and the top surface of the suction cup is used to absorb and fix the wafer; the shielding plate 22 surrounds the side wall of the suction cup 11 and is nested in the chamber, and the outer contour of the shielding plate 22 is adapted to the contour of the side wall of the chamber, and has a gap 102 with the side wall of the chamber, and in the direction perpendicular to the top surface 110 of the suction cup 11 (in the figure D1 direction), the top surface of the shielding plate 22 is lower than the top surface 110 of the suction cup 11.

[0040] In this embodiment, the reaction chamber structure is used for a high-density plasma chemical vapor deposition process, including deposition-etching-deposition process steps, the shell of the chamber is metal, and the suction cup 11 is an electrostatic suction cup. The top surface of the shielding plate 22 is lower than the top surface of the suction cup 11, that is, the highest point of the shielding plate 22 along the D1 direction is lower than the top surface 110 of the suction cup 11, so as to prevent the shielding plate 22 from affecting the wafer adsorbed by the suction cup 11.

[0041] The shielding plate 22 surrounds the side wall of the suction cup 11 and is nested in the cavity, and the outer contour of the shielding plate 22 is adapted to the contour of the side wall 101 of the cavity, that is, the vertical projection of the shielding plate 22 and the suction cup 11 on the bottom wall of the cavity is basically the same as the bottom wall of the cavity, so that the thin film formed during the wafer thin film deposition process is simultaneously deposited on the surface of the shielding plate 22, so that the bottom wall of the cavity is better protected, and the metal particles generated on the bottom wall of the cavity during the etching process are reduced, thereby reducing the metal particles on the surface of the wafer, and further reducing the problem of white pixels on the surface of the wafer caused by too many metal particles. In this embodiment, the shape of the cavity is cylindrical, and the bottom wall of the cavity is circular. Accordingly, the vertical projection of the shielding plate 22 and the suction cup 11 on the bottom wall of the cavity is circular, which can better cover the bottom wall of the cavity.

[0042] In this embodiment, the shielding plate 22 is in a spiral shape. Figure 5A , Figure 5B As shown, the shielding plate 22 is a spiral sheet separated at the head and tail ends, and has different heights. Figure 6 As shown, the vertical projection of the shielding plate 22 on the bottom wall of the cavity is in the shape of a circular ring, and Figure 6 Also shown is the intersection 221 of the first spiral layer and the second spiral layer on the vertical projection of the bottom wall of the cavity, and the vertical projection of the shielding plate 22 and the suction cup 11 on the bottom wall of the cavity together form a circular shape.

[0043] like Figure 5A , Figure 5B As shown, in this embodiment, in the direction perpendicular to the top surface 110 of the suction cup 11 (in the direction D1 in the figure), the bottom surface of the shielding plate 22 is higher than the bottom surface 119 of the suction cup 11. That is, the shielding plate 22 only surrounds the side wall of the suction cup 11, and the head end 222 and each spiral surface of the spiral shielding plate 22 are higher than the bottom surface 119 of the suction cup 11.

[0044] In this embodiment, the shielding plate 22 is detachable. The head end 222 and the tail end 223 of the spiral shielding plate 22 are separated and have a height difference, so that the shielding plate 22 can be sleeved on the side wall of the suction cup 11, and the tail end 223 of the shielding plate 22 is connected to the base of the suction cup 11, so that the shielding plate 22 can be better fixed. When the shielding plate 22 reaches the end of its service life, it can be quickly replaced with a new shielding plate.

[0045] When the baffle plate 22 is fixed to the side wall of the suction cup 11, the baffle plate 22 can move with the suction cup 11, and the gap 102 between the baffle plate 22 and the side wall 101 of the cavity can facilitate the baffle plate 22 to move with the suction cup 11 in the cavity, and the gap 102 can prevent the baffle plate 22 from affecting the side wall 101 of the cavity.

[0046] In this embodiment, the material of the shielding plate 12 is ceramic.

[0047] In another embodiment, the spiral shielding plate 22 is composed of multiple turns of spirals, and the shielding plate 22 surrounds the side wall of the suction cup 11 and is nested in the cavity, and the outer contour of the shielding plate 22 is adapted to the contour of the side wall 101 of the cavity. Specifically, the vertical projection of the shielding plate 22 and the suction cup 11 on the bottom wall of the cavity is substantially the same as the bottom wall of the cavity, and can better cover the bottom wall of the cavity. When the bottom wall of the cavity is circular, the vertical projection of the shielding plate 22 and the suction cup 11 on the bottom wall of the cavity is circular, and can basically cover the bottom wall of the cavity. The multi-turn spiral baffle plate 22 allows the bottom wall of the cavity to be better shielded during the deposition process, thereby improving the cleanliness of the bottom wall of the cavity and further protecting the bottom wall of the cavity from being etched during the etching process, thereby reducing the metal particles generated on the bottom wall of the cavity during the etching process, reducing the concentration of metal particles in the cavity, and further reducing the impact of the metal particles on the wafer surface.

[0048] In some embodiments, the inner radius of different spiral turns of the multi-turn spiral shielding plate 22 is different to facilitate disassembly. However, the shielding plate 22 still surrounds the side wall of the suction cup 11 and is nested in the cavity, and the outer contour of the shielding plate 22 is adapted to the contour of the side wall 101 of the cavity, that is, the shape formed by the vertical projection of the shielding plate 22 and the suction cup 11 on the bottom wall of the cavity is basically the same as the bottom wall of the cavity, which can better cover the bottom wall of the cavity. When the bottom wall of the cavity is circular, the shape formed by the vertical projection of the shielding plate 22 and the suction cup 11 on the bottom wall of the cavity is circular, which can basically cover the bottom wall of the cavity.

[0049] In some embodiments, the spiral tail end 223 of the shielding plate 12 directly reaches the bottom wall of the cavity, so that the shielding plate 22 can be more stably fixed inside the cavity.

[0050] The above technical solution provides a reaction chamber structure, which includes a cavity, a suction cup and a shielding plate. The shielding plate surrounds the side wall of the suction cup and is nested in the cavity, and the outer contour of the shielding plate is adapted to the contour of the side wall of the cavity, and has a gap with the side wall of the cavity. In the direction perpendicular to the top surface of the suction cup, the top surface of the shielding plate is lower than the top surface of the suction cup. The shielding plate allows the thin film formed during the deposition process to be deposited on the surface of the shielding plate, thereby protecting the bottom wall of the cavity, reducing the impact of the etching process on the bottom wall of the cavity, reducing the metal particles generated by etching the bottom wall of the cavity, reducing the concentration of metal particles in the reaction chamber, and further reducing the white pixel problem on the wafer surface caused by metal particles, thereby improving the wafer yield.

[0051] It should be noted that, in this document, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion. The various embodiments in this specification are described in a related manner, and the same and similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0052] The above is only a preferred embodiment of the utility model, and is not intended to limit the protection scope of the utility model. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principle of the utility model, and these improvements and modifications should also be regarded as the protection scope of the utility model.

Claims

1. A reaction chamber structure, characterized in that: include: Cavity; A suction cup is disposed in the cavity, and the top surface of the suction cup is used to absorb and fix the wafer; A shielding plate surrounds the side wall of the suction cup and is nested in the cavity, and the outer contour of the shielding plate is adapted to the contour of the side wall of the cavity and has a gap with the side wall of the cavity. In the direction perpendicular to the top surface of the suction cup, the top surface of the shielding plate is lower than the top surface of the suction cup.

2. The reaction chamber structure according to claim 1, characterized in that: In a direction perpendicular to the top surface of the suction cup, the bottom surface of the shielding plate is higher than the bottom surface of the suction cup.

3. The reaction chamber structure according to claim 1, characterized in that: The plane where the top surface of the shielding plate is located is parallel to the plane where the top surface of the suction cup is located.

4. The reaction chamber structure according to claim 1, characterized in that: The bottom surface of the shielding plate is connected to the bottom wall of the cavity.

5. The reaction chamber structure according to claim 1, characterized in that: The cavity is cylindrical in shape.

6. The reaction chamber structure according to claim 1, characterized in that: The shielding plate is in a ring shape.

7. The reaction chamber structure according to claim 1, characterized in that: The shielding plate is in a spiral shape.

8. The reaction chamber structure according to claim 1, characterized in that: The shielding plate can move along with the suction cup.

9. The reaction chamber structure according to claim 1, characterized in that: The material of the shielding plate is ceramic.

10. The reaction chamber structure according to claim 1, characterized in that: The shielding plate is a detachable component.

Images