A device for improving film formation on the side of a wafer

Abstract

The present application provides a device for improving film formation on the side of a wafer, and relates to the field of semiconductor equipment technology, including a process chamber, a heating plate is arranged in the process chamber, the heating plate is used to place a wafer, and a spray upper plate is also arranged above the heating plate, and a process gas is introduced toward the top of the wafer through the spray upper plate to form a film on the surface of the wafer, and a barrier structure is arranged on the side of the heating plate to prevent the process gas from contacting the side of the wafer to avoid film formation on the side of the wafer. The function of the barrier structure is to prevent the process gas from contacting the side of the wafer, so that the situation of film formation on the side of the wafer due to the process gas contacting the side of the wafer can be avoided, and the probability of film formation on the side of the wafer is reduced, and the cleanliness of the wafer itself caused by film formation on the side of the wafer in the prior art is improved, as well as the cleanliness of the process chamber and subsequent transmission channels caused by long-term process accumulation, thereby improving the stability of the overall wafer process and ensuring the process quality of the wafer.

Description

Technical Field

[0001] The present application relates to the field of semiconductor equipment technology, and in particular to a device for improving film formation on the side of a wafer. Background Art

[0002] During the semiconductor manufacturing process, chemical vapor deposition is often performed on the surface of the wafer on a heating plate using specific process gases to form a thin film on the surface of the wafer.

[0003] Generally, there are thickness requirements for the thin film on the surface of the wafer. When the film is formed within a certain thickness range, it is easy for film liquid to accumulate on the side of the wafer, causing film to be formed on the side of the wafer as well. However, when the film is formed on the wafer, it is required that the film is formed only on the surface of the wafer, and no film layer is formed on the side of the wafer. This does not meet the film formation requirements of the wafer. Moreover, when the film is formed on the side of the wafer, a complete film layer is not formed like the surface of the wafer, but intermittent film flocs of varying thickness are formed on the side of the wafer, which affects the cleanliness of the wafer. On the other hand, when the side of the wafer has film flocs, the wafer will also bring the side film flocs to the subsequent process equipment, causing interference to the subsequent process, and affecting the cleanliness of the film forming chamber and the subsequent transmission channel, which is not conducive to the process stability of the wafer. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a device for improving film formation on the side of a wafer, which can improve the film formation on the side of the wafer and enhance the process stability of the wafer.

[0005] According to one aspect of an embodiment of the present application, there is provided a device for improving film formation on the side of a wafer, comprising: a process chamber, wherein a heating plate is disposed in the process chamber, the heating plate is used to place the wafer, a spray upper plate is also disposed above the heating plate, a process gas is introduced toward the top of the wafer through the spray upper plate to form a film on the surface of the wafer, and a barrier structure is disposed on the side of the heating plate to prevent the process gas from contacting the side of the wafer to avoid film formation on the side of the wafer.

[0006] Optionally, a receiving groove is formed on the surface of the heating plate, the wafer is arranged in the receiving groove, an inclination angle is provided between the groove wall of the receiving groove and a horizontal plane, a gap is formed between the side of the wafer and the groove wall of the receiving groove, and the blocking structure includes a blocking foot extending into the gap, and a blocking part connected to the blocking foot and arranged on the side of the heating plate.

[0007] Optionally, the blocking foot has a first surface close to the groove wall and a second surface close to the wafer, the first surface forms a first angle matching the inclination angle with the horizontal plane, and the second surface forms a second angle with the horizontal plane.

[0008] Optionally, the first angle is between 30° and 40°.

[0009] Optionally, the second angle is between 30° and 90°.

[0010] Optionally, the thickness of the barrier portion is between 0.5 mm and 2 mm.

[0011] Optionally, the blocking portion includes a first blocking portion and a second blocking portion arranged in parallel, and a connecting portion connecting the first blocking portion and the second blocking portion to form a semi-enclosed structure wrapped around the side of the heating plate, the first blocking portion is located on the side of the heating plate accommodating the wafer, and the blocking foot is connected to the side of the first blocking portion close to the wafer.

[0012] Optionally, a slot is further provided on the inner wall of the connecting portion close to the heating plate.

[0013] Optionally, the material of the barrier structure includes at least ceramic or sapphire.

[0014] The device for improving film formation on the side of a wafer provided in an embodiment of the present application comprises a heating plate in a process chamber and an upper spray plate above the heating plate. When the upper spray plate sprays process gas toward the wafer on the heating plate, a film layer can be formed on the surface of the wafer. In order to avoid the formation of a film layer on the side of the wafer, a barrier structure is provided on the side of the heating plate. The function of the barrier structure is to prevent the process gas from contacting the side of the wafer. In this way, the situation in which film formation on the side of the wafer due to the process gas contacting the side of the wafer can be avoided, thereby reducing the probability of film formation on the side of the wafer. It also improves the cleanliness of the wafer itself caused by film formation on the side of the wafer in the prior art, as well as the cleanliness of the process chamber and subsequent transmission channels accumulated over a long period of time, thereby improving the stability of the overall wafer process and ensuring the process quality of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 is a schematic structural diagram of a device for improving film formation on the side of a wafer provided in this embodiment;

[0017] Figure 2 This is one of the barrier principle diagrams of the barrier structure of the device for improving the film formation on the side of the wafer provided in this embodiment;

[0018] Figure 3 Schematic diagram of the heating plate structure of the device for improving film formation on the side of a wafer provided in this embodiment;

[0019] Figure 4 It is a schematic diagram of the heating plate and wafer structure of the device for improving film formation on the side of the wafer provided in this embodiment;

[0020] Figure 5 This is the second diagram of the barrier structure principle of the device for improving the film formation on the side of the wafer provided in this embodiment;

[0021] Figure 6 This is a schematic structural diagram of a first embodiment of a barrier structure of a device for improving film formation on the side of a wafer provided in this embodiment;

[0022] Figure 7 This is a schematic structural diagram of Embodiment 2 of the barrier structure of the device for improving film formation on the side of a wafer provided in this embodiment;

[0023] Figure 8 It is a schematic diagram of the barrier structure and wafer coordination of the device for improving film formation on the side of the wafer provided in this embodiment.

[0024] Icons: 10-process chamber; 11-heating plate; 110-receiving groove; 110a-groove wall; 12-spray upper plate; 13-barrier structure; 130-barrier part; 1301-first barrier part; 1302-second barrier part; 1303-connecting part; 131-barrier foot; 1311-first surface; 1312-second surface; 132-card slot; 20-wafer; a-first angle; b-second angle; d-thickness; t-gap. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0026] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0027] It should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0028] In the existing wafer film formation process, when the cumulative film thickness deposited on the wafer surface is greater than 5μm, especially when the film thickness is between 5um and more than ten um, film formation is easy to occur on the side of the wafer, and the film on the side of the wafer appears in the form of film flocs; after a period of time, the film flocs on the side of the wafer will cause wafer surface cleanliness problems, affecting PA performance.

[0029] In view of this, in order to solve the cleanliness problem of film formation on the side of the wafer, the embodiment of the present application provides a device for improving film formation on the side of the wafer, which can better improve the film formation on the side of the wafer, optimize the PA performance, and ensure the stability of the process. At the same time, it can also realize the development of thin film processes of different thicknesses using the same set of hardware, saving process time.

[0030] For details, please refer to Figure 1 As shown, the device for improving the film formation on the side of the wafer provided by the embodiment of the present application includes a process chamber 10, a heating plate 11 is arranged in the process chamber 10, the heating plate 11 is used to place the wafer 20, and a spray upper plate 12 is also arranged above the heating plate 11. The process gas is introduced toward the top of the wafer 20 through the spray upper plate 12 to form a film on the surface of the wafer 20. The side of the heating plate 11 is provided with a barrier structure 13 to prevent the process gas from forming a film on the side of the wafer 20.

[0031] The process of forming a film by vapor deposition is carried out in the process chamber 10, and the heating plate 11 is used to place the wafer 20. In one embodiment, the heating plate 11 can also rotate, and a rotating shaft can be connected to the bottom of the heating plate 11. The heating plate 11 is driven to rotate by the rotating shaft, and the bottom of the heating plate 11 also heats the wafer 20; at the same time, a spray upper plate 12 is arranged above the wafer 20, and the spray upper plate 12 sprays process gas toward the upper surface of the wafer 20, so that a film layer can be formed on the surface of the wafer 20.

[0032] In order to avoid film formation on the side of the wafer 20 , the present application also sets a barrier structure 13 on the side of the heating plate 11 . The barrier structure 13 can prevent the process gas from contacting the side of the wafer 20 , thereby avoiding the formation of a film layer on the side of the wafer 20 .

[0033] In addition, the material of the barrier structure 13 can be ceramic material, sapphire, etc., which is conducive to blocking process gases and does not affect the film forming process.

[0034] Therefore, the device for improving the film formation on the side of the wafer provided in the embodiment of the present application, by arranging a heating plate 11 in the process chamber 10 and arranging a spray upper plate 12 above the heating plate 11, when the spray upper plate 12 sprays the process gas toward the wafer 20 on the heating plate 11, a film layer can be formed on the surface of the wafer 20; and in order to avoid the formation of a film layer on the side of the wafer 20, a barrier structure 13 is arranged on the side of the heating plate 11, and the function of the barrier structure 13 is to prevent the process gas from contacting the side of the wafer 20. In this way, the situation where the process gas contacts the side of the wafer 20 and forms a film on the side of the wafer 20 can be avoided, thereby reducing the probability of film formation on the side of the wafer 20, and also improving the cleanliness of the wafer 20 itself caused by the film formation on the side of the wafer 20 in the prior art, as well as the cleanliness problems of the process chamber 10 and the subsequent transmission channels accumulated due to long-term processes, thereby improving the stability of the overall process of the wafer 20 and ensuring the process quality of the wafer 20.

[0035] Further, as shown in Figure Figure 2 , Figure 3 , Figure 4 As shown, a receiving groove 110 is formed on the surface of the heating plate 11, and the wafer 20 is arranged in the receiving groove 110. An inclination is provided between the groove wall 110a of the receiving groove 110 and the horizontal plane, and a gap t is formed between the side of the wafer 20 and the groove wall 110a of the receiving groove 110. The blocking structure 13 includes a blocking foot 131 extending into the gap t, and a blocking part 130 connected to the blocking foot 131 and arranged on the side of the heating plate 11.

[0036] The wafer 20 is accommodated in the accommodating groove 110 of the heating plate 11, and the groove wall 110a of the accommodating groove 110 is an inclined surface. After the wafer 20 is accommodated therein, the side surface of the wafer 20 and the inclined groove wall 110a of the accommodating groove 110 can form a gap t; since the side surface of the wafer 20 is generally a vertical surface, perpendicular to the groove bottom of the accommodating groove 110, the gap t formed by the side surface of the wafer 20 and the groove wall 110a of the accommodating groove 110 is a triangular gap t.

[0037] When the wafer 20 is film-formed, the process gas can easily enter the gap t to contact the side of the wafer 20, so that a film layer is formed on the side of the wafer 20. To improve this situation, the barrier foot 131 of the barrier structure 13 of the present application extends into the gap t to fill the position of the gap t, so that the process gas cannot contact the side of the wafer 20, thus solving the problem of film formation on the side of the wafer 20.

[0038] In order to fix the barrier structure 13 on the heating plate 11, the barrier foot 131 extending into the gap t is also connected to the barrier part 130. The barrier part 130 is located on the side of the heating plate 11 and is clamped with the heating plate 11. The barrier structure 13 and the heating plate 11 form a split structure, which is convenient for replacing different barrier structures 13 to adapt to gaps t of different sizes and dimensions (different gaps t are formed when the size of the wafer 20 and the film thickness requirements are different). This allows one set of equipment to develop processes for thin films of different thicknesses, facilitates mass production, and saves process time and cost.

[0039] How does the blocking foot 131 achieve matching with the gap t and blocking the process gas? Specifically, Figure 5 As shown, the blocking foot 131 has a first surface 1311 close to the groove wall 110a and a second surface 1312 close to the wafer 20, a first angle a matching the inclination angle is formed between the first surface 1311 and the horizontal plane, and a second angle b is formed between the second surface 1312 and the horizontal plane.

[0040] As mentioned above, the gap t is generally a triangular gap t. To fill the gap t, the blocking foot 131 is also matched into a triangle. Two surfaces of the triangular blocking foot 131 extend into the triangular gap t to respectively match with two corresponding surfaces of the triangular gap t.

[0041] Specifically, one surface of the blocking foot 131 is close to the groove wall 110a of the accommodating groove 110 and is in contact with the groove wall 110a, which is referred to as the first surface 1311. The first surface 1311 and the horizontal plane form a first angle a. In order to make the first surface 1311 of the blocking foot 131 match and fit with the groove wall 110a, the angle of the first angle a is the same as the inclination angle of the groove wall 110a.

[0042] Generally, the first angle a is between 30° and 40°, that is, the inclination angle of the groove wall 110a is also between 30° and 40°, so that after the blocking foot 131 is inserted into the gap t, the first surface 1311 of the blocking foot 131 and the groove wall 110a can be firmly fitted to ensure the stability of the blocking foot 131 filling the gap t.

[0043] On the other hand, the other side of the blocking foot 131 is close to the side wall of the wafer 20 and may or may not be in contact with the side wall of the wafer 20, which is called the second side 1312. The second side 1312 and the horizontal plane form a second angle b. When the second angle b is in an ideal state of 90°, that is, the second side 1312 is vertically arranged, the blocking foot 131 formed in this case just fills the gap t, the second side 1312 of the blocking foot 131 is parallel to and in contact with the side of the wafer 20, and the first side 1311 of the blocking foot 131 is in contact with the groove wall 110a. Due to the obstruction of the blocking foot 131, the process gas cannot enter the gap t and cannot contact the side of the wafer 20, and thus cannot form a film on the side of the wafer 20.

[0044] However, in actual processes, due to various reasons, such as factors such as the placement of the wafer 20, it is not possible to completely fit the side surface of the wafer 20 with the second surface 1312 of the blocking foot 131, so the angle of the second angle b varies according to actual needs. For example, the second angle b is between 30° and 90°. In this way, the blocking foot 131 can fill the gap t, but not completely fill the gap t. Figure 5 As shown, there is a small gap between the side of the wafer 20 and the second surface 1312 of the blocking foot 131. Although the process gas can also enter the small gap, compared with the gap t through which the process gas directly enters the large space, the harm of film formation on the side of the wafer 20 caused by the small gap is far lower than that of the existing technology. Therefore, the probability of film formation on the side of the wafer 20 is greatly reduced.

[0045] In addition, as mentioned above, in order to fix the blocking foot 131 , a blocking portion 130 connected to the blocking foot 131 is further provided on the side of the heating plate 11 , and the thickness d of the blocking portion 130 may generally be between 0.5 mm and 2 mm.

[0046] This application provides three different embodiments of the barrier structure 13 for illustration; in the first embodiment, Figure 6 As shown, the blocking portion 130 includes a first blocking portion 1301 and a second blocking portion 1302 arranged in parallel, and a connecting portion 1303 connecting the first blocking portion 1301 and the second blocking portion 1302 to form a semi-enclosed structure wrapped around the side of the heating plate 11, the first blocking portion 1301 is located on the side of the heating plate 11 accommodating the wafer 20, and the blocking foot 131 is connected to the side of the first blocking portion 1301 close to the wafer 20.

[0047] In this way, the first barrier part 1301, the connecting part 1303 and the second barrier part 1302 are connected in sequence to form a "]"-like structure. Through this semi-closed structure, it is clamped on the side edge of the heating plate 11, and the blocking foot 131 is connected to the first barrier part 1301 located above and extends into the gap t.

[0048] On this basis, in the second embodiment, Figure 7 As shown, the inner wall of the connecting portion 1303 close to the heating plate 11 is further provided with a clamping groove 132. The blocking structure 13 is firmly clamped with the side surface of the heating plate 11 through the clamping groove 132.

[0049] In the third embodiment, the blocking portion 130 is a circular ring, which is located on one side of the heating plate 11 accommodating the wafer 20 , and the blocking foot 131 is connected to the side of the circular ring close to the wafer 20 .

[0050] The barrier structure 13 is a circular ring as a whole, and the bottom of the inner ring of the circular ring is connected to the barrier foot 131 to extend into the gap t; Figure 8 The middle dotted circle is the gap t into which the blocking foot 131 extends.

[0051] The barrier structure 13 is not limited to a single embodiment, but can also be a combination of several embodiment structures; it can be seen from the above three embodiments that the barrier structure 13 can be a semi-enclosed structure in the first and second embodiments, and the barrier structure 13 can be regarded as a three-dimensional structure with an angle of 180°; the barrier structure 13 can also be a circular ring structure in the third embodiment, and the barrier structure 13 can be regarded as a plane structure with an angle of 0°; in addition, the overall shape angle of the barrier structure 13 can also be a structural member between 0° and 180°, which is specifically determined according to the shape matching of the actual heating plate 11.

[0052] In summary, the device for improving the film formation on the side of the wafer provided in the embodiment of the present application designs the corresponding slope (the second angle b), shape angle and thickness d of the split barrier structure 13 according to the edge morphology of different wafers 20, reduces the probability of the existence of plasma to reduce the probability of film formation on the side of the wafer 20, thereby improving the problem of film growth on the side of the wafer 20 and the cleanliness problem of the chamber and the transmission channel accumulated due to long-term process accumulation. At the same time, it can also realize the development of thin film processes of different thicknesses with the same set of equipment, saving time; it can also improve the problem of film growth on the side of the wafer 20 by combining not only one barrier structure 13 according to different positions, and the specific settings can be selected according to needs, which will not be repeated here.

[0053] The above are only embodiments of the present application and are not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.

Claims

1. A device for improving film formation on the side of a wafer, It is characterized in that include: A process chamber, wherein a heating plate is arranged in the process chamber, the heating plate is used to place a wafer, a spray upper plate is also arranged above the heating plate, a process gas is introduced toward the top of the wafer through the spray upper plate to form a film on the surface of the wafer, a barrier structure is arranged on the side of the heating plate to prevent the process gas from contacting the side of the wafer to avoid film formation on the side of the wafer; a receiving groove is formed on the surface of the heating plate, the wafer is arranged in the receiving groove, an inclination angle is sandwiched between the groove wall of the receiving groove and the horizontal plane, the A gap is formed between the side of the wafer and the wall of the accommodating groove, and the blocking structure includes a blocking foot extending into the gap, and a blocking part connected to the blocking foot and arranged on the side of the heating plate; the blocking part includes a first blocking part and a second blocking part arranged in parallel, and a connecting part connecting the first blocking part and the second blocking part to form a semi-enclosed structure wrapped around the side of the heating plate, the first blocking part is located on the side of the heating plate accommodating the wafer, and the blocking foot is connected to the side of the first blocking part close to the wafer.

2. The device for improving film formation on the side of a wafer according to claim 1, It is characterized in that The blocking foot has a first surface close to the groove wall and a second surface close to the wafer, the first surface and the horizontal plane form a first angle matching the inclination angle, and the second surface and the horizontal plane form a second angle.

3. The device for improving film formation on the side of a wafer according to claim 2, It is characterized in that The first angle is between 30° and 40°.

4. The device for improving film formation on the side of a wafer according to claim 2, It is characterized in that The second angle is between 30° and 90°.

5. The device for improving film formation on the side of a wafer according to claim 1, It is characterized in that The thickness of the barrier portion is between 0.5 mm and 2 mm.

6. The device for improving film formation on the side of a wafer according to claim 1, It is characterized in that The inner wall of the connecting portion close to the heating plate is also provided with a slot.

7. The device for improving film formation on the side of a wafer according to claim 1, It is characterized in that The material of the barrier structure at least includes ceramic or sapphire.

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