Wafer processing technology, gluing and developing equipment and wafer processing system

Abstract

The invention provides a wafer processing technology, a gluing and developing device and a wafer processing system.The wafer processing technology comprises the following steps that S1, photoresist coating technology processing is conducted on the front face of a wafer; s2, cleaning the back surface of the wafer to remove pollutants on the back surface of the wafer; s3, coating the back surface of the wafer with a smooth film layer; s4, carrying out photoetching process treatment on the front surface of the wafer; s5, performing development process treatment on the front surface of the wafer; by adding the process step of coating the smooth film layer on the back surface of the wafer, the smooth film layer can be formed on the back surface of the wafer, and the smooth film layer can effectively reduce the friction force when a bearing table of a photoetching machine adsorbs the wafer, so that the wafer can be smoothly expanded in the adsorption and flattening process, and a minimum overlay error is finally realized; furthermore, the friction force generated when the photoetching machine bearing table adsorbs the wafer is effectively reduced, so that the abrasion of the photoetching machine bearing table can be reduced, and the maintenance cost of the photoetching machine can be greatly reduced.

Description

Technical Field

[0001] The present invention relates to the field of wafer processing technology and wafer processing equipment, and in particular to a wafer processing technology, glue coating and developing equipment and a wafer processing system. Background Art

[0002] In wafer manufacturing, the coating and developing equipment is a key processing equipment in the integrated circuit chip manufacturing process. It is often operated online with the photolithography machine to complete the wafer photoresist coating, curing, post-exposure baking, developing, hardening and other processes. The quality of its architecture design directly affects the equipment's production capacity, stability, operation and maintenance convenience, and cost control.

[0003] In the chip manufacturing process, keeping the back of the wafer clean is very important for the photolithography process. When the back of the wafer is contaminated by particles, it will wear the carrier of the photolithography machine, thereby increasing the maintenance cost and maintenance time of the photolithography machine, and seriously reducing the chip yield. Therefore, how to improve the cleanliness of the wafer back before photolithography is an important process. The commonly used method at present is to set a back washing unit inside the coating and developing equipment to clean the wafer back before the photolithography process. The cleaning tool usually adopts diamond grinding + physical cleaning, which can not only clean up the particles generated by the previous process in the coating and developing equipment, but also clean up the wafer back particles left by the previous equipment of the coating and developing equipment. However, diamond grinding will cause problems on the surface of the wafer back, such as local scratches and flatness changes, which will also damage the wafer and reduce the chip yield. Summary of the invention

[0004] The purpose of the present invention is to propose a wafer processing technology, a coating and developing device and a wafer processing system to solve the technical problem of how to reduce the friction force when the photolithography machine carrier adsorbs the wafer, thereby reducing the wear of the photolithography machine carrier.

[0005] To achieve the above object, a first aspect of the present invention provides a wafer processing process, which includes the following steps: S1. Performing a photoresist coating process on the front side of the wafer; S2, cleaning the back side of the wafer to remove pollutants on the back side of the wafer; S3, coating a smooth film layer on the back side of the wafer; S4, performing photolithography process on the front side of the wafer; S5. Performing a development process on the front side of the wafer.

[0006] The technical effect achieved through the above-mentioned process steps is: by adding the process step of coating a smooth film layer on the back of the wafer, the smooth film layer can be formed on the back of the wafer, and the smooth film layer can effectively reduce the friction force when the lithography machine carrier adsorbs the wafer, thereby enabling the wafer to smoothly expand during the leveling process, and ultimately achieving extremely small overlay errors; further, by effectively reducing the friction force when the lithography machine carrier adsorbs the wafer, the wear of the lithography machine carrier can be reduced, thereby greatly reducing the maintenance cost of the lithography machine.

[0007] A further beneficial effect is that by coating the smooth film layer on the back of the wafer, static electricity on the back of the wafer can be effectively eliminated, preventing static electricity from corroding the photolithography machine carrier; A further benefit is that in step S2, the back side of the wafer is cleaned to remove contaminants on the back side of the wafer. Step S3 is arranged after step S2. The advantage of such an arrangement is that it can not only complete the coating of the smooth film layer on the back side of the wafer, but also prevent the smooth film layer from being destroyed by the process in step S2, thereby protecting the lithography machine carrier.

[0008] Preferably, step S3 comprises: S31, spraying a material for forming the smooth film layer onto the back side of the wafer, and simultaneously performing low-temperature baking on the back side of the wafer to form the smooth film layer.

[0009] The technical effect achieved through the above process steps is: while spraying the material used to form the smooth film layer on the back of the wafer, the back of the wafer is baked at a low temperature, which helps the formation of the smooth film layer and enables the smooth film layer to be stably and efficiently deposited on the back of the wafer.

[0010] Preferably, step S1 includes soft baking the wafer coated with photoresist; in step S31, the baking temperature during the low-temperature baking does not exceed the baking temperature during the soft baking in step S1.

[0011] Through the above process steps, the technical effect achieved is: in step S31, the baking temperature during the low-temperature baking is set to not exceed the baking temperature during the soft baking in step S1, which can avoid damaging the photoresist film thickness on the front side of the wafer when baking the back side of the wafer; thereby forming a smooth film layer while also ensuring the product yield.

[0012] Preferably, in step S31, the smooth film layer is formed on the back side of the wafer by vapor deposition.

[0013] Through the above process steps, the technical effect achieved is: the smooth film layer is formed on the back of the wafer by vapor deposition, which helps the material used to form the smooth film layer to be evenly deposited on the back of the wafer to form a thin smooth film layer.

[0014] Preferably, in step S31, the material used to form the smooth film layer is hexamethyldisilazane.

[0015] Through the above process steps, the technical effect achieved is: hexamethyldisilazane is used as the material for forming the smooth film layer, considering that hexamethyldisilazane has relatively stable chemical properties, is widely used in the semiconductor industry, and has relatively low cost, which is beneficial to saving wafer processing costs.

[0016] The second aspect of the present application provides a glue coating and developing device, which includes: a glue coating and developing process module, which is used to perform a photoresist coating process on the front side of the wafer, and is used to perform a developing process on the wafer after the photolithography process.

[0017] An interface module is connected to the coating and developing process module, and the interface module includes a back washing unit and a coating unit; the back washing unit is used to clean the back side of the wafer; the coating unit is used to coat a smooth film layer on the back side of the wafer.

[0018] Through the above scheme, the technical effect achieved is: by integrating the coating unit in the interface module of the coating and developing equipment, a smooth film layer can be coated on the back of the wafer. The smooth film layer can effectively reduce the friction force when the photolithography machine carrier absorbs the wafer, so that the wafer can be smoothly expanded during the absorption and leveling process, and finally achieve a very small overlay error; further, by effectively reducing the friction force when the photolithography machine carrier absorbs the wafer, the wear of the photolithography machine carrier can be reduced, and the maintenance cost of the photolithography machine can be greatly reduced; further, the smooth film layer can also effectively eliminate static electricity on the back of the wafer, prevent static electricity from corroding the photolithography machine carrier, and effectively extend the life of the photolithography machine carrier, thereby improving the overall life of the photolithography machine.

[0019] Preferably, the coating and developing equipment further includes a front washing robot; the front washing robot is arranged at the interface module, and the front washing robot is used to transfer the wafer processed by the back washing unit to the coating unit for processing.

[0020] Through the above scheme, the technical effect achieved is: by integrating the back washing unit and the coating unit in the interface unit, and setting the coating unit after the back washing unit, it is possible to complete the coating of the smooth film layer on the back side of the wafer, and avoid the smooth film layer being destroyed by the process of the back washing unit, thereby protecting the lithography machine carrier.

[0021] Preferably, the interface module also includes a cache unit and a back wash robot; wherein, the cache unit is arranged between the back wash unit and the coating unit, and the cache unit is used to temporarily store wafers; the back wash robot is arranged between the back wash unit and the cache unit, and the back wash robot is used to transfer the wafers from the back wash unit to the cache unit.

[0022] The above solution achieves the following technical effect: the cache unit is like a "reservoir" that can adjust the working differences between different units. This can avoid the entire production line from being stalled due to a short delay or failure of a unit, ensuring the continuity and stability of the production process.

[0023] Preferably, the interface module further comprises: a cooling unit, wherein the cooling unit is used for receiving the wafer from the coating unit and cooling the wafer.

[0024] The technical effect achieved by the above scheme is: by setting the cooling unit to receive the wafer from the coating unit and cooling the wafer, the wafer reaches a temperature suitable for the photolithography process, which is convenient for the next step of photolithography process.

[0025] The third aspect of the present application provides a wafer processing system, comprising: a photolithography device and a coating and developing device as described in the second aspect of the present invention. The coating and developing device is used to perform a photoresist coating process on a wafer; the photolithography device is used to perform a photolithography process on a wafer that has been subjected to a photoresist coating process in the coating and developing device; further, the coating and developing device is also used to perform a developing process on the wafer after the photolithography process.

[0026] Through the above scheme, the technical effect achieved is: the wafer processing system can not only realize the photoresist coating process, photolithography process and development process of the wafer by adopting the above-mentioned coating and development equipment, but also can coat a smooth film layer on the back of the wafer before the wafer is subjected to the photolithography process. The smooth film layer can effectively reduce the friction force when the photolithography machine carrier absorbs the wafer, so that the wafer can be smoothly expanded during the absorption and leveling process, and finally achieve a very small overlay error; further, by effectively reducing the friction force when the photolithography machine carrier absorbs the wafer, the wear of the photolithography machine carrier can be reduced, and the maintenance cost of the photolithography machine can be greatly reduced; further, the smooth film layer can also effectively eliminate the static electricity on the back of the wafer, prevent static electricity from corroding the photolithography machine carrier, and effectively extend the life of the photolithography machine carrier, thereby improving the overall life of the photolithography machine.

[0027] In summary, the beneficial effects of the present invention are as follows: the present invention adds a process of coating a smooth film layer on the back of the wafer in the process of coating and developing the wafer, and the smooth film layer is coated on the back of the wafer to reduce the friction force when the photolithography machine carrier absorbs the wafer, so that the wafer can be smoothly expanded during the absorption and leveling process, and finally achieves a very small overlay error; Furthermore, by reducing the friction force when the lithography machine carrier absorbs the wafer, the wear of the lithography machine carrier can be effectively reduced, thereby reducing the maintenance cost and maintenance time of the lithography machine; In addition, the process of coating the back of the wafer with a smooth film layer can also eliminate static electricity on the back of the wafer, preventing static electricity from corroding the lithography machine carrier, thereby increasing the life of the carrier and reducing the cost of using the lithography machine. Since the process treatment of the back washing unit will damage the smooth film layer on the back of the wafer, this scheme arranges the coating unit in the process behind the back washing unit. This can not only complete the process of coating the smooth film layer on the back of the wafer, but also avoid the smooth film layer being damaged by the back washing process, thereby protecting the lithography machine carrier. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is an overall flow chart of the wafer processing process in Example 1 of the present invention; Figure 2 It is a detailed flow chart of the wafer processing technology in Example 1 of the present invention; Figure 3 It is a schematic diagram of the top view of the structure of the glue coating and developing device in an embodiment of the present invention; Figure 4 It is a schematic top view of the cross-sectional structure of the glue coating and developing device in an embodiment of the present invention; Figure 5 for Figure 2 A magnified view of the interface module; Figure 6 It is a schematic structural diagram of a laminating unit according to an embodiment of the present invention.

[0029] Reference numerals: 1-Case module; 2-Gluing and developing process module; 3-Interface module; 31-back washing robot; 32-front washing robot; 33-interface robot; 34-back washing unit; 35-laminating unit; 36-caching unit; 37-cooling unit; 321-top cover; 322-bottom cover; 323-center spray hole; 324-edge spray hole; 325-heater; 326-support column; 327-gap; 4- Lithography equipment; 5- Wafer. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the usual meanings understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Unless otherwise specified, the "connection" described in this article can be a direct connection or an indirect connection, that is, a connection through an intermediate.

[0031] See also Figure 1 The first embodiment of the present invention provides a wafer processing process, which includes the following steps: S1. Performing a photoresist coating process on the front side of the wafer; S2, cleaning the back side of the wafer to remove pollutants on the back side of the wafer; S3, coating a smooth film layer on the back side of the wafer; S4, performing photolithography process on the front side of the wafer; S5. Performing a development process on the front side of the wafer.

[0032] In this embodiment, step S2 is called a backwashing process, and step S3 is called a laminating process. In the above process steps, by adding a process step of coating a smooth film layer on the back of the wafer, the smooth film layer can be formed on the back of the wafer, and the smooth film layer can effectively reduce the friction force when the photolithography machine carrier adsorbs the wafer, thereby enabling the wafer to smoothly expand during the leveling process, and ultimately achieving extremely small overlay error; further, by effectively reducing the friction force when the photolithography machine carrier adsorbs the wafer, the wear of the photolithography machine carrier can be reduced, thereby greatly reducing the maintenance cost of the photolithography machine.

[0033] Since static electricity may cause accelerated corrosion of the lithography machine workbench (this is well known to those skilled in the art and the principle will not be repeated here), this embodiment can effectively eliminate static electricity on the back of the wafer by coating the smooth film layer on the back of the wafer to prevent static electricity from corroding the lithography machine carrier.

[0034] See also Figure 2 In this embodiment, step S1 (i.e., performing a photoresist coating process on the front side of the wafer) specifically includes the following process steps: S11, pre-treating the wafer using hexamethyldisilazane (HMDS); S12, coating photoresist on the front side of the wafer; S13, performing soft baking on the wafer coated with the photoresist; S14, performing edge exposure on the wafer; Steps S11 to S14 are all prior arts in the art and well known to those skilled in the art, and will not be described in detail here.

[0035] In step S2, the back side of the wafer is cleaned (i.e., back washing process) to remove contaminants on the back side of the wafer. Step S3 is set after step S2. The advantage of such a setting is that it can not only complete the coating of the smooth film layer on the back side of the wafer, but also avoid the smooth film layer being destroyed by the process in step S2, thereby protecting the lithography machine carrier.

[0036] In step S3 of the present embodiment, the material for forming the smooth film layer is sprayed onto the back of the wafer, and the back of the wafer is baked at a low temperature to form the smooth film layer. In this process step, while the material for forming the smooth film layer is sprayed onto the back of the wafer, the back of the wafer is baked at a low temperature, which helps to form the smooth film layer, so that the smooth film layer is stably and efficiently deposited on the back of the wafer.

[0037] In this embodiment, step S1 includes soft baking the wafer coated with photoresist; in step S31, the baking temperature during low temperature baking does not exceed the baking temperature during soft baking (Soft bake) in step S1. In this process step, in step S31, the baking temperature during low temperature baking is set to not exceed the baking temperature during soft baking in step S1, which can avoid damaging the photoresist film thickness on the front side of the wafer when baking the back side of the wafer; thereby, while forming a smooth film layer, the product yield is also guaranteed.

[0038] In this embodiment, in step S31, the smooth film layer is formed on the back of the wafer by vapor deposition. In this process step, the smooth film layer is formed on the back of the wafer by vapor deposition, which helps the material used to form the smooth film layer to be uniformly deposited on the back of the wafer to form a thin smooth film layer.

[0039] In this embodiment, in step S31, the material used to form the smooth film layer is hexamethyldisilazane. In this process step, hexamethyldisilazane is used as the material for forming the smooth film layer because hexamethyldisilazane has relatively stable chemical properties, is widely used in the semiconductor industry, has relatively low cost, and is conducive to saving wafer processing costs.

[0040] It is worth mentioning that the material used to form the smooth film layer can also be other fluorine-based resin materials headed by PTFE (polytetrafluoroethylene).

[0041] See also Figure 2 In this embodiment, step S5 (i.e., performing a development process on the front side of the wafer) specifically includes the following steps: S51, baking the exposed wafer (i.e., post-baking); S52, spraying developer onto the side of the wafer coated with photoresist S53, baking the wafer surface sprayed with the developer (i.e., hard baking); S54, removing the smooth film layer coated on the back side of the wafer; S55, post-development inspection (i.e., quality inspection of the wafer); The purpose of setting step S54 is to avoid the influence of the smooth film layer on the subsequent processes.

[0042] Steps S51 to S53 and S55 are all prior arts in the art and well known to those skilled in the art, so they will not be described in detail here.

[0043] See also Figure 3-Figure 6 The second embodiment of the present application provides a coating and developing device, which is used in conjunction with a photolithography device 4. In this embodiment, the photolithography device 4 is a photolithography machine.

[0044] like Figure 3 As shown, the coating and developing equipment includes: The coating and developing process module 2 is used to perform a photoresist coating process on the front side of the wafer 5, and to perform a developing process on the wafer 5 after the photolithography process. Figure 6 As shown, the front side of wafer 5 refers to Figure 6 The side of wafer 5 facing upward, the back side of wafer 5 refers to Figure 6 The side of the wafer 5 faces downward.

[0045] The interface module 3 is connected to the coating and developing process module 2 , and includes a backwash unit (BS) 34 and a coating unit 35 ; wherein the backwash unit 34 is used to clean the back side of the wafer 5 ; and the coating unit (BACS) is used to coat a smooth film layer on the back side of the wafer 5 .

[0046] The film box module 1 is connected to the glue coating and developing process module 2. The film box module 1 is provided with a film feed loading port (not shown) and a film return loading port (not shown); the film feed loading port is used to store the wafer 5 to be moved to the glue coating and developing process module 2; the film return loading port is used to store the wafer 5 from the glue coating and developing process module 2.

[0047] In this embodiment, by integrating the coating unit 35 in the interface module 3 of the coating and developing device, a smooth film layer can be coated on the back of the wafer 5. The smooth film layer can effectively reduce the friction force when the photolithography machine carrier absorbs the wafer 5, thereby enabling the wafer 5 to smoothly expand during the absorption and leveling process, and finally achieving a very small overlay error; further, by effectively reducing the friction force when the photolithography machine carrier (not shown) in the photolithography equipment 4 absorbs the wafer 5, the wear of the photolithography machine carrier can be reduced, thereby greatly reducing the maintenance cost of the photolithography machine; further, the smooth film layer can also effectively eliminate static electricity on the back of the wafer 5, prevent static electricity from corroding the photolithography machine carrier, thereby effectively extending the life of the photolithography machine carrier, thereby improving the overall life of the photolithography machine.

[0048] See also Figure 4 , Figure 5 In this embodiment, the coating and developing device further includes a front washing robot 32 ; the front washing robot 32 is arranged in the interface module 3 , and the front washing robot 32 is used to transfer the wafer 5 processed by the back washing unit 34 to the coating unit 35 for processing.

[0049] In this embodiment, by integrating the back washing unit 34 and the coating unit 35 in the interface module 3, and arranging the coating unit 35 after the back washing unit 34, it is possible to complete the coating of the smooth film layer on the back side of the wafer 5, and prevent the smooth film layer from being damaged by the process of the back washing unit 34, thereby protecting the lithography machine carrier (not shown).

[0050] See also Figure 4 , Figure 5 In this embodiment, a further improvement is that the interface module 3 also includes: a cache unit (BF) 36 and a back washing robot 31; wherein the cache unit 36 ​​is arranged between the back washing unit 34 and the coating unit 35, and the cache unit 36 ​​is used to temporarily store the wafers; the back washing robot 31 is arranged between the back washing unit 34 and the cache unit 36, and the back washing robot 31 is used to transfer the wafer 5 from the back washing unit 34 to the cache unit 36.

[0051] In this embodiment, the cache unit 36 ​​is like a "reservoir" that can adjust the working differences between different units. This can avoid the entire production line from being stopped due to a short delay or failure of a unit, thereby ensuring the continuity and stability of the production process.

[0052] See also Figure 5In this embodiment, the interface module 3 further includes: a cooling unit 37, and the cooling unit (CPC) 37 is used to receive the wafer 5 from the coating unit 35 and cool the wafer 5. It is worth mentioning that the wafer transfer between the coating unit 35 and the cooling unit 37 is undertaken by the positive cleaning robot 32. In this embodiment, the cooling unit 37 is provided to receive the wafer 5 from the coating unit 35 and cool the wafer 5 so that the wafer 5 reaches a temperature suitable for the photolithography process, which is convenient for the next step of photolithography process (SCAN).

[0053] See also Figure 5 In this embodiment, the interface module 3 further includes an interface robot 33; the interface robot 33 is arranged at one side of the cooling unit 37, and is used to transfer the cooled wafer 5 from the cooling unit 37 to the photolithography device 4. In this embodiment, the setting of the interface robot realizes the automatic transfer of the cooled wafer 5 from the cooling unit 37 to the photolithography device 4.

[0054] In this embodiment, the coating unit 35 includes a process chamber for accommodating the wafer 5, and the process chamber includes: a spraying part for spraying a material for forming a smooth film layer onto the back side of the wafer 5; and a heating part for heating the back side of the wafer 5 to promote the material to form a smooth film layer on the back side of the wafer 5. In this embodiment, the material for forming a smooth film layer is coated on the back side of the wafer 5 by vapor deposition through the spraying part, which helps the material for forming a smooth film layer to be uniformly deposited on the back side of the wafer 5 to form a thin smooth film layer.

[0055] Furthermore, the coating and developing module includes a liquid treatment module and a heat treatment module, and the heat treatment module is provided with a film removal unit (not shown), and the film removal unit is used to remove the smooth film layer coated on the back side of the wafer.

[0056] Furthermore, the process chamber includes a top cover 321 and a bottom cover 322, wherein the top cover 321 is disposed above the bottom cover 322; the top cover 321 and the bottom cover 322 are disposed opposite to each other and cooperate to form a process chamber; the wafer 5 is placed horizontally in the process chamber. The spraying part and the heating part are both disposed on the bottom cover 322 and face the back of the wafer 5.

[0057] In this embodiment, the spraying part includes a central spraying hole 323 and an edge spraying hole 324; wherein the central spraying hole 323 is used to spray the material for forming a smooth film layer to the center of the back of the wafer 5; and the edge spraying hole 324 is used to spray the material for forming a smooth film layer to the edge of the back of the wafer 5. In this embodiment, by respectively providing the central spraying hole 323 and the edge spraying hole 324 in the spraying part, two spraying methods of spraying to the center of the back of the wafer 5 and spraying to the edge of the back of the wafer 5 are realized, which helps to deposit the material for forming a smooth film layer more evenly on the back of the wafer 5.

[0058] In this embodiment, the heating portion includes a plurality of heaters 325, and the heaters 325 are arranged at equal intervals around the heating portion. In this embodiment, by providing a plurality of heaters 325 in the heating portion and arranging the heaters 325 at equal intervals around the heating portion, it is beneficial to evenly bake and heat the back side of the wafer 5, thereby making the smooth film layer formed on the back side of the wafer 5 more uniform.

[0059] Specifically, the central spray hole 323 is arranged at the center of the bottom cover 322, and there is one central spray hole 323; there are multiple edge spray holes 324, and the multiple edge spray holes 324 are arranged at equal intervals around the edge of the bottom cover 322. Further, multiple heaters 325 are arranged on the bottom cover 322 at equal intervals around the circumference.

[0060] Furthermore, a plurality of support columns 326 for supporting the wafer 5 are provided on the bottom cover 322. Under the support of the support columns, a gap 327 is formed between the wafer 5 and the bottom cover 322. After the material for forming the smooth film layer is sprayed out from the central spray hole 323 and the edge spray hole 324, it enters the gap 327 and is deposited on the back of the wafer 5 by vapor deposition.

[0061] In this embodiment, the coating unit 35 includes a supply part (not shown), which is used to provide the spraying part with materials for forming a smooth film layer; the central spraying hole 323 and the edge spraying hole 324 are both connected to the supply part.

[0062] In this embodiment, by providing a supply unit, the material for forming a smooth film layer is continuously supplied to the spraying unit, thereby ensuring the stability and continuity of the operation of the coating unit 35 .

[0063] In this embodiment, the material used to form the smooth film layer is gaseous hexamethyldisilazane.

[0064] See also Figure 4 , Figure 5 The third embodiment of the present application provides a wafer processing system, comprising: a photolithography device 4 and a coating and developing device as described in the first aspect of the present invention.

[0065] Among them, the coating and developing equipment is used to perform photoresist coating process on the wafer 5; the photolithography equipment 4 is used to perform photolithography process on the wafer 5 after the photoresist coating process in the coating and developing equipment; the coating and developing equipment is also used to perform development process on the wafer 5 after the photolithography process.

[0066] Through the above scheme, the technical effect achieved is: the wafer 5 processing system can not only realize the photoresist coating process, photolithography process and development process of the wafer 5 by adopting the above-mentioned coating and developing equipment, but also can coat a smooth film layer on the back of the wafer 5 before the photolithography process of the wafer 5. The smooth film layer can effectively reduce the friction force when the photolithography machine carrier absorbs the wafer 5, so that the wafer 5 can be smoothly expanded during the absorption and leveling process, and finally achieve a very small overlay error; further, by effectively reducing the friction force when the photolithography machine carrier absorbs the wafer 5, the wear of the photolithography machine carrier can be reduced, and the maintenance cost of the photolithography machine can be greatly reduced; further, the smooth film layer can also effectively eliminate the static electricity on the back of the wafer 5, prevent the static electricity from corroding the photolithography machine carrier, and effectively extend the life of the photolithography machine carrier, and thus improve the overall life of the photolithography machine.

[0067] In summary, the present invention proposes a wafer processing technology. By adding a process step of coating a smooth film layer on the back of the wafer to the wafer processing technology of the prior art, a smooth film layer can be formed on the back of the wafer. The smooth film layer can effectively reduce the friction force when the photolithography machine carrier adsorbs the wafer, thereby achieving extremely small overlay errors, effectively reducing the friction force when the photolithography machine carrier adsorbs the wafer, and thus greatly reducing the maintenance cost of the photolithography machine. On this basis, a coating and developing device is proposed. By integrating a coating unit in the interface module of the coating and developing device, a process of coating a smooth film layer on the back of the wafer is realized; on this basis, a wafer processing system is further proposed to realize the above-mentioned wafer processing technology. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has a high industrial utilization value.

[0068] The above is only a specific implementation of the embodiment of the present application, but the protection scope of the embodiment of the present application is not limited thereto, and any changes or replacements within the technical scope disclosed in the embodiment of the present application should be included in the protection scope of the embodiment of the present application. Therefore, the protection scope of the embodiment of the present application should be based on the protection scope of the claims.

Claims

1. A wafer processing process, characterized in that: The steps include: S1. Performing a photoresist coating process on the front side of the wafer; S2, cleaning the back side of the wafer to remove pollutants on the back side of the wafer; S3, coating a smooth film layer on the back side of the wafer; S4, performing photolithography process on the front side of the wafer; S5. Performing a development process on the front side of the wafer.

2. The wafer processing process according to claim 1, characterized in that: Step S3 includes: S31, spraying the material for forming the smooth film layer onto the back side of the wafer, and simultaneously performing low-temperature baking on the back side of the wafer to form the smooth film layer.

3. The wafer processing process according to claim 2, characterized in that: Step S1 includes soft baking the wafer coated with photoresist; in step S31, the baking temperature during the low-temperature baking does not exceed the baking temperature during the soft baking in step S1.

4. The wafer processing process according to claim 3, characterized in that: In step S31, the smooth film layer is formed on the back side of the wafer by vapor deposition.

5. The wafer processing process according to any one of claims 2 to 4, characterized in that: In step S31, the material used to form the smooth film layer is hexamethyldisilazane.

6. A coating and developing device, characterized in that: include: A coating and developing process module, used for performing a photoresist coating process on the front side of the wafer, and for performing a developing process on the wafer after the photolithography process; An interface module connected to the coating and developing process module, the interface module comprising a backwash unit and a laminating unit; The back washing unit is used for cleaning the back side of the wafer; and the coating unit is used for coating a smooth film layer on the back side of the wafer.

7. The coating and developing device according to claim 6, characterized in that: Also includes: A forward cleaning robot is arranged in the interface module, and is used for transferring the wafer processed by the back cleaning unit to the coating unit for processing.

8. The coating and developing device according to claim 7, characterized in that: The interface module also includes: A cache unit, disposed between the backwash unit and the laminating unit, and used for temporarily storing wafers; A back-wash robot is disposed between the back-wash unit and the cache unit, and is used for transferring the wafer from the back-wash unit to the cache unit.

9. The coating and developing device according to claim 6 or 7, characterized in that: The interface module further includes a cooling unit, which is used to receive the wafer from the coating unit and perform cooling processing on the wafer.

10. A wafer processing system, characterized in that: include: The coating and developing device according to any one of claims 6 to 9, used for performing a photoresist coating process on a wafer; A photolithography device, used for performing a photolithography process on the wafer after the photoresist coating process in the coating and developing device; The glue coating and developing equipment is also used to perform a developing process on the wafer after the photolithography process.

Images