Wafer non-photosensitive polyimide layer manufacturing method
By combining non-contact baking and edge washing processes with contact baking, the problem of polyimide material overflowing onto the heating plate was solved, ensuring the normal fabrication of the non-photosensitive polyimide layer on the wafer.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HUA HONG SEMICON WUXI LTD
- Filing Date
- 2022-07-25
- Publication Date
- 2026-06-02
AI Technical Summary
During the fabrication of the non-photosensitive polyimide layer, polyimide material overflows onto the heating plate, causing contamination of the heating plate and affecting subsequent wafer soft baking operations.
A non-contact baking and edge washing process is adopted, combined with a contact baking and back washing process, to remove the polyimide layer on the wafer edge and back side, avoiding overflow to the heating plate.
This effectively prevents polyimide material from overflowing onto the heating plate, ensuring the normal operation of subsequent wafer soft baking and avoiding contamination.
Smart Images
Figure CN115274470B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor integrated circuit technology, and specifically to a method for fabricating a non-photosensitive polyimide layer on a wafer. Background Technology
[0002] Non-photosensitive polyimide materials are widely used in semiconductor manufacturing packaging, coating and bonding materials due to their excellent high and low temperature resistance, electrical insulation, adhesion, radiation resistance and dielectric resistance, to form protective films for devices or as interlayer insulation layers for multilayer wiring.
[0003] In related technologies, when fabricating non-photosensitive polyimide layers, because the coated non-photosensitive polyimide has high viscosity and a thick thickness, it is necessary to first perform a soft baking operation on the wafer coated with non-photosensitive polyimide using a heating plate, and then perform edge washing and back washing processes.
[0004] However, when fabricating a non-photosensitive polyimide layer using this process, the polyimide material overflows onto the heating plate during the soft baking process, contaminating the heating plate and adversely affecting subsequent soft baking operations on other wafers. Summary of the Invention
[0005] This application provides a method for fabricating a non-photosensitive polyimide layer on a wafer, which can solve the problem in related technologies where polyimide overflows onto the heating plate during the fabrication of the non-photosensitive polyimide layer, contaminating the heating plate and adversely affecting subsequent soft baking operations on other wafers.
[0006] To address the technical problems described in the background art, this application provides a method for fabricating a non-photosensitive polyimide layer on a wafer, the method comprising the following steps performed sequentially:
[0007] A non-photosensitive polyimide layer is coated on the wafer;
[0008] The wafer coated with a non-photosensitive polyimide layer is baked non-contactly using a heating plate;
[0009] The wafer after the non-photosensitive polyimide layer has been cured is subjected to edge washing and back washing processes to remove the non-photosensitive polyimide layer near the edge of the wafer and located on the back side of the wafer.
[0010] The wafer is baked in contact with a heating plate to cure the non-photosensitive polyimide layer on the wafer.
[0011] Optionally, the step of performing non-contact baking of the wafer coated with a non-photosensitive polyimide layer using a heating plate includes:
[0012] Within a temperature range of 175°C to 185°C, wafers coated with a non-photosensitive polyimide layer are baked non-contactly using a heating plate.
[0013] Optionally, the step of performing non-contact baking of the wafer coated with a non-photosensitive polyimide layer using a heating plate includes:
[0014] Within a temperature range of 175°C to 185°C, wafers coated with a non-photosensitive polyimide layer are baked non-contactly for 160 to 170 seconds using a heating plate.
[0015] Optionally, the step of performing edge washing and back washing processes on the wafer after the non-photosensitive polyimide layer has been cured to remove the non-photosensitive polyimide layer near the wafer edge and located on the back side of the wafer includes:
[0016] The wafer with the non-photosensitive polyimide layer cured by using a methylpyrrolidone solution is subjected to edge washing and back washing processes to remove the non-photosensitive polyimide layer near the edge of the wafer and located on the back side of the wafer.
[0017] Optionally, the step of contact baking the wafer with a heating plate to cure the non-photosensitive polyimide layer on the wafer includes:
[0018] The wafer is subjected to contact baking via a heating plate within a temperature range of 115°C to 125°C, thereby curing the non-photosensitive polyimide layer on the wafer.
[0019] Optionally, the step of contact baking the wafer with a heating plate to cure the non-photosensitive polyimide layer on the wafer includes:
[0020] The wafer is subjected to contact baking for 175 to 185 seconds using a heating plate within a temperature range of 115 to 125 degrees Celsius, thereby curing the non-photosensitive polyimide layer on the wafer.
[0021] Optionally, the step of performing edge washing and back washing processes on the wafer after the non-photosensitive polyimide layer has been cured to remove the non-photosensitive polyimide layer near the wafer edge and located on the back side of the wafer includes:
[0022] This causes the wafer to rotate after the non-photosensitive polyimide layer has been cured.
[0023] Spray a cleaning solution onto the upper and lower surfaces of the wafer's edge to perform edge washing and back washing processes on the wafer after the non-photosensitive polyimide layer has been cured, removing the non-photosensitive polyimide layer near the wafer's edge and on the back of the wafer.
[0024] The technical solution of this application includes at least the following advantages: non-contact baking of the wafer coated with a non-photosensitive polyimide layer is performed by a heating plate; then, the wafer after the non-photosensitive polyimide layer has been cured is subjected to edge washing and back washing processes to remove the non-photosensitive polyimide layer near the edge of the wafer and located on the back of the wafer; then, contact baking of the wafer is performed by a heating plate to cure the non-photosensitive polyimide layer on the wafer, which can effectively prevent the polyimide material from overflowing onto the heating plate during the soft baking process, contaminating the heating plate, and causing adverse effects on the subsequent soft baking operations of other wafers. Attached Figure Description
[0025] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0026] Figure 1 A flowchart illustrating a method for fabricating a non-photosensitive polyimide layer on a wafer according to an embodiment of this application is shown.
[0027] Figure 2 A schematic diagram of an embodiment of non-contact baking of a wafer coated with a non-photosensitive polyimide layer using a heating plate is shown.
[0028] Figure 3 A schematic diagram is shown of the edge washing and back washing process for wafers after curing a non-photosensitive polyimide layer;
[0029] Figure 4 A schematic diagram of contact baking of the wafer via a heating plate in step S4 is shown. Detailed Implementation
[0030] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0032] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0033] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.
[0034] Figure 1 This illustration shows a flowchart of a method for fabricating a non-photosensitive polyimide layer on a wafer according to an embodiment of this application. Figure 1 As can be seen from the above, the method for fabricating the non-photosensitive polyimide layer of this wafer includes the following steps S1 to S4 performed sequentially:
[0035] Step S1: Coat a non-photosensitive polyimide layer on the wafer.
[0036] Step S2: Non-contact baking of the wafer coated with a non-photosensitive polyimide layer using a heating plate.
[0037] Reference Figure 2 It illustrates a schematic diagram of an embodiment of non-contact baking of a wafer coated with a non-photosensitive polyimide layer via a heating plate, from... Figure 2 As can be seen, the wafer 200 coated with a non-photosensitive polyimide layer can be lifted from the heating plate 300 by the support foot 100, so that the wafer 200 coated with the non-photosensitive polyimide layer avoids contact with the heating plate 300.
[0038] Optionally, the wafer coated with a non-photosensitive polyimide layer can be baked non-contactly for 160 to 170 seconds using a heating plate within a temperature range of 175 to 185 degrees Celsius, so that the non-photosensitive polyimide layer on the wafer is basically cured and no overflow problem will occur subsequently.
[0039] Step S3: Perform edge washing and back washing processes on the wafer after the non-photosensitive polyimide layer has been cured to remove the non-photosensitive polyimide layer near the edge of the wafer and on the back side of the wafer.
[0040] Reference Figure 3 It shows a schematic diagram of the edge washing and back washing process for wafers after the non-photosensitive polyimide layer has been cured. Figure 3 As can be seen, the wafer 200 after the non-photosensitive polyimide layer is cured is placed on the rotating stage 400, and the nozzles 500 are located on the upper and lower sides of the edge of the wafer 200, which can spray the cleaning liquid onto the upper and lower surfaces of the edge of the wafer 200. The wafer is rotated by the rotating stage 400 to realize the edge cleaning and back cleaning operations of the wafer 200.
[0041] Optionally, when performing edge washing and back washing processes on the wafer after the non-photosensitive polyimide layer has been cured to remove the non-photosensitive polyimide layer near the wafer edge and located on the back of the wafer, a methylpyrrolidone solution can be used to perform edge washing and back washing processes on the wafer after the non-photosensitive polyimide layer has been cured to remove the non-photosensitive polyimide layer near the wafer edge and located on the back of the wafer.
[0042] Step S4: The wafer is baked in contact with a heating plate to cure the non-photosensitive polyimide layer on the wafer.
[0043] Reference Figure 4 It shows a schematic diagram of contact baking of the wafer by a heating plate in step S4.
[0044] from Figure 4 As can be seen, the wafer 200, after completing the edge washing and back washing operations, is placed on the heating plate 600 and directly contacts the heating plate 600 for contact baking, so that the non-photosensitive polyimide layer on the wafer 200 is completely cured.
[0045] Optionally, the wafer can be contact-baked for 175 to 185 seconds using a heating plate within a temperature range of 115 to 125 degrees Celsius to cure the non-photosensitive polyimide layer on the wafer. When baking the wafer again in step S4, a different heating plate than in step S2 is used to avoid the problem of switching heating temperatures and affecting work efficiency due to using the same heating plate.
[0046] In this embodiment, the wafer coated with a non-photosensitive polyimide layer is first baked non-contactly using a heating plate; then, the wafer after the non-photosensitive polyimide layer has been cured undergoes edge washing and back washing processes to remove the non-photosensitive polyimide layer near the wafer edge and on the back of the wafer; finally, the wafer is baked in contact using a heating plate to cure the non-photosensitive polyimide layer on the wafer. This effectively prevents polyimide material from overflowing onto the heating plate during the soft baking process, contaminating the heating plate, and causing adverse effects on subsequent soft baking operations of other wafers.
[0047] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this application.
Claims
1. A method for fabricating a non-photosensitive polyimide layer on a wafer, characterized in that, The method for fabricating the non-photosensitive polyimide layer of the wafer includes the following steps performed in sequence: A non-photosensitive polyimide layer is coated on the wafer; Within a temperature range of 175°C to 185°C, wafers coated with a non-photosensitive polyimide layer are baked non-contactly using a heating plate. The wafer after the non-photosensitive polyimide layer has been cured is subjected to edge washing and back washing processes to remove the non-photosensitive polyimide layer near the edge of the wafer and located on the back side of the wafer. The wafer is subjected to contact baking via a heating plate within a temperature range of 115°C to 125°C, thereby curing the non-photosensitive polyimide layer on the wafer.
2. The method for fabricating a non-photosensitive polyimide layer on a wafer as described in claim 1, characterized in that, The step of non-contact baking the wafer coated with a non-photosensitive polyimide layer using a heating plate includes: Within a temperature range of 175°C to 185°C, wafers coated with a non-photosensitive polyimide layer are baked non-contactly for 160 to 170 seconds using a heating plate.
3. The method for fabricating a non-photosensitive polyimide layer on a wafer as described in claim 1, characterized in that, The step of performing edge washing and back washing processes on the wafer after curing the non-photosensitive polyimide layer to remove the non-photosensitive polyimide layer near the wafer edge and located on the back side of the wafer includes: The wafer with the non-photosensitive polyimide layer cured by using a methylpyrrolidone solution is subjected to edge washing and back washing processes to remove the non-photosensitive polyimide layer near the edge of the wafer and located on the back side of the wafer.
4. The method for fabricating a non-photosensitive polyimide layer on a wafer as described in claim 1, characterized in that, The step of contact baking the wafer with a heating plate to cure the non-photosensitive polyimide layer on the wafer includes: The wafer is subjected to contact baking for 175 to 185 seconds using a heating plate within a temperature range of 115 to 125 degrees Celsius, thereby curing the non-photosensitive polyimide layer on the wafer.
5. The method for fabricating a non-photosensitive polyimide layer on a wafer as described in claim 1, characterized in that, The step of performing edge washing and back washing processes on the wafer after curing the non-photosensitive polyimide layer to remove the non-photosensitive polyimide layer near the wafer edge and located on the back side of the wafer includes: This causes the wafer to rotate after the non-photosensitive polyimide layer has been cured. Spray a cleaning solution onto the upper and lower surfaces of the wafer's edge to perform edge washing and back washing processes on the wafer after the non-photosensitive polyimide layer has been cured, removing the non-photosensitive polyimide layer near the wafer's edge and on the back of the wafer.