Full-automatic coating process method for irregular area on surface of silicon wafer

Abstract

The application discloses a kind of full-automatic coating process methods of silicon wafer surface special-shaped area, comprising the following steps: template establishment, position identification, generate picture, coating data generation, data transmission, coating process control;Through the etching process is combined with visual positioning platform, RIP printing driver, UV inkjet technology, PLC process control and multithreading control technology, realizes the liquid photoresist direct spraying of 40nm chip to be etched special-shaped area, omits the process of processing photomask, directly sprays photoresist to the point position needing protection, effectively improves chip etching key process, improves chip manufacturing efficiency, reduces chip manufacturing cost.

Description

Technical Field

[0001] This invention relates to the field of chip manufacturing, and specifically to a fully automated coating process for irregularly shaped areas on the surface of a silicon wafer. Background Technology

[0002] Currently, in the photolithography process of chip manufacturing, a layer of photoresist is first coated onto the surface of the silicon wafer, and then a photomask is placed on it for area selection. Exposure is then used to dissolve the positive photoresist or solidify the negative photoresist outside the mask area, thus enabling the selection of irregularly shaped areas for chip etching. Therefore, the shape of the photomask determines the shape of the irregularly shaped area. The photomask uses a quartz substrate and requires complex processes such as photoresist coating, photolithography, measurement, and repair, resulting in limited usability and high costs. Therefore, this invention proposes a highly efficient, low-cost, and simple fully automated coating process for irregularly shaped areas on the silicon wafer surface. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention provides a fully automated coating process for irregular areas on silicon wafers, which directly sprays liquid photoresist onto irregular areas to be etched on 40nm chips, eliminating the mask exposure manufacturing step in traditional chip manufacturing processes, effectively improving key chip etching processes, simplifying chip manufacturing steps, and improving manufacturing efficiency.

[0004] Technical solution

[0005] A fully automated coating process for irregularly shaped areas on a silicon wafer surface includes the following steps:

[0006] Step 1: Template creation;

[0007] Step two, location identification;

[0008] Step 3: Generate the image;

[0009] Step 4: Coating data generation;

[0010] Step 5, data transmission;

[0011] Step six, coating process control.

[0012] Furthermore, the template creation mentioned in step one:

[0013] ① First, select a silicon wafer whose surface has been coated and fix it on top of the fixture. The fixture is rectangular in shape, and circular Mark points are set in the four right-angled areas of the fixture.

[0014] ② Place the fixture with the silicon wafer fixed on the worktable, and the control system captures images of the fixture with the silicon wafer fixed in real time. Select the Mark point area of ​​the fixture diagonally, identify the Mark point image, obtain the center position of the Mark point image, and save the Mark point image.

[0015] ③ Based on the image of the coated area presented by the computer, plot points along the coated area, construct the outline of the coated area using NURBS curves, manually adjust the position of each plotting point to achieve accurate fitting of the outline of the coated area, establish the relative positional relationship between the center of the Mark point and each point of the outline of the coated area, and complete the template creation.

[0016] Furthermore, in step two, the position identification involves placing the fixture with the uncoated silicon wafer fixed on it onto the worktable. The control system captures images of the fixture with the silicon wafer fixed in real time, retrieves the Mark point template image, identifies the Mark point position diagonally, compares it with the Mark point position of the template in step one, calculates the position deviation, and adjusts the contour of the coated area obtained in step one based on the position deviation to obtain the contour position of the irregular area on the surface of the current silicon wafer.

[0017] Furthermore, in step three, the image generation involves: setting a corresponding area in the computer memory based on the size of the workbench surface; using the GDI drawing method to set the image background and precision; drawing the corresponding outline in memory based on the irregular area outline obtained in step two; setting the pen color; filling the area enclosed by the corresponding outline; and saving it as a BMP format file to generate the printable image.

[0018] Further, in step four, the coating data is generated by performing color separation and binarization on the BMP image file generated in step three, and then using the ESC printing command to generate a printer instruction file.

[0019] Furthermore, in step five, the data transmission involves using the USB communication transmission protocol to send the generated printer instruction file to the printer, thereby realizing print data transmission.

[0020] Furthermore, in step six, the coating process control involves the control system detecting the position of the worktable. If it is in the printing position, the printing process is started directly. Otherwise, the worktable is moved to the printing position via PLC control. During the movement, the control system monitors the height of the worktable in real time to ensure that the height of the worktable is at the printing height. When the worktable moves to the printing position, the printing process is started.

[0021] Beneficial effects

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] By combining etching processes with a vision positioning platform, RIP printing driver, UV inkjet technology, PLC process control, and multi-threaded control technology, direct spraying of liquid photoresist on irregularly shaped areas to be etched on 40nm chips was achieved. This eliminates the need for photomask processing and allows the photoresist to be directly sprayed onto the points that need protection. This effectively improves key chip etching processes, increases chip manufacturing efficiency, and reduces chip manufacturing costs. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the workflow of a fully automated coating process for irregularly shaped areas on a silicon wafer surface according to the present invention.

[0025] Figure 2 This is an explanatory diagram for step one;

[0026] Figure 3 This is an explanatory diagram for step two.

[0027] Figure Labels

[0028] Workbench 1, jig 2, Mark point 3, silicon wafer 4, coating area 5, irregular area outline position 6, jig to be processed 7. Detailed Implementation

[0029] To better illustrate the content of this invention, the following description is provided in conjunction with the accompanying drawings and examples:

[0030] have Figures 1-3 As shown, this invention discloses a fully automated coating process for irregularly shaped areas on a silicon wafer surface, comprising the following specific steps:

[0031] Step one: First, select a silicon wafer 4 whose surface has been coated and fix it above the fixture 2, wherein the fixture 2 is as follows: Figure 2 The diagram shows a rectangle, with circular Mark points 3 marked at each of the four right-angled regions; as shown... Figure 2 As shown, the fixture 2 with silicon wafer 4 fixed is placed on the worktable 1. The control system acquires the image of the fixture 2 with silicon wafer 4 fixed in real time, selects the Mark point 3 area of ​​the fixture 2 diagonally, identifies the Mark point 3 image, obtains the center position of the Mark point 3 image, and saves the Mark point 3 image. According to the image of the coating area 5 presented by the computer, points are plotted along the coating area 5, and the outline of the coating area 5 is constructed using NURBS curves. The positions of each plotted point are manually adjusted to achieve accurate fitting of the outline of the coating area 5. The relative positional relationship between the center of Mark point 3 and each point of the outline of the coating area 5 is established, and the template is completed.

[0032] Step two, place the jig 7, with the uncoated silicon wafer 4 fixed on it, onto the worktable 1, as follows: Figure 3As shown, the control system acquires the image of the fixture 7 with the silicon wafer 4 fixed in real time, retrieves the established Mark point 3 template image, identifies the position of Mark point 3 diagonally, compares it with the position of the template Mark point 3 in step one, calculates the position deviation, and adjusts the outline of the coating area 5 obtained in step one according to the position deviation to obtain the outline position 6 of the irregular area on the surface of the current silicon wafer 4.

[0033] Step 3: Based on the size of the workbench 1, set the corresponding area in the computer memory. Using the GDI drawing method, set the image background and precision. Based on the irregular area outline position data 6 obtained in Step 2, draw the corresponding outline in memory, set the pen color, fill the area enclosed by the corresponding outline, and save it as a BMP format file to generate the print image.

[0034] Step four: Perform color separation and binarization on the BMP image file generated in step three, and use the ESC printing command to generate a printer instruction file;

[0035] Step 5: Using the USB communication transmission protocol, the generated printer instruction file is sent to the printer to realize the printing data transmission;

[0036] Step 6: The control system detects the position of worktable 1. If it is in the printing position, the printing process is started directly; otherwise, the PLC controls worktable 1 to move to the printing position. During the movement, the control system detects the height of worktable 1 in real time to ensure that the height of worktable 1 is at the printing height. When worktable 1 moves to the printing position, the printing process is started.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions created by the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fully automated coating process for irregularly shaped areas on a silicon wafer surface, comprising the following steps: Step 1: Template creation; Step two, location identification; Step 3: Generate the image; Step 4: Coating data generation; Step 5, data transmission; Step six, coating process control; The template creation mentioned in step one: ① First, select a silicon wafer (4) whose surface has been coated and fix it above the fixture (2). The fixture (2) is rectangular in shape, and circular Mark points (3) are set in the four right-angled areas of the fixture (2). ② Place the fixture (2) with the silicon wafer (4) fixed on the workbench (1), and control the system to capture images of the fixture (2) with the silicon wafer (4) fixed in real time. Select the Mark point (3) area of ​​the fixture (2) diagonally, identify the Mark point (3) image, obtain the center position of the Mark point (3) image, and save the Mark point (3) image. ③ Based on the image of the coated area (5) presented by the computer, plot points along the coated area (5), construct the outline of the coated area (5) using NURBS curves, manually adjust the position of each plotting point to achieve accurate fitting of the outline of the coated area (5), establish the relative positional relationship between the center of Mark point (3) and each point of the outline of the coated area (5), and complete the template establishment. The position identification in step two: the fixture (7) with the uncoated silicon wafer (4) fixed on it is placed on the worktable (1). The control system captures the image of the fixture (7) with the silicon wafer (4) fixed on it in real time, retrieves the template image of the Mark point (3), identifies the position of the Mark point (3) diagonally, compares it with the position of the Mark point (3) of the template in step one, calculates the position deviation, and adjusts the outline of the coating area (5) obtained in step one according to the position deviation to obtain the outline position (6) of the irregular area on the surface of the current silicon wafer (4). The image generation in step three is as follows: Based on the size of the workbench (1), set the corresponding size area in the computer memory, use the GDI drawing method to set the image background and precision, draw the corresponding outline in memory according to the irregular area outline position (6) obtained in step two, set the pen color, fill the area surrounded by the corresponding outline, and save it as a BMP format file to realize the generation of the print image; Step four involves generating coating data: the BMP image file generated in step three is color-separated and binarized, and the ESC printing command is used to generate a printer instruction file.

2. The fully automated coating process for irregularly shaped areas on a silicon wafer surface according to claim 1, characterized in that: The data transmission in step five involves using the USB communication transmission protocol to send the generated printer instruction file to the printer, thereby realizing the data transmission for printing.

3. The fully automated coating process for irregularly shaped areas on a silicon wafer surface according to claim 2, characterized in that: The coating process control in step six: The control system detects the position of the workbench (1). If it is in the printing position, the printing process is started directly; if it is not in the printing position, the workbench (1) is moved to the printing position by the PLC. During the movement, the control system detects the height of the workbench (1) in real time to ensure that the height of the workbench (1) is at the printing height. When the workbench (1) moves to the printing position, the printing process is started.

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