Method for reducing dry etching rejection rate

Abstract

The invention relates to the technical field of mask manufacturing, in particular to a method for reducing the rejection rate of dry etching, which can remarkably improve the stability and accuracy of dry etching by adopting high-quality etching equipment and instruments, accurately adjusting etching parameters and combining real-time monitoring and parameter adjustment, thereby improving the etching quality and simultaneously reducing the rejection rate of dry etching. The mask plate is subjected to shower dust removal treatment before entering the process cavity, and the shower parameters are adjusted according to the specification of the mask plate, so that particle dust is effectively removed, the defect risk is reduced, and the etching quality is further guaranteed. The measures further enable the whole production process to be more controllable and stable, the production efficiency is optimized, the rejection rate is reduced, and higher economic benefits are brought to enterprises.

Description

Technical Field

[0001] The invention relates to the technical field of mask manufacturing, and in particular to a method for reducing the scrap rate of dry etching. Background Art

[0002] At present, the 40nm photomask manufacturing industry occupies a vital position in semiconductor production. However, as the pattern lines of the photomask continue to be refined, the impact of particle dust on the yield of mask manufacturing products has become more and more significant. In particular, larger particle dust can directly cause the mask to be scrapped, causing great losses in the production process.

[0003] In the prior art, the dry etching process is usually as follows: the machine directly takes the mask off the stage and then places it in the process chamber for etching. During this process, the machine does not take into account the possible dust particles on the mask. Therefore, when dust particles exist, defects will be generated during the etching process, and eventually the mask will be scrapped. In a clean room environment, although the number of particles per unit space is strictly controlled, dust particles may still gather in specific areas, such as near the stage. When the stage is rising, the interlayer air flow rate will increase, forming a low-pressure area. This low-pressure area will attract the air in the clean room to be sucked into the stage. Unfortunately, dust particles are also brought in during this process, and eventually the dust particles will fall on the mask. The presence of these dust particles will seriously interfere with the subsequent dry etching process, resulting in etching defects, thereby making the mask scrapped.

[0004] Furthermore, we disclose a method for reducing the scrap rate of dry etching to meet the practical demand that particles and dust in the prior art are easily attached to the mask plate to interfere with the subsequent dry etching process and cause etching defects. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a method for reducing the scrap rate of dry etching, so as to solve the problem in the prior art that dust particles are easily attached to the mask and interfere with the subsequent dry etching process to cause etching defects.

[0006] Based on the above purpose, the present invention provides a method for reducing the scrap rate of dry etching, comprising: S1: Use high-quality etching equipment and instruments and determine appropriate etching parameters and thresholds. Adjust different parameters and thresholds according to specific conditions during the etching process. These parameters include pressure, plate temperature, RF matching, RF voltage, etc. S2: After the machine takes the mask out from the stage, it first needs to enter the shower dust removal equipment, where it is showered to remove the dust particles on the mask surface, reducing the risk of defects caused by the dust particles entering the process chamber. During the shower treatment, the intensity, time, angle and other parameters of the shower need to be changed according to the specific specifications of the mask to ensure that the dust particles can be effectively removed without causing damage to the mask. S3: After the showering work is completed, it is moved to the process chamber for etching in a clean room environment. During the etching process, special instruments and software are used to monitor and analyze the key parameters determined previously in real time to ensure the accuracy and real-time nature of the data. According to the real-time monitoring data, the parameters in the etching process are adjusted in time to keep them within the predetermined range.

[0007] Preferably, the air shower dust removal equipment includes a workbench and an air shower box, and the air shower box is fixedly connected to the middle part of the upper end surface of the workbench.

[0008] Preferably, an air pump is provided on one side of the middle part of the upper end of the shower box, the output end of the air pump is fixedly connected to an output pipe, the inner top of the shower box is fixedly connected to a diversion pipe, the lower end of the diversion pipe is fixedly connected to a plurality of nozzles at even intervals, the plurality of nozzles are all connected to the diversion pipe, the lower end of the output pipe extends into the interior of the shower box and is fixedly connected to the diversion pipe, and a pressure reducing valve is provided in the middle of the output pipe.

[0009] Preferably, both ends of the shower box are slidably connected with lifting doors, two sealing strips are provided at both ends of the shower box, a visual window is provided in the middle of the two lifting doors, and a tooth groove is provided on one side of the two lifting doors. A first motor is provided on the side of the upper end of the shower box away from the air pump, and the output end of the first motor is transmission-connected with a rotating rod, and the rotating rod is arranged at the upper end of the shower box through bearing seats on both sides, and both ends of the rotating rod are fixedly connected with a driving gear, and the driving gear is meshingly connected with the tooth groove on the lifting door.

[0010] Preferably, a rectangular groove is opened in the middle of the workbench, and a screw rod is rotatably connected inside the rectangular groove. A second motor is arranged in the middle of one end surface of the workbench, and the output end of the second motor extends into the interior of the rectangular groove and is fixedly connected to the screw rod. The external transmission of the screw rod is connected with a transmission block, and the transmission block is in an "I" shape.

[0011] Preferably, retractable sleeves are fixedly connected to both sides of the transmission block, one end of the two retractable sleeves is fixedly connected to the inner wall of the rectangular groove, the retractable sleeves are made of rubber material, and the retractable sleeves are arranged on the outside of the screw rod.

[0012] Preferably, the upper end of the transmission block is fixedly connected to an electric lifting platform, the upper end of the electric lifting platform is fixedly connected to a fixed seat, the upper end of the electric mechanical clamp is rotatably connected to the electric mechanical clamp, a third motor is provided on one side of the upper end of the fixed seat, the output end of the third motor extends into the interior of the fixed seat and is fixedly connected to the electric mechanical clamp.

[0013] Preferably, the inner wall of the upper jaw of the electric mechanical clamp is provided with anti-slip teeth.

[0014] Preferably, a plurality of through holes are provided on both sides of the middle portion of the upper end of the workbench.

[0015] Preferably, electric heating tubes are provided at the upper ends of both sides of the inner wall of the shower box.

[0016] Beneficial effects of the present invention: 1. The method for reducing the scrap rate of dry etching can significantly improve the stability and accuracy of dry etching by adopting high-quality etching equipment and instruments, and accurately adjusting the etching parameters, combined with real-time monitoring and parameter adjustment, thereby improving the etching quality. At the same time, the mask is subjected to a shower dust removal treatment before entering the process chamber, and the shower parameters are adjusted according to the mask specifications to effectively remove particle dust and reduce the risk of defects, thereby further ensuring the etching quality. These measures also make the entire production process more controllable and stable, optimize production efficiency, reduce the scrap rate, and bring higher economic benefits to the enterprise.

[0017] 2. The blowing and showering equipment in the method of reducing the scrap rate of dry etching ensures moderate blowing and showering force through an air pump and a pressure reducing valve, which can effectively remove the dust particles on the surface of the mask and avoid damage to the mask. In particular, the equipment realizes the rotation of the electric mechanical clamp through the drive of the third motor, so that the mask on the clamp can be blown and showered in multiple directions. This design greatly improves the uniformity and comprehensiveness of the blowing and showering, ensuring that all parts of the mask can be thoroughly cleaned. In addition, the adjustable height design of the electric lifting platform and the horizontal movement function of the screw drive system further enhance the flexibility of the equipment, enabling it to adapt to masks of different sizes and adjust the position of the mask as needed during the blowing and showering process. At the same time, the rapid drying function of the electric heating tube and the dust exhaust design of the through hole of the workbench further enhance the effect of blowing and showering dust removal and maintain the cleanliness of the working environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 This is a schematic diagram of the internal three-dimensional structure of the shower box of the present invention; Figure 3 for Figure 2 The enlarged view of point A in the middle; Figure 4 for Figure 2 The enlarged view of point B in the middle; Figure 5 It is a schematic diagram of the three-dimensional structure of the shunt pipe of the present invention; Figure 6 It is a schematic diagram of the three-dimensional structure of the electric mechanical gripper of the present invention.

[0020] The markings in the figure are: 1. Workbench; 2. Shower box; 3. Lifting door; 4. Air pump; 5. Pressure reducing valve; 6. First motor; 7. Rotating rod; 8. Driving gear; 9. Tooth groove; 10. Second motor; 11. Rectangular groove; 12. Electric lifting platform; 13. Electric mechanical gripper; 14. Transmission block; 15. Screw rod; 16. Retractable sleeve; 17. Visual window; 18. Sealing strip; 19. Output pipe; 20. Through hole; 21. Diverter pipe; 22. Nozzle; 23. Fixed seat; 24. Third motor; 25. Anti-skid teeth; 26. Electric heating tube. DETAILED DESCRIPTION

[0021] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0022] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words 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. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0023] like Figures 1 to 5 As shown, a method for reducing the scrap rate of dry etching comprises: S1: Use high-quality etching equipment and instruments and determine appropriate etching parameters and thresholds. Adjust different parameters and thresholds according to specific conditions during the etching process. These parameters include pressure, plate temperature, RF matching, RF voltage, etc. S2: After the machine takes the mask out from the stage, it first needs to enter the shower dust removal equipment, where it is showered to remove the dust particles on the mask surface, reducing the risk of defects caused by the dust particles entering the process chamber. During the shower treatment, the intensity, time, angle and other parameters of the shower need to be changed according to the specific specifications of the mask to ensure that the dust particles can be effectively removed without causing damage to the mask. S3: After the showering work is completed, it is moved to the process chamber for etching in a clean room environment. During the etching process, special instruments and software are used to monitor and analyze the key parameters determined previously in real time to ensure the accuracy and real-time nature of the data. According to the real-time monitoring data, the parameters in the etching process are adjusted in time to keep them within the predetermined range.

[0024] This method can significantly improve the stability and accuracy of dry etching by using high-quality etching equipment and instruments, and accurately adjusting etching parameters, combined with real-time monitoring and parameter adjustment, thereby improving etching quality. At the same time, the mask is blown and dusted before entering the process chamber, and the blowing parameters are adjusted according to the mask specifications to effectively remove particle dust and reduce the risk of defects, further ensuring etching quality. These measures also make the entire production process more controllable and stable, optimize production efficiency, reduce scrap rate, and bring higher economic benefits to the company.

[0025] Further, such as Figures 1 to 5As shown, the air shower dust removal equipment includes a workbench 1 and an air shower box 2, the air shower box 2 is fixedly connected to the middle of the upper end surface of the workbench 1, an air pump 4 is arranged on one side of the middle of the upper end of the air shower box 2, the output end of the air pump 4 is fixedly connected to an output pipe 19, the inner top of the air shower box 2 is fixedly connected to a shunt pipe 21, the lower end of the shunt pipe 21 is evenly spaced and fixedly connected to a plurality of nozzles 22, the plurality of nozzles 22 are all connected to the shunt pipe 21, the lower end of the output pipe 19 extends into the interior of the air shower box 2 and is fixedly connected to the shunt pipe 21, a pressure reducing valve 5 is arranged in the middle of the output pipe 19, and the air shower box 2 are slidably connected with lifting doors 3 at both ends, two sealing strips 18 are provided at both ends of the shower box 2, and visual windows 17 are provided in the middle of the two lifting doors 3. A tooth groove 9 is provided on one side of the two lifting doors 3. A first motor 6 is provided on the side of the upper end of the shower box 2 away from the air pump 4. The output end of the first motor 6 is connected with a rotating rod 7 in a transmission manner. The rotating rod 7 is arranged at the upper end of the shower box 2 through bearing seats on both sides. Both ends of the rotating rod 7 are fixedly connected with a driving gear 8, and the driving gear 8 is meshed with the tooth groove 9 on the lifting door 3. A rectangular groove 1 is provided in the middle of the workbench 1 1, the inner part of the rectangular groove 11 is rotatably connected with a screw rod 15, a second motor 10 is arranged in the middle of one end surface of the workbench 1, the output end of the second motor 10 extends into the inner part of the rectangular groove 11 and is fixedly connected with the screw rod 15, the outer transmission of the screw rod 15 is connected with a transmission block 14, the transmission block 14 is in an "I" shape, both sides of the transmission block 14 are fixedly connected with a retractable sleeve 16, one end of the two retractable sleeves 16 are fixedly connected with the inner side wall of the rectangular groove 11, the retractable sleeve 16 is made of rubber material, the retractable sleeve 16 is sleeved on the outside of the screw rod 15, the transmission block 14 The upper end of the workbench 1 is fixedly connected with an electric lifting platform 12, the upper end of the electric lifting platform 12 is fixedly connected with a fixing seat 23, the upper end of the electric mechanical clamp 13 is rotatably connected with the electric mechanical clamp 13, a third motor 24 is arranged on one side of the upper end of the fixing seat 23, the output end of the third motor 24 extends into the interior of the fixing seat 23 and is fixedly connected with the electric mechanical clamp 13, the inner wall of the upper clamp of the electric mechanical clamp 13 is provided with anti-slip teeth 25, a plurality of through holes 20 are opened on both sides of the middle part of the upper end of the workbench 1, and electric heating pipes 26 are arranged on the upper ends of both sides of the inner wall of the shower box 2; When the shower dust removal equipment is started, the air pump 4 starts to work, and the compressed air is delivered to the shunt pipe 21 through the output pipe 19, and then evenly distributed to each nozzle 22 by the shunt pipe 21, so as to realize comprehensive showering of the inside of the shower box 2. During the showering process, the pressure reducing valve 5 is used to adjust the air pressure to ensure that the showering force is moderate, which can effectively remove the particle dust on the surface of the mask without causing damage to the mask. At the same time, the first motor 6 drives the rotating rod 7 to rotate, and the driving gears 8 at both ends of the rotating rod 7 are engaged with the tooth grooves 9 on the lifting door 3, driving the lifting door 3 to automatically open or close, so as to facilitate the placement and removal of the mask. When the mask is placed on the electric mechanical clamp 13 on the electric lifting platform 12, the second motor 10 is started, driving the screw rod 15 to rotate, so that the transmission block 14 moves horizontally on the screw rod 15, and the mask is moved to the inside of the shower box 2, and the mask is blown and dusted. The third motor 24 is started to drive the motor The mechanical clamping claw 13 rotates, thereby realizing the blowing work of different directions of the mask on the clamping claw, ensuring that the blowing effect is more comprehensive. The electric lifting platform 12 can adjust the height as needed to adapt to masks of different sizes. During the blowing process, the lead screw 15 in the rectangular groove 11 opened in the middle of the workbench 1 rotates under the drive of the second motor 10, and drives the electric lifting platform 12 and the fixing seat 23 to move in the horizontal direction through the transmission block 14, so as to adjust the position of the mask in the blowing box 2 to ensure that the blowing is more uniform. The setting of the retractable sleeve 16 ensures the stability of the transmission block 14 during the movement, while reducing friction and noise. In addition, the electric heating tubes 26 at the upper ends of both sides of the inner wall of the blowing box 2 emit heat to quickly dry the fine liquid that may remain on the mask, further improving the blowing and dust removal effect. The multiple through holes 20 at the upper end of the workbench 1 are used to discharge dust and exhaust gas generated during the blowing process to keep the working environment clean.

[0026] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0027] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for reducing the scrap rate of dry etching, characterized in that: include: S1: Use high-quality etching equipment and instruments and determine appropriate etching parameters and thresholds. Adjust different parameters and thresholds according to specific conditions during the etching process. These parameters include pressure, plate temperature, RF matching, RF voltage, etc. S2: After the machine takes the mask out from the stage, it first needs to enter the shower dust removal equipment, where it is showered to remove the dust particles on the mask surface, reducing the risk of defects caused by the dust particles entering the process chamber. During the shower treatment, the intensity, time, angle and other parameters of the shower need to be changed according to the specific specifications of the mask to ensure that the dust particles can be effectively removed without causing damage to the mask. S3: After the showering work is completed, it is moved to the process chamber for etching in a clean room environment. During the etching process, special instruments and software are used to monitor and analyze the key parameters determined previously in real time to ensure the accuracy and real-time nature of the data. According to the real-time monitoring data, the parameters in the etching process are adjusted in time to keep them within the predetermined range.

2. The method for reducing the scrap rate of dry etching according to claim 1, characterized in that: The shower dust removal equipment comprises a workbench (1) and a shower box (2), wherein the shower box (2) is fixedly connected to the middle part of the upper end surface of the workbench (1).

3. The method for reducing the scrap rate of dry etching according to claim 2, characterized in that: An air pump (4) is provided on one side of the middle part of the upper end of the shower box (2); an output end of the air pump (4) is fixedly connected to an output pipe (19); a shunt pipe (21) is fixedly connected to the inner top of the shower box (2); a plurality of nozzles (22) are fixedly connected to the lower end of the shunt pipe (21) at even intervals; the plurality of nozzles (22) are all connected to the shunt pipe (21); the lower end of the output pipe (19) extends into the interior of the shower box (2) and is fixedly connected to the shunt pipe (21); a pressure reducing valve (5) is provided in the middle of the output pipe (19).

4. The method for reducing the scrap rate of dry etching according to claim 3, characterized in that: Both ends of the shower box (2) are slidably connected to a lifting door (3), and two sealing strips (18) are provided at both ends of the shower box (2). A visual window (17) is provided in the middle of the two lifting doors (3), and one side of the two lifting doors (3) is provided with a tooth groove (9). A first motor (6) is provided at the upper end of the shower box (2) away from the air pump (4), and the output end of the first motor (6) is transmission-connected to a rotating rod (7). The rotating rod (7) is arranged at the upper end of the shower box (2) through bearing seats on both sides, and both ends of the rotating rod (7) are fixedly connected to a driving gear (8), and the driving gear (8) is meshingly connected with the tooth groove (9) on the lifting door (3).

5. The method for reducing the scrap rate of dry etching according to claim 4, characterized in that: A rectangular groove (11) is provided in the middle of the workbench (1), a screw rod (15) is rotatably connected inside the rectangular groove (11), a second motor (10) is provided in the middle of one end surface of the workbench (1), an output end of the second motor (10) extends into the inside of the rectangular groove (11) and is fixedly connected to the screw rod (15), an external transmission connection of the screw rod (15) is provided with a transmission block (14), and the transmission block (14) is in an "I" shape.

6. The method for reducing the scrap rate of dry etching according to claim 5, characterized in that: Both sides of the transmission block (14) are fixedly connected with retractable sleeves (16), one end of each of the two retractable sleeves (16) is fixedly connected to the inner wall of the rectangular groove (11), the retractable sleeves (16) are made of rubber material, and the retractable sleeves (16) are sleeved on the outside of the screw rod (15).

7. The method for reducing the scrap rate of dry etching according to claim 6, characterized in that: The upper end of the transmission block (14) is fixedly connected to the electric lifting platform (12), the upper end of the electric lifting platform (12) is fixedly connected to the fixing seat (23), the upper end of the electric mechanical clamp (13) is rotatably connected to the electric mechanical clamp (13), a third motor (24) is provided on one side of the upper end of the fixing seat (23), the output end of the third motor (24) extends into the interior of the fixing seat (23) and is fixedly connected to the electric mechanical clamp (13).

8. The method for reducing the scrap rate of dry etching according to claim 7, characterized in that: The inner wall of the upper clamping jaw of the electric mechanical clamping jaw (13) is provided with anti-slip teeth (25).

9. The method for reducing the scrap rate of dry etching according to claim 8, characterized in that: A plurality of through holes (20) are provided on both sides of the middle portion of the upper end of the workbench (1).

10. The method for reducing the scrap rate of dry etching according to claim 9, characterized in that: Electric heating pipes (26) are provided at the upper ends of both sides of the inner wall of the shower box (2).

Images