Developing method

Abstract

The invention provides a developing method, which belongs to the technical field of integrated circuit photoetching and comprises the following steps of: providing an exposed wafer; pre-wetting the glued surface of the wafer by using deionized water; uniformly spraying a developing solution with a set temperature on the gluing surface of the wafer until the photoresist in the corresponding area on the wafer is removed; and detecting whether the amount of the developing solution on the wafer is smaller than a preset value or not in real time, and if so, spraying the developing solution on the gluing surface of the wafer. By optimizing the developing process, the use amount of the developing solution can be reduced and the quantity of dangerous wastes generated by reaction can be reduced while the wafer is ensured to be fully developed, so that the purpose of reducing the cost of treating the dangerous wastes is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuit lithography, and in particular to a developing method. Background Art

[0002] Integrated circuit lithography is a key step in the semiconductor manufacturing process, which mainly includes processes such as coating, exposure, development and etching. Among them, development is to chemically treat the exposed photoresist on the wafer to remove the photoresist in the unexposed area or the exposed area to form a photoresist pattern that is the same as the mask pattern.

[0003] The main component of the developer is tetramethylammonium hydroxide. When the wafer passes through the yellow light developing station, the developer is evenly sprayed on the rotating wafer surface by the developer, prompting the developer to undergo an acid-base neutralization reaction with the photoresist in the corresponding area, thereby obtaining a product whose line width, appearance, etc. meet the process requirements.

[0004] Since the developer is a strong alkaline mixed solution, the solution produced after reacting with the photoresist is a hazardous waste. However, the current development process often requires the use of a large amount of developer to ensure sufficient development, which produces a lot of hazardous waste, making the treatment cost of hazardous waste high. Summary of the invention

[0005] Based on this, an object of the present invention is to provide a developing method, aiming to optimize the developing process and reduce the amount of developer used while ensuring that the wafer is fully developed.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] The present invention provides a developing method, comprising the following steps:

[0008] Providing a wafer after exposure;

[0009] Pre-wetting the adhesive-coated surface of the wafer using deionized water;

[0010] Spraying a developer at a set temperature evenly on the coated surface of the rotating wafer multiple times until the photoresist in the corresponding area on the wafer is removed;

[0011] Real-time detection of whether the amount of developer on the wafer is less than a preset value;

[0012] If yes, the developer is sprayed on the glue-coated surface of the wafer again.

[0013] Furthermore, the step of spraying the developer at a set temperature uniformly on the coating surface of the rotating wafer for multiple times until the photoresist in the corresponding area on the wafer is removed specifically includes:

[0014] Evenly spraying the developer on the adhesive-coated surface of the wafer within a first time period;

[0015] Evenly spraying the developer on the adhesive-coated surface of the wafer within a second time period;

[0016] The developer is evenly sprayed on the glue-coated surface of the wafer within a third time period.

[0017] Furthermore, the step of uniformly spraying the developer on the adhesive-coated surface of the wafer within the first time period specifically includes:

[0018] Spraying the developer on the adhesive coating surface of the wafer for a first sub-period at a preset flow rate, wherein the rotation speed of the wafer is 40 rad / min to 80 rad / min;

[0019] The rotation speed of the wafer is reduced to 8 rad / min to 12 rad / min and continued for a second sub-period;

[0020] Increasing the rotation speed of the wafer to 640 rad / min-960 rad / min and continuing for a third sub-period;

[0021] The second sub-time period is greater than the first sub-time period and the third sub-time period.

[0022] Furthermore, the step of uniformly spraying the developer on the adhesive-coated surface of the wafer within the second time period specifically includes:

[0023] Performing an operation of spraying the developer on the adhesive coating surface of the wafer for a fourth sub-time period at a preset flow rate, wherein a rotation speed of the wafer is 40 rad / min to 80 rad / min;

[0024] The rotation speed of the wafer is reduced to 8 rad / min to 12 rad / min and continued for a fifth sub-period;

[0025] Increasing the rotation speed of the wafer to 640 rad / min-960 rad / min and continuing for a sixth sub-period;

[0026] The fifth sub-time period is greater than the fourth sub-time period and the sixth sub-time period.

[0027] Furthermore, the step of uniformly spraying the developer on the adhesive-coated surface of the wafer within the third time period specifically includes:

[0028] Performing an operation of spraying the developer on the adhesive-coated surface of the wafer for a seventh sub-period at a preset flow rate, wherein a rotation speed of the wafer is 40 rad / min to 80 rad / min;

[0029] The rotation speed of the wafer is reduced to 8 rad / min to 12 rad / min and continued for an eighth sub-period;

[0030] The rotation speed of the wafer is reduced to 4 rad / min to 6 rad / min and continued for a ninth sub-period;

[0031] Increasing the rotation speed of the wafer to 8 rad / min to 12 rad / min and continuing for a tenth sub-period;

[0032] The eighth sub-time period, the ninth sub-time period and the tenth sub-time period are all greater than the seventh sub-time period.

[0033] Furthermore, uniform spraying and re-spraying are performed on the adhesive coating surface of the wafer at a flow rate of 400 mL / min to 450 mL / min for 3 seconds.

[0034] Furthermore, the second sub-time period is 20 seconds, and the third sub-time period is 5 seconds.

[0035] Further, the fifth sub-time period is 20 seconds, and the sixth sub-time period is 5 seconds.

[0036] Further, the eighth sub-time period is 20 seconds, the ninth sub-time period is 15 seconds, and the tenth sub-time period is 10 seconds.

[0037] Furthermore, the temperature of the developer is 19°C to 23°C.

[0038] The beneficial effects of the present invention include at least: pre-wetting the wafer with deionized water first, which helps to improve the adhesion performance of the subsequent developer on the wafer surface, improve the uniformity of the developer distribution, and enable the subsequent developer to better react with the photoresist. At the same time, when spraying the developer, strictly control the temperature of the developer, and by spraying the developer in small amounts and multiple times, the developer can be more evenly distributed on the photoresist surface, reducing the phenomenon of local uneven development and ensuring the consistency of the development effect. In addition, during the development process, by real-time detection of the amount of developer, it is ensured that the developer fully covers the coated surface of the wafer, thereby ensuring that there is enough developer to fully react with the photoresist in the exposure area or the non-exposure area. In this way, while ensuring that the developer fully reacts with the photoresist in the corresponding area, the overall use of the developer can be reduced, avoiding overspray and generating a large amount of hazardous waste, thereby reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a flow chart of a developing method in one embodiment of the present invention;

[0040] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0041] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0042] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0044] Based on the content in the background technology, in order to ensure that the photoresist on the wafer is fully developed, it is usually necessary to evenly spray a large amount of developer on the surface of the wafer so that the alkaline developer and the photoresist in the corresponding area can undergo sufficient acid-base neutralization reaction, which will produce a large amount of hazardous waste, and the treatment of hazardous waste will increase production costs.

[0045] Based on this, the present application provides a development method, which, by optimizing the development process, can reduce the amount of developer used while ensuring that the wafer is fully developed, thereby reducing the amount of hazardous waste generated by the reaction, thereby achieving the purpose of reducing the cost of treating hazardous waste.

[0046] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0047] Please refer to Figure 1 , is a flow chart of a developing method provided by an embodiment of the present invention, comprising steps S100 to S400:

[0048] Step S100: providing an exposed wafer. Specifically, during the exposure process of the wafer, the wafer is first fixed on a rotating stage, and then the pattern on the mask is projected onto a surface of the wafer coated with photoresist through a photolithography process. For example, ultraviolet light is used to irradiate positive photoresist, and the positive photoresist in the area irradiated by the ultraviolet light reacts chemically with a developer.

[0049] Step S200: pre-wetting the adhesive coating surface of the wafer using deionized water;

[0050] In this step, the wetting effect of deionized water can help the subsequent developer to react better with the photoresist, thereby improving the uniformity and effect of development;

[0051] Of course, in order to avoid too much deionized water affecting the full contact between the subsequent developer and the photoresist, the deionized water on the wafer surface needs to be evenly distributed and the excess deionized water needs to be removed. To this end, the wafer needs to be rotated at a low speed, and the deionized water is evenly distributed on the wafer surface through the centrifugal force generated by the rotation, and the excess deionized water on the wafer surface needs to be removed;

[0052] Preferably, the rotation speed of the wafer is adjusted to 1200rad / min~800rad / min, and the wafer is rotated for 2 seconds, then the rotation speed of the wafer is adjusted to 1600rad / min~2400rad / min, and deionized water is evenly sprayed on the glue-coated surface of the wafer at a flow rate of 330mL / min~400mL / min for 0.5s, and finally the rotation speed of the rotating stage is kept unchanged and the wafer is continued to rotate for 3 seconds, so that the pre-wetting effect of the deionized water reaches a better level.

[0053] Step S300: spraying a developer at a set temperature evenly on the coated surface of the rotating wafer for multiple times until the photoresist in the corresponding area on the wafer is removed. For positive photoresist, the sprayed developer reacts with the exposed area of ​​the photoresist, and for negative photoresist, the sprayed developer reacts with the unexposed area of ​​the photoresist;

[0054] At the same time, in order to avoid the influence of the temperature change of the developer on the development effect, the developer to be sprayed is temperature-controlled in this step so that the acid-base neutralization reaction between the developer and the photoresist proceeds at a uniform and stable speed. Optionally, the temperature of the developer to be sprayed can be detected and adjusted in real time by a temperature controller so that the temperature of the developer finally sprayed on the wafer is kept within a certain range;

[0055] In addition, in order to ensure that the developer is evenly spread on the adhesive coating surface of the wafer under the centrifugal force generated by the rotation of the wafer after spraying, the developer is sprayed just above the center of the wafer;

[0056] Preferably, the temperature of the developer is controlled at 19°C to 23°C.

[0057] Step S400: Real-time detection of whether the amount of developer on the wafer is less than a preset value, and if so, spraying developer of a set temperature onto the adhesive-coated surface of the wafer;

[0058] On the one hand, the developer after spraying will react with the exposed area or non-exposed area of ​​the photoresist and gradually decrease. On the other hand, under the action of the centrifugal force generated by the rotation of the wafer, part of the developer will be thrown out from the edge of the wafer and reduced. Therefore, this step determines whether the amount of developer that fully reacts with the photoresist is sufficient by real-time detection of whether the amount of developer on the wafer is less than the preset value, so as to ensure that the developer fully covers the coated surface of the wafer and ensures that the developer and the photoresist fully react.

[0059] Optionally, the weight of the wafer on the rotating stage can be obtained in real time through a weight sensor. The weight sensor is linked with the control unit to monitor the spraying process of the developer in step S300 in real time. When the weight of the developer on the wafer is less than the set value, it means that the developer needs to be re-sprayed. In this way, the re-spraying of the developer can prevent incomplete coverage of the developer and insufficient development.

[0060] In this embodiment, the wafer is first pre-wetted with deionized water, which helps to improve the adhesion performance of the subsequent developer on the wafer surface and improve the uniformity of the developer distribution, so that the subsequent developer can better react with the photoresist. At the same time, when spraying the developer, the temperature of the developer is strictly controlled to ensure the consistency of the development effect. In addition, during the development process, the amount of developer is detected in real time to ensure that the developer fully covers the coated surface of the wafer, thereby ensuring that there is enough developer to fully react with the photoresist. In this way, while ensuring that the developer fully reacts with the photoresist in the corresponding area, the amount of developer sprayed can be strictly controlled to avoid overspraying and generating a large amount of hazardous waste.

[0061] In some optional embodiments, step S300 specifically includes steps S310 to S330:

[0062] Step S310: spraying a developer at a set temperature uniformly on the adhesive coating surface of the wafer within a first time period;

[0063] Step S320: spraying the developer at a set temperature uniformly on the adhesive coating surface of the wafer within a second time period;

[0064] Step S330: spraying the developer at a set temperature uniformly on the adhesive coating surface of the wafer within a third time period;

[0065] In this embodiment, by spraying the developer in small amounts multiple times, the developer can be more evenly distributed on the photoresist surface, reducing the phenomenon of local uneven development. At the same time, while ensuring the development effect, the overall amount of developer used can be reduced to reduce costs. In addition, multiple spraying can make the development process more precise, which helps to improve the accuracy and resolution of development. In this way, while ensuring that the developer fully reacts with the photoresist in the corresponding area, the amount of developer used is reduced.

[0066] In some optional embodiments, step S310 specifically includes steps S311 to S313:

[0067] Step S311: spraying the developer on the adhesive coating surface of the wafer for a first sub-period of time at a preset flow rate, wherein the rotation speed of the wafer is 40 rad / min to 80 rad / min;

[0068] Step S312: reducing the rotation speed of the wafer to 8 rad / min-12 rad / min and continuing for a second sub-period;

[0069] Step S313: increasing the rotation speed of the wafer to 640 rad / min-960 rad / min and continuing for a third sub-period;

[0070] In step S310 , the second sub-time period is greater than the first sub-time period and the third sub-time period.

[0071] In this embodiment, the rotation speed of the wafer is controlled in time periods. When rotating at a low speed, the developer is spread evenly on the surface of the wafer, so that the developer and the photoresist are in full contact and reaction. When rotating at a high speed, the reactants of the developer and the photoresist are thrown out of the wafer, so that the surface of the wafer remains relatively clean, which is conducive to subsequent development and high-quality reaction.

[0072] In some optional embodiments, step S320 specifically includes steps S321 to S323:

[0073] Performing a fourth sub-period of spraying the developer on the adhesive-coated surface of the wafer at a preset flow rate, wherein the rotation speed of the wafer is 40 rad / min to 80 rad / min;

[0074] reducing the rotation speed of the wafer to 8 rad / min to 12 rad / min and continuing for a fifth sub-period;

[0075] The rotation speed of the wafer is increased to 640 rad / min to 960 rad / min and continued for a sixth sub-period;

[0076] In step S320 , the fifth sub-time period is greater than the fourth sub-time period and the sixth sub-time period.

[0077] In this embodiment, the rotation speed of the wafer is controlled in time periods. When rotating at a low speed, the developer is spread evenly on the surface of the wafer, so that the developer and the photoresist are in full contact and reaction. When rotating at a high speed, the reactants of the developer and the photoresist are thrown out of the wafer, so that the surface of the wafer remains relatively clean, which is conducive to subsequent development and high-quality reaction.

[0078] In some optional embodiments, step S330 specifically includes steps S331 to S334:

[0079] Step S331: spraying the developer on the adhesive coating surface of the wafer for a seventh sub-period at a preset flow rate, wherein the rotation speed of the wafer is 40 rad / min to 80 rad / min;

[0080] Step S332: reducing the rotation speed of the wafer to 8 rad / min-12 rad / min and continuing for the eighth sub-period;

[0081] Step S333: reducing the rotation speed of the wafer to 4 rad / min to 6 rad / min and continuing for a ninth sub-period;

[0082] Step S334: increasing the rotation speed of the wafer to 8 rad / min to 12 rad / min and continuing for the tenth sub-period;

[0083] In step S330 , the eighth sub-time period, the ninth sub-time period, and the tenth sub-time period are all greater than the seventh sub-time period.

[0084] In this embodiment, the rotation of the wafer is controlled at a low speed in time periods, so that the developer can be fully and evenly spread on the surface of the wafer, so that the developer and the photoresist can fully contact and react, thereby ensuring a better development effect.

[0085] Preferably, the glue-coated surface of the wafer is evenly sprayed for 3 seconds at a flow rate of 400mL / min to 450mL / min, and when it is detected that the amount of developer on the wafer is less than a preset value, the glue-coated surface of the wafer is also evenly sprayed for 3 seconds at a flow rate of 400mL / min to 450mL / min.

[0086] Preferably, the second sub-time period is 20 seconds, and the third sub-time period is 5 seconds.

[0087] Preferably, the fifth sub-time period is 20 seconds, and the sixth sub-time period is 10 seconds.

[0088] Preferably, the eighth sub-time period is 20 seconds, the ninth sub-time period is 15 seconds, and the tenth sub-time period is 10 seconds.

[0089] In some optional embodiments, the present invention provides a developing method, further comprising step S500:

[0090] Adjust the wafer rotation speed to 1200rad / min~1800rad / min, and spray the front and back surfaces of the wafer with deionized water at a preset flow rate for 10s. Then increase the wafer rotation speed to 1600rad / min~2400rad / min, and spray the front and back surfaces of the wafer with deionized water at a preset flow rate for 3s. Then increase the wafer rotation speed to 2800rad / min~3200rad / min, and spray the front and back surfaces of the wafer with deionized water at a preset flow rate for 10s. Then keep the wafer rotation speed unchanged and continue to rotate the wafer for 9s. Finally, adjust the wafer rotation speed to 1200rad / min~1800rad / min, and continue to rotate the wafer for 1s.

[0091] In this embodiment, the rotation of the wafer is controlled in time periods. First, the developer and the reactants of the developer and the photoresist on the wafer are thrown out from the edge of the wafer using the centrifugal force generated by the deionized water and the rotation of the wafer. Then, the deionized water used for rinsing is thrown out from the edge of the wafer using the centrifugal force generated by the rotation of the wafer, and finally a clean wafer is obtained.

[0092] The present invention will be further described below with specific embodiments:

[0093] Embodiment 1:

[0094] This embodiment provides a developing method, which includes steps S10 to S80:

[0095] Step S10: providing an exposed wafer and fixing the wafer on a rotating stage;

[0096] Step S20: adjusting the rotation speed of the rotating stage to 1200 rad / min-800 rad / min, and rotating the wafer for 2 seconds, then adjusting the rotation speed of the rotating stage to 1600 rad / min-2400 rad / min, and spraying deionized water evenly on the adhesive surface of the wafer at a flow rate of 330 mL / min-400 mL / min for 0.5 seconds, and finally keeping the rotation speed of the rotating stage unchanged, and rotating the wafer for another 3 seconds;

[0097] Step S30: adjusting the rotation speed of the rotating stage to 40 rad / min, and spraying a developer at 21° C. at a flow rate of 400 mL / min for 3 seconds on the wafer with a rotation speed of 40 rad / min, then adjusting the rotation speed of the rotating stage to 8 rad / min-12 rad / min, and continuing for 20 seconds, and then adjusting the rotation speed of the rotating stage to 640 rad / min-960 rad / min, and continuing for 5 seconds;

[0098] Step S40: adjusting the rotation speed of the rotating stage to 40 rad / min, and spraying a developer at 21° C. at a flow rate of 400 mL / min for 3 seconds on the wafer with a rotation speed of 40 rad / min, then adjusting the rotation speed of the rotating stage to 8 rad / min-12 rad / min, and continuing for 20 seconds, and then adjusting the rotation speed of the rotating stage to 640 rad / min-960 rad / min, and continuing for 10 seconds;

[0099] Step S50: adjusting the rotation speed of the rotating stage to 40 rad / min, and spraying a developer at 21° C. for 3 seconds at a flow rate of 400 mL / min on the wafer with a rotation speed of 40 rad / min, then adjusting the rotation speed of the rotating stage to 8 rad / min-12 rad / min, and continuing for 20 seconds, then adjusting the rotation speed of the rotating stage to 4 rad / min-6 rad / min, and continuing for 15 seconds, then adjusting the rotation speed of the rotating stage to 8 rad / min-12 rad / min, and continuing for 10 seconds;

[0100] Step S60: adjust the speed of the rotating stage to 1500rad / min, and spray the front and back surfaces of the wafer with a preset flow rate of deionized water for 10 seconds, then increase the speed of the rotating stage to 2000rad / min, and spray the front and back surfaces of the wafer with a preset flow rate of deionized water for 3 seconds, then increase the speed of the rotating stage to 3500rad / min, and spray the front and back surfaces of the wafer with a preset flow rate of deionized water for 10 seconds, then keep the speed of the rotating stage unchanged, and let the wafer continue to rotate for 9 seconds, and finally adjust the speed of the rotating stage to 1500rad / min, and let the wafer continue to rotate for 1 second.

[0101] Embodiment 2:

[0102] This embodiment provides a developing method. Different from the developing method provided in Embodiment 1, in this embodiment, in step S30, step S40 and step S50, the rotation speed of the rotating stage is adjusted to 40 rad / min, and the developer at 21°C is sprayed on the wafer with a rotation speed of 40 rad / min for 3 seconds at a flow rate of 425 mL / min.

[0103] Embodiment three:

[0104] This embodiment provides a developing method. Different from the developing method provided in Embodiment 1, in this embodiment, in step S30, step S40 and step S50, the rotation speed of the rotating stage is adjusted to 40 rad / min, and the developer at 21°C is sprayed on the wafer with a rotation speed of 40 rad / min for 3 seconds at a flow rate of 450 mL / min.

[0105] Embodiment 4:

[0106] This embodiment provides a developing method. Different from the developing method provided in Embodiment 1, in this embodiment, in step S30, step S40 and step S50, the rotation speed of the rotating stage is adjusted to 60 rad / min, and the developer at 21°C is sprayed on the wafer with a rotation speed of 60 rad / min for 3 seconds at a flow rate of 400 mL / min.

[0107] Embodiment five:

[0108] This embodiment provides a developing method. Different from the developing method provided in Embodiment 1, in this embodiment, in step S30, step S40 and step S50, the rotation speed of the rotating stage is adjusted to 60 rad / min, and the developer at 21°C is sprayed on the wafer with a rotation speed of 60 rad / min for 3 seconds at a flow rate of 425 mL / min.

[0109] Embodiment six:

[0110] This embodiment provides a developing method. Different from the developing method provided in Embodiment 1, in this embodiment, in step S30, step S40 and step S50, the rotation speed of the rotating stage is adjusted to 60 rad / min, and the developer at 21°C is sprayed on the wafer with a rotation speed of 60 rad / min for 3 seconds at a flow rate of 450 mL / min.

[0111] Embodiment seven:

[0112] This embodiment provides a developing method. Different from the developing method provided in Embodiment 1, in this embodiment, in step S30, step S40 and step S50, the rotation speed of the rotating stage is adjusted to 80 rad / min, and the developer at 21°C is sprayed on the wafer with a rotation speed of 80 rad / min for 3 seconds at a flow rate of 400 mL / min.

[0113] Embodiment eight:

[0114] This embodiment provides a developing method. Different from the developing method provided in Embodiment 1, in this embodiment, in step S30, step S40 and step S50, the rotation speed of the rotating stage is adjusted to 80 rad / min, and the developer at 21°C is sprayed on the wafer with a rotation speed of 80 rad / min for 3 seconds at a flow rate of 425 mL / min.

[0115] Embodiment nine:

[0116] This embodiment provides a developing method. Different from the developing method provided in Embodiment 1, in this embodiment, in step S30, step S40 and step S50, the rotation speed of the rotating stage is adjusted to 80 rad / min, and the developer at 21°C is sprayed on the wafer with a rotation speed of 80 rad / min for 3 seconds at a flow rate of 450 mL / min.

[0117] Comparative Example 1:

[0118] This embodiment provides a developing method. Different from the developing method provided in the first embodiment, in this embodiment, step S20 is not implemented.

[0119] Comparative Example 2:

[0120] This embodiment provides a developing method. Different from the developing method provided in the first embodiment, in this embodiment, step S20 is not implemented, and the developer to be sprayed is not subjected to a heat preservation treatment.

[0121] Comparative Example 3:

[0122] This embodiment provides a developing method. Different from the developing method provided in the first embodiment, in this embodiment, the developer to be sprayed is not subjected to a heat preservation treatment.

[0123] The developing methods provided in Examples 1 to 9 and Comparative Examples 1 to 3 are used to calculate the minimum amount (ml) of developer required for each example while ensuring sufficient development of the wafer. The specific data are shown in Table 1:

[0124] Table 1

[0125]

[0126]

[0127] As can be seen from Table 1, compared with the case where deionized water is not used to pre-wet the wafer in Comparative Example 1, the minimum amount of developer required in the development method provided by Examples 1 to 9 of the present invention is greatly reduced, and compared with the case where deionized water is not used to pre-wet the wafer and the developer to be sprayed is not subjected to heat preservation treatment in Comparative Example 2, the minimum amount of developer required in the development method provided by Examples 1 to 9 of the present invention is reduced by a greater margin, and compared with the case where the developer to be sprayed is not subjected to heat preservation treatment in Comparative Example 3, the minimum amount of developer required in the development method provided by Examples 1 to 9 of the present invention is also greatly reduced. This shows that by pre-wetting the wafer with deionized water and strictly controlling the temperature of the developer when spraying the developer, the overall amount of developer used can be significantly reduced while ensuring that the developer fully reacts with the photoresist in the corresponding area.

[0128] In summary, the present application first pre-wets the wafer with deionized water, which helps to improve the adhesion performance of the subsequent developer on the wafer surface, improve the uniformity of the developer distribution, and enable the subsequent developer to better react with the photoresist. At the same time, when spraying the developer, strictly control the temperature of the developer, and by spraying the developer in small amounts and multiple times, the developer can be more evenly distributed on the photoresist surface, reducing the phenomenon of local uneven development and ensuring the consistency of the development effect. In addition, during the development process, by real-time detection of the amount of developer, it is ensured that the developer fully covers the coated surface of the wafer, thereby ensuring that there is enough developer to fully react with the photoresist exposure area or non-exposure area. In this way, while ensuring that the developer fully reacts with the photoresist in the corresponding area, the overall use of the developer can be reduced, avoiding overspray and generating a large amount of hazardous waste, and reducing costs.

[0129] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0130] The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the protection scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A developing method, characterized in that: The developing method comprises: Providing a wafer after exposure; Pre-wetting the adhesive-coated surface of the wafer using deionized water; Spraying a developer at a set temperature evenly on the coated surface of the rotating wafer multiple times until the photoresist in the corresponding area on the wafer is removed; Real-time detection of whether the amount of developer on the wafer is less than a preset value; If yes, the developer is sprayed on the glue-coated surface of the wafer again.

2. The developing method according to claim 1, characterized in that: The step of spraying the developer at a set temperature uniformly on the coated surface of the wafer for multiple times until the photoresist in the corresponding area on the wafer is removed specifically includes: Evenly spraying the developer on the adhesive-coated surface of the wafer within a first time period; Evenly spraying the developer on the adhesive-coated surface of the wafer within a second time period; The developer is evenly sprayed on the glue-coated surface of the wafer within a third time period.

3. The developing method according to claim 2, characterized in that: The step of uniformly spraying the developer on the adhesive-coated surface of the wafer within the first time period specifically includes: Spraying the developer on the adhesive coating surface of the wafer for a first sub-period at a preset flow rate, wherein the rotation speed of the wafer is 40 rad / min to 80 rad / min; The rotation speed of the wafer is reduced to 8 rad / min to 12 rad / min and continued for a second sub-period; Increasing the rotation speed of the wafer to 640 rad / min-960 rad / min and continuing for a third sub-period; The second sub-time period is greater than the first sub-time period and the third sub-time period.

4. The developing method according to claim 3, characterized in that: The step of uniformly spraying the developer on the adhesive-coated surface of the wafer within the second time period specifically includes: Performing an operation of spraying the developer on the adhesive coating surface of the wafer for a fourth sub-time period at a preset flow rate, wherein a rotation speed of the wafer is 40 rad / min to 80 rad / min; The rotation speed of the wafer is reduced to 8 rad / min to 12 rad / min and continued for a fifth sub-period; Increasing the rotation speed of the wafer to 640 rad / min-960 rad / min and continuing for a sixth sub-period; The fifth sub-time period is greater than the fourth sub-time period and the sixth sub-time period.

5. The developing method according to claim 4, characterized in that: The step of uniformly spraying the developer on the adhesive-coated surface of the wafer within the third time period specifically includes: Performing an operation of spraying the developer on the adhesive-coated surface of the wafer for a seventh sub-period at a preset flow rate, wherein a rotation speed of the wafer is 40 rad / min to 80 rad / min; The rotation speed of the wafer is reduced to 8 rad / min to 12 rad / min and continued for an eighth sub-period; The rotation speed of the wafer is reduced to 4 rad / min to 6 rad / min and continued for a ninth sub-period; Increasing the rotation speed of the wafer to 8 rad / min to 12 rad / min and continuing for a tenth sub-period; The eighth sub-time period, the ninth sub-time period and the tenth sub-time period are all greater than the seventh sub-time period.

6. The developing method according to any one of claims 3 to 5, characterized in that: The adhesive coating surface of the wafer is evenly sprayed and re-sprayed for 3 seconds at a flow rate of 400 ml / min to 450 ml / min.

7. The developing method according to claim 6, characterized in that: The second sub-time period is 20 seconds, and the third sub-time period is 5 seconds.

8. The developing method according to claim 7, characterized in that: The fifth sub-time period is 20 seconds, and the sixth sub-time period is 5 seconds.

9. The developing method according to claim 8, characterized in that: The eighth sub-time period is 20 seconds, the ninth sub-time period is 15 seconds, and the tenth sub-time period is 10 seconds.

10. The developing method according to claim 1, characterized in that: The temperature of the developer is 19°C to 23°C.

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