Wafer cleaning method and wafer cleaning device

Abstract

This application discloses a wafer cleaning method and apparatus for cleaning the surface of a polished wafer. The wafer cleaning method includes the steps of: (1) wetting the wafer surface with DIW (deionized water); (2) spraying SC1 (scrubbing solution) at a first set temperature onto the wafer surface; (3) controlling a brush to scrub the wafer surface while continuing to spray SC1 (scrubbing solution) at the first set temperature onto the wafer surface; (4) spray-cleaning the scrubbed wafer surface with DIW at a second set temperature for a first set time; (5) repeating steps S103 through S104 a first set number of times; and (6) alternately cleaning the wafer surface with DHF and DIO3 after performing step S105. This allows for a transition step of spray-cleaning with DIW at a second set temperature during multiple consecutive scrubs. Residual materials on the wafer surface can be sufficiently removed with a single scrub, effectively improving the cleaning effect of the polished wafer.

Description

[Technical Field]

[0001] The present application relates to the field of semiconductor cleaning, and more particularly to a wafer cleaning method and wafer cleaning apparatus for cleaning the surface of a polished wafer. [Background technology]

[0002] Single-sided polishing of wafers is one of the main polishing methods in wafer manufacturing. Single-sided polishing has the advantages of high flatness and mature technology. The process mainly involves wax application, attachment, polishing, pre-cleaning, and de-attachment. However, after a wafer is polished, a large amount of polishing fluid containing micron- and nano-sized particles remains on the wafer's front surface, and the resin wax required for attachment remains on the wafer's back surface, making cleaning difficult. Therefore, cleaning the polished wafer's front surface has a significant impact on product yield and is a critical process in wafer manufacturing.

[0003] Currently, two main methods are used to clean the surfaces of polished wafers: multi-tank immersion chemical wet cleaning and single-wafer contact cleaning. Multi-tank immersion chemical wet cleaning involves sequentially immersing wafers in tanks containing DIO3 (dissolved ozone in deionized water), DHF (dilute hydrofluoric acid), SC1 (ammonia, hydrogen peroxide, and water mixture), DIW (deionized water), and other chemicals to remove particles, contaminants, and native oxide layers from the wafer surface. This method has the advantage of being mature and highly productive. Single-wafer contact cleaning first removes particles from the wafer surface using a friction process between a brush and wafer in a single scrubbing chamber, combined with the reaction of cleaning agents such as SC1. The wafer then enters a single cleaning chamber, where the surface oxide layer is stripped using DIO3 and DHF to remove metal residues. Compared to multi-tank immersion cleaning, single-wafer contact cleaning effectively increases the efficiency of single cleaning and avoids inter-wafer contamination. It is also suitable for multiple wafers of different thicknesses.

[0004] Research has shown that multi-tank immersion chemical wet cleaning is a relatively simple process. However, this process not only requires a long cleaning time and can lead to contamination between wafers, but also fails to effectively remove the wax remaining on the backside of the wafer after single-sided polishing. The oxide layer on the backside of the wafer is covered with the remaining wax, resulting in uneven etching. However, single-wafer contact cleaning has high particle requirements, requiring the wafer to be kept wet. After the particles dry, they strongly adsorb physically and chemically to the wafer surface. This makes it difficult for the cleaning effect of the conventional process to meet manufacturing requirements.

[0005] Considering the problem that the cleaning effect of the single wafer contact cleaning in the prior art is difficult to meet production requirements, no effective solution has been proposed at present. Summary of the Invention

[0006] The embodiments of the present application provide a method for cleaning the surface of a polished wafer, solving the problem in the prior art that the cleaning effect of the wafer in single-wafer contact cleaning is difficult to meet the manufacturing requirements.

[0007] In a first aspect, according to an embodiment of the present application, there is provided a wafer cleaning method for cleaning a surface of a polished wafer, the method comprising: Step S101: Wetting the surface of the wafer with DIW; Step S102: spraying SC1 having a first set temperature onto the surface of the wafer; Step S103: continuously spraying the SC1 having the first set temperature onto the surface of the wafer while simultaneously controlling the brush to scrub the surface of the wafer; Step S104: spray cleaning the scrubbed wafer surface with DIW at a second set temperature for a first set time; Step S105: repeating steps S103 and S104 a first set number of times; and After step S105 is performed, step S106 is provided in which the surface of the wafer is alternately cleaned with DHF and DIO3.

[0008] In a second aspect, according to an embodiment of the present application, there is provided another method for cleaning a wafer, the method comprising: Step S201: Wetting the surface of the wafer with DIW; Step S202: spraying SC1 having a first set temperature onto the surface of the wafer; Step S203: continuously spraying the SC1 having the first set temperature onto the surface of the wafer while simultaneously controlling the brush to scrub the surface of the wafer; Step S204, after scrubbing, performs megasonic cleaning on the surface of the wafer at a set power; Step S205: repeating steps S203 and S204 up to a second set number of times; and After step S205 is performed, step S206 is provided in which the surface of the wafer is alternately cleaned with DHF and DIO3.

[0009] In a third aspect, according to an embodiment of the present application, there is provided another method for cleaning a wafer, the method comprising: Step S301: Wetting the surface of the wafer with DIW; Step S302: spraying SC1 having a first set temperature onto the surface of the wafer; Step S303: Continue spraying SC1 having a first set temperature onto the surface of the wafer, while simultaneously controlling the brush to scrub the surface of the wafer, and perform megasonic cleaning at a set power until a second set time; and After step S303 is performed, step S304 is provided in which the surface of the wafer is alternately cleaned with DHF and DIO3.

[0010] In a fourth aspect, according to an embodiment of the present application, there is provided another method for cleaning a wafer, the method comprising: Step S401: Wetting the surface of the wafer with DIW; Step S402: spraying SC1 having a first set temperature onto the surface of the wafer; Step S403: continuously spraying SC1 having a first set temperature onto the surface of the wafer, and simultaneously controlling the brush to scrub the surface of the wafer for a third set time, and performing megasonic cleaning with a set power; Step S404: spraying SC1 having a first set temperature onto the surface of the wafer, controlling the brush to stop scrubbing the surface of the wafer, and stopping the megasonic cleaning at the set power until a fourth set time; Step S405: repeating steps S403 and S404 up to a third set number of times; and After step S405 is performed, step S406 is provided in which the surface of the wafer is alternately cleaned with DHF and DIO3.

[0011] In a fifth aspect, according to an embodiment of the present application, there is provided another method for cleaning a wafer, the method comprising: Step S501: Wetting the surface of the wafer with DIW; Step S502: spraying SC1 having a first set temperature onto the surface of the wafer; Step S503: continue spraying the SC1 having the first set temperature onto the surface of the wafer, and control the brush to scrub the surface of the wafer for a fifth set time; Step S504: spraying SC1 having a first set temperature onto the surface of the wafer, and controlling the brush to stop scrubbing the surface of the wafer until a sixth set time; Step S505: repeating steps S503 and S504 up to a fourth set number of times; and After step S505 is performed, step S506 is provided in which the surface of the wafer is alternately cleaned with DHF and DIO3.

[0012] According to an embodiment of the present application, a wafer cleaning apparatus is provided, comprising: a first spray module including at least one first spray head adapted to spray DIW onto the wafer to wet the surface of the wafer, and configured to spray DIW having a second set temperature onto the scrubbed wafer; a second spray module including a second spray head for spraying SC1 having a first set temperature onto the wafer; a first scrubbing module including a brush for scrubbing the surface of the wafer; and a first control module connected to the first spray module, the second spray module, and the first scrub module for performing the wafer cleaning method according to the first or fifth aspect.

[0013] According to an embodiment of the present application, there is provided another wafer cleaning apparatus, comprising: a third spray module including a third spray head for spraying DIW onto the wafer to wet the surface of the wafer; a fourth spray module including a fourth spray head for spraying SC1 having the first set temperature onto the wafer; a second scrubbing module including a brush for scrubbing the surface of the wafer; a megasonic module including a megasonic cleaning device for performing megasonic cleaning at a set power; and a second control module connected to the third spray module, the fourth spray module, the second scrub module, and the megasonic module for performing the wafer cleaning method according to the second, third, or fourth aspect.

[0014] Compared with the prior art, the wafer cleaning method and apparatus for cleaning the surface of a polished wafer provided by the embodiments of the present application adds a transition step of DIW spray cleaning or megasonic cleaning with a second set temperature during multiple consecutive scrubs, which sufficiently removes remaining materials on the wafer surface in a single scrub, effectively improving the cleaning effect of cleaning the polished wafer and solving the problem of low wafer cleaning effect in the prior art.

[0015] To make other features, objects and advantages of the present application more concise and easy to understand, the details of one or more embodiments of the present application are set forth in the drawings and description that follow. [Brief explanation of the drawings]

[0016] The accompanying drawings described herein are intended to provide a further understanding of the present application and are incorporated into and constitute a part of this application. The schematic embodiments and descriptions of the present application are for purposes of illustration and are not intended to unduly limit the present application. [Figure 1] FIG. 1 is a flowchart of a wafer cleaning method according to an embodiment of the present application. [Figure 2] FIG. 2 is a diagram showing data from a first experiment of a wafer cleaning method according to an embodiment of the present application. [Figure 3] FIG. 3 is a diagram showing data from a second experiment of a wafer cleaning method according to an embodiment of the present application. [Figure 4] FIG. 4 is a diagram showing data from a third experiment of a wafer cleaning method according to an embodiment of the present application. [Figure 5] FIG. 5 is a diagram showing data from a fourth experiment of the wafer cleaning method according to an embodiment of the present application. [Figure 6] FIG. 6 is a diagram showing data from a fifth experiment of the wafer cleaning method according to an embodiment of the present application. [Figure 7] FIG. 7 is a flowchart of a wafer cleaning method according to an embodiment of the present application. [Figure 8] FIG. 8 is a flowchart of a wafer cleaning method according to an embodiment of the present application. [Figure 9] FIG. 9 is a flowchart of a wafer cleaning method according to an embodiment of the present application. [Figure 10] FIG. 10 is a flowchart of a wafer cleaning method according to an embodiment of the present application. [Figure 11] FIG. 11 is a block diagram showing the structure of a wafer cleaning apparatus according to an embodiment of the present application. [Figure 12] FIG. 12 is a block diagram showing yet another structure of a wafer cleaning apparatus according to an embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0017] In order to make the objectives, technical solutions, and advantages of the present application more clearly understandable, the present application will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely examples of the present application and are not intended to limit the present application. Based on the embodiments provided in this application, all other embodiments obtained by those skilled in the art without any creative efforts fall within the protection scope of the present application.

[0018] Unless otherwise defined, technical or scientific terms used in this application have the common meanings understood by those skilled in the art of this application. In this application, the terms "a," "an," "one," "the," and the like do not imply a quantitative limitation but may refer to singular or plural. As used in this application, the terms "comprise," "include," "have," and variations thereof are intended to imply a non-exclusive inclusion. For example, a process, method, system, product, or apparatus comprising a series of steps or modules (units) is not limited to the listed steps or units, but may include additional steps or units not listed, or may include other steps or units inherent to the process, method, product, or apparatus. The terms "connected," "coupled," "coupled," and similar terms used in this application are not limited to physical or mechanical connections, but may include direct or indirect electrical connections. In this application, "plurality" means two or more. The term "and / or" describes a correspondence between related objects and indicates that a three-way relationship may exist. For example, "A and / or B" may refer to three cases. There are three: A only, A and B simultaneously, and B only. Terms such as "first," "second," and "third" referred to in this application are merely intended to distinguish between similar objects and do not represent a specific order of the objects.

[0019] After a wafer's surface is polished by chemical mechanical polishing (CMP), it is typically cleaned using a single-wafer contact cleaning process. This process is a cleaning method developed by Radio Corporation of America (RCA). The RCA cleaning method involves placing the wafer in a single-brush chamber, wetting the wafer's surface with DIW, spraying SC1 onto the wafer's surface to remove any remaining wax on the backside of the wafer, scrubbing the wafer's surface twice in succession with a brush to remove most of the remaining polishing solution, and finally rinsing the wafer's surface with DIW to complete the scrubbing process. The wafer is then transferred to a single-brush cleaning chamber, where it is alternately cleaned with DIO3 and DHF to remove the metal and native oxide layers on the wafer's surface, followed by DIW spraying and N2 blow-drying. Investigations revealed that after completing the cleaning process using the above-mentioned RCA cleaning process, the wafer had 600 LPDs (light point defects) of 0.12 μm or larger. The cleaning effect of the above RCA cleaning process is limited, and the cleaning effect of the wafer is low.

[0020] Therefore, in order to solve the above-mentioned problem of low wafer cleaning effect, an embodiment of the present application provides a wafer cleaning method for cleaning the surface of a polished wafer. Figure 1 is a flowchart of the wafer cleaning method according to an embodiment of the present application. As shown in Figure 1, the method includes: Step S101: Wetting the surface of the wafer with DIW; Step S102: spraying SC1 having a first set temperature onto the surface of the wafer; It is possible to remove particulate impurities and polymers on the wafer by spraying SC1 onto the surface of the wafer. Step S102, in which the cleaning solution of SC1 is a mixture of ammonia water, hydrogen peroxide, and water, and the volume ratio thereof is 1:2:50; Step S103: continuously spraying SC1 having a first set temperature onto the surface of the wafer and simultaneously controlling the brush to scrub the surface of the wafer; The SC1 having the first set temperature is sprayed onto the surface of the polished wafer, and at the same time, the brush is controlled to scrub the surface of the wafer, thereby further increasing the solubility of the organic amine and achieving the purpose of improving the cleaning effect of the wafer. Step S103: scrubbing the front and back surfaces of the wafer simultaneously with a brush; Step S104: performing a spray cleaning with DIW having a second set temperature for a first set time on the surface of the scrubbed wafer; Step S104: The first set temperature and the second set temperature are set according to the wafer cleaning process; Step S105: repeating steps S103 and S104 up to a first set number of times; and After step S105 is performed, step S106 is provided in which the surface of the wafer is alternately cleaned with DHF and DIO3.

[0021] Based on the above steps S101 to S106, the present application scrubs the polished wafer surface with a brush, then performs spray cleaning on the wafer surface using DIW at a second set temperature, and repeats the above steps a set number of times to increase the solubility of the organic amine polishing solution, further reducing the adsorption ability of particles on the wafer surface and improving the wafer cleaning effect.

[0022] In some embodiments, the temperature of the DIW having the second set temperature may be too high, which may affect the characteristics of the wafer and may cause some LPDNs (Light Point Defect Non-cleanable, which refers to particles that are recessed depressions on the wafer surface and cannot be cleaned or removed) to easily adsorb to the wafer surface. Therefore, in this embodiment, after performing step S105, the wafer surface is cleaned with DIW at room temperature, which avoids the problem of the wafer temperature being too high after spraying DIW at the second set temperature and further improves the cleaning effect of the wafer.

[0023] In some embodiments, the cleaning effect of the wafer is affected by factors set in the present application, such as the rotation speed of the wafer, the temperature and flow rate of the spray cleaning liquid, the duration of the spray cleaning, etc. Therefore, the present embodiment may also include the following method to further improve the cleaning effect of the wafer. In Method 1, in some embodiments, the second set temperature may be set between 35°C and 85°C.

[0024] As shown in Figure 2, the second set temperature can be adjusted under the assumption that other conditions remain unchanged. Based on Figure 2, it can be concluded that as the temperature increases, the solubility of the organic amine polishing solution can be further increased to a certain extent. In this way, the cleaning effect of the wafer can be further improved.

[0025] In Figure 2, the vertical axis represents the number of particles remaining on the wafer surface after spray cleaning with DIW at the second set temperature. LPD represents LPD (Light Point Defect) particles, and LPDN represents LPDN (Light Point Defect Non-cleanable) particles. The horizontal axis represents the temperature corresponding to the DIW sprayed at the second set temperature.

[0026] In Method 2, in some embodiments, the duration of the DIW spray cleaning at the second set temperature may be set to between 10 seconds and 120 seconds.

[0027] As shown in Figure 3, the DIW spray cleaning time at the second set temperature can be adjusted, assuming other conditions remain unchanged. Based on Figure 3, it can be concluded that as the spray time increases, the cleaning effect will gradually improve to a certain extent. Different spray times can be selected according to the requirements of different wafer processes, so that wafer cleaning efficiency can be achieved and the wafer cleaning effect can be improved at the same time.

[0028] In Figure 3, the vertical axis represents the number of particles remaining on the wafer surface after spray cleaning with DIW at the second set temperature. LPD represents LPD (Light Point Defect) particles, and LPDN represents LPDN (Light Point Defect Non-cleanable) particles. The horizontal axis represents the spray time of DIW at the second set temperature.

[0029] In some embodiments of Method 3, the number of cycles in steps S103 and S104 described above can be adjusted under the assumption that other conditions remain unchanged. As shown in FIG. 4, as the number of cycles increases, the cleaning effect of the wafer increases significantly. Therefore, to further improve the cleaning effect of the wafer, the first set number of cycles in step S105 can be increased. By setting the set number of cycles according to the actual process requirements, the requirements for cleaning efficiency and cleaning effect can be met.

[0030] In Figure 4, the vertical axis represents the number of particles remaining on the wafer surface after DIW spray cleaning at the second set temperature. LPD represents LPD (Light Point Defect) particles, and LPDN represents LPDN (Light Point Defect Non-cleanable) particles. The horizontal axis represents the number of cycle scrubs.

[0031] In Method 4, in some embodiments, the brush scrubbing speed may be adjusted between 6 mm / sec and 18 mm / sec.

[0032] Assuming other conditions remain unchanged, the brush scrubbing speed can be adjusted to further improve the wafer cleaning effect. As shown in Figure 5, as the brush scrubbing speed decreases, the wafer cleaning effect gradually improves.

[0033] In Figure 5, the vertical axis represents the number of particles remaining on the wafer surface after DIW spray cleaning at the second set temperature. LPD represents LPD (Light Point Defect) particles, and LPDN represents LPDN (Light Point Defect Non-cleanable) particles. The horizontal axis represents the brush scrubbing speed.

[0034] In Method 5, in some embodiments, the first set temperature of SC1 may be adjusted from 25° C. to 70° C. to improve the cleaning effect of the wafer.

[0035] Method 6 may, in some embodiments, be combined with Methods 1 through 5 above to achieve maximum cleaning effectiveness.

[0036] For example, assuming that the total wafer cleaning time and the first set number of times in step S105 are fixed, the brush scrubbing speed and the DIW spraying time at the second set temperature can be controlled. As shown in Table 1 below and Figure 6, when the brush scrubbing speed is 10 mm / sec, the brush scrubbing time and the DIW spraying time at the second set temperature are close to 1:1, and the cleaning efficiency is maximized.

[0037] [Table 1]

[0038] In Figure 6, the vertical axis represents the number of particles remaining on the wafer surface after DIW spray cleaning at the second set temperature. LPD represents LPD (Light Point Defect) particles, and LPDN represents LPDN (Light Point Defect Non-cleanable) particles. The horizontal axis represents the wafer number in Table 1.

[0039] In addition to the above-mentioned method, in some embodiments, the cleaning effect of the wafer can be improved by controlling the flow rate of the DIW at the second set temperature and the rotation speed of the wafer. The embodiments of the present application will not be illustrated one by one.

[0040] In the prior art, when alternating cleaning of a wafer with DHF and DIO3 is performed to ensure a satisfactory wafer cleaning effect, the wafer surface is alternately cleaned multiple times. However, in an embodiment of the present application, the polished wafer surface is scrubbed with a brush, and then the scrubbed wafer surface is spray-cleaned with DIW at a second set temperature. This process is repeated a set number of times to increase the solubility of the organic amine polishing solution. This also reduces the adsorption capacity of particles on the wafer surface. Furthermore, while ensuring improved cleaning efficiency and meeting production requirements, the number and duration of alternating cleaning with DHF and DIO3 can be appropriately reduced. This also reduces the amount of DHF used and the likelihood of defects in the DHF cleaning process. This means that etching of the wafer surface by DHF can be avoided.

[0041] Therefore, in order to solve the problem of poor wafer cleaning effect in the prior art, an embodiment of the present application further provides a wafer cleaning method for cleaning the surface of a polished wafer. Figure 7 is a flowchart of a wafer cleaning method according to an embodiment of the present application. As shown in Figure 7, the method includes: Step S201: Wetting the surface of the wafer with DIW; Step S202: spraying SC1 having a first set temperature onto the surface of the wafer; It is possible to remove particulate impurities and polymers on the wafer by spraying SC1 onto the surface of the wafer. Step S202, in which the cleaning solution of SC1 is a mixture of ammonia water, hydrogen peroxide, and water, and the volume ratio thereof is 1:2:50; Step S203: continuously spraying the SC1 having the first set temperature onto the surface of the wafer while simultaneously controlling the brush to scrub the surface of the wafer; The SC1 having the first set temperature is sprayed onto the polished wafer, and at the same time, the brush is controlled to scrub the surface of the wafer, thereby further increasing the solubility of the organic amine and achieving the purpose of improving the cleaning effect of the wafer; Step S203: scrubbing the front and back surfaces of the wafer simultaneously with a brush; Step S204: performing megasonic cleaning on the surface of the scrubbed wafer at a set power; In this embodiment, the cleaning solution for megasonic cleaning is still the first set temperature SC1, and the cleaning of organic amine can be enhanced by using megasonic vibration, thereby achieving the purpose of improving the cleaning effect and efficiency of the wafer. Step S204. Step S205: repeating steps S203 and S204 up to a second set number of times; and After performing step S205, the method includes step S206 of alternately cleaning the surface of the wafer with DHF and DIO3.

[0042] Based on the above steps S201 to S206, the surface of the polished wafer is scrubbed with a brush, and then megasonic cleaning is performed on the scrubbed surface of the wafer at a set power. After the above operations are repeated a set number of times, the polishing liquid remaining on the wafer surface is removed, thereby improving the cleaning effect of the wafer.

[0043] In some embodiments, before step S206, the surface of the wafer after step S205 may be cleaned with room temperature DIW.

[0044] In this embodiment, room temperature DIW is used to promote a decrease in the temperature of the wafer surface, thereby avoiding the problem that the temperature of the wafer surface becomes too high after spraying SC1 at the first set temperature, making it easier for LPDN to be adsorbed onto the wafer surface, and further improving the wafer cleaning effect.

[0045] In some embodiments, the set power is between 2 W and 10 W. In this embodiment, increasing the power can gradually increase the cleaning effect.

[0046] In some embodiments, the first set temperature of SC1 may be adjusted to between 25° C. and 70° C. to improve wafer cleaning efficiency.

[0047] In some embodiments, the second preset number of times in step S205 is set by a user. In this embodiment, as the second preset number of times increases, the cleaning effect of the wafer can be improved to a certain extent. Therefore, to further improve the cleaning effect of the wafer, the preset number of times in step S205 can be further increased. By setting the preset number of times according to actual process requirements, the requirements for cleaning efficiency and cleaning effect can be improved.

[0048] In some embodiments, the brush scrubbing speed is between 6 mm / s and 18 mm / s. In this embodiment, under the assumption that other conditions remain unchanged, the brush scrubbing speed can be adjusted to further improve the wafer cleaning effect. The effect is similar to that shown in FIG. 5. As the brush scrubbing speed decreases, the wafer cleaning effect can be gradually improved. A detailed description of this embodiment is omitted.

[0049] Therefore, in order to solve the problem of low wafer cleaning effect in the prior art, an embodiment of the present application further provides a wafer cleaning method for cleaning the surface of a polished wafer. Figure 8 is a flowchart of the wafer cleaning method according to an embodiment of the present application. As shown in Figure 8, the method includes: Step S301: Wetting the surface of the wafer with DIW; Step S302: spraying SC1 having a first set temperature onto the surface of the wafer; It is possible to remove particulate impurities and polymers on the wafer by spraying SC1 onto the surface of the wafer. Step S302, in which the cleaning solution of SC1 is a mixture of ammonia water, hydrogen peroxide, and water, and the volume ratio thereof is 1:2:50; Step S303: while continuing to spray SC1 having a first set temperature onto the surface of the wafer, control the brush to scrub the surface of the wafer and perform megasonic cleaning at a set power, wherein the time taken for the brush to scrub the surface of the wafer and perform megasonic cleaning at the set power is a second set time; The SC1 having a first set temperature is sprayed onto the surface of the polished wafer, and at the same time, the brush is controlled to scrub the surface of the wafer, and megasonic cleaning is performed at a set power, thereby further increasing the solubility of the organic amine, thereby achieving the purpose of improving the cleaning effect of the wafer; Brush scrubbing involves simultaneously scrubbing the front and back surfaces of the wafer, and In this embodiment, the cleaning of the organic amine can be enhanced by using the megasonic vibration in combination with SC1, thereby achieving the purpose of improving the cleaning effect and efficiency of the wafer. Step S303; After performing step S303, the method includes step S304 of alternately cleaning the surface of the wafer with DHF and DIO3.

[0050] Based on the above steps S301 to S304, by spraying SC1 at a first set temperature onto the surface of the wafer, simultaneously controlling the brush to scrub the surface of the wafer, and performing megasonic cleaning at a set power for a second set time, the polishing liquid remaining on the surface of the wafer can be removed, thereby solving the problem of low cleaning effect of polished wafers in the prior art and improving the cleaning effect of the wafer.

[0051] In some embodiments, before step S304, the surface of the wafer after step S303 may be cleaned with room temperature DIW.

[0052] In this embodiment, the room temperature DIW promotes a decrease in the temperature of the wafer surface, thereby avoiding the problem that the temperature of the wafer surface becomes too high after spraying SC1 at the first set temperature, making it easier for some of the LPDN to be adsorbed onto the wafer surface, and further improving the cleaning effect of the wafer.

[0053] In some embodiments, the set power is between 2 W and 10 W. In this embodiment, increasing the power can gradually increase the cleaning effect.

[0054] In some embodiments, the first set temperature of SC1 may be adjusted to between 25° C. and 70° C. to improve wafer cleaning efficiency.

[0055] In some embodiments, the second preset time is set by a user. In this embodiment, the user can set the time to improve the cleaning effect of the wafer. The second preset time can be set according to actual process requirements to improve the cleaning effect and cleaning efficiency.

[0056] In some embodiments, the brush scrubbing speed is between 6 mm / s and 18 mm / s. In this embodiment, under the assumption that other conditions remain unchanged, the brush scrubbing speed can be adjusted to further improve the wafer cleaning effect. The effect is similar to that shown in FIG. 5. As the brush scrubbing speed decreases, the wafer cleaning effect can be gradually improved. A detailed description of this embodiment is omitted.

[0057] In order to solve the problem of low wafer cleaning effect in the prior art, an embodiment of the present application further provides a wafer cleaning method for cleaning the surface of a polished wafer. Figure 9 is a flowchart of the wafer cleaning method according to an embodiment of the present application. As shown in Figure 9, the method includes: Step S401: Wetting the surface of the wafer with DIW; Step S402: spraying SC1 having a first set temperature onto the surface of the wafer; Step S402, which can remove particulate impurities and polymers on the wafer by spraying SC1 on the surface of the wafer; Step S403: continue spraying SC1 having a first set temperature onto the surface of the wafer, and for a third set time, control the brush to scrub the surface of the wafer and perform megasonic cleaning at a set power; Step S404: spraying SC1 having a first set temperature onto the surface of the wafer, controlling the brush to stop scrubbing the surface of the wafer, and stopping megasonic cleaning at the set power until a fourth set time; The solubility of the organic amine can be further increased, thereby achieving the purpose of improving the cleaning effect of the wafer; Step S404: scrubbing with a brush simultaneously scrubbing the front and back surfaces of the wafer; Step S405: repeating steps S403 and S404 up to a third set number of times; and After performing step S405, the method includes step S406 of alternately cleaning the surface of the wafer with DHF and DIO3.

[0058] In some embodiments, before step S406, the surface of the wafer after step S405 may be cleaned with room temperature DIW.

[0059] In this embodiment, the room temperature DIW promotes a decrease in the temperature of the wafer surface, thereby avoiding the problem that the temperature of the wafer surface becomes too high after spraying SC1 at the first set temperature, making it easier for some of the LPDN to be adsorbed onto the wafer surface, and further improving the cleaning effect of the wafer.

[0060] In some embodiments, the set power is between 2 W and 10 W. In this embodiment, increasing the power can gradually increase the cleaning effect.

[0061] In some embodiments, the first set temperature of SC1 may be adjusted to between 25° C. and 70° C. to improve wafer cleaning efficiency.

[0062] In some embodiments, the third preset time is set by a user. In this embodiment, the user can set the time to improve the cleaning effect of the wafer. The third preset time can be set according to actual process requirements to improve the cleaning effect and cleaning efficiency.

[0063] In some embodiments, the third preset number of times is set by a user. In this embodiment, as the number of cycles increases, the cleaning effect of the wafer can be improved to a certain extent. Therefore, to further improve the cleaning effect of the wafer, the third preset number of times in step S405 can be further increased. By setting the preset number of times according to actual process requirements, the requirements for cleaning effect and cleaning efficiency can be met.

[0064] In some embodiments, the fourth set time is set by a user, which can increase the efficiency of cleaning the wafer.

[0065] In some embodiments, the brush scrubbing speed is between 6 mm / s and 18 mm / s. In this embodiment, under the assumption that other conditions remain unchanged, the brush scrubbing speed can be adjusted to further improve the wafer cleaning effect. The effect is similar to that shown in FIG. 5. As the brush scrubbing speed decreases, the wafer cleaning effect can be gradually improved. A detailed description of this embodiment is omitted.

[0066] In order to solve the problem of low wafer cleaning effect in the prior art, an embodiment of the present application further provides a wafer cleaning method for cleaning the surface of a polished wafer. Figure 10 is a flowchart of the wafer cleaning method according to an embodiment of the present application. As shown in Figure 10, the method includes: Step S501: Wetting the surface of the wafer with DIW; Step S502: spraying SC1 having a first set temperature onto the surface of the wafer; It is possible to remove particulate impurities and polymers on the wafer by spraying SC1 onto the surface of the wafer. Step S502, in which the cleaning solution of SC1 is a mixture of ammonia water, hydrogen peroxide, and water, and the volume ratio thereof is 1:2:50; Step S503: continue spraying the SC1 having the first set temperature onto the surface of the wafer, and control the brush to scrub the surface of the wafer for a fifth set time; a step S504 of spraying SC1 having a first set temperature onto the surface of the wafer and controlling the brush to stop scrubbing the surface of the wafer until a sixth set time; The solubility of the organic amine can be further increased, thereby achieving the purpose of improving the cleaning effect of the wafer; Step S504: scrubbing the front and back surfaces of the wafer simultaneously with the brush; Step S505: repeating steps S503 and S504 up to a fourth set number of times; and After performing step S505, the method includes step S506 of alternately cleaning the surface of the wafer with DHF and DIO3.

[0067] In some embodiments, before step S506, the surface of the wafer after step S505 may be cleaned with room temperature DIW.

[0068] In this embodiment, the room temperature DIW promotes a decrease in the temperature of the wafer surface, thereby avoiding the problem that the temperature of the wafer surface becomes too high after spraying SC1 at the first set temperature, making it easier for some of the LPDN to be adsorbed onto the wafer surface, and further improving the cleaning effect of the wafer.

[0069] In some embodiments, the first set temperature of SC1 may be adjusted to between 25° C. and 70° C. to improve wafer cleaning efficiency.

[0070] In some embodiments, the fifth preset time is set by a user, and the user can set the time to improve the cleaning effect of the wafer. By setting the fifth preset time according to actual process requirements, the cleaning effect and cleaning efficiency can be improved.

[0071] In some embodiments, the fourth preset number of times is set by a user. In this embodiment, as the number of cycles increases, the cleaning effect of the wafer can be improved to a certain extent. Therefore, to further improve the cleaning effect of the wafer, the fourth preset number of times in step S505 can be further increased. Setting the preset number of times according to actual process requirements can improve the cleaning effect and cleaning efficiency.

[0072] In some embodiments, the sixth preset time is set by a user, and the user can set the time to improve the cleaning effect of the wafer. By setting the sixth preset time according to actual process requirements, the cleaning effect and cleaning efficiency can be improved.

[0073] In some embodiments, the brush scrubbing speed is between 6 mm / s and 18 mm / s. In this embodiment, under the assumption that other conditions remain unchanged, the brush scrubbing speed can be adjusted to further improve the wafer cleaning effect. The effect is similar to that shown in FIG. 5. As the brush scrubbing speed decreases, the wafer cleaning effect can be gradually improved. A detailed description of this embodiment is omitted.

[0074] After the wafer has been cleaned, the surface of the wafer may be dried with a dry gas such as helium or nitrogen.

[0075] Based on the above-mentioned embodiments, in this embodiment of the present application, by adding a transition step during multiple consecutive scrubs, the remaining material on the wafer surface can be sufficiently removed in one scrub, and the cleaning effect of the single wafer contact cleaning process on the polished wafer can be effectively improved.

[0076] The present application also provides a wafer cleaning apparatus for cleaning the surface of a polished wafer. This apparatus is used to realize the above-described embodiments. The above-described description will be omitted. The terms "module," "unit," "subunit," and the like used below may refer to a combination of software and / or hardware that implements a predetermined function.

[0077] 11 is a block diagram showing the structure of a wafer cleaning apparatus for cleaning the surface of a polished wafer according to an embodiment of the present application. As shown in FIG. 11, the apparatus includes: a first spray module 111 including at least one first spray head adapted to spray DIW onto the surface of the wafer to wet the surface of the wafer and adapted to spray DIW having a second set temperature onto the scrubbed wafer; a second spray module 112 including a second spray head for spraying SC1 having a first set temperature onto the surface of the wafer; a first scrubbing module 113 including a brush for scrubbing the surface of the wafer; and The wafer cleaning method includes a first control module 114 connected to a first spray module 111, a second spray module 112, and a first scrub module 113 for performing the wafer cleaning method of spraying DIW at the above-mentioned second set temperature.

[0078] Alternatively, one first spray head may be provided to spray DIW onto the surface of the wafer to wet the surface of the wafer. Alternatively, DIW having a second set temperature may be sprayed onto the wafer after scrubbing. Furthermore, two first spray heads may be provided to achieve both functions. If necessary, at least one first spray head, whether a single spray head or an additional spray head, may be configured to spray DIW at the second set temperature onto the wafer after scrubbing. However, if there is no need to spray DIW at the second set temperature, the configuration for this operation may be omitted, and, for example, only a single spray head may be provided.

[0079] In some embodiments, the first set temperature may be between 25°C and 70°C.

[0080] In some embodiments, the second set temperature may be between 35°C and 85°C.

[0081] In some embodiments, the duration of the DIW spray cleaning at the second set temperature may be between 10 seconds and 120 seconds.

[0082] In some embodiments, the brush scrubbing speed may be set between 6 mm / sec and 18 mm / sec.

[0083] 12 is a block diagram showing another structure of a wafer cleaning apparatus for cleaning the surface of a polished wafer according to an embodiment of the present application. As shown in FIG. 12, the apparatus includes: a third spray module 121 including a third spray head for spraying DIW onto the surface of the wafer to wet the surface of the wafer; a fourth spray module 122 including a fourth spray head for spraying SC1 having a first set temperature onto the surface of the wafer; a second scrubbing module 123 including a brush for scrubbing the surface of the wafer; a megasonic module 124 including a megasonic cleaning device for performing megasonic cleaning at a set power; The apparatus includes a third spray module 121, a fourth spray module 122, a second scrub module 123, and a second control module 125 connected to the megasonic module 124 for performing the above-mentioned wafer cleaning method using megasonic cleaning.

[0084] In some embodiments, the first set temperature may be between 25°C and 70°C.

[0085] In some embodiments, the brush scrubbing speed may be set between 6 mm / sec and 18 mm / sec.

[0086] In some embodiments, the set power may be between 2W and 10W.

[0087] It should be understood by those skilled in the art that the technical features of the above-described embodiments can be arbitrarily combined. For the sake of brevity, not all possible combinations of the technical features of the above-described embodiments are described. However, as long as there is no contradiction in the combination of technical features, these technical features shall be deemed to be within the scope of this specification.

[0088] The above-described embodiments merely represent some embodiments of the present application. Although the description is relatively specific and detailed, it should not be understood as limiting the scope of the present invention. It should be noted that a person skilled in the art can make some modifications and improvements without departing from the concept of the present application, and all such modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application should be as follows:

Claims

1. A wafer cleaning method for cleaning a surface of a polished wafer, comprising: Step S101: Wetting the surface of the wafer with DIW; Step S102: spraying SC1 having a first set temperature on the surface of the wafer; Step S103: continuously spraying the SC1 having the first set temperature onto the surface of the wafer while simultaneously controlling a brush to scrub the surface of the wafer; Step S104: spray cleaning the scrubbed surface of the wafer with DIW at a second set temperature for a first set time; Step S105 of repeating steps S103 and S104 up to a first set number of times; and After performing step S105, the surface of the wafer is treated with DHF and DIO. ３ The wafer cleaning method includes a step S106 of alternately cleaning the wafer with the above.

2. 2. The wafer cleaning method according to claim 1, further comprising, before step S106, cleaning the surface of the wafer with DIW at room temperature after step S105 is performed.

3. 2. The wafer cleaning method of claim 1, wherein the first set temperature is between 25°C and 70°C.

4. 2. The wafer cleaning method of claim 1, wherein the first set time is between 10 seconds and 120 seconds.

5. 2. The wafer cleaning method of claim 1, wherein the second set temperature is between 35°C and 85°C.

6. 2. The wafer cleaning method of claim 1, wherein the brush scrubbing speed is between 6 mm / sec and 18 mm / sec.

7. A wafer cleaning method for cleaning a surface of a polished wafer, comprising: Step S201: Wetting the surface of the wafer with DIW; Step S202: spraying SC1 having a first set temperature on the surface of the wafer; Step S203: continuously spraying the SC1 having the first set temperature onto the surface of the wafer while simultaneously controlling a brush to scrub the surface of the wafer; Step S204: performing megasonic cleaning on the scrubbed surface of the wafer at a set power; Step S205: repeating steps S203 and S204 up to a second set number of times; and After performing step S205, the surface of the wafer is treated with DHF and DIO. ３ The wafer cleaning method includes a step S206 of alternately cleaning with the above.

8. 8. The wafer cleaning method according to claim 7, further comprising, before step S206, cleaning the surface of the wafer with DIW at room temperature after step S205 is performed.

9. 8. The wafer cleaning method according to claim 7, wherein the set power is between 2 W and 10 W.

10. 8. The wafer cleaning method of claim 7, wherein the first set temperature is between 25°C and 70°C.

11. 8. The wafer cleaning method of claim 7, wherein the brush scrubbing speed is between 6 mm / sec and 18 mm / sec.

12. A wafer cleaning method for cleaning a surface of a polished wafer, comprising: Step S301: Wetting the surface of the wafer with DIW; Step S302: spraying SC1 having a first set temperature on the surface of the wafer; Step S303: Continue spraying the SC1 having the first set temperature onto the surface of the wafer, while simultaneously controlling a brush to scrub the surface of the wafer, and perform megasonic cleaning at a set power until a second set time; and After performing step S303, the surface of the wafer is washed with DHF and DIO. ３ The wafer cleaning method further comprises a step S304 of alternately cleaning the wafer with the above-mentioned.

13. 13. The wafer cleaning method according to claim 12, further comprising, before step S304, cleaning the surface of the wafer with DIW at room temperature after step S303 is performed.

14. 13. The wafer cleaning method of claim 12, wherein the set power is between 2 W and 10 W.

15. 13. The wafer cleaning method of claim 12, wherein the first set temperature is between 25°C and 70°C.

16. 13. The method of claim 12, wherein the brush scrubbing speed is between 6 mm / sec and 18 mm / sec.

17. A wafer cleaning method for cleaning a surface of a polished wafer, comprising: Step S401: Wetting the surface of the wafer with DIW; Step S402: spraying SC1 having a first set temperature on the surface of the wafer; Step S403: while continuing to spray SC1 having the first set temperature onto the surface of the wafer, for a third set time, control a brush to scrub the surface of the wafer and perform megasonic cleaning at a set power; Step S404: spraying SC1 having the first set temperature onto the surface of the wafer, controlling the brush to stop scrubbing the surface of the wafer, and stopping the megasonic cleaning at the set power until a fourth set time; Step S405: repeating steps S403 and S404 up to a third set number of times; and After performing step S405, the surface of the wafer is treated with DHF and DIO. ３ The wafer cleaning method includes a step S406 of alternately cleaning with the above.

18. 18. The wafer cleaning method of claim 17, further comprising cleaning the surface of the wafer with DIW at room temperature after performing step S405 before step S406.

19. 18. The wafer cleaning method of claim 17, wherein the set power is between 2 W and 10 W.

20. 18. The wafer cleaning method of claim 17, wherein the first set temperature is between 25°C and 70°C.

21. 18. The method of claim 17, wherein the brush scrubbing speed is between 6 mm / sec and 18 mm / sec.

22. A wafer cleaning method for cleaning a surface of a polished wafer, comprising: Step S501: Wetting the surface of the wafer with DIW; Step S502: spraying SC1 having a first set temperature onto the surface of the wafer; Step S503: continuing to spray the SC1 having the first set temperature onto the surface of the wafer, and controlling a brush to scrub the surface of the wafer for a fifth set time; Step S504: spraying SC1 having the first set temperature onto the surface of the wafer, and controlling the brush to stop scrubbing the surface of the wafer until a sixth set time; Step S505 of repeating steps S503 and S504 up to a fourth set number of times; and After performing step S505, the surface of the wafer is treated with DHF and DIO. ３ and step S506 of alternately washing.

23. 23. The wafer cleaning method of claim 22, further comprising, before step S506, cleaning the surface of the wafer with DIW at room temperature after step S505 is performed.

24. 23. The wafer cleaning method of claim 22, wherein the first set temperature is between 25°C and 70°C.

25. 23. The method of claim 22, wherein the brush scrubbing speed is between 6 mm / sec and 18 mm / sec.

26. A wafer cleaning apparatus for cleaning the surface of a polished wafer, comprising: a first spray module including at least one first spray head configured to spray DIW onto the surface of the wafer to wet the surface of the wafer and configured to spray DIW having a second set temperature onto the scrubbed surface of the wafer; a second spray module including a second spray head for spraying SC1 having a first set temperature onto the surface of the wafer; a first scrubbing module including a brush for scrubbing the surface of the wafer; and 26. A wafer cleaning apparatus comprising: a first control module connected to the first spray module, the second spray module, and the first scrub module for performing the wafer cleaning method of any one of claims 1 to 6 or claims 22 to 25.

27. 27. The wafer cleaning apparatus of claim 26, wherein the first set temperature is between 25°C and 70°C.

28. 27. The wafer cleaning apparatus of claim 26, wherein the second set temperature is between 35°C and 85°C.

29. 27. The wafer cleaning apparatus of claim 26, wherein the time for spray cleaning with DIW at the second set temperature is between 10 seconds and 120 seconds.

30. 27. The wafer cleaning apparatus of claim 26, wherein the scrubbing speed of the brush is set between 6 mm / sec and 18 mm / sec.

31. A wafer cleaning apparatus for cleaning the surface of a polished wafer, comprising: a third spray module including a third spray head for spraying DIW onto the surface of the wafer to wet the surface of the wafer; a fourth spray module including a fourth spray head for spraying SC1 having a first set temperature onto the surface of the wafer; a second scrubbing module including a brush for scrubbing the surface of the wafer; a megasonic module including a megasonic cleaning device for performing megasonic cleaning at a set power; 22. A wafer cleaning apparatus comprising: a second control module connected to the third spray module, the fourth spray module, the second scrub module, and the megasonic module for performing the wafer cleaning method of any one of claims 7 to 11, claims 12 to 16, or claims 17 to 21.

32. 32. The wafer cleaning apparatus of claim 31, wherein the first set temperature is between 25°C and 70°C.

33. 32. The wafer cleaning apparatus of claim 31, wherein the scrubbing speed of the brush is set between 6 mm / sec and 18 mm / sec.

34. 32. The wafer cleaning apparatus of claim 31, wherein the set power is between 2W and 10W.

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