Wafer back corrosive liquid spraying pipeline, corrosive liquid spraying pipeline and cleaning equipment
By designing a structure for the corrosion liquid jet pipeline on the back of the wafer, including nozzles, switch valves, regulating valves, main pipelines and branch pipelines, the problem of bubbles in the corrosion liquid pipeline on the back of the wafer is solved, and the stability of the corrosion liquid flow rate and the effective removal of the copper plating on the edges and back of the wafer is achieved.
Patent Information
- Application Number
- CN202311280225.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-28
- Publication Date
- 2025-03-28
AI Technical Summary
In the prior art, there is a bubble problem in the corrosion liquid pipeline on the back of the wafer, resulting in unstable corrosion liquid flow, affecting the removal effect of the copper plating on the edge of the wafer and the back of the wafer.
A corrosion liquid injection pipeline on the back of the wafer is designed, including nozzles, switch valves, regulating valves, main pipelines and branch pipelines. The regulating valves are kept open when the switch valve is closed, and the corrosion liquid in the main pipeline flows through the branch pipeline to the nozzle with a preset flow rate, thereby avoiding the corrosion liquid decomposing and generating bubbles when it is not used in the pipeline for a long time.
It effectively avoids the generation of bubbles when the corrosion liquid is not used in the pipeline for a long time, maintains the stability of the corrosion liquid flow, improves the removal effect of copper plating on the edges and back of the wafer, and reduces the product defect rate.
Smart Images
Figure CN119725142A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of wafer cleaning, and in particular to a wafer backside etching liquid injection pipeline, an etching liquid injection pipeline and a cleaning device. Background Art
[0002] As the speed of integrated circuits increases, the previous aluminum process technology can no longer meet the requirements of electroplating technology. Since copper has good thermal conductivity, electrical conductivity and low resistance, copper interconnection technology has gradually developed into the mainstream semiconductor integrated circuit interconnection technology. In addition, copper electroplating has the characteristics of simple process and strong operability, so copper electroplating has also become the main process for preparing copper film in copper interconnection technology.
[0003] In the copper manufacturing process, copper electroplating equipment is not only used to obtain a uniform copper film without holes, but also needs to clean the edge copper and back copper of the wafer after copper electroplating to cooperate with the subsequent chemical mechanical polishing (CMP) process. The edge and back copper are cleaned because the copper film on the edge of the wafer after copper electroplating is easy to fall off, and these fallen copper films will damage the wafer surface and seriously affect production.
[0004] The prior art method for cleaning a wafer after copper electroplating is as follows: placing the copper electroplated wafer in a cleaning device, and directly performing an edge removal process and a back cleaning process, that is, using a high-speed etching liquid to clean the copper plating on the edge of the wafer and the copper plating on the back of the wafer, and removing the copper plating on the edge and back of the wafer. The high-speed etching liquid is usually an acid that can react with copper. In order to completely remove the copper on the edge of the wafer and the copper on the back, the cleaning device is usually equipped with a high-speed etching liquid injection pipeline for the front side of the wafer and a high-speed etching liquid injection pipeline for the back side of the wafer.
[0005] As we all know, it is particularly important to maintain a stable flow rate of high-speed etching liquid during the process, otherwise it will directly affect the removal effect of the copper plating on the edge and back of the wafer, and may eventually cause problems such as copper residue and edge corrosion, which will seriously affect the product yield. Studies have found that bubbles in the high-speed etching liquid injection pipeline are the main cause of unstable flow during the process. When bubbles pass through the front high-speed etching liquid flow meter, the flow meter reading in the front high-speed etching liquid pipeline will be inaccurate, thus affecting the edge cleaning process. Summary of the invention
[0006] The embodiments of the present application provide a wafer back side etching liquid injection pipeline, an etching liquid injection pipeline and a cleaning device, so as to at least solve the problem of bubbles in the wafer back side etching liquid pipeline in the related art.
[0007] In a first aspect, an embodiment of the present application provides a wafer back side etching liquid injection pipeline for injecting etching liquid onto the back side of the wafer, comprising: a nozzle, a switch valve, a regulating valve, a main pipeline and a branch pipeline, wherein the nozzle is arranged at the end of the main pipeline, the switch valve is arranged on the main pipeline, one end of the branch pipeline is arranged at the first end of the switch valve, the other end of the branch pipeline is arranged between the second end of the switch valve and the nozzle, and the regulating valve is arranged on the branch pipeline, wherein:
[0008] The regulating valve is used to remain open when the switch valve is closed, and to allow the corrosive liquid in the main pipeline to flow to the nozzle through the branch pipeline at a first preset flow rate.
[0009] In some of the embodiments, the regulating valve is further configured to remain open when the switch valve is open, and to allow the corrosive liquid in the main pipeline to flow to the nozzle through the branch pipeline at a first preset flow rate.
[0010] In some of the embodiments, it further includes: a flow meter, which is arranged at the first end of the switch valve and is used to detect the flow rate of the corrosive liquid in the main pipeline.
[0011] In some of the embodiments, it further includes: a flow alarm, wherein the flow alarm is used to sound an alarm when the flow meter detects that the flow rate of the corrosive liquid in the main pipeline is not within a preset flow range.
[0012] In some embodiments, it also includes: a bubble detector and a bubble alarm, wherein the bubble detector is arranged at the first end of the switch valve to detect whether there are bubbles in the main line, and the bubble alarm is used to alarm when the bubble detector detects bubbles stored in the main line.
[0013] In the second aspect, an embodiment of the present application also provides a corrosive liquid injection pipeline, including a wafer front side corrosive liquid injection pipeline and a wafer back side corrosive liquid injection pipeline as described in the first aspect, wherein the wafer front side corrosive liquid injection pipeline is used to spray corrosive liquid onto the front edge of the wafer.
[0014] In some of the embodiments, the regulating valve remains open during the operation of the wafer front side etching liquid injection pipeline, and the regulating valve is closed when the wafer front side etching liquid injection pipeline stops working.
[0015] In a third aspect, an embodiment of the present application further provides a wafer cleaning device, comprising the etching liquid injection pipeline as described in the second aspect.
[0016] In some of the embodiments, the wafer cleaning equipment further includes a corrosive liquid storage tank for providing corrosive liquid to the corrosive liquid injection pipeline.
[0017] Compared with the prior art, the wafer back side etching liquid injection pipeline provided in the embodiment of the present application is provided with a nozzle, a switch valve, a regulating valve, a main pipeline and a branch pipeline. The regulating valve is used to keep it open when the switch valve is closed, and the etching liquid in the main pipeline flows to the nozzle through the branch pipeline at a first preset flow rate. In this way, the back side etching liquid injection pipeline can still maintain circulation when the switch valve is closed, thereby avoiding the problem that the etching liquid retained in the pipeline will decompose and generate a large number of bubbles when the etching liquid is not used for a long time.
[0018] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0020] Figure 1 It is a schematic diagram of the structure of the etching liquid pipeline on the back side of the wafer;
[0021] Figure 2 is a schematic structural diagram of a wafer backside etching liquid pipeline according to an embodiment of the present application;
[0022] Figure 3 It is a schematic diagram of the structure of a cleaning device according to an embodiment of the present application. DETAILED DESCRIPTION
[0023] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for ordinary technicians in the field related to the contents disclosed in the present application, some changes such as design, manufacturing or production based on the technical contents disclosed in the present application are only conventional technical means, and should not be understood as insufficient contents disclosed in the present application.
[0024] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation, and may represent the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units that are not listed, or may also include other steps or units inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" involved in this application refers to greater than or equal to two. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships, for example, "A and / or B" can represent: A exists alone, A and B exist at the same time, and B exists alone. The terms "first", "second", "third" and the like involved in the present application are merely used to distinguish similar objects and do not represent a specific ordering of the objects.
[0025] To facilitate the description of the wafer backside etching liquid pipeline of the present application, the cleaning equipment of the present application is first described.
[0026] See also Figure 3 , Figure 3 The cleaning device of one embodiment of the present application is illustrated, and the cleaning device includes an etching liquid storage tank 40, a wafer front etching liquid injection pipeline 20, a wafer back etching liquid injection pipeline 10, and a cleaning chamber 50. In this embodiment, when the back of the wafer 30 is normally cleaned, the high-speed etching liquid is supplied from the etching liquid storage tank 40 by a pump, and reaches the nozzle 11 along the etching liquid injection pipeline 10 on the back of the wafer, thereby cleaning the back of the wafer 30. Secondly, when the front edge of the wafer 30 is normally cleaned, the high-speed etching liquid is supplied from the etching liquid storage tank 40 by a pump, and reaches the nozzle 21 along the etching liquid injection pipeline 20 on the front of the wafer, thereby cleaning the front edge of the wafer 30. In the above manner, the cleaning of the front edge and the back of the wafer 30 is achieved.
[0027] See also Figure 1 , Figure 1 A schematic diagram of the structure of a back-side etching liquid injection pipeline 60 is shown. Figure 1As shown, the back-side etching liquid injection pipeline 60 includes: a nozzle 61, a switch valve 62, a main pipeline 63 and a flow meter 64. After research, it was found that most of the bubbles in the high-speed etching liquid pipeline are generated in the back-side high-speed etching liquid pipeline, because the use frequency of the back-side high-speed etching liquid is not as high as that of the front-side high-speed etching liquid. When not in use, the switch valve 62 of the back-side etching liquid injection pipeline 60 is closed, and the high-speed etching liquid does not circulate in the main pipeline 63 for a long time. The etching liquid inside, such as hydrogen peroxide, will decompose to generate a large number of bubbles, which will cause the high-speed etching liquid to be unstable in the process, affecting the copper removal effect on the front edge and back of the wafer 30. Specifically, during the cleaning process of the front edge and back of the wafer, a main pipeline is usually used to supply etching liquid to the etching liquid injection pipeline on the back of the wafer and the etching liquid injection pipeline on the front of the wafer. Since the usage frequency of the etching liquid injection pipeline on the back side of the wafer is not as high as that of the etching liquid injection pipeline on the front side of the wafer, there is a situation where the switch valve 62 of the etching liquid injection pipeline 60 on the back side of the wafer is closed while the etching liquid injection pipeline on the front side of the wafer is still open and working. At this time, the high-speed etching liquid does not flow in the main pipeline 63 for a long time, and the etching liquid in it, such as hydrogen peroxide, will decompose to generate a large number of bubbles, and flow back into the main pipeline and the etching liquid injection pipeline on the front side of the wafer, thereby affecting the copper removal effect on the front edge and back side of the wafer.
[0028] Therefore, in order to solve the problem of bubbles in the wafer back side etching liquid pipeline, the present application provides a wafer back side etching liquid injection pipeline 10, which is applied to a wafer cleaning device and is used to inject etching liquid to the back side of a wafer 30. Figure 2 and Figure 3 As shown, the wafer backside etching liquid injection pipeline 10 of this embodiment includes: a nozzle 11, a switch valve 12, a regulating valve 15, a main pipeline 13 and a branch pipeline 14, the nozzle 11 is arranged at the end of the main pipeline 13, the switch valve 12 is arranged on the main pipeline 13, one end of the branch pipeline 14 is arranged at the first end of the switch valve 12, and the other end of the branch pipeline 14 is arranged between the second end of the switch valve 12 and the nozzle 11, and the regulating valve 15 is arranged on the branch pipeline 14, wherein the regulating valve 15 is used to remain open when the switch valve 12 is closed, and to make the etching liquid in the main pipeline 13 flow to the nozzle 11 through the branch pipeline 14 at a first preset flow rate, and further flow out from the nozzle 11 to the cleaning chamber 50. Reference Figure 2 , the end of the switch valve 12 close to the nozzle 11 is recorded as its second end, and the other end is recorded as its first end.
[0029] In this embodiment, the regulating valve 15 is used to remain open when the switch valve 12 is closed, and the etching liquid in the main pipeline 13 flows to the nozzle 11 through the branch pipeline 14 at a first preset flow rate, so that the back etching liquid injection pipeline 10 can still maintain circulation when the switch valve 12 is closed, thereby avoiding the problem that the hydrogen peroxide retained in the etching liquid in the pipeline will decompose and generate a large number of bubbles when the etching liquid is not used for a long time.
[0030] It should be noted that the first preset flow rate is set by the user according to the actual cleaning process requirements of the wafer 30. Assuming that when the back side of the wafer is cleaned, the flow rate of the back side etching liquid injection pipeline 10 is the process flow rate, then the first preset flow rate should be less than the process flow rate and as small as possible, so that the etching liquid only flows out through the nozzle 11, and is not sprayed onto the back side of the wafer, and the consumption of the etching liquid during this period is minimized.
[0031] Furthermore, the regulating valve 15 in this embodiment may be a manual regulating valve 15 , which can accurately adjust the actual flow rate according to the user's own experience.
[0032] In this embodiment, the regulating valve 15 is also used to remain open when the switch valve 12 is open, and to allow the etching liquid in the main pipeline 13 to flow to the nozzle 11 through the branch pipeline 14 at a first preset flow rate. According to this embodiment, whether the switch valve 12 is open or closed, the regulating valve 15 remains open, avoiding the switch control of the regulating valve 15, making the control method simpler. At the same time, when the switch valve 12 is open, since the first preset flow rate is much smaller than the process flow rate, there is almost no effect on the wafer back cleaning process.
[0033] At the same time, after the bubbles are eliminated in the above manner, it is also possible to avoid the problem of the cleaning equipment being stopped due to an alarm, thereby reducing the production capacity of the cleaning equipment.
[0034] Continue to see Figure 2 In this embodiment, the wafer backside etching liquid injection pipeline 10 further includes: a flow meter 16, which is arranged at the first end of the switch valve 12 away from the nozzle 11, and is used to detect the flow rate of the etching liquid in the main pipeline 13. By setting the flow meter 16, the flow rate in the main pipeline 13 can be monitored in real time.
[0035] In some embodiments, the wafer backside etching liquid injection pipeline 10 further includes: a flow alarm (not shown), which is used to sound an alarm when the flow meter 16 detects that the etching liquid flow in the main pipeline 13 is not within a preset flow range. Based on the alarm, when the flow meter 16 detects that the etching liquid flow in the main pipeline 13 is not within a preset flow range, the alarm is sounded, and corresponding processing can be performed according to the alarm to avoid excessive or insufficient flow that affects the cleaning effect of the wafer 30.
[0036] It should be noted that the preset flow rate interval may be within a range of 10% of the flow rate value preset by the user.
[0037] In some embodiments, the wafer backside etching liquid injection pipeline further includes: a bubble detector (not shown) and a bubble alarm (not shown), the bubble detector is disposed at the first end of the switch valve 12, and is used to detect whether there are bubbles in the main pipeline 13, and the bubble alarm is used to alarm when the bubble detector detects that there are bubbles in the main pipeline 13. In this embodiment, based on the bubble detector and the bubble alarm, real-time monitoring of bubbles and alarming of bubbles can be achieved.
[0038] Specifically, the bubble detector can be installed on the main line 13, and obtain the corrosive liquid from the main line 13, perform bubble detection on the obtained corrosive liquid, and when bubbles are detected, transmit the bubble information to the bubble alarm, and the bubble alarm alarms according to the bubble information.
[0039] Continue to see Figure 3 The embodiment of the present application also provides a corrosive liquid injection pipeline, including a wafer front corrosive liquid injection pipeline 20 and a wafer back corrosive liquid injection pipeline 10. The wafer front corrosive liquid injection pipeline 20 is used to spray corrosive liquid on the front edge of the wafer. By setting the wafer back corrosive liquid injection pipeline 10 in the corrosive liquid injection pipeline as follows Figure 2 The wafer back side etching liquid injection pipeline 10 shown in the figure can keep the back side etching liquid injection pipeline 10 flowing when the switch valve 12 is closed, thereby preventing the etching liquid remaining in the pipeline from being decomposed to generate a large number of bubbles when the etching liquid is not used for a long time, such as hydrogen peroxide, and affecting the cleaning process of the front edge of the wafer 30 by the wafer front side etching liquid injection pipeline 20.
[0040] During the wafer cleaning process, the etching liquid in the storage tank 40 is provided to the etching liquid injection pipeline 20 on the front side of the wafer and the etching liquid injection pipeline 10 on the back side of the wafer through the main pipeline 70. In this embodiment, the regulating valve 15 is kept open during the operation of the etching liquid injection pipeline 20 on the front side of the wafer, and the regulating valve 15 is closed when the etching liquid injection pipeline 20 on the front side of the wafer finishes working. In this way, the etching liquid, such as hydrogen peroxide, is avoided from being decomposed to generate a large number of bubbles and flowing back to the etching liquid injection pipeline 20 on the front side of the wafer when the etching liquid is not used for a long time, thereby improving the wafer cleaning effect.
[0041] The present application also provides a wafer cleaning device, comprising: Figure 3The etching liquid injection pipeline shown in the figure includes a wafer backside etching liquid injection pipeline 10 and a wafer frontside etching liquid injection pipeline 20. By setting the etching liquid injection pipeline, the backside etching liquid injection pipeline 10 can be kept flowing when the switch valve 12 is closed, thereby preventing the etching liquid, such as hydrogen peroxide, from decomposing and generating a large number of bubbles when the etching liquid is not used for a long time in the pipeline, thereby affecting the cleaning process of the wafer frontside etching liquid injection pipeline 20 on the front edge of the wafer 30.
[0042] Continue to see Figure 3 In this embodiment, the cleaning device further includes a corrosive liquid storage tank 40 for providing the corrosive liquid to the corrosive liquid injection pipeline.
[0043] Those skilled in the art should understand that the technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0044] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. 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 application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.
Claims
1. A wafer backside etching liquid injection pipeline, used for injecting etching liquid onto the backside of a wafer, characterized in that: include: A nozzle, a switch valve, a regulating valve, a main pipeline and a branch pipeline, wherein the nozzle is arranged at the end of the main pipeline, the switch valve is arranged on the main pipeline, one end of the branch pipeline is arranged at the first end of the switch valve, the other end of the branch pipeline is arranged between the second end of the switch valve and the nozzle, and the regulating valve is arranged on the branch pipeline, wherein: The regulating valve is used to remain open when the switch valve is closed, and to allow the corrosive liquid in the main pipeline to flow to the nozzle through the branch pipeline at a first preset flow rate.
2. The wafer backside etching liquid injection pipeline according to claim 1, characterized in that: The regulating valve is also used to remain open when the switch valve is open, and to allow the corrosive liquid in the main pipeline to flow to the nozzle through the branch pipeline at a first preset flow rate.
3. The wafer backside etching liquid injection pipeline according to claim 1, characterized in that: Also includes: A flow meter is arranged at the first end of the switch valve and is used to detect the flow rate of the corrosive liquid in the main pipeline.
4. The wafer backside etching liquid injection pipeline according to claim 3, characterized in that: Also includes: A flow alarm is used to sound an alarm when the flow meter detects that the flow rate of the corrosive liquid in the main pipeline is not within a preset flow range.
5. The wafer backside etching liquid injection pipeline according to claim 1, characterized in that: Also includes: A bubble detector and a bubble alarm, wherein the bubble detector is arranged at the first end of the switch valve and is used to detect whether there are bubbles in the main pipeline, and the bubble alarm is used to alarm when the bubble detector detects bubbles stored in the main pipeline.
6. A corrosive liquid injection pipeline, characterized in that: It comprises a wafer front side etching liquid injection pipeline and a wafer back side etching liquid injection pipeline as claimed in any one of claims 1 to 5, wherein the wafer front side etching liquid injection pipeline is used for injecting etching liquid toward the front side edge of the wafer.
7. The corrosive liquid injection pipeline according to claim 6, characterized in that: During the operation of the wafer front side etching liquid injection pipeline, the regulating valve remains open, and when the wafer front side etching liquid injection pipeline finishes operation, the regulating valve is closed.
8. A wafer cleaning device, characterized in that: It comprises the corrosive liquid injection pipeline as claimed in any one of claims 6 to 7.
9. The wafer cleaning equipment according to claim 8, characterized in that: It also includes a corrosive liquid storage tank, which is used to provide corrosive liquid to the corrosive liquid injection pipeline.