Semiconductor wafer batch processing cleaning apparatus and chemical bath pressure control device therefor

Abstract

This invention discloses a batch cleaning equipment and its chemical bath pressure control device, comprising n sets of chemical agent supply pipelines disposed at different positions at the bottom of the chemical bath, and n sets of liquid level pressure sensors disposed on the upper side of the chemical bath; wherein n is a positive integer greater than or equal to 3; and the liquid level pressure sensors are configured one-to-one with the chemical agent supply pipelines; the n sets of liquid level pressure sensors are used to detect the pressure values ​​at different positions inside the chemical bath; based on the detected pressure values ​​at different positions inside the chemical bath, the flow rate of the chemical agent supply pipelines is controlled, thereby adjusting the pressure inside the chemical bath to be uniform. The pressure control device proposed in this invention can control the liquid pressure at different positions in the chemical bath, thereby maintaining uniform liquid pressure at each position and preventing pressure differences from affecting the quality of the wafers.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor batch processing equipment technology, specifically relating to a semiconductor wafer batch processing cleaning equipment and its chemical bath pressure control device. Background Technology

[0002] Currently, in semiconductor manufacturing processes, the chemical baths typically used are large baths capable of processing 50 12-inch wafers simultaneously. Existing chemical baths, such as... Figure 1-3 As shown, by setting two chemical supply pipelines at the bottom of the chemical bath, and installing multiple nozzles on the supply pipelines for spraying chemical agents, a liquid level sensor is installed in the chemical bath to detect the liquid level of the chemical agent in the chemical bath. However, due to the pressure difference of the chemical agent at different positions along the longitudinal direction in the chemical bath (as shown in the side view), it will cause differences in the etching rate and particles in multiple wafers, thereby affecting the quality of semiconductor wafers. Summary of the Invention

[0003] To address the issue of semiconductor wafer quality being affected by pressure differences in chemical agents, this invention provides a chemical bath pressure control device suitable for batch cleaning equipment of semiconductor wafers. This invention maintains a consistent chemical agent pressure within the chemical bath through this pressure control device, thereby ensuring the quality of the semiconductor wafers.

[0004] This invention is achieved through the following technical solution:

[0005] A chemical bath pressure control device includes n sets of chemical supply pipelines installed at different positions at the bottom of the chemical bath, and n sets of liquid level pressure sensors installed on the upper side of the chemical bath; wherein n is a positive integer greater than or equal to 3;

[0006] Furthermore, the liquid level pressure sensor is installed in a one-to-one correspondence with the chemical agent supply pipeline;

[0007] n sets of liquid level pressure sensors are used to detect the pressure values ​​at different locations inside the chemical bath;

[0008] Based on the pressure values ​​detected at different locations inside the chemical bath, the flow rate of the chemical agent supply pipeline is controlled, thereby adjusting the pressure inside the chemical bath to be uniform.

[0009] Preferably, each group of supply pipelines in this invention consists of a main pipeline and two branch pipelines connected to the main pipeline;

[0010] The main pipeline is located outside the chemical bath, and the two branch pipelines are located inside the chemical bath. The chemical agent flows in through the main pipeline and is sprayed into the chemical bath through the two branch pipelines.

[0011] A hydraulic pump is installed on the main pipeline, and the flow rate of the liquid sprayed in the branch pipeline can be controlled by controlling the speed of the hydraulic pump.

[0012] Preferably, all n sets of liquid level pressure sensors of the present invention are installed on the chemical bath cover.

[0013] Preferably, the device of the present invention includes three sets of supply lines and three sets of pressure sensors;

[0014] Each pressure sensor group includes two pressure sensors symmetrically arranged on the left and right sides of the chemical bath.

[0015] Preferably, the device of the present invention further includes a controller;

[0016] The controller is communicatively connected to n sets of liquid level pressure sensors to acquire and process the detection signals from the n sets of pressure sensors in real time.

[0017] The controller is communicatively connected to the hydraulic pumps on the n sets of chemical supply pipelines, and is used to send control signals to the hydraulic pumps in real time.

[0018] Preferably, the device of the present invention further includes a controller;

[0019] The controller acquires the detection signal from the pressure sensor in real time;

[0020] The controller calculates the measured pressure of each pressure sensor group based on the acquired detection signals:

[0021] The controller sends a corresponding control signal to control the speed of the hydraulic pump based on the calculated measured pressure and pressure threshold, thereby regulating the internal pressure of the chemical bath.

[0022] Preferably, the controller of the present invention compares the measured pressure with a pressure threshold. If the measured pressure is greater than the pressure threshold, a control signal is sent to control the hydraulic pump to reduce its speed; if the measured pressure is less than the pressure threshold, a control signal is sent to control the hydraulic pump to increase its speed; if the measured pressure is equal to the pressure threshold, the hydraulic pump continues to operate at the current speed.

[0023] Secondly, this invention proposes a method for controlling the pressure of a chemical bath, comprising:

[0024] Chemical agents are supplied through multiple sets of chemical agent supply pipelines installed at different locations at the bottom of the chemical bath;

[0025] Multiple sets of liquid level pressure sensors, each corresponding to a set of chemical supply pipelines, are installed at the top of the chemical bath to detect the pressure values ​​at different locations inside the chemical bath.

[0026] Based on the pressure values ​​detected at different locations inside the chemical bath, the flow rate of the chemical agent spraying in the chemical agent supply pipeline is controlled, thereby adjusting the internal pressure of the chemical bath to be uniform.

[0027] Thirdly, the present invention proposes a semiconductor wafer batch cleaning equipment, which uses the chemical bath pressure control device described in the present invention to regulate the internal pressure of the chemical bath.

[0028] The present invention has the following advantages and beneficial effects:

[0029] The pressure control device proposed in this invention can control the liquid pressure at different locations in a chemical bath, thereby maintaining consistent liquid pressure at each location and preventing pressure differences from affecting the quality of the wafers.

[0030] The pressure control device proposed in this invention has a simple structure, is easy to implement, and improves the processing quality of semiconductor wafers. Attached Figure Description

[0031] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0032] Figure 1 This is a schematic diagram of an existing chemical bath structure.

[0033] Figure 2 for Figure 1 The diagram shows a top view of the chemical bath structure.

[0034] Figure 3 for Figure 1 The chemical bath structure shown is a side view.

[0035] Figure 4 This is a schematic diagram of the chemical bath structure of the present invention.

[0036] Figure 5 for Figure 4 The diagram shows a top view of the chemical bath structure.

[0037] Figure 6 for Figure 4 The chemical bath structure shown is a side view.

[0038] The attached diagram shows the markings and corresponding component names:

[0039] 10-Wafer, 11-Supply line, 12-Chemical bath cover, 13-Chemical bath, 14-Level sensor, 15-Sensor mounting bracket, 16-Chemical agent, 21-First supply line, 22-Second supply line, 23-Third supply line, 24-First group of pressure sensors, 25-Second group of pressure sensors, 26-Third group of pressure sensors. Detailed Implementation

[0040] In the following, the terms “comprising” or “may include” as used in various embodiments of the invention indicate the presence of an inventive function, operation, or element, and do not limit the addition of one or more functions, operations, or elements. Furthermore, as used in various embodiments of the invention, the terms “comprising,” “having,” and their cognates are intended only to indicate a specific feature, number, step, operation, element, component, or combination of the foregoing, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations of the foregoing, or adding one or more combinations of the foregoing.

[0041] In various embodiments of the invention, the expression "or" or "at least one of A and / or B" includes any combination or all combinations of the words listed simultaneously. For example, the expression "A or B" or "at least one of A and / or B" may include A, may include B, or may include both A and B.

[0042] The expressions used in the various embodiments of the present invention (such as "first," "second," etc.) may modify various constituent elements in the various embodiments, but do not limit the corresponding constituent elements. For example, the above expressions do not limit the order and / or importance of the elements. The above expressions are only used for the purpose of distinguishing one element from other elements. For example, a first user device and a second user device refer to different user devices, although both are user devices. For example, a first element may be referred to as a second element without departing from the scope of the various embodiments of the present invention, and similarly, a second element may also be referred to as a first element.

[0043] It should be noted that if a description is made of "connecting" one component to another, then the first component can be directly connected to the second component, and a third component can be "connected" between the first and second components. Conversely, when a component is "directly connected" to another component, it can be understood that there is no third component between the first and second components.

[0044] The terminology used in the various embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to limit the various embodiments of the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of the invention pertain. The terms (such as those defined in a generally used dictionary) are to be interpreted as having the same meaning as in the context of the relevant technical field and are not to be interpreted as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of the invention.

[0045] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0046] Example

[0047] This embodiment provides a chemical bath pressure control device suitable for semiconductor wafer batch cleaning equipment. The device in this embodiment detects the pressure difference at different positions in the chemical bath 13 by setting sensors at different positions in the chemical bath 13. Based on the detected pressure data, the speed of the control device (pump) on the chemical agent supply pipeline is controlled, thereby controlling the spray flow rate of the chemical agent supplied on the supply pipeline, so as to control the liquid pressure at different positions in the chemical bath 13 to be controlled at the same pressure value, maintain the internal pressure of the chemical bath 13, and prevent the generation of pressure difference that may cause quality problems of semiconductor wafers.

[0048] The device in this embodiment includes at least three sets of chemical agent supply pipelines arranged at different positions at the bottom of the chemical bath 13 along the length of the chemical bath 13, and at least three sets of liquid level pressure sensors correspondingly arranged on the upper side inside the chemical bath 13, with each liquid level pressure sensor corresponding to a chemical agent supply pipeline.

[0049] like Figure 4-6As shown, this embodiment preferably employs three sets of chemical agent supply pipelines, namely, a first supply pipeline 21, a second supply pipeline 22, and a third supply pipeline 23 arranged sequentially at the bottom of the chemical bath 13 along its length. The first supply pipeline 21, the second supply pipeline 22, and the third supply pipeline 23 have the same structure, each consisting of a main pipeline and two branch pipelines connected to the main pipeline. The main pipeline is located outside the chemical bath 13, and the two branch pipelines are located inside the chemical bath 13. The chemical agent flows in through the main pipeline and is sprayed into the chemical bath 13 through the two branch pipelines. The chemical agent spraying flow rate of the two branch pipelines is controlled by a pump installed on the main pipeline, that is, the first supply pipeline 21 is controlled by pump P1, the second supply pipeline 22 is controlled by pump P2, and the third supply pipeline 23 is controlled by pump P3.

[0050] A set of pressure sensors 24 is installed on the upper side of the chemical bath 13 corresponding to the first supply line 21, a set of pressure sensors 25 is installed corresponding to the second supply line 22, and a set of pressure sensors 26 is installed corresponding to the third supply line 23. Each set of pressure sensors includes two pressure sensors symmetrically arranged on the left and right sides of the chemical bath 13, for a total of 6 pressure sensors, in order to improve the reliability of the detection data.

[0051] The pressure sensor in this embodiment can be installed on the chemical bath cover 12.

[0052] The device in this embodiment also includes a controller (not shown in the figure). The controller is used to acquire multiple sets of pressure sensors in real time, and analyze and process the detection signals of the pressure sensors to issue corresponding control signals to control the rotation speed of hydraulic pumps P1, P2 and P3, so as to maintain the consistency of internal pressure of chemical bath 13.

[0053] This embodiment uses the above-described configuration of 3 groups of 6 pressure sensors as an example for illustration:

[0054] The controller acquires the liquid level pressure signals (x1, x2, x3, x4, x5, x6) in the current chemical bath from the first group of pressure sensors 24 (x1, x2), the second group of pressure sensors 25 (x3, x4), and the third group of pressure sensors 26 (x5, x6);

[0055] The controller processes the acquired pressure signals to obtain the first pressure p1, the second pressure p2, and the third pressure p3, respectively.

[0056] p1=(x1+x2) / 2; p2=(x3+x4) / 2; p3=(x5+x6) / 2;

[0057] The control system compares the first pressure p1, the second pressure p2, and the third pressure p3 with a preset pressure threshold p0, and issues corresponding control signals to control the rotational speeds of pumps P1, P2, and P3 based on the comparison results.

[0058] If the first pressure p1 is greater than the preset pressure p0, the controller sends a control signal to control the pump P1 to reduce its speed; if the first pressure p1 is less than the preset pressure p0, the controller sends a control signal to control the pump P1 to increase its speed; if the first pressure p1 is equal to the preset pressure p0, the controller does not send a control signal, that is, the pump P1 continues to work at the current speed.

[0059] Similarly, if the second pressure p2 is greater than the preset pressure p0, the controller sends a control signal to control the pump P2 to reduce its speed; if the second pressure p2 is less than the preset pressure p0, the controller sends a control signal to control the pump P2 to increase its speed; if the second pressure p2 is equal to the preset pressure p0, the controller does not send a control signal, that is, the pump P2 continues to work at its current speed.

[0060] If the third pressure p3 is greater than the preset pressure p0, the controller sends a control signal to control pump P3 to reduce its speed; if the third pressure p3 is less than the preset pressure p0, the controller sends a control signal to control pump P3 to increase its speed; if the third pressure p3 is equal to the preset pressure p0, the controller does not send a control signal, that is, it keeps pump P3 at its current speed and continues to work.

[0061] In another preferred embodiment, the chemical supply pipeline and liquid level pressure sensor can also be configured as 4 groups, and each group of liquid level pressure sensors can also be configured as 3, etc.

[0062] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A chemical bath pressure control device, characterized by, The n groups of chemical agent supply pipelines are arranged at different positions of the bottom of the chemical bath (13), and the n groups of liquid level pressure sensors are arranged on the upper side of the chemical bath (13); wherein n is a positive integer greater than or equal to 3; The liquid level pressure sensor is arranged in one-to-one correspondence with the chemical agent supply pipeline; The n groups of liquid level pressure sensors are used for detecting pressure values at different positions inside the chemical bath (13); According to the detected pressure values at different positions inside the chemical bath (13), the chemical agent supply flow of the chemical agent supply pipeline is controlled, so that the pressure inside the chemical bath (13) is adjusted to be consistent; Each group of the supply pipeline is composed of a main pipeline and two branch pipelines connected with the main pipeline; The main pipeline is located outside the chemical bath (13), and the two branch pipelines are located inside the chemical bath (13); the chemical agent flows in through the main pipeline and is sprayed into the chemical bath (13) through the two branch pipelines; A hydraulic pump is arranged on the main pipeline, and the rotation speed of the hydraulic pump can be controlled to control the liquid flow of the branch pipeline; Each group of liquid level pressure sensors includes two pressure sensors symmetrically arranged on the left and right sides of the chemical bath (13); A controller is further included; The controller acquires the detection signals of the pressure sensors in real time; The controller calculates the measured pressure of each group of pressure sensors according to the acquired detection signals: The controller sends corresponding control signals to control the rotation speed of the hydraulic pump according to the calculated measured pressure and the pressure threshold, so as to adjust the pressure inside the chemical bath (13); The controller compares the measured pressure with the pressure threshold; if the measured pressure is greater than the pressure threshold, the controller sends a control signal to control the hydraulic pump to reduce the rotation speed; if the measured pressure is less than the pressure threshold, the controller sends a control signal to control the hydraulic pump to increase the rotation speed; if the measured pressure is equal to the pressure threshold, the controller keeps the hydraulic pump working at the current rotation speed.

2. The chemical bath pressure control apparatus of claim 1, wherein The n groups of liquid level pressure sensors are all installed on the chemical bath cover (12).

3. The chemical bath pressure control apparatus of claim 1, wherein Three groups of supply pipelines and three groups of pressure sensors are included.

4. The chemical bath pressure control apparatus of claim 1, wherein A controller is further included; The controller is in communication connection with the n groups of liquid level pressure sensors, is used for acquiring and processing the detection signals of the n groups of pressure sensors in real time; The controller is in communication connection with the hydraulic pumps on the n groups of chemical agent supply pipelines, and is used for sending control signals to the hydraulic pumps in real time.

5. A method of chemical bath pressure control, characterized by, Chemical agents are provided by the multiple groups of chemical agent supply pipelines arranged at different positions of the bottom of the chemical bath (13); The pressure values at different positions inside the chemical bath (13) are detected by the multiple groups of liquid level pressure sensors arranged in one-to-one correspondence with the multiple groups of chemical agent supply pipelines on the upper part of the chemical bath (13); According to the detected pressure values at different positions inside the chemical bath (13), the chemical agent spraying flow of the chemical agent supply pipeline is controlled, so that the pressure inside the chemical bath (13) is adjusted to be consistent; Each group of liquid level pressure sensors includes two pressure sensors symmetrically arranged on the left and right sides of the chemical bath (13); Each group of the supply pipeline is composed of a main pipeline and two branch pipelines connected with the main pipeline; ​ The main pipe is located outside the chemical bath (13), and two branch pipes are located inside the chemical bath (13), and the chemical agent flows in through the main pipe and is sprayed into the chemical bath (13) through the two branch pipes; A hydraulic pump is arranged on the main pipe, and the flow rate of the liquid sprayed by the branch pipes can be controlled by controlling the rotating speed of the hydraulic pump; The detection signal of the pressure sensor is acquired in real time by the controller; The controller calculates the measured pressure of each group of pressure sensors according to the acquired detection signal; The controller sends a corresponding control signal to control the rotating speed of the hydraulic pump according to the calculated measured pressure and the pressure threshold value, so as to adjust the internal pressure of the chemical bath (13); The controller compares the measured pressure with the pressure threshold value, and if the measured pressure is greater than the pressure threshold value, a control signal is sent to control the hydraulic pump to reduce the rotating speed; if the measured pressure is less than the pressure threshold value, a control signal is sent to control the hydraulic pump to increase the rotating speed; and if the measured pressure is equal to the pressure threshold value, the hydraulic pump continues to work at the current rotating speed.

6. A semiconductor wafer batch processing cleaning apparatus characterized by comprising: The chemical bath pressure control device according to any one of claims 1-4 is used to adjust the internal pressure of the chemical bath (13).

Images