Metal pollution detection device for CMP (chemical mechanical polishing) machine and CMP machine

Abstract

The utility model provides a CMP machine table metal pollution detection device and a CMP machine table, and the CMP machine table metal pollution detection device comprises a metal element detector which is connected with a liquid discharge pipe of the CMP machine table and is used for detecting the concentration of metal elements in liquid discharged by the CMP machine table. When the liquid discharge pipe discharges liquid, the metal element detector detects the concentration of metal elements in the discharged liquid of the CMP machine table, and the actual concentration of each metal element is compared with the corresponding concentration threshold value to obtain a detection result, namely whether metal pollution exists or not; therefore, the metal pollution condition in the discharged liquid can be found in time and measures can be taken, so that the reduction of the product quality of follow-up running wafers caused by metal pollution is avoided, the generation of unqualified products is reduced, and the yield of products is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor manufacturing, in particular to a CMP machine metal contamination detection device and a CMP machine. Background Art

[0002] In the semiconductor manufacturing process, metal contamination of the wafer will have an adverse effect on the performance of the components of the product. For example, heavy metals such as iron and nickel diffuse into the silicon wafer, causing leakage current in the PN structure of the component, thereby affecting the performance and life of the component. Therefore, in order to monitor the degree of metal contamination during the process, a real-time monitoring and high-reliability monitoring method is sought.

[0003] Wafer chemical mechanical polishing (CMP) is a combination of chemical corrosion and mechanical friction. The wafer is fixed on a grinding head facing downward. The rotating table below the wafer is covered with a grinding pad. The grinding slurry with small abrasive particles flows onto the table. The material on the wafer surface is eroded by the abrasive particles and is ground away little by little, and then washed away by the grinding slurry. The surface of the wafer is ground through the relative rotation of the grinding head and the rotating table, and the combined action of the abrasive slurry, thereby achieving the purpose of polishing or flattening.

[0004] Metal contamination caused by the CMP process is mainly due to contact with the pollution source (the carrier, base, polishing liquid and container in the machine, etc.), which causes the metal impurities from the pollution source to adhere to the semiconductor chip. Currently, the chemical mechanical polishing machines in the semiconductor industry lack a monitoring mechanism for metal contamination. If metal contamination is not detected in time, it will affect the quality of the finished products of subsequent wafers and reduce the product yield.

[0005] In view of this, it is necessary to propose a CMP machine metal contamination detection device and a CMP machine to solve the above problems. Utility Model Content

[0006] The utility model aims to provide a CMP machine metal contamination detection device and a CMP machine, so as to improve the problem that the existing chemical mechanical polishing machine lacks a monitoring mechanism for metal contamination.

[0007] The utility model provides a CMP machine metal pollution detection device, comprising: a metal element detector installed and connected with a discharge pipe of the CMP machine, and used for detecting the concentration of metal elements in the discharge liquid of the CMP machine.

[0008] In a possible embodiment, the metal element detector includes a sampling component installed on the liquid discharge pipe and a detection component for detecting the sample liquid of the sampling component;

[0009] The detection component can be a colorimetric sensor, an electrochemical sensor, a fluorescence spectrometer or an atomic absorption spectrometer.

[0010] In a possible embodiment, the metal contamination detection device further includes a controller connected to the detection component.

[0011] In a possible embodiment, the metal contamination detection device further includes an alarm connected to the controller, and when metal contamination is detected, the controller controls the alarm to issue an alarm message.

[0012] In a possible embodiment, when the detection component is the colorimetric sensor or the electrochemical sensor,

[0013] The sampling component is a liquid sampler installed on the liquid discharge pipe, and the detection component is arranged in a sampling bottle of the liquid sampler; or,

[0014] The sampling assembly includes a sampling tube, a liquid inlet valve and a detection box. One end of the sampling tube is connected to the liquid discharge tube and the other end is connected to the detection box. The liquid inlet valve is installed on the sampling tube, and the detection assembly is arranged in the detection box.

[0015] In a possible embodiment, when the sampling component is the liquid sampler, a conduit is provided at the bottom of the sampling bottle, and a drain valve is provided on the conduit.

[0016] In a possible embodiment, when the sampling assembly includes the detection box, a liquid outlet pipe is provided at the bottom of the detection box, and a liquid outlet valve is provided on the liquid outlet pipe.

[0017] In a possible embodiment, when the detection component is the fluorescence spectrometer, the sampling component includes a liquid collection tube and a control valve installed on the liquid collection tube, one end of the liquid collection tube is connected to the liquid discharge tube, and when sampling, the other end of the liquid discharge tube is extended into the liquid container of the fluorescence spectrometer to transport the sampling liquid.

[0018] In a possible embodiment, when the detection component is the atomic absorption spectrometer, the sampling component includes a delivery tube and a first valve installed on the delivery tube, one end of the delivery tube is connected to the drain pipe and the other end is connected to the liquid storage bottle of the atomic absorption spectrometer.

[0019] The utility model also provides a CMP machine, comprising: a CMP machine metal contamination detection device as in any of the above embodiments.

[0020] The beneficial effect of the CMP machine metal contamination detection device provided by the utility model is that by setting a metal element detector, the concentration of metal elements in the CMP machine discharge liquid is detected when the discharge pipe is draining, so that the metal contamination in the discharge liquid can be discovered in time to avoid affecting the quality of the finished product of the subsequent wafers, thereby improving the yield of the product. In a further scheme, the sample liquid is extracted from the discharge pipe by a detection component, and the sample liquid is detected by the detection component such as a colorimetric sensor, an electrochemical sensor, a fluorescence spectrometer or an atomic absorption spectrometer, thereby improving the accuracy and efficiency of the detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the CMP machine metal contamination detection device of the present invention when a colorimetric sensor is used.

[0022] Figure 2 It is a schematic diagram of the CMP machine metal contamination detection device of the present invention when an electrochemical sensor is used.

[0023] Figure 3 It is a schematic diagram of the CMP machine metal contamination detection device of the present invention when using a fluorescence spectrometer.

[0024] Figure 4 It is a schematic diagram of the CMP machine metal contamination detection device of the present invention when using an atomic absorption spectrometer.

[0025] Explanation of the reference numerals: CMP machine 100; drain pipe 110; metal contamination detection device 200; sampling assembly 210; liquid sampler 211; sampling bottle 2111; switch valve 2112; catheter 2113; drain valve 2114; sampling tube 2121; liquid inlet valve 2122; detection box 2123; liquid outlet pipe 2124; liquid outlet valve 2125; liquid collection pipe 2131; control valve 2132; delivery pipe 2141; first valve 2142; output pipe 2143; second valve 2144; colorimetric sensor 310; electrochemical sensor 320; fluorescence spectrometer 330; liquid container 331; atomic absorption spectrometer 340; liquid bottle 341. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the utility model clearer, the technical solution in the embodiments of the utility model will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] In view of the problems existing in the prior art, the embodiment of the utility model provides a CMP machine metal contamination detection device. Figure 1 This is a schematic diagram of the CMP machine metal contamination detection device of the present invention when a colorimetric sensor is used, see Figure 1 The metal contamination detection device 200 includes: a metal element detector installed and connected to the discharge pipe 110 of the CMP machine 100, and used to detect the concentration of metal elements in the discharge liquid of the CMP machine 100.

[0028] The CMP machine metal contamination detection device in this embodiment proposes a metal contamination monitoring mechanism. When the drain pipe 110 is discharging liquid, the metal element detector detects the concentration of metal elements in the discharge liquid of the CMP machine 100, and compares the actual concentration of each metal element with its corresponding concentration threshold to obtain a detection result, that is, whether there is metal contamination, to help operators promptly detect metal contamination in the discharge liquid, avoid the subsequent product quality decline of wafers due to metal contamination, reduce the generation of defective products, and improve the product yield.

[0029] In a possible embodiment, the metal element detector includes a sampling assembly 210 installed on the drain pipe 110 and a detection assembly for detecting the sampled liquid of the sampling assembly 210. The detection assembly can be a colorimetric sensor 310, an electrochemical sensor 320, a fluorescence spectrometer 330, or an atomic absorption spectrometer 340, etc. In this embodiment, when the drain pipe 110 is draining liquid, the sampling liquid can be extracted from the drained liquid through the sampling assembly 210 arranged on the drain pipe 110, and then the sampling liquid is detected by a professional detection element, thereby improving the accuracy and efficiency of metal element detection.

[0030] The first colorimetric sensing detection method uses a colorimetric sensor 310. During detection, the light source of the colorimetric sensor 310 emits a light beam of a specific wavelength to the sample liquid, which is partially absorbed by the metal elements in the sample liquid. The photosensitive element of the colorimetric sensor 310 receives the reflected light beam of the sample liquid and converts it into an electrical signal. The colorimetric sensing detection method has a fast response, low cost, high accuracy, and detects more ions, but its stability is relatively poor.

[0031] The second electrochemical method uses an electrochemical sensor 320 to detect the concentration of metal ions by measuring the current or potential change generated by the redox reaction of metal ions in the sample solution on the electrode. Different metal ions have different redox potentials. The electrochemical detection method has a rapid response, low cost, high sensitivity, and is suitable for on-site detection, but its equipment cost is relatively high.

[0032] The third fluorescence method uses a fluorescence spectrometer 330. Certain metal ions can react with specific fluorescent reagents to generate substances with fluorescent properties. The fluorescence spectrometer 330 can determine the type and concentration of metal ions by exciting these substances and measuring the fluorescence spectrum emitted by them. The fluorescence method has the characteristics of high sensitivity and high selectivity, and is particularly suitable for the detection of low-concentration metal ions.

[0033] The fourth type of atomic absorption spectrometry uses an atomic absorption spectrometer 340. The sample solution is converted into an atomic state in the atomic absorption spectrometer 340. When light of a specific wavelength passes through the atomic state sample solution, the metal atoms absorb part of the light energy. By measuring the degree of light absorption, the concentration of the metal ions can be determined. The atomic absorption spectrometry has the advantages of high precision and high resolution, and is suitable for the simultaneous detection of multiple metal ions.

[0034] In a preferred embodiment, the metal contamination detection device 200 also includes a controller (not shown) connected to the detection component. In the actual detection process, the controller can detect different metal ion components under different processes by controlling the working parameters of the colorimetric sensor 310 or the electrochemical sensor 320, such as light source intensity, wavelength selection, electrode potential, etc. For the colorimetric sensor 310, the controller can adjust the light source to emit light of a specific wavelength; for the electrochemical sensor 320, the controller can accurately control the potential of the electrode. The controller receives the detection signal of the detection component and obtains the detection result after processing and analysis.

[0035] In another embodiment, the metal contamination detection device 200 further includes an alarm (not shown) connected to the controller. When metal contamination is detected, the controller controls the alarm to issue an alarm message. In this embodiment, when the detection result is that metal contamination exists, the controller controls the alarm to issue an alarm message, and can notify the operator at the first time. This instant feedback mechanism can avoid serious quality accidents and economic losses caused by running away.

[0036] In some embodiments, Figure 1 This is a schematic diagram of the CMP machine metal contamination detection device of the present invention when a colorimetric sensor is used. Figure 2 This is a schematic diagram of the CMP machine metal contamination detection device of the utility model when using an electrochemical sensor, see Figure 1 and Figure 2When the detection component is a colorimetric sensor 310 or an electrochemical sensor 320, the sampling component 210 is a liquid sampler 211 installed on the discharge pipe 110, and the detection component is arranged in a sampling bottle 2111 of the liquid sampler 211; or, the sampling component 210 includes a sampling tube 2121, a liquid inlet valve 2122 and a detection box 2123, one end of the sampling tube 2121 is connected to the discharge pipe 110 and the other end is connected to the detection box 2123, the liquid inlet valve 2122 is installed on the sampling tube 2121, and the detection component is arranged in the detection box 2123.

[0037] In a specific embodiment, see Figure 1 When the sampling assembly 210 is a liquid sampler 211, a conduit 2113 is provided at the bottom of the sampling bottle 2111, and a drain valve 2114 is provided on the conduit 2113. Specifically, the controller is connected to the switch valve 2112 of the liquid sampler 211 and the drain valve 2114 on the conduit 2113. When extracting the sampled liquid, the controller controls the switch valve 2112 to open and the drain valve 2114 to close, and extracts the sampled liquid from the drain pipe 110. After sampling, the controller controls the switch valve 2112 to close and performs a concentration test of the metal element. After the current test is completed, the controller controls the drain valve 2114 to open and discharge the sampled liquid. In this embodiment, the controller can accurately control the opening and closing of the switch valve 2112 and the drain valve 2114, thereby realizing automatic control of the sampling and draining process, reducing cumbersome manual operations and improving sampling efficiency.

[0038] In a specific embodiment, see Figure 2 When the sampling assembly 210 includes a detection box 2123, a liquid outlet pipe 2124 is provided at the bottom of the detection box 2123, and a liquid outlet valve 2125 is provided on the liquid outlet pipe 2124. Specifically, the controller is connected to the liquid inlet valve 2122 and the liquid outlet valve 2125. When extracting the sampled liquid, the controller controls the liquid inlet valve 2122 to open and the liquid outlet valve 2125 to close, and extracts the sampled liquid from the liquid discharge pipe 110. After sampling, the controller controls the liquid inlet valve 2122 to close, and performs a concentration test of the metal element. After the current test is completed, the controller controls the liquid outlet valve 2125 to open and discharge the sampled liquid. In this embodiment, the controller accurately controls the entire sampling, testing, and liquid discharge process, thereby realizing an automated and continuous testing process, improving the working efficiency of the metal pollution detection device 200, eliminating the need for manual operation, avoiding errors and pollution that may be caused by manual sampling, and improving the accuracy of the test.

[0039] In one embodiment, Figure 3 This is a schematic diagram of the CMP machine metal contamination detection device of the present invention when using a fluorescence spectrometer, see Figure 3When the detection component is a fluorescence spectrometer 330, the sampling component 210 includes a liquid collection tube 2131 and a control valve 2132 installed on the liquid collection tube 2131. One end of the liquid collection tube 2131 is connected to the liquid discharge tube 110. When sampling, the other end of the liquid discharge tube 110 is extended into the liquid container 331 of the fluorescence spectrometer 330 to transport the sampled liquid. Preferably, the liquid collection tube 2131 is a hose for easy movement. The controller is connected to the control valve 2132 to control the opening and closing of the control valve 2132 to extract the sampled liquid from the liquid discharge tube 110 and introduce it into the liquid container 331.

[0040] In another embodiment, Figure 4 This is a schematic diagram of the CMP machine metal contamination detection device of the present invention when using an atomic absorption spectrometer, see Figure 4 When the detection component is an atomic absorption spectrometer 340, the sampling component 210 includes a delivery tube 2141 and a first valve 2142 installed on the delivery tube 2141. One end of the delivery tube 2141 is connected to the discharge tube 110 and the other end is connected to the liquid storage bottle 341 of the atomic absorption spectrometer 340.

[0041] In one possible embodiment, see Figure 4 When the detection component is an atomic absorption spectrometer 340, the sampling component 210 also includes an output pipe 2143 disposed at the bottom of the liquid bottle 341, and a second valve 2144 is disposed on the output pipe 2143. Specifically, the controller is connected to the first valve 2142 and the second valve 2144. When extracting the sampled liquid, the controller controls the first valve 2142 to open and the second valve 2144 to close, and extracts the sampled liquid from the discharge pipe 110. After sampling, the controller controls the first valve 2142 to close, and performs a concentration test of the metal element. After the current test is completed, the controller controls the second valve 2144 to open and discharge the sampled liquid. In this embodiment, the delivery pipe 2141 is directly connected to the liquid bottle 341 of the atomic absorption spectrometer 340, ensuring that the sampled liquid can directly and efficiently enter the atomic absorption spectrometer 340 for testing, avoiding contamination and errors in the intermediate links. The controller controls the opening and closing of the first valve 2142 to realize automated sampling. After the detection is completed, the controller controls the opening of the second valve 2144 so that the sample liquid can be smoothly discharged from the output pipe 2143, avoiding the tedious process of manual sampling and discharge. There is no need for tedious manual operations, and automated control improves operational efficiency.

[0042] The present invention further provides a CMP machine 100 , comprising: a CMP machine metal contamination detection device 200 as in any of the above embodiments.

[0043] The technical effect of the CMP machine metal contamination detection device of the present invention is explained in detail below in combination with the prior art.

[0044] When the metal components and wafers in contact with the wafer inside the chemical mechanical grinding machine are washed with ultrapure water during the grinding process, if there is metal contamination on the metal components or the surface of the wafer, part of the metal contamination will be washed down by ultrapure water and discharged through the drain pipe 110. The metal contamination detection device 200 of this embodiment directly extracts the sampling liquid from the drain pipe 110 through the matching design of the sampling component 210 and the detection component, and detects the concentration of metal elements in the sampling liquid through the detection component. If the detection result is abnormal, it means that there may be an abnormal point in the machine. The controller controls the alarm to send an alarm message to remind the operator to stop the machine for inspection. In addition, different metal ion components can be selected and monitored according to different processes. For example, common metal elements such as Fe, Al, and Na can be determined according to the drain pipe 110 when the detection result is abnormal and the corresponding action can be taken, which can avoid running goods all the time and causing serious quality accidents and economic losses. The opening and closing of the relevant valves are controlled by the controller to realize automatic and continuous sampling, detection and drainage, thereby improving the detection efficiency and accuracy of detection.

[0045] Although the embodiments of the utility model are described in detail above, it is obvious to those skilled in the art that various modifications and changes can be made to these embodiments. However, it should be understood that such modifications and changes are within the scope and spirit of the utility model described in the claims. Moreover, the utility model described herein may have other embodiments and may be implemented or realized in a variety of ways. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with ordinary skills in the field to which the utility model belongs. The words "including" and the like used herein mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

Claims

1. A CMP machine metal contamination detection device, characterized in that: include: A metal element detector installed and connected to the discharge pipe of the CMP machine is used to detect the concentration of metal elements in the discharge liquid of the CMP machine. The metal element detector includes a sampling component installed on the discharge pipe and a detection component for detecting the sampling liquid of the sampling component. The detection component can be a colorimetric sensor, an electrochemical sensor, a fluorescence spectrometer or an atomic absorption spectrometer.

2. The CMP machine metal contamination detection device according to claim 1, characterized in that: Also included is a controller connected to the detection component.

3. The CMP machine metal contamination detection device according to claim 2, characterized in that: It also includes an alarm connected to the controller. When metal contamination is detected, the controller controls the alarm to send out an alarm message.

4. The CMP machine metal contamination detection device according to claim 1, characterized in that: When the detection component is the colorimetric sensor or the electrochemical sensor, The sampling component is a liquid sampler installed on the liquid discharge pipe, and the detection component is arranged in a sampling bottle of the liquid sampler; or, The sampling assembly includes a sampling tube, a liquid inlet valve and a detection box. One end of the sampling tube is connected to the liquid discharge tube and the other end is connected to the detection box. The liquid inlet valve is installed on the sampling tube, and the detection assembly is arranged in the detection box.

5. The CMP machine metal contamination detection device according to claim 4, characterized in that: When the sampling component is the liquid sampler, a conduit is provided at the bottom of the sampling bottle, and a liquid discharge valve is provided on the conduit.

6. The CMP machine metal contamination detection device according to claim 4, characterized in that: When the sampling assembly includes the detection box, a liquid outlet pipe is provided at the bottom of the detection box, and a liquid outlet valve is provided on the liquid outlet pipe.

7. The CMP machine metal contamination detection device according to claim 1, characterized in that: When the detection component is the fluorescence spectrometer, the sampling component includes a liquid collection tube and a control valve installed on the liquid collection tube. One end of the liquid collection tube is connected to the liquid discharge tube. When sampling, the other end of the liquid discharge tube is extended into the liquid container of the fluorescence spectrometer to transport the sampling liquid.

8. The CMP machine metal contamination detection device according to claim 1, characterized in that: When the detection component is the atomic absorption spectrometer, the sampling component includes a delivery pipe and a first valve installed on the delivery pipe, one end of the delivery pipe is connected to the discharge pipe and the other end is connected to the liquid storage bottle of the atomic absorption spectrometer.

9. A CMP machine, characterized in that: include: A CMP machine metal contamination detection device as described in any one of claims 1 to 8.

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