Positioning disc for four-probe resistivity meter convenient for measuring radial resistivity change of wafer

Abstract

The utility model relates to the technical field of wafer processing equipment, in particular to a positioning disc for a four-probe resistivity meter, which is convenient for measuring the radial resistivity change of a wafer, and comprises a base, a positioning disc is arranged on an upper cover of the base, a plurality of detection positioning areas are arranged on the positioning disc, and a positioning pin is arranged at the edge of each detection positioning area. The detection positioning area comprises four silicon wafer center resistivity test positioning areas which are concentrically arranged. According to the positioning disc for the four-probe resistivity meter convenient for measuring the radial resistivity change of the wafer, accurate positioning and rapid adjustment of the wafer in the measurement process are realized through unique design and an innovative structure. The positioning disc is provided with a detection positioning area which comprises a silicon wafer center resistivity test positioning area and a silicon wafer edge 6mm resistivity test positioning area, so that measurement points can cover key positions of the center and the edge of the wafer, and the radial resistivity uniformity of the wafer is comprehensively evaluated.

Description

Technical Field

[0001] The utility model relates to the technical field of wafer processing equipment, in particular to a positioning plate for a four-probe resistivity instrument which is convenient for measuring radial resistivity changes of wafers. Background Art

[0002] In the semiconductor industry, wafers are core materials, and their quality has a decisive influence on the performance and yield of the final device. Resistivity is one of the key physical parameters of the wafer, which directly affects the electrical performance of semiconductor devices. With the continuous advancement of power device technology and the increasing market demand for high-performance and high-reliability products, the radial uniformity of wafer resistivity has become the focus of manufacturers and researchers.

[0003] Traditional wafer resistivity measurement methods often only focus on the resistivity value at the center or a specific location of the wafer, while ignoring the change in resistivity in the radial direction of the wafer. However, in the actual production process, due to factors such as crystal growth characteristics and the uneven distribution of impurities at the solid-liquid interface during growth, the resistivity of the wafer often shows a non-uniform distribution phenomenon with low resistivity at the center and high resistivity at the edge. This non-uniformity not only affects the local electrical properties of the device, but may also lead to inconsistency in device parameters, thereby reducing the yield and reliability of the product.

[0004] In order to more accurately evaluate the quality of wafers and meet increasingly stringent market requirements, many improved measurement methods and technologies have emerged in recent years. Among them, the four-probe resistivity meter is a widely used measurement tool that can provide relatively accurate resistivity values. However, when using the four-probe resistivity meter for measurement, how to ensure the precise positioning of the wafer and how to perform fast and accurate measurements at different locations remain a problem that needs to be solved. Utility Model Content

[0005] The purpose of the utility model is to provide a positioning plate for a four-probe resistivity meter that is convenient for measuring the radial resistivity change of a chip, so as to solve the problem proposed in the above background technology that when using a four-probe resistivity meter for measurement, how to ensure the precise positioning of the chip and how to perform fast and accurate measurements at different positions are still urgent problems to be solved.

[0006] To achieve the above-mentioned purpose, the utility model provides a positioning plate for a four-probe resistivity meter that is convenient for measuring the radial resistivity change of a wafer, including a base, a positioning plate is installed on the upper cover of the base, a plurality of detection positioning areas are arranged on the positioning plate, a positioning pin is installed at the edge of each detection positioning area, the detection positioning area includes four concentrically arranged silicon wafer center resistivity test positioning areas, and also includes four silicon wafer edge 6mm resistivity test positioning areas arranged at the same edge position, a positioning hole is arranged on the top surface of the positioning plate near the positioning pin, and the bottom of the positioning pin is stuck in the positioning hole.

[0007] Preferably, a foot pad is installed at the bottom of the base.

[0008] Preferably, the silicon wafer center resistivity test positioning area includes a first silicon wafer center resistivity test positioning area, a second silicon wafer center resistivity test positioning area, a third silicon wafer center resistivity test positioning area, and a fourth silicon wafer center resistivity test positioning area.

[0009] Preferably, the diameter of the first silicon wafer central resistivity test positioning area is 3 inches, the diameter of the second silicon wafer central resistivity test positioning area is 4 inches, the diameter of the third silicon wafer central resistivity test positioning area is 5 inches, and the size of the fourth silicon wafer central resistivity test positioning area is 6 inches.

[0010] Preferably, the 6mm resistivity test positioning area at the edge of the silicon wafer includes a first 6mm resistivity test positioning area at the edge of the silicon wafer, a second 6mm resistivity test positioning area at the edge of the silicon wafer, a third 6mm resistivity test positioning area at the edge of the silicon wafer, and a fourth 6mm resistivity test positioning area at the edge of the silicon wafer.

[0011] Preferably, the diameter of the 6mm resistivity test positioning area at the edge of the first silicon wafer is 3 inches, the diameter of the 6mm resistivity test positioning area at the edge of the second silicon wafer is 4 inches, the diameter of the 6mm resistivity test positioning area at the edge of the third silicon wafer is 5 inches, and the diameter of the 6mm resistivity test positioning area at the edge of the fourth silicon wafer is 6 inches.

[0012] Preferably, the positioning pin comprises a threaded column, the external thread of the threaded column is connected to a threaded sleeve, and the external sleeve of the threaded sleeve is provided with a protective sleeve made of rubber material.

[0013] Preferably, a positioning block is installed at the bottom of the threaded column, and the positioning block is snap-fitted with the positioning hole at the top of the positioning plate. A slot is provided at the top of the base, and a block is installed at the bottom of the positioning plate, and the slot is snap-fitted with the block.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] The positioning plate for the four-probe resistivity meter, which is convenient for measuring the radial resistivity change of the wafer, realizes the precise positioning and rapid adjustment of the wafer during the measurement process through unique design and innovative structure. The positioning plate is provided with a detection positioning area, including a resistivity test positioning area at the center of the silicon wafer and a 6mm resistivity test positioning area at the edge of the silicon wafer, so that the measurement points can cover the key positions of the center and edge of the wafer, thereby comprehensively evaluating the radial uniformity of the resistivity of the wafer. The design of the positioning pin enables the wafer to be quickly and accurately moved and positioned on the positioning plate, avoiding position deviation during the measurement process and improving the accuracy and repeatability of the measurement. At the same time, the positioning block at the bottom of the positioning pin is engaged with the positioning hole at the top of the positioning plate, ensuring the precise installation and convenient disassembly of the positioning pin, which is convenient for the user to quickly adjust the measurement position of wafers of different sizes.

[0016] In addition, the positioning plate also takes into account the convenience and comfort of use. The matching design of the threaded column and the threaded sleeve allows the height of the positioning pin to be adjusted as needed to adapt to wafers or crystal blocks of different thicknesses. The setting of the protective sleeve can protect the positioning pin and the wafer to avoid damage caused by movement and contact during the measurement process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0018] Figure 2 This is one of the structural schematic diagrams of the positioning plate in the utility model;

[0019] Figure 3 This is the second structural schematic diagram of the positioning plate in the utility model;

[0020] Figure 4 It is a structural schematic diagram of the positioning pin in the utility model.

[0021] The meaning of each number in the figure is:

[0022] 1. Base; 11. Foot pad; 12. Card slot; 2. Positioning plate; 21. First silicon wafer center resistivity test positioning area; 22. Second silicon wafer center resistivity test positioning area; 23. Third silicon wafer center resistivity test positioning area; 24. Fourth silicon wafer center resistivity test positioning area; 25. First silicon wafer edge 6mm resistivity test positioning area; 26. Second silicon wafer edge 6mm resistivity test positioning area; 27. Third silicon wafer edge 6mm resistivity test positioning area; 28. Fourth silicon wafer edge 6mm resistivity test positioning area; 29. ​​Card block; 3. Positioning pin; 31. Threaded column; 311. Positioning block; 32. Threaded sleeve; 33. Protective sleeve. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in 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.

[0024] The utility model provides a positioning plate for a four-probe resistivity instrument which is convenient for measuring the radial resistivity change of a wafer. Figure 1-Figure 4 As shown, it includes a base 1, a positioning plate 2 is installed on the upper cover of the base 1, a plurality of detection positioning areas are arranged on the positioning plate 2, a positioning pin 3 is installed at the edge of each detection positioning area, the detection positioning area includes four concentrically arranged silicon wafer center resistivity test positioning areas, and also includes four silicon wafer edge 6mm resistivity test positioning areas arranged at the same edge position, a positioning hole is arranged on the top surface of the positioning plate 2 near the positioning pin 3, and the bottom of the positioning pin 3 is stuck in the positioning hole.

[0025] In this embodiment, a foot pad 11 is installed at the bottom of the base 1 to facilitate the support of the base 1.

[0026] Specifically, the silicon wafer center resistivity test positioning area includes a first silicon wafer center resistivity test positioning area 21 , a second silicon wafer center resistivity test positioning area 22 , a third silicon wafer center resistivity test positioning area 23 , and a fourth silicon wafer center resistivity test positioning area 24 .

[0027] Furthermore, the diameter of the first silicon wafer center resistivity test positioning area 21 is 3 inches, the diameter of the second silicon wafer center resistivity test positioning area 22 is 4 inches, the diameter of the third silicon wafer center resistivity test positioning area 23 is 5 inches, and the size of the fourth silicon wafer center resistivity test positioning area 24 is 6 inches.

[0028] Furthermore, the 6mm resistivity test positioning area at the edge of the silicon wafer includes a first 6mm resistivity test positioning area 25, a second 6mm resistivity test positioning area 26, a third 6mm resistivity test positioning area 27, and a fourth 6mm resistivity test positioning area 28.

[0029] Furthermore, the diameter of the 6mm resistivity test positioning area 25 at the edge of the first silicon wafer is 3 inches, the diameter of the 6mm resistivity test positioning area 26 at the edge of the second silicon wafer is 4 inches, the diameter of the 6mm resistivity test positioning area 27 at the edge of the third silicon wafer is 5 inches, and the diameter of the 6mm resistivity test positioning area 28 at the edge of the fourth silicon wafer is 6 inches.

[0030] Furthermore, the positioning pin 3 includes a threaded column 31, the external thread of the threaded column 31 is connected to a threaded sleeve 32, and the external sleeve of the threaded sleeve 32 is provided with a protective sleeve 33 made of rubber material to improve the protection effect and avoid chip damage.

[0031] Furthermore, a positioning block 311 is installed at the bottom of the threaded column 31, and the positioning block 311 is snap-fitted with the positioning hole at the top of the positioning plate 2. A slot 12 is provided at the top of the base 1, and a block 29 is installed at the bottom of the positioning plate 2. The slot 12 is snap-fitted with the block 29 to facilitate the placement of the positioning plate 2.

[0032] It is worth noting that the radial uniformity of the resistivity of the wafer is usually measured by the radial resistivity variation (RRV), which refers to the difference between the resistivity of the wafer center point and a certain point deviating from the wafer center or several symmetrically distributed setting points (typical setting points are 1 / 2 of the wafer radius or near the edge of the wafer). This resistivity difference can be expressed as the measured difference divided by the center value, expressed as a percentage. Most customers' requirements for wafer RRV are based on the edge 6mm setting point, so the measurement points of wafer RRV include the center point and the edge 6mm point.

[0033] When the utility model is used, the positioning plate for the four-probe resistivity meter for measuring the radial resistivity change of the wafer is first placed on the corresponding detection positioning area. These positioning areas are composed of four concentrically arranged silicon wafer center resistivity test positioning areas and four silicon wafer edge 6mm resistivity test positioning areas arranged at the same edge positions, ensuring that the resistivity of the center point and the edge 6mm point of the wafer can be effectively measured. Positioning areas of different sizes are used for placing wafers of different sizes. The function of the positioning pin 3 is to fix the wafer on the positioning plate 2, so that it can be quickly moved and accurately positioned when measuring the center and edge, thereby ensuring the accuracy of the measurement.

[0034] The bottom of the positioning pin 3 is engaged with the positioning hole on the top of the positioning plate through the positioning block 311, so as to realize the precise positioning of the wafer. At the same time, the design of the positioning pin 3 also takes into account the flexibility of adjustment, and its height can be adjusted as needed to adapt to wafers or crystal blocks of different thicknesses. The matching design of the threaded column 31 and the threaded sleeve 32 makes the adjustment of the positioning pin 3 simple and quick, greatly improving the efficiency of measurement.

[0035] After the wafer is placed, the four-probe resistivity meter can be used for measurement. During measurement, the probes of the four-probe resistivity meter contact the measurement points on the wafer respectively, and the resistivity of the wafer is calculated by measuring the changes in current and voltage. Due to the precise design of the positioning plate and the firm fixation of the positioning pins, the probes can accurately contact the measurement points, thereby ensuring the accuracy of the measurement results.

[0036] After the measurement is completed, multiple measurements can be performed on the wafer at different locations as needed to obtain more comprehensive radial resistivity uniformity data. This data is crucial for evaluating the quality and performance of the wafer, and can help manufacturers identify problems in a timely manner and take appropriate measures to improve them.

[0037] In general, the positioning plate achieves fast and accurate measurement of radial uniformity of wafer resistivity through precise design and flexible adjustment function. It not only improves the efficiency and accuracy of measurement, but also provides a reliable and practical solution for wafer quality control in the semiconductor industry.

[0038] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the utility model and are not used to limit the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A positioning plate for a four-probe resistivity meter for measuring radial resistivity variation of a wafer, comprising a base (1), characterized in that: The upper cover of the base (1) is provided with a positioning plate (2), and a plurality of detection positioning areas are arranged on the positioning plate (2). A positioning pin (3) is installed at the edge of each detection positioning area. The detection positioning area includes four concentrically arranged silicon wafer center resistivity test positioning areas, and also includes four silicon wafer edge 6mm resistivity test positioning areas arranged at the same edge position. A positioning hole is arranged on the top surface of the positioning plate (2) near the positioning pin (3), and the bottom of the positioning pin (3) is stuck in the positioning hole.

2. The positioning plate for a four-probe resistivity meter for measuring radial resistivity variation of a wafer according to claim 1, characterized in that: A foot pad (11) is installed at the bottom of the base (1).

3. The positioning plate for a four-probe resistivity meter for measuring radial resistivity variation of a wafer according to claim 1, characterized in that: The silicon wafer center resistivity test positioning area comprises a first silicon wafer center resistivity test positioning area (21), a second silicon wafer center resistivity test positioning area (22), a third silicon wafer center resistivity test positioning area (23), and a fourth silicon wafer center resistivity test positioning area (24).

4. The positioning plate for a four-probe resistivity meter for measuring radial resistivity variation of a wafer according to claim 3, characterized in that: The diameter of the first silicon wafer central resistivity test positioning area (21) is 3 inches, the diameter of the second silicon wafer central resistivity test positioning area (22) is 4 inches, the diameter of the third silicon wafer central resistivity test positioning area (23) is 5 inches, and the size of the fourth silicon wafer central resistivity test positioning area (24) is 6 inches.

5. The positioning plate for a four-probe resistivity meter for measuring radial resistivity variation of a wafer according to claim 1, characterized in that: The 6mm resistivity test positioning area at the edge of the silicon wafer comprises a first 6mm resistivity test positioning area (25) at the edge of the silicon wafer, a second 6mm resistivity test positioning area (26) at the edge of the silicon wafer, a third 6mm resistivity test positioning area (27) at the edge of the silicon wafer, and a fourth 6mm resistivity test positioning area (28) at the edge of the silicon wafer.

6. The positioning plate for a four-probe resistivity meter for measuring radial resistivity variation of a wafer according to claim 5, characterized in that: The diameter of the 6mm resistivity test positioning area (25) at the edge of the first silicon wafer is 3 inches, the diameter of the 6mm resistivity test positioning area (26) at the edge of the second silicon wafer is 4 inches, the diameter of the 6mm resistivity test positioning area (27) at the edge of the third silicon wafer is 5 inches, and the diameter of the 6mm resistivity test positioning area (28) at the edge of the fourth silicon wafer is 6 inches.

7. The positioning plate for a four-probe resistivity meter for measuring radial resistivity variation of a wafer according to claim 1, characterized in that: The positioning pin (3) comprises a threaded column (31), the external thread of the threaded column (31) is connected to a threaded sleeve (32), and the external sleeve of the threaded sleeve (32) is provided with a protective sleeve (33) made of rubber material.

8. The positioning plate for a four-probe resistivity meter for measuring radial resistivity variation of a wafer according to claim 7, characterized in that: A positioning block (311) is installed at the bottom of the threaded column (31), and the positioning block (311) is snap-fitted with a positioning hole at the top of the positioning plate (2). A snap-fitting groove (12) is provided at the top of the base (1), and a snap-fitting block (29) is installed at the bottom of the positioning plate (2), and the snap-fitting groove (12) is snap-fitted with the snap-fitting block (29).

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