A non-contact wafer size measurement device

Abstract

This utility model relates to the field of wafer size measurement technology, specifically a non-contact wafer size measurement device, including a frame. A two-dimensional motion platform is mounted on the top of the frame, and a wafer stage is mounted on the top of the two-dimensional motion platform. A wafer workpiece is placed on the top of the wafer stage, and a spectral confocal displacement sensor is mounted above the wafer workpiece. The telescopic end of an electric telescopic rod is fixedly mounted on the top of the spectral confocal displacement sensor, and a gantry structure is fixedly mounted on the top of the electric telescopic rod. Both ends of the bottom of the gantry structure are fixedly mounted on the top of the frame. The two-dimensional motion platform includes two sets of linear motion mechanisms, which are staggered and vertically arranged. This utility model uses the two-dimensional motion platform to drive the two-dimensional movement of the wafer workpiece, and performs non-contact measurement of the wafer workpiece using the spectral confocal displacement sensor. The measurement efficiency is high, and there is no damage to the wafer surface during the measurement process.

Description

Technical Field

[0001] This utility model relates to the field of wafer size measurement technology, specifically a non-contact wafer size measurement device. Background Technology

[0002] With the increasing application of large-size wafers in the semiconductor industry, the measurement of critical wafer dimensions, including TTV thickness variation and flatness, has become increasingly important. Traditional measurement methods, which use probe contact methods, often suffer from problems such as probe wear requiring periodic replacement, low measurement efficiency, and easy scratching of the wafer surface. The industry needs a maintenance-free, highly efficient measurement device that does not damage the wafer surface during the measurement process.

[0003] In view of this, this utility model has developed a non-contact wafer size measurement device. Utility Model Content

[0004] To address the problems in the background technology, this utility model proposes a non-contact wafer size measurement device that can achieve sub-micron level measurement accuracy. It can solve the problems of maintenance, low efficiency, and risk of scratching the wafer surface in traditional contact probe measurement devices. The measurement results can be used to guide the improvement of wafer processing technology.

[0005] The technical solution adopted in this utility model is as follows:

[0006] A non-contact wafer size measurement device includes a frame, a two-dimensional motion platform mounted on the top of the frame, a wafer stage mounted on the top of the two-dimensional motion platform, a wafer workpiece placed on the top of the wafer stage, and a spectral confocal displacement sensor mounted above the wafer workpiece.

[0007] Furthermore, the telescopic end of an electric telescopic rod is fixedly installed on the top of the spectral confocal displacement sensor.

[0008] Furthermore, a gantry structure is fixedly installed on the top of the electric telescopic rod, and both ends of the bottom of the gantry structure are fixedly installed on the top of the frame.

[0009] Furthermore, the two-dimensional motion platform includes two sets of linear motion mechanisms, which are staggered and vertically arranged.

[0010] Furthermore, the linear motion mechanism includes a motor, a fixed frame is fixedly installed on the outside of the motor, a lead screw is fixedly installed on the output end of the motor, the end of the lead screw away from the motor is rotatably installed on the inside of the fixed frame, and a slider is movably installed on the outside of the lead screw, the slider being slidably engaged with the top of the fixed frame.

[0011] Furthermore, the lower motor and the mounting bracket are both fixedly mounted on the top of the frame, the upper mounting bracket is fixedly mounted on the top of the lower slider, and the wafer stage is fixedly mounted on the top of the upper slider.

[0012] The beneficial effects of this utility model are as follows:

[0013] The non-contact wafer size measurement device of this utility model uses a two-dimensional motion platform to drive the wafer workpiece to move in two dimensions, and uses a spectral confocal displacement sensor to perform non-contact measurement on the wafer workpiece. It has high measurement efficiency and does not damage the wafer surface during the measurement process. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0015] Figure 1 A schematic diagram of the overall structure of a non-contact wafer size measurement device provided by this utility model;

[0016] Figure 2 A schematic diagram of a two-dimensional motion platform structure for a non-contact wafer size measurement device provided by this utility model;

[0017] Figure 3 A schematic diagram of a spectral confocal displacement sensor for a non-contact wafer size measurement device provided by this utility model.

[0018] In the picture:

[0019] 1. Frame; 2. Gantry structure;

[0020] 3. Two-dimensional motion platform; 31. Motor; 32. Fixture; 33. Lead screw; 34. Slider;

[0021] 4. Wafer stage; 5. Wafer workpiece; 6. Spectral confocal displacement sensor; 7. Electric telescopic rod. Detailed Implementation

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the present utility model will be briefly introduced below in conjunction with the accompanying drawings and descriptions of the embodiments or the prior art. Obviously, the following description of the structure of the accompanying drawings is only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. It should be noted that the description of these embodiments is used to help understand this utility model, but does not constitute a limitation on this utility model.

[0023] like Figures 1-3As shown, this utility model embodiment provides a non-contact wafer size measurement device, including a frame 1. A computer is installed on the outside of the frame 1 for convenient operation. A two-dimensional motion platform 3 is installed on the top of the frame 1, and a wafer stage 4 is installed on the top of the two-dimensional motion platform 3. A wafer workpiece 5 is placed on the top of the wafer stage 4. The two-dimensional motion platform 3 is used to move the wafer workpiece 5 in a two-dimensional plane. A spectral confocal displacement sensor 6 is installed above the wafer workpiece 5. The spectral confocal displacement sensor 6 can be a model such as CHRocodile M. The spectral confocal displacement sensor 6 is electrically connected to the computer, and the detection data is displayed to the operator through the computer. The operator controls the operation of the spectral confocal displacement sensor 6 through the computer.

[0024] Specifically, the top of the spectral confocal displacement sensor 6 is fixedly equipped with the telescopic end of the electric telescopic rod 7, and a housing is provided on the outside of the spectral confocal displacement sensor 6. The telescopic end of the electric telescopic rod 7 is connected to the housing of the spectral confocal displacement sensor 6, thereby driving the spectral confocal displacement sensor 6 to rise and fall as needed, in order to adjust the distance between the spectral confocal displacement sensor 6 and the wafer workpiece 5, and to ensure that the wafer workpiece 5 ultimately falls within the measurement range of the spectral confocal displacement sensor 6.

[0025] Specifically, a gantry structure 2 is fixedly installed on the top of the electric telescopic rod 7 to fix the electric telescopic rod 7 and the spectral confocal displacement sensor 6. Both ends of the bottom of the gantry structure 2 are fixedly installed on the top of the frame 1.

[0026] Specifically, the two-dimensional motion platform 3 includes two sets of linear motion mechanisms, which are staggered and vertically arranged to drive the spectral confocal displacement sensor 6 to move in the X and Y directions, respectively.

[0027] Specifically, the linear motion mechanism includes a motor 31, a fixed frame 32 is fixedly installed on the outside of the motor 31, a lead screw 33 is fixedly installed at the output end of the motor 31, the end of the lead screw 33 away from the motor 31 is rotatably installed on the inside of the fixed frame 32, and a slider 34 is movably installed on the outside of the lead screw 33. The lead screw 33 is used to convert the rotation of the motor 31 into the linear movement of the slider 34, and the slider 34 is slidably engaged with the top of the fixed frame 32.

[0028] In this embodiment, the rotation of the motor 31 drives the lead screw 33 to rotate, which in turn drives the slider 34 to move linearly.

[0029] Specifically, the lower motor 31 and the fixing bracket 32 ​​are both fixedly installed on the top of the frame 1, the upper fixing bracket 32 ​​is fixedly installed on the top of the lower slider 34, and the wafer stage 4 is fixedly installed on the top of the upper slider 34.

[0030] In this embodiment, two sets of linear motion mechanisms drive the wafer stage 4 and wafer workpiece 5 to move in a two-dimensional plane, enabling the spectral confocal displacement sensor 6 to measure different positions on the surface of the wafer workpiece 5, thereby ultimately obtaining the surface flatness data of the wafer.

[0031] Specific working methods:

[0032] The wafer workpiece 5 can be placed on the wafer stage 4 manually or by a robotic arm. The operator controls the distance between the spectral confocal displacement sensor 6 and the wafer workpiece 5 by extending and retracting the electric telescopic rod 7, ensuring that the wafer workpiece 5 ultimately falls within the measurement range of the spectral confocal displacement sensor 6.

[0033] By controlling the two-dimensional motion platform 3 to drive the wafer workpiece 5 to move, the two-dimensional relative movement between the wafer workpiece 5 and the spectral confocal displacement sensor 6 is realized, enabling the spectral confocal displacement sensor 6 to measure different positions on the surface of the wafer workpiece 5, thereby ultimately obtaining the surface flatness data of the wafer.

[0034] In the spectral confocal displacement sensor 6, a white point light source illuminates the target after passing through a dispersive confocal probe. Different wavelength components in the light source form a longitudinal distribution S'. The light spot on the target returns through a coaxial optical path and then passes through a pinhole aperture before entering the spectrometer. When the distance to the target changes, the wavelength of the focused light also changes, resulting in different spectral distributions in the spectrometer. Therefore, for transparent wafer workpieces 5, the thickness of the wafer workpiece 5 can be measured using a single spectral confocal displacement sensor 6, thereby achieving the TTV parameter index of the wafer.

[0035] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A non-contact wafer size measurement apparatus comprising a frame (1), characterized in that: A two-dimensional motion platform (3) is installed on the top of the rack (1), a wafer stage (4) is installed on the top of the two-dimensional motion platform (3), a wafer workpiece (5) is placed on the top of the wafer stage (4), and a spectral confocal displacement sensor (6) is installed above the wafer workpiece (5).

2. A non-contact wafer size measurement apparatus as recited in claim 1, wherein: The top of the spectral confocal displacement sensor (6) is fixedly equipped with the telescopic end of an electric telescopic rod (7).

3. A non-contact wafer size measurement apparatus as recited in claim 2, wherein: The top of the electric telescopic pole (7) is fixedly installed with a gantry structure (2), and both ends of the bottom of the gantry structure (2) are fixedly installed on the top of the frame (1).

4. The non-contact wafer size measurement apparatus of claim 1, wherein: The two-dimensional motion platform (3) includes two sets of linear motion mechanisms, which are staggered and vertically arranged.

5. A non-contact wafer size measurement apparatus as recited in claim 4, wherein: The linear motion mechanism includes a motor (31), a fixed frame (32) is fixedly installed on the outside of the motor (31), a lead screw (33) is fixedly installed at the output end of the motor (31), the end of the lead screw (33) away from the motor (31) is rotatably installed on the inside of the fixed frame (32), and a slider (34) is movably installed on the outside of the lead screw (33), and the slider (34) is slidably engaged with the top of the fixed frame (32).

6. A non-contact wafer size measurement apparatus as recited in claim 5, wherein: The motor (31) and the mounting bracket (32) located below are fixedly installed on the top of the frame (1), the mounting bracket (32) located above is fixedly installed on the top of the slider (34) located below, and the wafer stage (4) is fixedly installed on the top of the slider (34) located above.

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