TWI756555B - An alignment device for semiconductor wafer inspection - Google Patents

Abstract

The device of the invention is mainly to resolve the angle deviation problem during the inspection of the wafer. Through the present invention, it can greatly improve the efficiency of wafer inspection.

Description

A wafer defect detection and alignment device

The device of the present invention mainly aims to improve the angle deviation problem in the wafer inspection process. Through the angle rotating device disclosed in the present invention, the purpose of greatly improving the operation efficiency of the prior art can be achieved.

In the prior art, the wafer sample is placed as shown in Figure 1 for inspection. The inspection wafer is 100, of which 101 is the center of the optical axis. The center point of the light source and the imaging device are preset on this axis. The sample placement angle 102 and the field of view There is a θ angle error 104 in the range moving direction 103. During the shooting process, when the image imaging range moves with the moving direction, the angle error can be corrected through the software if the angle error is small. If the situation outside the range 105 occurs, it must be used together with another vertical correction to overcome this problem, which will consume extra time and reduce the detection efficiency. When the demand for magnification continues to increase and the visual range continues to shrink, the problem of affecting operational efficiency will become more significant.

In order to overcome the wafer placement angle error, the patent WO2009011417A1 uses an external inspection device to rotate the flat sample in advance. During the rotation of the object to be inspected, multiple positions of the object to be inspected are photographed. Know the relative position of the object to be inspected and the photographing device, and then correct the relative position obtained by the inspection device through the subsequent picking and placing process of the equipment; however, there are unpredictable mechanical errors in the picking and placing process, resulting in insufficient alignment accuracy The problem still exists.

Patent CN103811387A discloses a method and device for wafer pre-alignment. The device includes an angle adjustment mechanism, and the angle adjustment mechanism directly drives the wafer to rotate or translate to drive the wafer to a desired test position; this method is corrected by direct drive Angle, overcoming the corrected pick and place action may lead to angle error, but in this angle adjustment mechanism, the translation component needs to carry the rotating component to move, so under the shooting conditions where the translation component is constantly moving, the translation component must withstand the gravitational acceleration of the rotating component , and shaking the overall operation is not conducive to stable shooting.

Therefore, the present invention discloses an angle rotation device, which can make the sample rotate along the center of the optical axis 104, the sample to be tested is directly aligned in the optical detection area, and is fixed on the sample stage and does not move after the operation is completed. In the technology, there is a pick-and-place error, or the mechanism is huge, and the problem of shaking is easy to occur during operation; the structure and implementation are as follows.

The device of the present invention mainly aims to improve the angle deviation problem in the wafer inspection process. Through the angle rotating device disclosed in the present invention, the purpose of greatly improving the operation efficiency of the prior art can be achieved.

In order to achieve the above objectives, the present invention provides a detection device, the detection device mainly includes a light source device, an image capture device, an angle rotation device, a detection platform and a motion mechanism, and the illumination area of the light source device is an area with a diameter of 1-400mm; The pick-up device is used to obtain the penetrating image information; the angle rotation device can lift the sample and rotate. The interior of the angle rotating device is designed with a space for accommodating the light source device or the image capture device. The operation mode can be that the internal device can simultaneously lift up, or the internal device can move independently; the detection platform is used to carry the sample to be tested to obtain different positions. Through the combination of the above devices, the final image acquisition result can obtain image information with penetration.

Different from the prior art, the angle rotating device of the present invention is located in the detection area, and is different from the prior art using an external positioning device, which is then moved to the detection area after the positioning is completed, and the angle rotating device is not fixed with the sample and moves synchronously. , the angle correction process will first lift the angle rotating device upward, lift the sample to correct the angle, then put it down, and place it on the plane of the detection platform. The movement of different image capturing positions is achieved by the motion mechanism; further explained, because the light source device and the image capture device are maintained on the same axis, there is no relative displacement, the image capturing of different positions is achieved by moving the axis or moving the detection platform by the motion mechanism. Therefore, the momentum of the moving parts can be reduced and the shaking can be reduced; in addition, the present invention and the light source device are not combined with the detection platform, and the motion mechanism does not need to load the light source device and the detection platform at the same time, so it can simultaneously obtain penetrating images and reduce shaking. , especially if the motion mechanism only moves the detection platform as the best way.

The wavelength used by the light source device in the present invention needs to be matched with the wafer substrate. If the substrate material is silicon or gallium arsenide, the wavelength selection range can be 800-1700 nm; the wavelength of gallium nitride or aluminum oxide substrate is selected The range can be 200-1100nm; the wavelength selection range of the silicon carbide substrate can be 100-1000nm.

In addition, in the present invention, the position of the light source device can be located above or below the sample to be tested.

In the present invention, the image capture device can be located above or below the sample to be tested, but relative to the other side of the light source device, and the relative position to the light source device is fixed, maintaining a fixed axis and no relative movement.

In addition, the detection platform in the present invention is designed to be transparent.

In order to make the above objects, technical features and advantages easier to understand, the following detailed descriptions are given with reference to the preferred embodiments in conjunction with the drawings.

100: Inspect the wafer

101: Optical axis center

102: Sample placement angle

103: The direction of movement of the field of view

104: θ angle error

105: The sample taken is outside the field of view

200: Wafer Defect Inspection Device

201: Light source installation

202: Angle Rotation Device

203: Image capture device

204: Sample carrying platform

205: Sports Equipment

206: Optical axis center

301: The angle rotation device lifts the cylinder

302: The light source device lifts the cylinder

400: Wafer Defect Inspection Device

401: Light source device

402: Angle Rotation Device

403: Image capture device

404: Sample carrying platform

405: Sports Equipment

501: The angle rotation device lifts the cylinder

502: The image capture device lifts the Z axis

Figure 1 is a schematic diagram of the angle error of wafer defect detection

FIG. 2 is a schematic diagram of a wafer defect detection device.

Figure 3 is another detailed design of the angle rotation mechanism

FIG. 4 is another schematic diagram of the wafer defect detection device

Figure 5 is another detailed design of the angle rotation mechanism

The present invention discloses a wafer defect detection device. The specific embodiments of the present invention will be described below in conjunction with the drawings. Please refer to FIG. 2: The wafer defect detection device 200 of the present invention includes a light source device 201, an angle rotation device 202, The image capturing device 203 , the supporting platform 204 and the motion mechanism 205 , wherein the center line connecting the light source device 201 and the image capturing device 203 is the center of the optical axis 206 , and the substrate of the sample to be tested is silicon (Si).

The wavelength of the light source device 201 is 800-1700nm and the diameter of the irradiation range is 10mm, and the light source device 201 is fixed in the angle rotation device 202; with reference to the calculation method in FIG. After the action is to lift the carrying platform 204 upward, the carrying platform 204 is rotated to turn the sample to be tested fixed on it to the correct detection angle, and the light source device 201 is fixed inside, and the light source device 201 is driven to move together when the lifting or rotating action is performed. ; The detailed design of the angle rotation mechanism can also be as shown in FIG. 3. The angle rotation device 202 and the light source device 201 can be lifted independently through the cylinders 301 and 302, so that the height position of the light source can be controlled more accurately; the image capture device 203 is a CCD and The lens barrel is assembled and formed, and the image capture device 203 is fixed on the mechanical component without any relative position movement to the light source device 201; when using, the sample to be tested is It is fixed above the carrying platform 204 and can allow the light source provided by the light source device 201 to penetrate, and the moving device 205 can be an XY moving platform to drive the carrying platform 204 to independently move in the XY direction.

Through the combination of the above devices, the angle rotating device 202 has a space for accommodating the light source device 201, so that the 800-1700nm wavelength light source can penetrate the wafer substrate, and obtain the penetrating image inside the wafer or the substrate after the wafer is cut. According to the condition of the edge of the material, the final imaging result can know the abnormal position through the gray scale change. At the same time, it is different from the design of the prior art DE102016101452B4. The supporting platform 204 and the light source device 201 in this embodiment are not combined motion devices, which can improve the shaking problem. In addition, the angle rotation device 202 can lift the supporting platform 204 and the sample on it in the detection range, and then lower the angle to the original detection range after correcting the angle, so as to improve the error problem of the placement angle of the sample; and the position of the 10mm light source is fixed to the image capture device The optical axis center 206 can be analyzed with a stable light source, which has many advancements.

On the other hand, another embodiment of this embodiment may be shown in FIG. 4 , which is used to inspect gallium arsenide (GaAs) wafers. The wafer defect inspection device 400 of the present invention includes a light source device 401 and an angle rotation device 402 , an image capture device 403 , a carrying platform 404 and a motion mechanism 405 .

The wavelength of the light source device 401 is 800-1700 nm and the diameter of the irradiation range is 20 mm. The angle rotation device 402 is mainly used to rotate the carrying platform 404 and the sample to be tested on it, and there is an image capturing device 403 in the inner space. 403 can use a microscope group combined with a camera, and digitally transmit the imaging results, and the capture device 403 and the light source device 401 are located on the same axis, but the light source device 401 and the capture device 403 can be moved simultaneously through the movement device 405, so that the The axis is moved to different detection positions, the detection sample is fixed on the bearing platform 404, and the relative position of the sample is maintained between the light source device 401 and the capture device 403; and the detailed design of the angle rotation device 402 can also be as shown in FIG. 5, the angle rotation The device 402 and the image capture device 403 can pass through independently The air cylinder 501 and the Z axis 502 are lifted up, so that the position of the image capturing device 403 can be controlled more precisely;

Through the combination of the above devices, the position of the light source device 401 is different from that of the first embodiment, but the θ angle error 104 in the sample placement can be calculated with reference to FIG. Purpose: at the same time, the detection sample is located between the light source device 401 and the image capture device 403, and the light source device 401 and the image capture device 403 are installed on a relatively fixed axis without any relative displacement, and the motion device 405 moves the above axis at the same time To different positions, images of penetrating information can be obtained, and the same stable light source is used in different positions to improve the grayscale error problem.

The above-mentioned embodiments are only used to illustrate the embodiments of the present invention and to illustrate the technical characteristics of the present invention, and are not intended to limit the protection scope of the present invention. Any changes or equality arrangements that can be easily accomplished by those skilled in the art fall within the claimed scope of the present invention, and the scope of protection of the present invention should be subject to the scope of the patent application.

200: Wafer Defect Inspection Device

201: Light source installation

202: Angle Rotation Device

203: Image capture device

204: Sample carrying platform

205: Sports Equipment

206: Optical axis center

Claims (5)

A wafer defect detection device capable of obtaining both surface and penetrating image information, the wafer defect detection device comprises: a light source device that illuminates a sample area to be tested with a diameter of 1-400mm; an image capture device an acquisition device, used to obtain the penetration and surface information images of the sample to be tested; an angle rotation device, used to lift the sample and rotate, and the angle rotation device has a space for accommodating the light source device or the image capture device, which is accommodated therein The light source or image capture device can be lifted or rotated simultaneously or separately with the angle rotation device; a detection platform is used to carry the sample to be tested; a motion mechanism is used to move the detection platform or move the light source and image capture at the same time device. The wafer defect detection device according to claim 1, wherein the wavelength of the light source device needs to be matched with the wafer substrate. If the substrate material is silicon or gallium arsenide, the wavelength selection range can be 800-1700 nm; gallium nitride Or the wavelength selection range of alumina substrate can be 200-1100nm; the wavelength selection range of silicon carbide substrate can be 100-1000nm. The wafer defect inspection device according to claim 1, wherein the position of the light source device can be located above or below the sample. The wafer defect inspection device according to claim 1, wherein the image capture device is located on the other side of the light source device, and the relative position of the image capture device and the light source device is fixed, and there is no horizontal movement of the relative position. The wafer defect inspection apparatus according to claim 1, wherein the inspection platform is designed to be transparent.

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