TWI728452B - Inspecting system and inspecting method - Google Patents

Abstract

An inspecting system includes a device under test (DUT), a first image capturing device, and a processor. The DUT includes at least one chip, a first wire, and a second wire. The first wire and the second wire are disposed on the at least one chip. The first image capturing device shoots the DUT to generate a plurality of images. The processor generates a plurality of three dimension images of the DUT according to the images. The processor determines a distance between the first wire and the second wire according to the three dimension images.

Description

Detection system and detection method

The content of the embodiments described in this disclosure is related to a detection technology, and particularly to a detection system and a detection method that can be applied to semiconductor detection.

Packaging glue is usually injected during the chip packaging process. Due to the viscosity of the encapsulant, two gold wires that are too close may contact each other and cause a short circuit. In addition, with the development of semiconductor technology, more and more wafers are stacked. This will also increase the probability that any two adjacent gold wires are too close to be short-circuited. In the current technology, only a single layer of gold wire can be tested. However, how to detect whether the multi-layer gold wires are too close is also one of the important issues in this field.

Some embodiments of the present disclosure are related to a detection system. The detection system includes a device to be tested, a first camera device, and a processor. The device under test includes at least one chip, a first gold wire, and a second gold wire. The first gold wire and the second gold wire are arranged on the at least one chip. First camera Shoot the device under test to generate multiple images. The processor generates a plurality of three-dimensional images of the device under test according to the images. The processor determines the distance between the first gold wire and the second gold wire according to the three-dimensional images.

In some embodiments, the processor controls the first camera device to move in a direction, so that the first camera device shoots the device under test at a plurality of positions in the direction to generate the images. The processor uses the images to generate the three-dimensional images based on a focusing and ranging algorithm.

In some embodiments, the at least one chip is disposed on a circuit board. This direction is perpendicular to the extension plane of the circuit board.

In some embodiments, the first camera device includes a lens assembly and an image sensor. The lens assembly is set up with the image sensor. The detection system further includes a light source and a slit. The slit is arranged with the light source so that the irradiation range of an illuminating light falls within the depth of field range of the lens assembly.

In some embodiments, the detection system further includes a second camera device. The processor controls the first camera device and the second camera device to move synchronously, so that the first camera device and the second camera device photograph the device under test. The focus position of the second lens assembly is the same as the focus position of the first lens assembly.

In some embodiments, the first camera device includes a lens assembly and an image sensor. The lens assembly is set up with the image sensor. The lens assembly includes a first reflecting mirror and a second reflecting mirror. When the first gold line is located in the depth range of the lens assembly, the reflected light from the first gold line is sequentially reflected by the second mirror and the first mirror, and then received by the image sensor. The reflected light from the second gold wire is absorbed by a light-absorbing material in the lens assembly.

In some embodiments, the first gold wire and the second gold wire are respectively disposed on the two chips.

Some embodiments of the present disclosure are related to a detection method. The detection method includes: photographing a device under test by a camera device to generate a plurality of images, wherein the device under test includes at least one chip, a first gold wire and a second gold wire, the first gold wire and the second gold wire The gold wire is arranged on the at least one chip; a processor generates a plurality of three-dimensional images of the device under test based on the images; and the processor determines the difference between the first gold wire and the second gold wire based on the three-dimensional images The distance between.

In some embodiments, the step of generating the three-dimensional images by the processor includes: using the images to generate the three-dimensional images by the processor based on a focusing and ranging algorithm.

In some embodiments, the step of generating the images by the camera device includes: controlling the camera device to move in a direction by the processor, so that the camera device can shoot the device under test at a plurality of positions in the direction respectively. Generate these images.

In summary, the detection system and detection method in the present disclosure can solve the problem of the inability to detect whether the multi-layer gold wires are too close due to the shielding of the optical axis.

100, 200, 300, 400, 500‧‧‧Detection system

120‧‧‧Device to be tested

122, 124‧‧‧chip

126‧‧‧Circuit board

140、180‧‧‧Camera device

142, 182, 542‧‧‧ lens assembly

144、184‧‧‧Image sensor

160‧‧‧Processor

301‧‧‧Light source

302‧‧‧Slit

600‧‧‧Detection method

M1, M2‧‧‧Mirror

L1, L2‧‧‧Mirror group

S602, S604, S606‧‧‧Step

W1, W2‧‧‧Gold wire

X, Y, Z‧‧‧direction

In order to make the above and other objectives, features, advantages and embodiments of the present disclosure more comprehensible, the description of the accompanying drawings is as follows: Fig. 1A is a schematic diagram of a detection system according to some embodiments of the present disclosure; Fig. 1B is a top view of the device under test and the camera device in Fig. 1A; Fig. 1C is a schematic diagram of the operation of the detection system in Fig. 1A Figure 1D is a schematic diagram of the operation of the detection system of Figure 1A; Figure 2 is a schematic diagram of a detection system according to some embodiments of the present disclosure; Figure 3 is a schematic diagram of a detection system according to some embodiments of the present disclosure Figure 4 is a schematic diagram of a detection system according to some embodiments of the present disclosure; Figure 5A is a schematic diagram of the operation of a detection system according to some embodiments of the present disclosure; Figure 5B is according to some embodiments of the present disclosure The embodiment shows a schematic diagram of the operation of a detection system; Figure 5C is a schematic diagram of a mirror according to some embodiments of the present disclosure; and Figure 6 is a schematic diagram of a detection method according to some embodiments of the present disclosure flow chart.

The following is a detailed description of embodiments in conjunction with the accompanying drawings, but the provided embodiments are not used to limit the scope of the present disclosure, and the description of the structural operations is not used to limit the order of execution, any recombination of components The structure and the devices with equal effects are all within the scope of this disclosure. In addition, the drawings are for illustrative purposes only, and are not drawn in accordance with the original dimensions. To facilitate understanding, the same elements or similar elements in the following description will be described with the same symbols.

The term "coupled" used in this article can also refer to "electrical coupling", and the term "connected" can also refer to "electrical connection". "Coupling" and "connection" can also refer to two or more components cooperating or interacting with each other.

Please refer to Figure 1A. FIG. 1A is a schematic diagram of a detection system 100 according to some embodiments of the present disclosure. FIG. 1A shows a front view of the detection system 100. As shown in FIG. 1A, the detection system 100 includes a device under test 120, a camera 140 and a processor 160. The processor 160 is coupled to the camera 140. In some embodiments, the processor 160 is used to control the camera 140 to detect the device under test 120. FIG. 1B is a top view of the device under test 120 and the imaging device 140 in FIG. 1A. For the sake of simplicity and ease of understanding, the processor 160 is not shown in FIG. 1B.

In some embodiments, the device under test 120 includes a wafer 122, a lower layer gold wire W1, an upper layer gold wire W2, and a circuit board 126. The lower gold wire W1 and the upper gold wire W2 are disposed on the wafer 122. The chip 122 is disposed on the circuit board 126. Specifically, one end of the lower gold wire W1 and the upper gold wire W2 is connected to the chip 122, and the other end of the lower gold wire W1 and the upper gold wire W2 is connected to the circuit board 126. Taking the example of FIG. 1A as an example, the extension plane of the circuit board 126 is the XY plane.

In some embodiments, the imaging device 140 includes a lens assembly 142 and an image sensor 144. Lens assembly 142 with image sensor 144 Set up. In some embodiments, the lens assembly 142 includes a lens barrel and at least one optical element (for example, a convex lens or a mirror). The camera 140 is used for taking pictures of the device under test 120. In some embodiments, the imaging device 140 is realized by an optical microscope, but the present disclosure is not limited to this. The imaging device 140 has an optical axis, and the direction of the optical axis is the direction Z, for example. The direction of the optical axis (direction Z) is perpendicular to the extension plane (XY plane) of the circuit board 126.

In some embodiments, the processor 160 includes a control circuit (not shown) and a processing circuit (not shown). The control circuit of the processor 160 is used to control the camera device 140 to move along the optical axis direction (direction Z), and to control the camera device 140 to shoot the device under test 120 to generate a plurality of images. The processing circuit of the processor 160 generates a plurality of three-dimensional images of the device under test 120 according to the images, and obtains the positions of all the gold wires according to the three-dimensional images. In this way, the distance between any two gold wires can be judged. In some embodiments, the camera device 140 may be configured on the moving mechanism device, and the control circuit of the processor 160 may control the moving mechanism device to move the camera device 140.

Specifically, the processor 160 controls the camera device 140 to move along the optical axis direction (direction Z). Each movement is for example 1 micron. Every time it moves, the processor 160 controls the camera device 140 to take a picture of the device under test 120. Based on this, assuming that the camera 140 moves 1000 times, 1000 images will be generated. Then, the processor 160 may use, for example, a depth from focus (DFF) algorithm to perform operations on these images to generate a complex three-dimensional image of the device under test 120. Accordingly, the processor 160 can learn the positions of all the gold wires through the three-dimensional images, and then determine the distance between any two gold wires. In some embodiments, any three-dimensional image can be divided into a plurality of regions of interest Region (region of interest; ROI). The processor 160 can analyze the distance between any two gold lines in each region of interest one by one. In some embodiments, when the distance between the two gold wires is equal to or less than 20 microns, it means that the two gold wires are too close to each other and a short circuit is likely to occur.

In the above embodiment, even if the upper gold wire W2 is shielded to the lower gold wire W1 in the optical axis direction (direction Z) (as shown in Figure 1B), the detection system 100 can still detect the multi-layer gold wire (lower gold wire W1). And whether the upper gold wires W2) are too close to each other.

It should be particularly noted that the light source of the detection system 100 may be diffused light. This diffused light can be visible light or invisible light. The image sensor 144 is selected with a light source. In addition, the aperture of the lens assembly 142 can be designed to be sufficient to receive the light information of the lower gold wire W1.

The number of gold wires in the device under test 120 described above is for illustrative purposes only, and various applicable numbers are within the scope of the present disclosure. For example, the device under test 120 may include more than two gold wires.

Please refer to Figure 1C and Figure 1D. FIG. 1C and FIG. 1D are schematic diagrams of the operation of the detection system 100 in FIG. 1A. For ease of understanding, FIG. 1C and FIG. 1D show the left side view of the detection system 100. As mentioned above, the processor 160 will control the camera device 140 to move in the optical axis direction (direction Z), so that the camera device 140 can photograph the device under test 120 at different positions in the optical axis direction (direction Z) to generate Multiple images. For example, the imaging device 140 in Figure 1C captures the device under test 120 at a lower position, and the camera 140 in Figure 1D captures the device under test 120 at a higher position.

Please refer to Figure 2. FIG. 2 is a schematic diagram of a detection system 200 according to some embodiments of the present disclosure. FIG. 2 shows a front view of the detection system 200. The difference between the inspection system 200 in FIG. 2 and the inspection system 100 in FIG. 1A is that the inspection system 200 in FIG. 2 includes a plurality of stacked wafers, such as wafer 122 and wafer 124. The lower layer gold wire W1 is disposed on the wafer 122. The upper gold wire W2 is disposed on the wafer 124. Specifically, one end of the lower layer gold wire W1 is connected to the chip 122 and the other end of the lower layer gold wire W1 is connected to the circuit board 126. One end of the upper layer gold wire W2 is connected to the chip 124 and the other end of the upper layer gold wire W2 is connected to the circuit board 126. The detection system 200 in FIG. 2 has a similar operation to the detection system 100 in FIG. 1A, so it will not be repeated here.

The number of the above-mentioned wafers is for illustrative purposes only, and various applicable numbers are within the scope of the present disclosure. For example, the inspection system 200 may include more than two stacked wafers.

Please refer to Figure 3. FIG. 3 is a schematic diagram of a detection system 300 according to some embodiments of the present disclosure. The difference between the detection system 300 in FIG. 3 and the detection system 100 in FIG. 1A is that the detection system 300 further includes a light source 301 and a slit 302. The slit 302 is provided in conjunction with the light source 301. For example, the slit 302 is provided on the light emitting side of the light source 301. The slit 302 is used to limit the irradiation range of the irradiation light of the light source 301 so that the irradiation range of the irradiation light passing through the slit 302 falls within the depth of focus (DOF) of the lens assembly 142. Taking the example of FIG. 3 as an example, when the depth of field range of the lens assembly 142 is the area around the lower gold wire W1, the irradiation range of the irradiated light passing through the slit 302 is also the area around the lower gold wire W1. In this way, it is possible to prevent the gold line (for example, the upper gold line W2) located outside the depth of field from interfering with the image quality. The detection system 300 in FIG. 3 has a similar operation to the detection system 100 in FIG. 1A, so it will not be repeated here.

Please refer to Figure 4. FIG. 4 is a schematic diagram of a detection system 400 according to some embodiments of the present disclosure. The difference between the detection system 400 in FIG. 4 and the detection system 100 in FIG. 1A is that the detection system 400 further includes a camera 180. The imaging device 180 includes a lens assembly 182 and an image sensor 184. The lens assembly 182 is configured in conjunction with the image sensor 184. In some embodiments, an angle is formed between the optical axis direction of the imaging device 180 and the optical axis direction of the imaging device 140, and the focus position of the lens assembly 182 is the same as the focus position of the lens assembly 142. The processor 160 controls the camera 140 and the camera 180 to move synchronously, so that the camera 140 and the camera 180 both shoot the device under test 120. The image captured by the camera device 180 can be used to compensate the image captured by the camera device 140. Taking the example of FIG. 4 as an example, when the focal position of the lens assembly 142 is the area around the lower gold wire W1, the image captured by the imaging device 140 may be interfered by the upper gold wire W2. The image captured by the camera 180 will not be disturbed by the upper gold wire W2. Therefore, the image captured by the camera device 180 can be used to compensate the image captured by the camera device 140. In this way, the processor 160 can obtain images with better image quality.

The number of the above-mentioned imaging devices is only for the purpose of example, and various applicable numbers are within the scope of the present disclosure. For example, the detection system 400 may include three or more than three camera devices.

Please refer to Figure 5A and Figure 5B. Figures 5A and 5B show the operation of a detection system 500 according to some embodiments of the present disclosure. Schematic. The difference between the detection system 500 in FIG. 5A and the detection system 100 in FIG. 1A is that the lens assembly 542 in FIG. 5A includes a mirror M1 and a mirror M2. Please refer to Figure 5C. FIG. 5C is a schematic diagram of the mirror M2 drawn according to some embodiments of the present disclosure. In some embodiments, the mirror M2 is a mirror that is arranged around the wall of the lens barrel and has a hollow center portion. In addition, a lens group L1 is provided on the side of the lens assembly 542 close to the chip M1, and a lens group L2 is provided between the lens assembly 542 and the image sensor 144. In some embodiments, the lens group L1 and the lens group L2 are respectively realized by a convex lens, but the present disclosure is not limited thereto. Various implementations of the lens group L1 and the lens group L2 are within the scope of the present disclosure. Taking the example of FIG. 5A as an example, when the lower layer gold wire W1 is located in the depth of field range of the lens assembly 542, the reflected light from the lower layer gold wire W1 enters the lens assembly 542 from a part other than the mirror M1. With the configuration of the mirror group L1, the reflected light from the lower gold wire W1 will become parallel light after passing through the mirror group L1. This parallel light is sequentially reflected by the mirror M2 and the mirror M1. Then, the reflected light will be received by the image sensor 144 after passing through the lens group L2. In addition, due to the configuration of the optical elements, the reflected light of the upper gold wire W2 becomes non-parallel light after entering the lens assembly 542. This non-parallel light will be absorbed by the light-absorbing material in the lens assembly 542. In this way, the upper layer gold wire W2 can be prevented from interfering with the image quality. Similarly, in the example of FIG. 5B, when the processor 160 controls the imaging device 140 to move up so that the upper gold wire W2 is located in the depth of field range of the lens assembly 542, the reflected light from the upper gold wire W2 is from outside the mirror M1 Partially enters the lens assembly 542, as shown in Figure 5B. With the configuration of the optical elements, the reflected light from the upper gold wire W2 will become parallel light after passing through the mirror group L1. This parallel light is sequentially reflected by the mirror M2 and the mirror M1. Next, after reflection The light passing through the lens group L2 will be received by the image sensor 144. As described above, after the camera 140 captures images at different positions, the processor 160 can generate a plurality of three-dimensional images of the device under test 120 based on the images and learn the positions of all the gold wires based on the three-dimensional images. The detection system 500 in FIG. 5A and FIG. 5B has similar operations to the detection system 100 in FIG. 1C and FIG. 1D, so it will not be repeated here.

Please refer to Figure 6. FIG. 6 is a flowchart of a detection method 600 according to some embodiments of the present disclosure. The detection method 600 includes step S602, step S604, and step S606. In some embodiments, the detection method 600 is applied to the detection system 100 in FIG. 1A, but the present disclosure is not limited thereto. For ease of understanding, the detection method 600 will be discussed in conjunction with Figures 1A-1D.

In step S602, the device under test 120 is photographed by the camera device 140 to generate a plurality of images. In some embodiments, the processor 160 controls the camera device 140 to move along the optical axis direction (direction Z), so that the camera device 140 takes pictures of the device under test 120 at different positions in the optical axis direction (direction Z) to produce Multiple images corresponding to different positions.

In step S604, the processor 160 generates a plurality of three-dimensional images of the device under test 120 according to the images. In some embodiments, the processor 160 uses a focusing and ranging algorithm to perform operations on the images captured by the camera 140 to generate the three-dimensional images of the device under test 120.

In step S606, the processor 160 determines the distance between the lower gold wire W1 and the upper gold wire W2 according to the three-dimensional images. In some embodiments, after the three-dimensional images of the device under test 120 are constructed, any A three-dimensional image can be divided into a plurality of regions of interest. The processor 160 analyzes each region of interest one by one to determine the distance between any two gold lines in each region of interest.

The above description of the detection method 600 includes exemplary operations, but these operations of the detection method 600 need not be executed in the order shown. The sequence of the operations of the detection method 600 can be changed, or the operations can be performed simultaneously, partially performed simultaneously, or partially omitted under appropriate circumstances, all within the spirit and scope of the embodiments of the present disclosure.

It is worth noting that, in some embodiments, the detection method 600 can also be implemented as a computer program. The computer program is stored in the memory. When the computer program is executed by the processor 160, an electronic device, or a computer in FIG. 1A, the execution device executes the detection method 600. Computer programs can be stored in a non-transitory computer readable recording medium, such as a read-only memory, a flash memory, a floppy disk, a hard disk, a CD, a flash disk, a flash disk, A magnetic tape, a database that can be read from the Internet, or any recording medium with the same function that can be thought of by a person with ordinary knowledge in the technical field of the present disclosure.

In summary, the detection system and detection method in the present disclosure can solve the problem of the inability to detect whether the multi-layer gold wires are too close due to the shielding of the optical axis.

Although the present disclosure has been disclosed in the above manner, it is not intended to limit the present disclosure. Anyone with ordinary knowledge in the field can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure The scope of protection shall be subject to the scope of the attached patent application.

100‧‧‧Detection System

120‧‧‧Device to be tested

122‧‧‧chip

126‧‧‧Circuit board

140‧‧‧Camera Device

142‧‧‧lens assembly

144‧‧‧Image sensor

160‧‧‧Processor

W1, W2‧‧‧Gold wire

X, Y, Z‧‧‧direction

Claims (8)

A detection system includes: a device to be tested, including at least one chip, a first gold wire, and a second gold wire, wherein the first gold wire and the second gold wire are disposed on the at least one chip; A camera device that shoots the device under test to generate a plurality of images; a processor generates a plurality of three-dimensional images of the device under test based on the images, and the processor determines the first gold based on the three-dimensional images The distance between the wire and the second gold wire; and a second camera device, the processor controls the first camera device and the second camera device to move synchronously, so that the first camera device and the second camera device The device photographs the device under test, wherein the focus position of the second camera device is the same as the focus position of the first camera device. The detection system according to claim 1, wherein the processor controls the first camera device to move in a direction, so that the first camera device respectively shoots the device under test at a plurality of positions in the direction to generate the The processor generates the three-dimensional images using the images based on a focusing and ranging algorithm. The inspection system according to claim 2, wherein the at least one chip is disposed on a circuit board, and the direction is perpendicular to the extension plane of the circuit board. The detection system according to claim 1, wherein the first camera device includes a lens assembly and an image sensor, and the lens assembly is configured with the image sensor, wherein the lens assembly includes a first reflector and A second reflector. When the first gold line is located in the depth of field range of the lens assembly, the reflected light from the first gold line is sequentially reflected by the second reflector and the first reflector and then is reflected by the image The detector receives, and the reflected light from the second gold wire is absorbed by a light-absorbing material in the lens assembly. The inspection system according to claim 1, wherein the first gold wire and the second gold wire are respectively arranged on two chips. A detection method includes: generating a plurality of images by shooting a device under test by a first camera device, wherein the device under test includes at least one chip, a first gold wire, and a second gold wire, and the The first gold wire and the second gold wire are disposed on the at least one chip; a processor generates a plurality of three-dimensional images of the device under test based on the images; and the processor determines the three-dimensional images based on the three-dimensional images The distance between the first gold wire and the second gold wire; and the processor controls the first camera device and the second camera device to move synchronously, so that the first camera device and the second camera device The device under test is photographed, wherein the focus position of the second camera device is the same as the focus position of the first camera device. The detection method according to claim 6, wherein the step of generating the three-dimensional images by the processor comprises: generating the three-dimensional images by the processor based on a focusing and ranging algorithm using the images. The detection method according to claim 6, wherein the step of generating the images by the first camera device includes: controlling the first camera device to move in a direction by the processor, so that the first camera device The device under test is photographed at a plurality of positions in the direction to generate the images.

Images