Chip positioning method and system

Abstract

The invention provides a chip positioning method and system, and relates to the technical field of semiconductor lasers, and the method comprises the steps: S10, building a visual pixel coordinate system with an x axis and a y axis in the visual field of an image collection mechanism; s20, performing image acquisition on the surface, used for assembling the chip, on the laser through an image acquisition mechanism, and establishing a standard chip image; s30, feature matching with the standard chip image is carried out, the pixel coordinates (X, Y) of the center of the chip to be processed and the positive direction rotation angle theta of the chip to be processed relative to the standard chip are positioned, and the positive direction is the rotation direction around the z axis; s40, moving the laser according to the pixel coordinate (X, Y) of the center of the chip to be processed, so that the center point of the chip to be processed is located at the original point of the pixel coordinate system; and taking the central point of the to-be-processed chip as a rotation center, and rotating the laser by-theta around the z axis, so that the positive rotation angle theta of the to-be-processed chip is zero.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor lasers, and in particular to a chip positioning method and system. Background Art

[0002] The high-power pump module is composed of multiple high-power semiconductor chips and their optical passive devices, where the semiconductor chips are usually packaged in Chip On Substrate (COS).

[0003] Each COS package has a specific mounting area reserved on the module carrier for manual assembly. However, this manual mounting method will cause the COS package to have position and angle deviations after mounting, which increases the complexity of subsequent COS mounting and power-on. Summary of the invention

[0004] The object of the present invention is to provide a chip positioning method and system, which can improve the accuracy of subsequent COS patching and power-on.

[0005] In a first aspect, the present invention provides a chip positioning method, comprising the steps of: S10. In the field of view of the image acquisition mechanism, a visual pixel coordinate system having an x-axis and a y-axis is established; S20. The image acquisition mechanism acquires an image of the surface of the laser for assembling the chip and establishes a standard chip image; S30. Perform feature matching with the standard chip image to locate the pixel coordinates (X, Y) of the center of the chip to be processed and the positive rotation angle θ of the chip to be processed relative to the standard chip, where the positive direction is the rotation direction around the z-axis; S40. According to the pixel coordinates (X, Y) of the center of the chip to be processed, move the laser so that the center point of the chip to be processed is at the origin of the pixel coordinate system; The laser is rotated -θ around the z axis with the center point of the chip to be processed as the rotation center, so that the positive rotation angle θ of the chip to be processed is zero, wherein the x axis, y axis and z axis are perpendicular to each other.

[0006] Furthermore, the step S30 specifically includes the steps of: performing feature matching with the standard chip image to locate the pixel coordinates (X n ,Y n ), and the at least two chips are respectively rotated by an angle θ relative to the positive direction of the standard chip n , n is the chip number; In step S40, after the center point of the previous chip is at the origin of the pixel coordinate system and the positive rotation angle of the chip is zero, the laser is moved according to the position differences △X and △Y between the pixel coordinates of the center of the previous chip and the pixel coordinates of the center of the next chip in the x-axis direction and the y-axis direction, so that the center point of the next chip is at the origin of the pixel coordinate system.

[0007] Furthermore, when the positive rotation angle of the previous chip is zero, according to the difference △θ between the positive rotation angle of the previous chip and the positive rotation angle of the next chip, the laser is rotated -△θ around the z-axis with the center point of the next chip as the rotation center, so that the positive rotation angle of the next chip is zero.

[0008] Furthermore, the chip positioning method further includes the following steps between step S30 and step S40: Compare the positive rotation angle θ of the chip to be processed with a first preset value; When the positive rotation angle θ of the chip to be processed is greater than zero and less than or equal to the first preset value, the chip to be processed is the chip to be adjusted, and the chip to be adjusted performs step S40; When the positive rotation angle θ of the chip to be processed is greater than a first preset value, the chip to be processed is an unqualified chip.

[0009] Furthermore, the chip positioning method further includes the following steps performed between step S30 and step S40: Step S31. Detecting the inclination angle of the top surface of the chip to be processed relative to the plane formed by the x-axis and the y-axis; Step S32: when the tilt angle is greater than zero and less than or equal to a second preset value, the chip to be processed is a chip to be adjusted; When the tilt angle is greater than the second preset value, the chip to be processed is a failed chip.

[0010] Furthermore, the step S31 includes the steps of: Get the side length L of the standard chip image in the x-axis direction and the y-axis direction respectively 标 and W 标 ; Identify the shortest projection lengths L and W of the chip image to be processed in the x-axis direction and the y-axis direction; The step S32 comprises the steps of: When L / L 标 is less than the third preset value, or when W / W 标 When it is less than a fourth preset value, the chip to be processed is an unqualified chip; When L / L 标 is greater than or equal to the third preset value, and W / W 标When it is greater than or equal to the fourth preset value, the chip to be processed is a chip to be adjusted.

[0011] Furthermore, the chip positioning method further includes the following steps performed after step S32: Step S33: Obtain the first inclination angle α of the top surface of the chip to be adjusted relative to the plane formed by the x-axis and the y-axis in the x-axis direction and the y-axis direction respectively. x and the second inclination angle α y ; The step S40 comprises the steps of: According to the first tilt angle α of the chip to be adjusted x and the second inclination angle α y , take the center point of the chip to be adjusted as the rotation center, rotate the laser around the y-axis -α x , so that the first tilt angle α of the chip to be adjusted in the x-axis direction x Zero; take the center point of the chip to be adjusted as the rotation center, rotate the laser around the x-axis -α y , so that the second tilt angle α of the chip to be adjusted in the y-axis direction y is zero.

[0012] Furthermore, the step S33 specifically includes: Assume the coordinates of the center point of the undeflected chip are (X 未 ,Y 未 ); Grab the center coordinates (X 前 ,Y 前 ); Non (X 前 ,Y 前 ) as the rotation center, and the laser is offset by an angle α on the x-axis and y-axis respectively. 改x and α 改y ; Grab the chip center coordinates after the offset (X 后 ,Y 后 ); The first inclination angle α is calculated according to formula 1-formula 4 x and the second inclination angle α y : X 未 / X 前 =cos(α x )Formula 1 X 未 / X 后 = cos(α x +α 改x )Formula 2 Y 未 / Y前 = cos(α y )Formula 3 Y 未 / Y 后 = cos(α y +α 改y )Formula 4 Among them, α 改x and α 改y is a known quantity.

[0013] In a second aspect, the present invention provides a chip positioning system, which applies the above-mentioned chip positioning method, including: an image acquisition mechanism and a mobile platform, wherein the mobile platform is used to fix the laser, and the mobile platform can drive the laser to move in the x-axis and y-axis directions, and rotate around the z-axis.

[0014] In a third aspect, the present invention provides a chip positioning system, which applies the above-mentioned chip positioning method, including: an image acquisition mechanism and a mobile platform, wherein the mobile platform is used to fix the laser, and the mobile platform can drive the laser to move in the x-axis and y-axis directions, rotate around the z-axis, and adjust the pitch angle relative to the plane formed by the x-axis and the y-axis.

[0015] The beneficial effects of the embodiments of the present invention are: Before the subsequent chip processing, such as power-on or patch processing, the method provided by the present invention can be used to first lock the chip to be processed, and locate the pixel coordinates (X, Y) of the center of the chip to be processed in the pixel coordinate system in the field of view of the image acquisition mechanism, as well as the positive rotation angle θ of the chip to be processed relative to the standard chip (hereinafter referred to as the positive rotation angle θ of the chip to be processed); then, move the laser so that the center point of the chip to be processed is at the origin of the pixel coordinate system, and rotate the laser -θ so that the positive rotation angle θ of the chip to be processed is zero. At this time, in the pixel coordinate system, the actual state of the chip to be processed is the standard state, and subsequent patch or power-on processing is performed on it with higher accuracy. Other chips on the laser that need to be patched or powered on are also processed using the same method, and can all be adjusted to the standard state, providing precise positioning for chip patching, power-on and other processes in the laser. BRIEF DESCRIPTION OF THE DRAWINGS In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1A flowchart of a chip positioning method provided by an embodiment of the present invention; Figure 2 The image after binarization processing in step S20 in the chip positioning method provided in an embodiment of the present invention; Figure 3 A schematic diagram of an image of a chip captured by an image capture mechanism in a chip positioning method provided in an embodiment of the present invention.

[0017] Figure 4 A schematic diagram of an image of another chip captured by an image capture mechanism in a chip positioning method provided by an embodiment of the present invention.

[0018] Icons: 1-chip; 2-standard chip image; 3-chip to be processed. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0022] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0023] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0024] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] like Figure 1 As shown, the chip positioning method provided by the present invention comprises the steps of: S10. In the field of view of the image acquisition mechanism, a visual pixel coordinate system having an x-axis and a y-axis is established.

[0026] The origin of the pixel coordinate system may be the center of the image acquisition mechanism, which facilitates the acquisition of a complete image of the laser and focuses on each chip 1. Of course, in other feasible solutions, the origin may also be set at other positions in the field of view.

[0027] The actual distance d corresponding to the side length of a pixel is calculated, so as to establish a proportional relationship between the distance information on the image and the actual distance. The actual distance d corresponding to the side length of a pixel can be calculated using the nine-point marking method, wherein the nine-point marking method is an existing technology and the specific calculation process is not repeated.

[0028] S20. The image acquisition mechanism is used to acquire an image of the surface of the laser for assembling the chip 1 .

[0029] The image acquisition mechanism is located directly above the laser, and acquires images from top to bottom to obtain images of all chips 1 on the laser. The acquired images can be binarized, and then a standard chip image 2 is established.

[0030] like Figure 2 As shown, the physical image of the laser collected by the image acquisition mechanism is processed by visual binarization to generate an image, and feature matching and positioning are subsequently performed based on the image to provide accurate coordinates for the subsequent positioning of the chip 1 on the laser.

[0031] In this embodiment, the shape of the chip 1 image is a rectangle. After the binarization process and before the feature matching, it is necessary to establish a standard chip image 2. The length, width, and gray value information of each pixel of the standard chip image 2 are known quantities. The standard chip image 2 is established by using a visual software tool. This step can be obtained by the prior art.

[0032] S30. Perform feature matching with the standard chip image 2 to locate the pixel coordinates (X, Y) of the center of the chip to be processed 3 and the positive rotation angle θ of the chip to be processed relative to the standard chip 1, where the positive direction is the rotation direction around the z-axis.

[0033] like Figure 3 As shown, by comparing the grayscale value of each pixel of the collected chip 1 image and the standard chip image 2, the pixel coordinates (X, Y) of the center of the chip 3 to be processed and the positive rotation angle θ of the chip 3 to be processed relative to the standard chip 1 can be obtained. This step belongs to the prior art. In the pixel coordinate system, the pixel coordinates (X, Y) of the center point of the chip 3 to be processed and the positive rotation angle θ of the chip 3 to be processed are detected, wherein the positive rotation angle θ refers to the rotation angle of one side of the chip 1 to be processed relative to the same side of the standard chip image 2 around the z-axis on the plane where the x-axis and the y-axis are located, wherein the x-axis, the y-axis and the z-axis are perpendicular to each other.

[0034] S40. According to the pixel coordinates (X, Y) of the center of the chip 3 to be processed, move the laser so that the center point of the chip 3 to be processed is at the origin of the pixel coordinate system; with the center point of the chip 3 to be processed as the rotation center, rotate the laser -θ around the z-axis so that the positive direction rotation angle θ of the chip 3 to be processed is zero.

[0035] When the laser moves, the pixel coordinate system in the field of view remains unchanged. When moving, the center point (X, Y) of the chip 3 to be processed is moved by X*d in the x-axis direction and Y*d in the y-axis direction, so that the center point of the chip 3 to be processed can be at the origin of the pixel coordinate system. When rotating, the laser is rotated -θ around the z-axis with the center point of the chip 3 to be processed as the rotation center. The state of the chip 1 to be processed after completing the above movement and rotation is the standard state.

[0036] Therefore, before the subsequent processing of the chip 1, such as power-on or patch processing, the method provided by the present invention can be used to first lock the chip 3 to be processed, and locate the pixel coordinates (X, Y) and the positive rotation angle θ of the center of the chip 3 to be processed in the pixel coordinate system in the field of view of the image acquisition mechanism; then, move the laser so that the center point of the chip 3 to be processed is at the origin of the pixel coordinate system, and rotate the laser -θ so that the positive rotation angle θ of the chip 3 to be processed is zero. At this time, in the pixel coordinate system, the actual state of the chip 3 to be processed is the standard state, and the subsequent patch or power-on processing is performed on it with higher accuracy. Other chips 1 on the laser that need to be patched or powered on are also processed using the same method, and can all be adjusted to the standard state, providing precise positioning for the processes of patching and powering on the chip 1 in the laser. Step S30 specifically includes the steps of: performing feature matching with the standard chip image 2 to locate the pixel coordinates (X n ,Y n ), and the at least two chips 1 are respectively rotated by an angle θ relative to the positive direction of the standard chip 1 n , n is the chip 1 number; in step S40, after the center point of the previous chip 1 is at the origin of the pixel coordinate system and the positive rotation angle of the chip 1 is zero, according to the position differences △X and △Y of the pixel coordinates of the center of the previous chip 1 and the pixel coordinates of the center of the next chip 1 in the x-axis direction and the y-axis direction, and the actual distance d corresponding to the side length of one pixel, the laser is moved so that the center point of the next chip 1 is at the origin of the pixel coordinate system.

[0037] There are multiple chips 1 on the laser. Before positioning, these chips 1 can be numbered and each chip 1 can be positioned in order from small to large numbers. When positioning the first chip 1, the center point (X 1 ,Y 1 ), move X in the x-axis direction 1 *d, move Y in the y-axis direction 1 *d, that is, the center point of the first chip 1 can be placed at the origin of the pixel coordinate system. When rotating, the center point of the first chip 1 is used as the rotation center, and the laser is rotated around the z axis -θ 1 The state of the first chip 1 that completes the above movement and rotation is the standard state, and subsequent processing can be performed on it.

[0038] After the first chip 1 has completed the subsequent processing, according to the position differences △X and △Y of the pixel coordinates of the center of the first chip 1 and the pixel coordinates of the center of the second chip 1 in the x-axis direction and the y-axis direction, and the actual distance d corresponding to the side length of a pixel, the laser is moved so that the center point of the second chip 1 is at the origin of the pixel coordinate system. Specifically, △X = X 2 -X 1 , △Y = Y 2 - Y 1 After the first chip 1 is positioned, the laser moves △X*d in the x-axis direction and △Y*d in the y-axis direction. The center of the second chip 1 moves to the origin of the pixel coordinate system.

[0039] Similarly, based on the difference △θ between the positive rotation angle of the previous chip 1 and the positive rotation angle of the next chip 1, after the positive rotation angle of the previous chip 1 is zero, the laser can be rotated -△θ around the z-axis with the center point of the next chip 1 as the rotation center to make the positive rotation angle of the next chip 1 zero.

[0040] Taking the first chip 1 and the second chip 1 as an example, the difference in the positive rotation angle between the first chip 1 and the second chip 1 is △θ=θ 2 -θ 1 , when the first chip 1 is positioned, the laser is rotated -△θ around the z-axis with the center point of the second chip 1 as the rotation center, so that the positive direction rotation angle of the second chip 1 is zero.

[0041] The difference between the position and the positive rotation angle of the previous chip 1 and the next chip 1 is calculated in sequence according to the numbering order, so as to complete the positioning one by one, reduce the calculation difficulty, and so on, complete the positioning of all chips 1.

[0042] The chip positioning method also includes a step performed between step S30 and step S40: comparing the positive direction rotation angle θ of the chip to be processed 1 with a first preset value; when the positive direction rotation angle θ of the chip to be processed 1 is greater than zero degrees and less than or equal to the first preset value, the chip to be processed 3 is the chip to be adjusted 1, and step S40 is performed on the chip to be adjusted 1; when the positive direction rotation angle θ of the chip to be processed 1 is greater than the first preset value, the chip to be processed 1 is an unqualified chip 1.

[0043] The first preset value may be 5°. The light emitted by the chip 1 with too large an offset cannot enter the optical element, and there is no need for subsequent processing. Finding unqualified chips 1 in advance can be remedied in advance to avoid increasing subsequent remediation costs. Only chips 1 that meet the conditions proceed to step S40 to achieve compensation of position and positive rotation angle.

[0044] Example 2 On the basis of Example 1, this embodiment further detects the tilt angle. Because when the chip 1 is welded to the laser, the solder under the chip 1 and the laser is unevenly distributed, which may cause the top surface of the chip 1 to be not parallel to the surface of the laser used to install the chip 1. Therefore, in this embodiment, the tilt angle of the chip 1 is detected and angle compensation is performed in subsequent processing.

[0045] The chip positioning method further includes the following steps performed between step S30 and step S40: Step S31: Detect the inclination angle of the top surface of the chip 3 to be processed relative to the plane formed by the x-axis and the y-axis.

[0046] like Figure 4 As shown, in this step, the lens of the image acquisition mechanism is perpendicular to the surface of the laser used to install chip 1. Therefore, the plane formed by the x-axis and the y-axis is parallel to the surface of the laser used to install chip 1. In an ideal state, the top surface of chip 1 should be completely parallel to the surface of the laser used to install chip 1, that is, the inclination angle is zero degree.

[0047] Step S32: When the tilt angle is greater than zero and less than or equal to a second preset value, the chip 3 to be processed is a chip 1 to be adjusted; when the tilt angle is greater than the second preset value, the chip 3 to be processed is an unqualified chip 1.

[0048] The second preset value may be 5°. Only the chip 1 that meets the conditions, i.e. the chip 1 to be adjusted, needs to be compensated for the tilt angle later. The chip 1 with too large offset, i.e. the unqualified chip 1, cannot emit light that enters the optical element, and there is no need for subsequent processing. Finding the unqualified chip 1 in advance can remedy it in advance, avoiding the increase of subsequent remedy costs.

[0049] The specific judgment method is as follows: Step S31 includes the steps of: obtaining the side lengths L of the standard chip image 2 in the x-axis direction and the y-axis direction respectively; 标 and W 标 ; Identify the shortest projection lengths L and W of the chip 3 image to be processed in the x-axis direction and the y-axis direction. That is, if the chip 1 deflects around the x-axis direction, then the shortest projection length of the chip 1 in the y-axis direction detected is less than W 标 Similarly, if chip 1 deflects around the y-axis, the shortest projection of chip 1 on the x-axis is smaller than L 标 Step S32 includes the steps of: when L / L 标 is less than the third preset value, or when W / W 标 When L / L is less than the fourth preset value, the chip 3 to be processed is an unqualified chip 1. 标is greater than or equal to the third preset value, and W / W 标 When the projection size is greater than or equal to the fourth preset value, the chip 3 to be processed is the chip 1 to be adjusted. The third preset value and the fourth preset value can both be 95%. The chip 1 with an unqualified tilt angle can be quickly determined by the projection size, thereby improving the detection efficiency.

[0050] The chip positioning method further includes the following steps after step S32: Step S33. In the x-axis direction and the y-axis direction, respectively obtain the first inclination angle α of the top surface of the chip 1 to be adjusted relative to the plane formed by the x-axis and the y-axis. x and the second inclination angle α y Step S40 comprises the steps of: adjusting the first tilt angle α of the chip 1 according to the first tilt angle α of the chip 1 x and the second inclination angle α y , take the center point of chip 1 to be adjusted as the rotation center, rotate the laser around the y-axis -α x , so that the first tilt angle α of the chip 1 to be adjusted in the x-axis direction x Zero; take the center point of chip 1 to be adjusted as the rotation center, rotate the laser around the x-axis -α y , so that the second tilt angle α of the chip 1 to be adjusted in the y-axis direction y is zero.

[0051] For the chip 1 to be adjusted, it is also necessary to determine the specific value of the tilt angle, so as to facilitate the vertical angle compensation of the chip 1 when the chip 1 is subsequently processed.

[0052] Step S33 specifically includes: assuming that the coordinates of the center point of the chip 1 that is not deflected are (X 未 ,Y 未 ); Grab the center point coordinates (X 前 ,Y 前 ); non(X 前 ,Y 前 ) as the rotation center, and the laser is offset by an angle α on the x-axis and y-axis respectively. 改x and α 改y , α 改x and α 改y is any known value, wherein the rotation center can be one of the four corners of the projection image of the chip 1 to be adjusted; grab the coordinates of the center point of the chip 1 after the offset (X 后 ,Y 后 ); The first inclination angle α is calculated according to formula 1-formula 4 x and the second inclination angle α y : X 未 / X 前 =cos(αx )Formula 1 X 未 / X 后 = cos(α x +α 改x )Formula 2 Y 未 / Y 前 = cos(α y )Formula 3 Y 未 / Y 后 = cos(α y +α 改y )Formula 4 Among them, α 改x and α 改y is a known quantity.

[0053] The first inclination angle α x and the second inclination angle α y The calculation process is the same as that of x Take this as an example, the specific calculation process is as follows: Divide Equation 2 by Equation 1:

[0054] Cross multiplication: Use the angular addition formula for cosines:

[0055] Substituting this into the equation:

[0056] distribute :

[0057] Rearrange items to isolate and sin( ) items:

[0058] Extract on the left :

[0059] Divide both sides by (Assumption ≠0):

[0060] Rearrange to solve for tan( ):

[0061] Solution :

[0062] Among them, X 前 and X 后 is the test value, For the set value, only is an unknown quantity. Find After that, when the chip 1 is subsequently mounted or powered on, the center point of the chip 1 can be used as the rotation center to rotate in the opposite direction around the y-axis. , so that the first tilt angle α x is equal to zero.

[0063] Example 3 The chip 1 positioning system provided by the present invention executes the chip positioning method in Example 1. The system includes: an image acquisition mechanism and a mobile platform. The mobile platform is used to fix the laser. The mobile platform may include a fixed seat. A rotating platform that can rotate around the z-axis is connected below the fixed seat. A two-dimensional slide is connected below the rotating platform. The two-dimensional slide can drive the rotating platform and the fixed seat to move along the x-axis and y-axis directions, so that the chip 3 to be processed can be moved to the origin of the pixel coordinate system and the positive rotation angle of the chip 1 is adjusted to zero.

[0064] Example 4 The system can execute the chip positioning method in Example 1 and Example 2, including: an image acquisition mechanism and a mobile platform, the mobile platform is used to fix the laser. On the basis of Example 3, in this embodiment, the mobile platform also includes a first pitch angle adjustment seat and a second pitch angle adjustment seat arranged in sequence between the fixed seat and the rotating platform along the up and down directions, wherein the first pitch angle adjustment seat can adjust the pitch angle of the fixed seat around the x-axis, and the second pitch angle adjustment seat is arranged below the first pitch angle adjustment seat, and can adjust the pitch angle of the fixed seat around the y-axis to achieve compensation of the vertical angle of the chip 1 on the laser.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A chip positioning method, characterized in that: Includes steps: S10. In the field of view of the image acquisition mechanism, a visual pixel coordinate system having an x-axis and a y-axis is established; S20. The image acquisition mechanism acquires an image of the surface of the laser for assembling the chip and establishes a standard chip image; S30. Perform feature matching with the standard chip image to locate the pixel coordinates (X, Y) of the center of the chip to be processed, and the positive rotation angle θ of the chip to be processed relative to the standard chip (1), wherein the positive direction is the rotation direction around the z-axis; S40. According to the pixel coordinates (X, Y) of the center of the chip to be processed, move the laser so that the center point of the chip to be processed is at the origin of the pixel coordinate system; The laser is rotated -θ around the z axis with the center point of the chip to be processed as the rotation center, so that the positive rotation angle θ of the chip to be processed is zero, wherein the x axis, y axis and z axis are perpendicular to each other.

2. The chip positioning method according to claim 1, characterized in that: The step S30 specifically includes the steps of: performing feature matching with the standard chip image to locate the pixel coordinates (X n ,Y n ), and the at least two chips are respectively rotated by an angle θ relative to the positive direction of the standard chip n , n is the chip number; In step S40, after the center point of the previous chip is at the origin of the pixel coordinate system and the positive rotation angle of the chip is zero, the laser is moved according to the position differences △X and △Y between the pixel coordinates of the center of the previous chip and the pixel coordinates of the center of the next chip in the x-axis direction and the y-axis direction, so that the center point of the next chip is at the origin of the pixel coordinate system.

3. The chip positioning method according to claim 1, characterized in that: When the positive rotation angle of the previous chip is zero, according to the difference △θ between the positive rotation angle of the previous chip and the positive rotation angle of the next chip, the laser is rotated -△θ around the z-axis with the center point of the next chip as the rotation center, so that the positive rotation angle of the next chip is zero.

4. The chip positioning method according to claim 1, characterized in that: The chip positioning method further includes the following steps performed between step S30 and step S40: Compare the positive rotation angle θ of the chip to be processed with a first preset value; When the positive rotation angle θ of the chip to be processed is greater than zero and less than or equal to the first preset value, the chip to be processed is the chip to be adjusted, and the chip to be adjusted performs step S40; When the positive rotation angle θ of the chip to be processed is greater than a first preset value, the chip to be processed is an unqualified chip.

5. The chip positioning method according to claim 1, characterized in that: The chip positioning method further includes the following steps performed between step S30 and step S40: Step S31. Detecting the inclination angle of the top surface of the chip to be processed relative to the plane formed by the x-axis and the y-axis; Step S32: when the tilt angle is greater than zero and less than or equal to a second preset value, the chip to be processed is a chip to be adjusted; When the tilt angle is greater than the second preset value, the chip to be processed is a failed chip.

6. The chip positioning method according to claim 5, characterized in that: The step S31 comprises the steps of: Get the side length L of the standard chip image in the x-axis direction and the y-axis direction respectively 标 and W 标 ; Identify the shortest projection lengths L and W of the chip image to be processed in the x-axis direction and the y-axis direction; The step S32 comprises the steps of: When L / L 标 is less than the third preset value, or when W / W 标 When it is less than a fourth preset value, the chip to be processed is an unqualified chip; When L / L 标 is greater than or equal to the third preset value, and W / W 标 When it is greater than or equal to the fourth preset value, the chip to be processed is a chip to be adjusted.

7. The chip positioning method according to claim 6, characterized in that: The chip positioning method further includes the following steps performed after step S32: Step S33: Obtain the first inclination angle α of the top surface of the chip to be adjusted relative to the plane formed by the x-axis and the y-axis in the x-axis direction and the y-axis direction respectively. x and the second inclination angle α y ; The step S40 comprises the steps of: According to the first tilt angle α of the chip to be adjusted x and the second inclination angle α y , take the center point of the chip to be adjusted as the rotation center, rotate the laser around the y-axis -α x , so that the first tilt angle α of the chip to be adjusted in the x-axis direction x Zero; take the center point of the chip to be adjusted as the rotation center, rotate the laser around the x-axis -α y , so that the second tilt angle α of the chip to be adjusted in the y-axis direction y is zero.

8. The chip positioning method according to claim 7, characterized in that: The step S33 specifically includes: Assume the coordinates of the center point of the undeflected chip are (X 未 ,Y 未 ); Grab the center coordinates (X 前 ,Y 前 ); Non (X 前 ,Y 前 ) as the rotation center, and the laser is offset by an angle α on the x-axis and y-axis respectively. 改x and α 改y ; Grab the chip center coordinates after the offset (X 后 ,Y 后 ); The first inclination angle α is calculated according to formula 1-formula 4 x and the second inclination angle α y : X 未 / X 前 =cos(α x )Formula 1 X 未 / X 后 = cos(α x +α 改x )Formula 2 Y 未 / Y 前 = cos (α y ) Formula 3 Y 未 / Y 后 = cos (α y +α 改y ) Equation 4 Among them, α 改x and α 改y is a known quantity.

9. A chip positioning system, characterized in that: The system applies the chip positioning method described in any one of claims 1 to 4, comprising: an image acquisition mechanism and a mobile platform, wherein the mobile platform is used to fix the laser, and the mobile platform can drive the laser to move in the x-axis and y-axis directions, and rotate around the z-axis.

10. A chip positioning system, characterized in that: The system applies the chip positioning method described in any one of claims 1 to 8, comprising: an image acquisition mechanism and a mobile platform, wherein the mobile platform is used to fix the laser, and the mobile platform can drive the laser to move in the x-axis and y-axis directions, rotate around the z-axis, and adjust the pitch angle relative to the plane formed by the x-axis and the y-axis.

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