Lead frame laser scanning and process usability determination method and system

Abstract

The present application relates to the field of optical measurement and profile detection, and particularly relates to a lead frame laser scanning and process usability determination method and system. The method comprises: determining the dark area center position and the recess center position of the surface abnormal area of the bonding area through the laser scanning reflection intensity image and the three-dimensional topography image, calculating the directional spatial offset vector module length, determining the geometric type of the surface abnormal profile of the bonding area, combining the step interference modulation characteristic amplitude to distinguish the plated layer penetration state and the non-penetration state, extracting the surface profile depth value for the non-penetration state and comparing it with the bonding pressure and the bonding time adjustable range, and outputting the process usability determination result. The present application is associated with the bonding pressure adjustable range and the bonding time adjustable range, thereby realizing the accurate determination of the process usability of the bonding area on the basis of optical profile measurement, and effectively overcoming the shortcomings of the existing single threshold method in the micro-scale surface abnormal profile scene.

Description

Technical Field

[0001] This invention relates to the field of optical measurement and contour detection technology, and in particular to a method and system for laser scanning of lead frames and determination of process availability. Background Technology

[0002] As a key structure in semiconductor packaging that carries the chip and connects to external circuits, the quality of the bonding area plating directly affects the wire bonding strength and packaging reliability. Existing laser scanning detection methods can quickly identify surface anomalies in the bonding area by acquiring reflection intensity images and three-dimensional topography images, combined with threshold segmentation and height analysis. They exhibit high detection efficiency in conventional scenarios where the plating is flat and the surface anomaly contour size is large.

[0003] However, when the coating thickness in the bonding region is only a few micrometers and the size of the surface anomaly contour is close to the diameter of the laser spot, geometric surface anomalies such as shallow scratches and coating pinholes appear as low-reflection dark areas in the reflection intensity image. While non-geometric surface anomalies such as oxide spots also appear as dark areas, they do not have a concave morphology. Existing methods struggle to distinguish between the two, and depth variations in the three-dimensional morphology image are difficult to differentiate from surface roughness noise. Existing methods often rely on a single intensity or height threshold, lacking joint analysis of the geometric features of the surface anomaly contour edges and the coating penetration state. This leads to unstable results in the identification of bonding region surface contour types and the determination of process usability, resulting in frequent misjudgments and omissions.

[0004] Therefore, there is an urgent need to study a leadframe laser scanning and process availability determination method that can integrate reflection intensity and three-dimensional morphology information to improve the accuracy of surface contour feature extraction of the bonding area and the assessment of bonding process adjustability. Summary of the Invention

[0005] To overcome the inaccuracy in the correlation between bonding region surface profile measurement and process availability determination, this invention provides a method and system for lead frame laser scanning and process availability determination.

[0006] The technical implementation of the present invention is a method for laser scanning and process availability determination of lead frames, comprising the following steps:

[0007] S1: Determine the center position of the dark area and the center position of the depression of the abnormal area on the surface of the bonding region from the laser scanning reflection intensity image and the three-dimensional topography image respectively, and calculate the magnitude of the directional spatial offset vector based on the center position of the dark area and the center position of the depression.

[0008] S2: Determine the geometric type of the abnormal profile on the bonding area surface based on the magnitude of the directional spatial offset vector, and distinguish between the coating penetration state and the non-penetration state by combining the step interference modulation characteristic amplitude. The coating penetration state is marked as unusable, and the non-penetration state enters the subsequent adjustability evaluation.

[0009] S3: Determine the center position of the dark area, the center position of the depression, and the offset direction on both sides of the abnormal contour area of ​​the bonding area in the non-penetrated state. Based on the consistency between the first side offset direction and the second side offset direction, extract the maximum depth value or the average depth value of the surface contour.

[0010] S4: Extract the surface profile depth value based on the consistency of the offset direction, compare the surface profile depth value with the adjustable range of bonding pressure, if it fails, mark the process as unusable, if it passes, further calculate the bonding time extension amount and compare it with the adjustable range of bonding time, if it fails, mark the process as unusable, if it passes, perform the bonding pressure reduction operation and the bonding time extension operation, and adjust the laser scanning method to high resolution scanning mode to re-scan the abnormal areas on the bonding area surface.

[0011] Preferably, determining the center position of the dark area and the center position of the depression in the abnormal area of ​​the bonding region surface from the laser scanning reflection intensity image and the three-dimensional topography image respectively includes:

[0012] In the reflection intensity image, extract the set of pixels below the preset intensity threshold in the abnormal area of ​​the bonding region surface; calculate the arithmetic mean of the horizontal and vertical coordinates of the pixel set respectively, and use them as the horizontal and vertical coordinates of the dark area center.

[0013] In the three-dimensional topography image, the set of height values ​​in the abnormal area of ​​the bonding zone surface is extracted; the set of height values ​​is fitted with a quadratic surface to obtain the fitted surface; the abscissa and ordinate of the lowest point of the fitted surface are extracted respectively as the abscissa and ordinate of the depression center.

[0014] Preferably, the step of calculating the magnitude of the directional spatial offset vector based on the center position of the dark area and the center position of the depression includes:

[0015] Subtracting the x-coordinate of the dark area center from the x-coordinate of the depression center yields the x-component of the directional spatial offset vector.

[0016] Subtracting the ordinate of the dark area center from the ordinate of the depression center yields the ordinate component of the directional spatial offset vector.

[0017] The sum of squares of the directional spatial offset vector is obtained by adding the square of the horizontal component of the directional spatial offset vector to the square of the vertical component of the directional spatial offset vector.

[0018] The square root of the sum of squares of the directional spatial offset vectors is calculated to obtain the magnitude of the directional spatial offset vector.

[0019] Preferably, the step of determining the geometric type of the abnormal contour of the bonding region surface based on the magnitude of the directional spatial offset vector, and distinguishing between the coating penetration state and the non-penetration state by combining the step interference modulation characteristic amplitude, wherein the coating penetration state is marked as unusable, and the non-penetration state proceeds to the subsequent adjustability evaluation, includes:

[0020] When the magnitude of the directional spatial offset vector is higher than the preset directional offset threshold, the abnormal contour of the bonding area surface is determined to be of geometric type.

[0021] If it is a geometric type, then extract the height step and speckle intensity spatial sequence of the edge transition region in the abnormal contour of the bonding area surface respectively;

[0022] The spatial spectrum is obtained by performing a Fourier transform on the spatial sequence of speckle intensity.

[0023] Based on height step Laser wavelength Angle of incidence and system space sampling reference length ,according to Calculate the expected spatial frequency f of the step interference modulation;

[0024] The amplitude at the expected spatial frequency in the spatial spectrum is taken as the characteristic amplitude of step interference modulation.

[0025] When the amplitude of the step interference modulation feature is higher than the preset step interference modulation amplitude threshold, the bonding area coating corresponding to the abnormal contour of the bonding area surface of the geometric type is determined to be in a penetrating state, and the bonding area is marked as unusable for the process.

[0026] When the amplitude of the step interference modulation feature is lower than the preset step interference modulation amplitude threshold, the bonding area coating corresponding to the abnormal surface profile of the bonding area of ​​the geometric type is determined to be in an unpenetrated state, and then proceeds to the subsequent adjustability evaluation.

[0027] When the magnitude of the directional spatial offset vector is lower than or equal to the preset directional offset threshold, the abnormal contour of the bonding area surface is determined to be a non-geometric material type, and the bonding area is directly marked as unusable for the process.

[0028] Preferably, determining the center position of the dark area, the center position of the depression, and the offset direction of the two sides of the abnormal contour region on the surface of the bonding area in the non-penetrated state includes:

[0029] Perform edge recognition on the abnormal contour area of ​​the bonding region surface in the non-penetrated state to obtain the first side edge on the side closer to the center of the bonding region and the second side edge on the side farther from the center of the bonding region.

[0030] The pixel with the lowest gray value in the first edge is taken as the center position of the first dark area;

[0031] The point with the lowest height value on the first side edge is taken as the center position of the first side depression;

[0032] By comparing the center position of the first side depression with the center position of the first side dark area, the offset direction of the first side is obtained. The offset direction of the first side is towards the center of the bonding area or away from the center of the bonding area.

[0033] Preferably, determining the center position of the dark area, the center position of the depression, and the offset direction of the two sides of the abnormal contour region on the surface of the bonding area in the non-penetrated state includes:

[0034] The pixel with the lowest gray value in the second edge is taken as the center position of the dark area on the second side;

[0035] The point with the lowest height value on the second side edge is taken as the center position of the second side depression;

[0036] By comparing the center position of the second side depression with the center position of the second side dark area, the offset direction of the second side is obtained. The offset direction of the second side is towards the center of the bonding area or away from the center of the bonding area.

[0037] Preferably, the step of extracting the maximum depth value or the average depth value of the surface contour based on the consistency between the first side offset direction and the second side offset direction includes:

[0038] When the first side offset direction is consistent with the second side offset direction, the difference between the lowest point height value and the normal coating height reference value in the abnormal contour area of ​​the bonding area surface in the non-penetrated state is extracted as the maximum depth value of the surface contour.

[0039] When the first side offset direction is opposite to the second side offset direction, extract the difference between all height values ​​in the abnormal contour area of ​​the bonding area surface in the non-penetrated state and the normal coating height reference value, calculate the arithmetic mean of the difference, and use the arithmetic mean as the average depth value of the surface contour.

[0040] Preferably, the step of extracting the surface contour depth value based on the consistency of the offset direction, comparing the surface contour depth value with the adjustable range of bonding pressure, and marking the process as unusable if it fails, and further calculating the bonding time extension amount and comparing it with the adjustable range of bonding time if it fails, and performing bonding pressure reduction and bonding time extension operations if it succeeds, and adjusting the laser scanning method to a high-resolution scanning mode to perform a re-scan of the abnormal area on the bonding area surface, includes:

[0041] Extract the maximum compressible depth corresponding to the upper limit of the adjustable range of bonding pressure;

[0042] If the maximum depth or average depth of the surface profile is greater than the maximum compressible depth, the bonding area is marked as unusable for the process.

[0043] If the maximum depth value or the average depth value of the surface profile is less than or equal to the maximum compressible depth, then the bonding pressure is reduced and the calculation of the bonding time extension continues.

[0044] Extract the longest bond time corresponding to the upper limit of the adjustable range of bond time.

[0045] Preferably, the longest bonding time corresponding to the upper limit of the adjustable range of extraction bonding time includes:

[0046] Multiply the maximum depth value of the surface profile by the bonding time compensation amount corresponding to the unit maximum depth to obtain the bonding time extension amount corresponding to the maximum depth;

[0047] Multiply the average depth value of the surface profile by the bonding time compensation amount corresponding to the unit average depth to obtain the bonding time extension amount corresponding to the average depth.

[0048] If the bonding time extension corresponding to the maximum depth or the bonding time extension corresponding to the average depth is greater than the longest bonding time, the bonding area is marked as unusable for the process.

[0049] If the bonding time extension corresponding to the maximum depth or the bonding time extension corresponding to the average depth is less than or equal to the longest bonding time, then based on the consistency between the first side offset direction and the second side offset direction, the corresponding bonding time extension amount is selected as the extension amount, and the bonding time is extended to adjust the laser scanning method to high-resolution scanning mode.

[0050] Preferably, a lead frame laser scanning and process availability determination system includes:

[0051] The surface contour position and offset vector calculation module is used to determine the center position of the dark area and the center position of the depression and to calculate the magnitude of the directional spatial offset vector.

[0052] The contour classification and penetration state determination module is used to determine the geometric type of surface anomaly contour based on the magnitude of the directional spatial offset vector, and to distinguish between the coating penetration state and the non-penetration state by combining the step interference modulation characteristic amplitude. The coating penetration state marking process is not available.

[0053] The non-penetrated contour depth extraction module is used to determine the offset direction on both sides of the abnormal contour of the non-penetrated bonding area surface, and extract the maximum depth value or the average depth value of the surface contour based on the consistency of the offset direction.

[0054] The process availability assessment and parameter adjustment module is used to compare the surface profile depth value with the adjustable range of bonding pressure. If it fails, the process is marked as unavailable. If it passes, the bonding time extension is calculated and compared with the adjustable range of bonding time. If it passes, the bonding pressure reduction operation, the bonding time extension operation, and the laser scanning method are adjusted to high-resolution scanning mode are executed.

[0055] Beneficial effects: This invention combines laser scanning reflection intensity images with three-dimensional topography images, uses the center of the dark area and the center of the depression to determine the directional spatial offset vector, thereby distinguishing between geometric and material-related surface anomalies. Furthermore, it uses the step interference modulation characteristic amplitude of the speckle intensity spatial sequence to identify the coating penetration state. For non-penetrated surface anomalies, the maximum or average depth of the contour is extracted by combining the consistency of the offset direction of both sides, and it is correlated with the adjustable range of bonding pressure and bonding time. Thus, based on optical contour measurement, it achieves accurate determination of the availability of bonding area processes, effectively overcoming the shortcomings of existing single threshold methods in microscale surface anomaly scenarios, which often result in misjudgment or omission. Attached Figure Description

[0056] Figure 1 This is a flowchart of the laser scanning and process availability determination method for the lead frame of the present invention;

[0057] Figure 2 This is a structural diagram of the laser scanning and process availability determination system for the lead frame of the present invention. Detailed Implementation

[0058] The present invention will now be described in detail with reference to the accompanying drawings.

[0059] Example 1: A method for laser scanning and process availability determination of lead frames, such as... Figure 1 As shown, it includes the following steps:

[0060] S1-1: Determine the center positions of the dark areas and depressions of the abnormal areas on the bonding region surface from the laser scanning reflection intensity image and the three-dimensional topography image, respectively, including:

[0061] In the reflection intensity image, extract the set of pixels below the preset intensity threshold in the abnormal area of ​​the bonding region surface; calculate the arithmetic mean of the horizontal and vertical coordinates of the pixel set respectively, and use them as the horizontal and vertical coordinates of the dark area center.

[0062] In the three-dimensional topography image, the set of height values ​​in the abnormal area of ​​the bonding zone surface is extracted; the set of height values ​​is fitted with a quadratic surface to obtain the fitted surface; the abscissa and ordinate of the lowest point of the fitted surface are extracted respectively as the abscissa and ordinate of the depression center.

[0063] It should be noted that this embodiment uses a laser measuring instrument to perform the following steps. The laser scanning reflection intensity image is generated by the detector in the laser measuring instrument acquiring the light intensity distribution in the specular reflection direction after the laser beam is projected onto the surface of the lead frame. The three-dimensional topography image is based on the principle of laser triangulation, reconstructing the surface contour from the height data.

[0064] During acquisition, the reflection intensity image and the 3D topography image are spatially registered using the same scanning coordinate system, resulting in a one-to-one correspondence between pixel positions in the two images. The surface anomaly regions of the bonding region in the 3D topography image utilize the spatial coordinate range corresponding to the set of pixels in the reflection intensity image that are below a preset intensity threshold, eliminating the need for independent segmentation of the bonding region surface anomaly regions in the 3D topography image.

[0065] The preset intensity threshold is set based on the lower limit of the statistical distribution of reflection intensity in the normal coating area. The preset intensity threshold is preferentially adopted by subtracting three times the standard deviation from the mean gray value of the normal area. If the calculated value is lower than 90% of the mean gray value of the normal area, then 90% of the mean is taken as the threshold to ensure that the threshold is non-negative and not too lenient. Pixels below the threshold are classified into the abnormal area of ​​the bonding area surface, thereby extracting the set of abnormal pixels on the bonding area surface.

[0066] The arithmetic mean of the x and y axes is calculated separately because the surface anomaly contour of the bonding zone is irregular and the reflection intensity distribution is uneven. The average value can stably characterize the center of the dark area. The x-axis corresponds to the laser scanning direction, and the y-axis corresponds to the vertical scanning direction. The height value set records the height information of each measurement point in the anomaly area of ​​the bonding zone surface, which is used to describe the morphology of the depression. The quadratic surface fitting approximates the height distribution using a quadratic polynomial with the least squares method. The purpose is to suppress measurement noise and local fluctuations caused by surface roughness, so that the lowest point of the fitted surface is closer to the actual depression center.

[0067] The x and y coordinates of the lowest point represent the position of the depression center in the horizontal and vertical directions, respectively. Together with the coordinates of the dark area center, they form the basis for calculating the directional spatial offset vector, thereby characterizing the spatial offset caused by the abnormal contour sidewall of the surface under specular reflection. This provides a key geometric basis for solving the problem that a single threshold is insufficient to distinguish the surface contour type of the bonding area, which leads to inaccurate process availability judgment.

[0068] S1-2: Calculate the magnitude of the directional spatial offset vector based on the center positions of the dark area and the depression, including:

[0069] Subtracting the x-coordinate of the dark area center from the x-coordinate of the depression center yields the x-component of the directional spatial offset vector.

[0070] Subtracting the ordinate of the dark area center from the ordinate of the depression center yields the ordinate component of the directional spatial offset vector.

[0071] The sum of squares of the directional spatial offset vector is obtained by adding the square of the horizontal component of the directional spatial offset vector to the square of the vertical component of the directional spatial offset vector.

[0072] The square root of the sum of squares of the directional spatial offset vectors is calculated to obtain the magnitude of the directional spatial offset vector.

[0073] It should be noted that the horizontal component of the directional spatial offset vector is obtained by subtracting the horizontal coordinate of the dark area center from the horizontal coordinate of the depression center, reflecting the offset distance of the surface anomaly contour depression position relative to the dark area center in the laser scanning direction. The vertical component is calculated in the same way, representing the offset distance in the vertical scanning direction.

[0074] Squaring the horizontal and vertical components separately eliminates the positive and negative effects of the coordinate difference, converting the offsets in both directions into non-negative distance contributions. The sum of the squares yields the sum of squares of the directional spatial offset vector, which characterizes the degree of deviation between the center of the dark area and the center of the depression in the two-dimensional plane.

[0075] The modulus length, obtained by taking the square root of the sum of squares, is the Euclidean distance between the center of the dark area and the center of the depression. This modulus quantifies the degree of spatial inconsistency caused by the sidewalls of abnormal surface profiles under specular reflection conditions. Existing technologies using a single threshold are insufficient to distinguish the surface profile type of the bonding region, leading to inaccurate process usability assessments. This modulus length provides a stable quantitative basis for subsequently distinguishing geometrically different types of abnormal surface profiles.

[0076] S2: Determine the geometric type of the abnormal profile on the bonding region surface based on the magnitude of the directional spatial offset vector, and distinguish between the coating penetration state and the non-penetration state by combining the step interference modulation characteristic amplitude. The coating penetration state is marked as unusable, and the non-penetration state proceeds to the subsequent adjustability evaluation, including:

[0077] When the magnitude of the directional spatial offset vector is higher than the preset directional offset threshold, the abnormal contour of the bonding area surface is determined to be of geometric type.

[0078] If it is a geometric type, then extract the height step and speckle intensity spatial sequence of the edge transition region in the abnormal contour of the bonding area surface respectively;

[0079] The height step is obtained as follows: In the three-dimensional topography image, along the direction perpendicular to the edge of the abnormal surface contour, the average height of the normal coating area on both sides of the edge is taken, and the difference between the two is taken as the height step. ;

[0080] The speckle intensity spatial sequence is extracted along a straight line passing through the center point of the surface anomaly contour and the nearest point on the edge, with a fixed sampling interval; when the edge of the surface anomaly contour is an irregular curve, it is extracted separately along the radial direction from the center point of the surface anomaly contour to each point on the edge and the arithmetic mean is taken.

[0081] The spatial spectrum is obtained by performing a Fourier transform on the spatial sequence of speckle intensity.

[0082] Based on height step Laser wavelength Angle of incidence and system space sampling reference length ,according to Calculate the expected spatial frequency f of the step interference modulation; where, The system spatial sampling reference length (e.g., an integer multiple of the laser spot diameter or scanning step size) is used to convert dimensionless ratios into spatial frequencies;

[0083] As a concrete quantitative realization of this ratio, under perpendicular incidence or a known angle of incidence... Under these conditions, the optical path difference of the reflected light caused by this stepped structure The ratio of optical path difference to laser wavelength. The expected frequency of the step interference modulation is determined, and then combined with the system's spatial sampling reference length. The expected spatial frequency of the step interference modulation is calculated according to the following formula: Those skilled in the art can determine the corresponding position of the expected frequency in the discrete spectrum based on the optical interference principle and the system's spatial sampling frequency, and then extract the interference modulation characteristic amplitude.

[0084] The amplitude at the expected spatial frequency in the spatial spectrum is taken as the characteristic amplitude of step interference modulation.

[0085] When the amplitude of the step interference modulation feature is higher than the preset step interference modulation amplitude threshold, the bonding area coating corresponding to the abnormal contour of the bonding area surface of the geometric type is determined to be in a penetrating state, and the bonding area is marked as unusable for the process.

[0086] When the amplitude of the step interference modulation feature is lower than the preset step interference modulation amplitude threshold, the bonding area coating corresponding to the abnormal surface profile of the bonding area of ​​the geometric type is determined to be in an unpenetrated state, and then proceeds to the subsequent adjustability evaluation.

[0087] When the magnitude of the directional spatial offset vector is lower than or equal to the preset directional offset threshold, the abnormal contour of the bonding area surface is determined to be a non-geometric material type, and the bonding area is directly marked as unusable for the process.

[0088] It should be noted that the magnitude of the directional spatial offset vector reflects the degree of spatial separation between the center of the dark area and the center of the depression. Under specular reflection conditions, geometrically typed surface anomalies have sidewalls, which deflect the reflected light away from the camera's receiving direction, thus misaligning the center of the dark area and the center of the depression. Non-geometric surface anomalies do not have sidewalls, and the center of the dark area and the center of the depression essentially coincide, resulting in a very small magnitude.

[0089] The preset directional offset threshold is obtained by statistically analyzing the modulus data of the normal coating area: the modulus data of the normal coating area is collected and its arithmetic mean is calculated. and standard deviation ,by As a preset directional offset threshold, a surface profile with a modulus exceeding this value is determined to have a geometric type with a sidewall structure.

[0090] The sidewalls of geometrically irregular surface profiles form height steps. Reflected light from both sides of these steps exhibits an optical path difference, which, along with the laser wavelength, determines the spatial frequency of the interference. The greater the step height, the greater the optical path difference, and the more significantly the amplitude at the corresponding frequency in the spatial spectrum is affected by interference modulation. The essential difference between the coated and non-coated states lies in the step height. In the coated-transparent state, the step height equals the coating thickness plus the depth of the surface irregular profile; in the non-transparent state, the step height is only the depth of the surface irregular profile. Therefore, the amplitude of the step interference modulation characteristics in the coated-transparent state is significantly higher than that in the non-transparent state.

[0091] The edge transition region is the pixel-connected area where the gray-level gradient amplitude on both sides of the abnormal surface contour edge exceeds a preset gradient threshold. If this region is too narrow, a strip of several pixels' width on both sides of the edge is taken as the edge transition region. The preset gradient threshold is set based on the statistical distribution of gray-level gradient at the boundary between the normal coating area and the defect area. The gray-level gradient amplitude at non-edge positions in the normal coating area is collected, and its arithmetic mean and standard deviation are calculated. The arithmetic mean and three times the standard deviation are used as the preset gradient threshold.

[0092] To suppress the interference of laser speckle noise on the determination of spectral amplitude, before performing Fourier transform on the spatial sequence of speckle intensity, a sliding window mean filter is first applied to the spatial sequence. The window width is determined according to the laser scanning sampling step size and should cover at least one speckle correlation length. The speckle correlation length is estimated by theoretical formula based on the laser wavelength, spot size and imaging system magnification, or obtained by experimental calibration through autocorrelation function, for example, by taking the width of several adjacent sampling points.

[0093] To improve the reliability of penetration determination, in addition to extracting the amplitude at the expected spatial frequency, the amplitude values ​​at the second harmonic (2f) and third harmonic (3f) of the expected spatial frequency are also extracted. When the amplitude at the expected spatial frequency f is higher than the preset threshold of the fundamental frequency, and the amplitudes at at least two frequencies of the second harmonic (2f) and third harmonic (3f) are higher than their respective preset thresholds, it is determined to be a coating penetration state. The preset thresholds corresponding to the second and third harmonics are obtained using the same statistical method as the fundamental frequency threshold, that is, the amplitude values ​​of qualified samples at the harmonic frequencies are collected respectively, and the arithmetic mean plus three times the standard deviation is taken as the harmonic threshold.

[0094] The preset interference modulation amplitude threshold is determined by statistical distribution analysis of the interference modulation characteristic amplitudes of known qualified coating samples and known penetrating coating samples: the fundamental frequency interference modulation characteristic amplitudes of qualified coating samples are collected, and their arithmetic mean is calculated. and standard deviation ,by This serves as the preset threshold for the fundamental frequency. Similarly, samples of the penetrated coating are collected to verify the classification effectiveness of this threshold. If the threshold is higher than this threshold, it indicates that the coating has penetrated, the underlying substrate is exposed, bonding is difficult to form an effective connection, and the marking process is unusable. If the threshold is lower than this threshold, it indicates that the coating is intact, and the abnormal surface contour is compensated by adjusting the bonding parameters, thus entering the adjustability evaluation.

[0095] When the magnitude of the directional spatial offset vector does not exceed the preset directional offset threshold, it indicates that the surface anomaly profile has no significant sidewall structure and is judged as a non-geometric surface anomaly such as oxide spots or organic contamination. Because this type of surface anomaly does not have resilient sidewalls that can be plastically deformed, it is difficult to eliminate interface contamination by adjusting the bonding parameters. Therefore, it is directly marked as unusable for the process and is not included in the subsequent adjustability evaluation.

[0096] S3-1: Determine the center position of the dark area, the center position of the depression, and the offset direction of the two sides of the abnormal contour area on the surface of the bonding region in the non-penetrated state, including:

[0097] Perform edge recognition on the abnormal contour area of ​​the bonding region surface in the non-penetrated state to obtain the first side edge on the side closer to the center of the bonding region and the second side edge on the side farther from the center of the bonding region.

[0098] The pixel with the lowest gray value in the first edge is taken as the center position of the first dark area;

[0099] The point with the lowest height value on the first side edge is taken as the center position of the first side depression;

[0100] By comparing the center position of the first side depression with the center position of the first side dark area, the offset direction of the first side is obtained. The offset direction of the first side is towards the center of the bonding area or away from the center of the bonding area.

[0101] The pixel with the lowest gray value in the second edge is taken as the center position of the dark area on the second side;

[0102] The point with the lowest height value on the second side edge is taken as the center position of the second side depression;

[0103] By comparing the center position of the second side depression with the center position of the second side dark area, the offset direction of the second side is obtained. The offset direction of the second side is towards the center of the bonding area or away from the center of the bonding area.

[0104] It should be noted that in this step, the abnormal contour region on the surface of the bonding area in the non-penetrated state refers to the abnormal region whose contour boundaries on both sides are extracted by the edge recognition operation after it has been determined to be in the non-penetrated state by S2. The abnormal contour region on the surface of the bonding area in the non-penetrated state has a gray-scale abrupt change compared to the normal coating area in the reflection intensity image. The edge recognition operation captures this abrupt boundary and separates the first side edge on the side closer to the center of the bonding area and the second side edge on the side farther from the center of the bonding area along the width direction of the bonding area strip. The two edges correspond to the two sidewalls on the abnormal contour of the surface, respectively.

[0105] The pixel with the lowest grayscale value on the first edge indicates the location where the reflected light is significantly weakened or deviates from the detector's receiving direction. The center of the first edge recess is determined by the point with the lowest height value, which corresponds to the measurement unit in the 3D topography image. Comparing the center of the first edge recess with the center of the first edge dark area, if the recess center is closer to the center of the bonding region than the dark area center, the first edge offset direction is towards the center of the bonding region; otherwise, it is away from the center. The second edge offset direction is obtained using the same logic.

[0106] The tilt orientation of the sidewalls directly describes the surface anomaly profile, whether they are towards or away from the center of the bonding region. If the center of the depression is closer to the center of the bonding region than the center of the dark area, it indicates that the sidewall is tilted inwards towards the bonding region, and the area of ​​reduced reflection is biased outwards. If the center of the depression is farther away from the center of the bonding region than the center of the dark area, it indicates that the sidewall is tilted outwards towards the bonding region, and the area of ​​reduced reflection is biased inwards.

[0107] If the offset directions on both sides are consistent, it indicates that the sidewalls of the surface anomaly profile tilt in the same direction, resulting in an asymmetrical concave shape. If the offset directions on both sides are opposite, it indicates that the sidewalls of the surface anomaly profile tilt in different directions, resulting in a symmetrical concave shape. This distinction determines whether to extract the maximum depth value or the average depth value of the surface profile. Asymmetrical concavities (consistent directions) require the maximum depth value to assess the worst location, while symmetrical concavities (opposite directions) require the average depth value to assess the overall impact. This overcomes the limitation of existing single threshold values, which are insufficient to represent the geometric features of the sidewalls of surface anomalies, leading to inaccurate process usability assessments.

[0108] S3-2: Based on the consistency between the first side offset direction and the second side offset direction, extract the maximum depth value or the average depth value of the surface contour, including:

[0109] When the first side offset direction is consistent with the second side offset direction, the difference between the lowest point height value and the normal coating height reference value in the abnormal contour area of ​​the bonding area surface in the non-penetrated state is extracted as the maximum depth value of the surface contour.

[0110] When the first side offset direction is opposite to the second side offset direction, extract the difference between all height values ​​in the abnormal contour area of ​​the bonding area surface in the non-penetrated state and the normal coating height reference value, calculate the arithmetic mean of the difference, and use the arithmetic mean as the average depth value of the surface contour.

[0111] It should be noted that the first side offset direction is the same as the second side offset direction, which means that the sidewalls on both sides of the abnormal surface profile of the unpenetrated bonding area are tilted in the same direction. The surface abnormal profile is asymmetrically concave. The lowest point height value corresponds to the deepest point on one side of the surface abnormal profile. The most dangerous position needs to be evaluated by the maximum depth value.

[0112] The first side offset direction being opposite to the second side offset direction indicates that the two sidewalls are tilted in different directions, and the abnormal surface profile is symmetrically concave. The arithmetic mean of all height values ​​should be used as the average depth value of the surface profile to assess the overall impact of the concave area.

[0113] The baseline value for normal coating height is the arithmetic mean of the heights of the normal coating areas surrounding the abnormal areas on the bonding zone surface. This distinction allows subsequent process availability assessments to select appropriate depth indicators based on the actual morphology of the abnormal surface contour, avoiding inaccurate judgments caused by a single threshold failing to reflect the geometric characteristics of the abnormal surface contour.

[0114] S4: Extract the surface profile depth value based on the consistency of the offset direction. Compare the surface profile depth value with the adjustable range of bonding pressure. If it fails, mark the process as unusable. If it succeeds, further calculate the bonding time extension and compare it with the adjustable range of bonding time. If it fails, mark the process as unusable. If it succeeds, perform bonding pressure reduction and bonding time extension operations, and adjust the laser scanning method to high-resolution scanning mode to perform a re-scan of abnormal areas on the bonding area surface, including:

[0115] Extract the maximum compressible depth corresponding to the upper limit of the adjustable range of bonding pressure;

[0116] If the maximum depth value or the average depth value of the surface profile is greater than the maximum compressible depth, the bonding area is marked as unusable for the process.

[0117] If the maximum depth value or the average depth value of the surface profile is less than or equal to the maximum compressible depth, then the bonding pressure is reduced and the calculation of the bonding time extension continues.

[0118] Extract the longest bond time corresponding to the upper limit of the adjustable range of bond time;

[0119] Multiply the maximum depth value of the surface profile by the bonding time compensation amount corresponding to the unit maximum depth to obtain the bonding time extension amount corresponding to the maximum depth;

[0120] Multiply the average depth value of the surface profile by the bonding time compensation amount corresponding to the unit average depth to obtain the bonding time extension amount corresponding to the average depth.

[0121] If the bonding time extension corresponding to the maximum depth or the bonding time extension corresponding to the average depth is greater than the longest bonding time, the bonding area is marked as unusable for the process.

[0122] The maximum bonding time is the maximum bonding time that the bonding equipment can output, which is determined by the equipment's hardware capabilities and process window. If the required extension of the bonding time exceeds this limit, the equipment will have difficulty providing enough energy input to allow the solder ball to complete plastic deformation and creep filling, and the abnormal surface contour will be difficult to close. Therefore, the bonding area in this case cannot be remedied by adjusting the bonding parameters and is marked as unusable for the process.

[0123] If the bonding time extension corresponding to the maximum depth or the bonding time extension corresponding to the average depth is less than or equal to the longest bonding time, then based on the consistency between the first side offset direction and the second side offset direction, the corresponding bonding time extension amount is selected as the extension amount, and the bonding time is extended to adjust the laser scanning method to high-resolution scanning mode.

[0124] It should be noted that the upper limit of the adjustable bonding pressure range is the maximum pressure that the wire bonding equipment is allowed to apply. The maximum flattenable depth corresponds to the maximum surface anomaly profile depth that the solder ball plastic deformation can flatten under this pressure. When the maximum surface profile depth or the average surface profile depth exceeds the maximum flattenable depth, the bonding pressure is insufficient to close the surface anomaly profile, leaving a gap at the bonding interface, and is therefore marked as unusable for the process.

[0125] When the surface profile depth is less than the maximum compressible depth, the value after reducing the bonding pressure is [value missing]. The pressure is reduced proportionally to the ratio of the defect depth to the maximum compressible depth, so that the applied bonding pressure matches the defect depth—the shallower the defect, the lower the required pressure; the deeper the defect (but not exceeding...). The greater the pressure required, the better. This avoids applying unnecessarily excessive pressure to shallow defects, preventing excessive deformation of the solder balls or microcracks in the chip substrate. To reduce the bonding pressure, The surface profile depth value is determined based on the consistency between the first side offset direction and the second side offset direction (the maximum surface profile depth value when the directions are consistent, and the average surface profile depth value when the directions are opposite). To the maximum compressible depth, This represents the upper limit of the adjustable bonding pressure range. The lower limit of the adjustable bonding pressure range is predetermined by the equipment specifications to ensure that the pressure is not too low, making effective bonding difficult. The calculated... The actual bonding pressure is output to the bonding equipment controller, which automatically reduces the pressure; or... The value is output to the display terminal for operators to manually set.

[0126] When the bonding pressure decreases, the mechanical work input to the solder ball per unit time decreases accordingly. The total energy required for the solder ball to flatten the abnormal surface contours is determined by the product of the pressure and the bonding time. To maintain a constant total energy and ensure that the solder ball has sufficient time to complete plastic deformation and creep filling, the bonding time needs to be extended while the pressure is reduced to compensate for the energy loss caused by the pressure reduction.

[0127] Bonding time extension according to Calculate, where, This is the amount of time extension for bonding. This represents the bonding time compensation per unit depth.

[0128] Pressure-time coupling compensation coefficient (0 < <1), calibration is performed using the following method: First, a standard surface anomaly profile is prepared for calibration; the standard surface anomaly profile is prepared by focused ion beam etching, laser etching, or indentation, and its depth is calibrated by a profilometer or confocal microscope. The depth measurement uncertainty should be less than the maximum compressible depth. 5%. Then, a sample with depth d0 is selected from the prepared standard surface anomaly profile, where d0 satisfies: Under pressure and within the default bonding time, the residual depth of the abnormal surface profile is greater than 0 but less than 0. 20% (i.e. It cannot be completely flattened under pressure, but it is close to closing. Using d0 respectively... and Bonding time extension tests were conducted at two pressure levels, and the minimum time extension required to close the abnormal surface profile was recorded at both pressure levels. and ;like =0, then increase d0 until >0, then recalibrate. (According to...) Obtained through calculation.

[0129] Maximum flattenable depth The calibration method is as follows: based on the upper limit of the adjustable range of the bonding pressure of the equipment. (Obtained directly from the device specification sheet) and default bond time To maintain consistent conditions, standard surface anomaly profiles of varying known depths were prepared on samples with the same plating specifications and solder ball material as the product under test. A pressing test was then conducted, and the surface anomaly profile depth at which the residual depth first decreased to zero was taken as the baseline. This value is a conservative baseline based on the default bond time.

[0130] Bonding time compensation Through calibration: After calibrating the maximum compressible depth, select multiple surface anomaly profile depths that are close to... Test samples of depth values, in accordance with Bonding time extension experiments were conducted under calculated pressure, and the minimum time extension required for closing the abnormal contours on the surface of each sample was recorded. A depth-extension curve was fitted, and its slope was taken as the bonding time compensation per unit depth. Its unit is seconds per micrometer (s / μm).

[0131] Combine the maximum depth value of the surface profile with Multiply by the product to obtain the bonding time extension corresponding to the maximum depth; then multiply the average depth value of the surface profile by... Multiplying these values ​​yields the bonding time extension corresponding to the average depth. Since the sidewalls of the depression tilt in the same direction when the directions are consistent, the depression is asymmetrical. During solder ball bonding, the stress on the sidewalls concentrates at the deepest point on one side. Therefore, the time compensation amount needs to be calculated based on the maximum depth to ensure closure at the worst-case location. When the directions are opposite, the depression is symmetrical with uniform stress distribution, and the overall closure requirement can be reflected using the average depth. Therefore, the corresponding bonding time extension amount needs to be selected as the actual extension amount based on the consistency of the first and second side offset directions. The selected bonding time extension amount is output to the bonding equipment controller, which automatically performs the time extension operation and verifies the closure status of the abnormal surface contour using a high-resolution scanning mode.

[0132] After adjusting the bonding parameters, a high-resolution scanning mode is used to perform a verification scan on the surface anomaly area to obtain a verification image and verify the effectiveness of the parameter adjustment. After the verification scan, the surface contour depth is extracted from the verification image. If the surface contour depth value is reduced to within the allowable range, it indicates that the depression has been effectively flattened, the surface anomaly contour has been closed, and the process-usable judgment result is output.

[0133] If the surface contour depth value does not decrease or even increases, it indicates that there was a deviation in the previous judgment of the abnormality type (geometric type, non-penetrating state) or that the parameter adjustment direction was incorrect. In this case, it cannot be directly determined that the process is unusable, because if the penetration state is judged incorrectly (actually penetrating but judged as non-penetrating), it will be difficult to close the depression with any parameter adjustment; if it is still in a non-penetrating state, it means that the depth of the depression exceeds the processing capacity of the current parameter combination, and a better pressure and time combination needs to be rematched within the adjustable range of the equipment.

[0134] Therefore, it is necessary to return to step S2 to re-classify the surface anomaly profile and determine the penetration status. If the re-determination indicates coating penetration, the process is directly marked as unusable; if it is still not penetrated, the reduction in bonding pressure and extension of bonding time are recalculated based on the re-verified depth value, and the result is verified again. This iterative process is repeated until the depression closes or the bonding parameters reach the adjustable range limit—if the depression still does not close after reaching the limit, it indicates that the anomaly has exceeded the equipment's capabilities, and the process is ultimately marked as unusable. This closed-loop mechanism ensures that process availability determination does not rely on a single detection result, but is verified through the actual parameter adjustment effect, thereby preventing misjudgments or omissions caused by a single threshold method and improving the reliability of the determination results.

[0135] The high-resolution scanning mode reduces the sampling step size of the laser scan to one-half or one-quarter of the original step size relative to the initial scanning mode, or switches to an imaging objective with a higher numerical aperture, in order to obtain a surface anomaly contour verification image with higher spatial resolution.

[0136] Furthermore, when the above method is applied to bonding devices of different models or under different calibration conditions, the upper limit of the adjustable bonding pressure range and the amount of bonding time compensation are... The device needs to be normalized and calibrated based on its actual output characteristics under the current calibration state to ensure that the process availability determination results are comparable across different devices.

[0137] Example 2: Based on Example 1, a lead frame laser scanning and process availability determination system, such as... Figure 2 As shown, it includes:

[0138] The surface contour position and offset vector calculation module is used to determine the center position of the dark area and the center position of the depression and to calculate the magnitude of the directional spatial offset vector.

[0139] The contour classification and penetration state determination module is used to determine the geometric type of surface anomaly contour based on the magnitude of the directional spatial offset vector, and to distinguish between the coating penetration state and the non-penetration state by combining the step interference modulation characteristic amplitude. The coating penetration state marking process is not available.

[0140] The non-penetrated contour depth extraction module is used to determine the offset direction on both sides of the abnormal contour of the non-penetrated bonding area surface, and extract the maximum depth value or the average depth value of the surface contour based on the consistency of the offset direction.

[0141] The process availability assessment and parameter adjustment module is used to compare the surface profile depth value with the adjustable range of bonding pressure. If it fails, the process is marked as unavailable. If it passes, the bonding time extension is calculated and compared with the adjustable range of bonding time. If it passes, the bonding pressure reduction operation, the bonding time extension operation, and the laser scanning method are adjusted to high-resolution scanning mode are executed.

[0142] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for laser scanning and process availability determination of lead frames, characterized in that, Includes the following steps: S1: Determine the center position of the dark area and the center position of the depression of the abnormal area on the surface of the bonding region from the laser scanning reflection intensity image and the three-dimensional topography image respectively, and calculate the magnitude of the directional spatial offset vector based on the center position of the dark area and the center position of the depression. S2: Determine the geometric type of the abnormal profile on the bonding area surface based on the magnitude of the directional spatial offset vector, and distinguish between the coating penetration state and the non-penetration state by combining the step interference modulation characteristic amplitude. The coating penetration state is marked as unusable, and the non-penetration state enters the subsequent adjustability evaluation. S3: Determine the center position of the dark area, the center position of the depression, and the offset direction on both sides of the abnormal contour area of ​​the bonding area in the non-penetrated state. Based on the consistency between the first side offset direction and the second side offset direction, extract the maximum depth value or the average depth value of the surface contour. S4: Extract the surface profile depth value based on the consistency of the offset direction, compare the surface profile depth value with the adjustable range of bonding pressure, if it fails, mark the process as unusable, if it passes, further calculate the bonding time extension amount and compare it with the adjustable range of bonding time, if it fails, mark the process as unusable, if it passes, perform the bonding pressure reduction operation and the bonding time extension operation, and adjust the laser scanning method to the high-resolution scanning mode to perform a re-scan of the abnormal area on the bonding area surface.

2. The method for laser scanning and process availability determination of lead frames according to claim 1, characterized in that, The step of determining the center positions of the dark areas and the center positions of the depressions in the abnormal areas on the bonding region surface from the laser scanning reflection intensity image and the three-dimensional topography image, respectively, includes: In the reflection intensity image, extract the set of pixels below the preset intensity threshold in the abnormal area of ​​the bonding region surface; calculate the arithmetic mean of the horizontal and vertical coordinates of the pixel set respectively, and use them as the horizontal and vertical coordinates of the dark area center. In the three-dimensional topography image, the set of height values ​​in the abnormal area of ​​the bonding zone surface is extracted; the set of height values ​​is fitted with a quadratic surface to obtain the fitted surface; the abscissa and ordinate of the lowest point of the fitted surface are extracted respectively as the abscissa and ordinate of the depression center.

3. The method for laser scanning and process availability determination of lead frames according to claim 1, characterized in that, The calculation of the magnitude of the directional spatial offset vector based on the center position of the dark area and the center position of the depression includes: Subtracting the x-coordinate of the dark area center from the x-coordinate of the depression center yields the x-component of the directional spatial offset vector. Subtracting the ordinate of the dark area center from the ordinate of the depression center yields the ordinate component of the directional spatial offset vector. The sum of squares of the directional spatial offset vector is obtained by adding the square of the horizontal component of the directional spatial offset vector to the square of the vertical component of the directional spatial offset vector. The square root of the sum of squares of the directional spatial offset vectors is calculated to obtain the magnitude of the directional spatial offset vector.

4. The method for laser scanning and process availability determination of lead frames according to claim 1, characterized in that, The geometric type of the abnormal profile on the bonding region surface is determined based on the magnitude of the directional spatial offset vector, and the penetration state and non-penetration state of the coating are distinguished by combining the amplitude of the step interference modulation characteristic. The coating penetration state is marked as unusable, and the non-penetration state enters the subsequent adjustability evaluation, including: When the magnitude of the directional spatial offset vector is higher than the preset directional offset threshold, the abnormal contour of the bonding area surface is determined to be of geometric type. If it is a geometric type, then extract the height step and speckle intensity spatial sequence of the edge transition region in the abnormal contour of the bonding area surface respectively; The spatial spectrum is obtained by performing a Fourier transform on the spatial sequence of speckle intensity. Based on height step Laser wavelength Angle of incidence and system space sampling reference length ,according to Calculate the expected spatial frequency f of the step interference modulation; The amplitude at the expected spatial frequency in the spatial spectrum is taken as the characteristic amplitude of step interference modulation. When the amplitude of the step interference modulation feature is higher than the preset step interference modulation amplitude threshold, the bonding area coating corresponding to the abnormal contour of the bonding area surface of the geometric type is determined to be in a penetrating state, and the bonding area is marked as unusable for the process. When the amplitude of the step interference modulation feature is lower than the preset step interference modulation amplitude threshold, the bonding area coating corresponding to the abnormal surface profile of the bonding area of ​​the geometric type is determined to be in an unpenetrated state, and then proceeds to the subsequent adjustability evaluation. When the magnitude of the directional spatial offset vector is lower than or equal to the preset directional offset threshold, the abnormal contour of the bonding area surface is determined to be a non-geometric material type, and the bonding area is directly marked as unusable for the process.

5. The method for laser scanning and process availability determination of lead frames according to claim 1, characterized in that, The determination of the center position of the dark area, the center position of the depression, and the offset direction of the two sides of the abnormal contour area on the surface of the bonding region in the non-penetrated state includes: Perform edge recognition on the abnormal contour area of ​​the bonding region surface in the non-penetrated state to obtain the first side edge on the side closer to the center of the bonding region and the second side edge on the side farther from the center of the bonding region. The pixel with the lowest gray value in the first edge is taken as the center position of the first dark area; The point with the lowest height value on the first side edge is taken as the center position of the first side depression; By comparing the center position of the first side depression with the center position of the first side dark area, the offset direction of the first side is obtained. The offset direction of the first side is towards the center of the bonding area or away from the center of the bonding area.

6. The method for laser scanning and process availability determination of lead frames according to claim 5, characterized in that, The determination of the center position of the dark area, the center position of the depression, and the offset direction of the two sides of the abnormal contour area on the surface of the bonding region in the non-penetrated state includes: The pixel with the lowest gray value in the second edge is taken as the center position of the dark area on the second side; The point with the lowest height value on the second side edge is taken as the center position of the second side depression; By comparing the center position of the second side depression with the center position of the second side dark area, the offset direction of the second side is obtained. The offset direction of the second side is towards the center of the bonding area or away from the center of the bonding area.

7. The method for laser scanning and process availability determination of lead frames according to claim 1, characterized in that, The step of extracting the maximum depth value or the average depth value of the surface contour based on the consistency between the first side offset direction and the second side offset direction includes: When the first side offset direction is consistent with the second side offset direction, the difference between the lowest point height value and the normal coating height reference value in the abnormal contour area of ​​the bonding area surface in the non-penetrated state is extracted as the maximum depth value of the surface contour. When the first side offset direction is opposite to the second side offset direction, extract the difference between all height values ​​in the abnormal contour area of ​​the bonding area surface in the non-penetrated state and the normal coating height reference value, calculate the arithmetic mean of the difference, and use the arithmetic mean as the average depth value of the surface contour.

8. The method for laser scanning and process availability determination of lead frames according to claim 1, characterized in that, The process involves extracting the surface contour depth value based on the consistency of the offset direction, comparing the surface contour depth value with the adjustable range of bonding pressure, and marking the process as unusable if the comparison fails. If the comparison succeeds, the bonding time extension is further calculated and compared with the adjustable range of bonding time. If the comparison fails, the process is marked as unusable; if the comparison succeeds, the bonding pressure reduction operation and bonding time extension operation are performed. The laser scanning method is then adjusted to a high-resolution scanning mode to perform a re-scan of abnormal areas on the bonding region surface, including: Extract the maximum compressible depth corresponding to the upper limit of the adjustable range of bonding pressure; If the maximum depth or average depth of the surface profile is greater than the maximum compressible depth, the bonding area is marked as unusable for the process. If the maximum depth value or the average depth value of the surface profile is less than or equal to the maximum compressible depth, then the bonding pressure is reduced and the calculation of the bonding time extension continues. Extract the longest bond time corresponding to the upper limit of the adjustable range of bond time.

9. The method for laser scanning and process availability determination of lead frames according to claim 8, characterized in that, The maximum bond time corresponding to the upper limit of the adjustable range of extraction bond time includes: Multiply the maximum depth value of the surface profile by the bonding time compensation amount corresponding to the unit maximum depth to obtain the bonding time extension amount corresponding to the maximum depth; Multiply the average depth value of the surface profile by the bonding time compensation amount corresponding to the unit average depth to obtain the bonding time extension amount corresponding to the average depth. If the bonding time extension corresponding to the maximum depth or the bonding time extension corresponding to the average depth is greater than the longest bonding time, the bonding area is marked as unusable for the process. If the bonding time extension corresponding to the maximum depth or the bonding time extension corresponding to the average depth is less than or equal to the longest bonding time, then based on the consistency between the first side offset direction and the second side offset direction, the corresponding bonding time extension amount is selected as the extension amount, and the bonding time is extended to adjust the laser scanning method to high-resolution scanning mode.

10. A leadframe laser scanning and process availability determination system, used to implement the leadframe laser scanning and process availability determination method according to any one of claims 1-9, characterized in that, include: The surface contour position and offset vector calculation module is used to determine the center position of the dark area and the center position of the depression and to calculate the magnitude of the directional spatial offset vector. The contour classification and penetration state determination module is used to determine the geometric type of surface anomaly contour based on the magnitude of the directional spatial offset vector, and to distinguish between the coating penetration state and the non-penetration state by combining the step interference modulation characteristic amplitude. The coating penetration state marking process is not available. The non-penetrated contour depth extraction module is used to determine the offset direction on both sides of the abnormal contour of the non-penetrated bonding area surface, and extract the maximum depth value or the average depth value of the surface contour based on the consistency of the offset direction. The process availability assessment and parameter adjustment module is used to compare the surface profile depth value with the adjustable range of bonding pressure. If it fails, the process is marked as unavailable. If it passes, the bonding time extension is calculated and compared with the adjustable range of bonding time. If it passes, the bonding pressure reduction operation, the bonding time extension operation, and the laser scanning method are adjusted to high-resolution scanning mode are executed.

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