A method for edge emitting laser bar thermal stress package compensation

Abstract

The application discloses an edge-emitting laser BAR strip thermal stress packaging compensation method, and relates to the technical field of semiconductor laser packaging manufacturing, which comprises the following steps: arranging packaging data in time sequence to obtain packaging time sequence data; extracting solder solidification time and welding pressure release time, and performing interval interception on the packaging time sequence data to obtain solidification pressure maintaining data; determining a cooling period according to the solidification pressure maintaining data, and identifying the change state of warping records to obtain cooling warping data; performing shrinkage transmission determination on the cooling warping data according to heat sink material data and solder layer data to obtain shrinkage transmission data; determining the effect of pressure maintaining on warping after solder solidification according to the solidification pressure maintaining data and the shrinkage transmission data to obtain pressure maintaining effect data; and compensating and adjusting the welding pressure or welding temperature curve according to the pressure maintaining effect data to obtain packaging stress compensation results; and the application improves the accuracy of compensation and adjustment in the packaging process of the edge-emitting laser BAR strip.

Description

Technical Field

[0001] This application relates to the field of semiconductor laser packaging and manufacturing technology, and more specifically, to a method for compensating for thermal stress in edge-emitting laser BAR strips during packaging. Background Technology

[0002] In the manufacturing process of edge-emitting laser bar (EBRD) packages, the EBRD is an edge-emitting laser bar array, formed by arranging multiple edge-emitting semiconductor laser emitting units along the length of a bar chip. Each edge-emitting semiconductor laser emitting unit emits laser light from the end face of the bar chip. The EBRD is typically soldered to a heat sink via a solder layer to form a mechanical support structure and a heat conduction path. The packaging state between the EBRD, the solder layer, and the heat sink affects the uniformity of the solder interface, the thermal conductivity of the package structure, and the morphology retention of the EBRD. Especially under high-power operating conditions, residual thermal stress and warpage deformation formed during the packaging process can adversely affect the device's output consistency and long-term operational reliability.

[0003] Existing edge-emitting laser bar (EFLAP) packaging processes typically employ a preset welding pressure and temperature profile. Through pressure application and temperature control, the solder layer undergoes sequential melting, spreading, solidification, and cooling to complete the connection between the EFLAP bar and the heat sink. Regarding thermal stress control in packaging, existing technologies can further improve packaging quality through heat sink material selection, solder material adjustment, solder layer structure optimization, improved clamping methods, or post-soldering warpage detection. However, current approaches generally focus on packaging material selection, overall process parameter setting, or post-soldering result evaluation, lacking analytical data that matches the actual packaging process regarding the thermal stress transfer state during the period from solder solidification to the release of welding pressure.

[0004] After the solder layer solidifies, a fixed connection is formed between the edge-emitting laser bar (EFLAP) strip, the solder layer, and the heat sink. As cooling continues, the heat sink will still experience a shrinkage response. This shrinkage may be transmitted through the solder layer to the EFLAP strip, causing changes in its warpage. When there are differences in the material's thermal deformation characteristics, interface bonding state, and the evolution of thermal stress after solidification, the direction and extent of the effect of continuous pressure holding after solder solidification on the warpage of the EFLAP strip may also differ. Current technologies typically execute the welding pressure holding method, pressure release timing, and cooling control process as preset process conditions. It is difficult to identify whether continuous pressure holding in the current packaging state suppresses or amplifies warpage, easily leading to a mismatch between pressure holding control and the evolution of thermal stress. This can result in insufficient post-soldering warpage control, uneven welding interface adhesion, reduced local heat conduction capacity, and decreased packaging consistency, making it difficult to meet the requirements of precise thermal stress control and packaging reliability in EFLAP strip packaging manufacturing.

[0005] In view of this, this application proposes a thermal stress packaging compensation method for edge-emitting laser BAR strips to solve the above problems. Summary of the Invention

[0006] To address the problem of insufficient thermal stress compensation during the packaging process of edge-emitting laser bar strips, this application provides the following technical solution: a method for thermal stress compensation during the packaging of edge-emitting laser bar strips, comprising:

[0007] The packaging data of the edge-emitting laser bar is obtained. The packaging data includes heat sink material data, solder layer data, welding temperature record, welding pressure record, and edge-emitting laser bar warpage record. The packaging data is then processed to obtain packaging timing data.

[0008] Solder solidification time and welding pressure release time are extracted from the packaging timing data. The packaging timing data is then truncated in intervals, with solder solidification time as the start time and welding pressure release time as the end time, to obtain solidification and holding pressure data.

[0009] The cooling period is determined based on the welding temperature record in the solidification and pressure holding data, and the change state of the edge-emitting laser BAR strip warping record during the cooling period is identified to obtain the cooling warping data.

[0010] Based on the heat sink material data and solder layer data in the packaging data, shrinkage transfer is determined by the cooling warp data to obtain shrinkage transfer data.

[0011] Based on solidification and pressure holding data and shrinkage transfer data, the effect of pressure holding on the warping of the laser-emitting BAR stripe on the opposite side after solder solidification is determined, and pressure holding effect data is obtained.

[0012] Based on the pressure holding data, the welding pressure or welding temperature curves during the edge-emitting laser BAR strip packaging process are compensated and adjusted to obtain the packaging stress compensation results.

[0013] Furthermore, the method for obtaining the cooling warp data includes:

[0014] Compare the welding temperature records that are adjacent in time sequence in the solidification and holding pressure data. The time period between adjacent records where the welding temperature in the later welding temperature record is lower than the welding temperature in the earlier welding temperature record is determined as the cooling acquisition segment. Then, merge the adjacent cooling acquisition segments to obtain the cooling period.

[0015] The warping direction of the edge-emitting laser BAR strip warping record during the cooling period is extracted, and the warping direction is arranged in chronological order to obtain the warping direction sequence.

[0016] The warping direction sequence is identified to obtain the warping change state of the edge-emitting laser BAR strips corresponding to each cooling period.

[0017] Record the cooling period, the reference warp direction, the welding temperature change corresponding to each cooling period, the warp direction sequence, and the warp change state of the edge-emitting laser BAR strip corresponding to each cooling period to obtain cooling warp data.

[0018] Furthermore, the method for obtaining the warping direction sequence includes:

[0019] From the edge-emitting laser bar warpage records in the solidification and holding pressure data, the edge-emitting laser bar warpage direction corresponding to the solder solidification time is extracted as the reference warpage direction, and the edge-emitting laser bar warpage direction and edge-emitting laser bar warpage amount during the cooling period are extracted.

[0020] The warping direction of the edge-emitting laser bar is compared with the reference warping direction, and the warping amount of the edge-emitting laser bar is uniformly processed according to the reference direction based on the comparison results to obtain the direction-normalized warping amount.

[0021] The absolute value of the difference in normalized warpage in adjacent time-series directions is calculated to obtain the magnitude of the change.

[0022] If the change is less than the preset effective warping change threshold, the warping change direction will be determined as no effective change.

[0023] If the change amplitude is greater than or equal to the preset effective warping change threshold, the warping change direction that increases or decreases along the reference warping direction is determined based on the relationship between the normalized warping amount in the latter direction and the normalized warping amount in the former direction.

[0024] Arrange the warping directions in chronological order to obtain a warping direction sequence.

[0025] Furthermore, the method for obtaining the shrinkage transfer data includes:

[0026] Extract the welding temperature change, warping direction sequence, and warping change state of the edge-emitting laser BAR strip corresponding to each cooling period from the cooling warping data, and extract the thermal expansion coefficient of the heat sink material from the heat sink material data.

[0027] Based on the thermal expansion coefficient of the heat sink material, the change in welding temperature, the solder layer data, and the warping direction sequence, the shrinkage transfer quantitative calculation is performed for each cooling period to obtain the shrinkage transfer judgment quantity corresponding to each cooling period.

[0028] Based on the warping change state of the edge-emitting laser BAR strips corresponding to each cooling period, the transmission direction and effective transmission are determined for each cooling period, and the shrinkage transmission determination results for each cooling period are obtained.

[0029] Record the contraction transfer determination results and contraction transfer determination quantities corresponding to each cooling period to obtain contraction transfer data.

[0030] Furthermore, the method for obtaining the contraction transfer determination quantity corresponding to each cooling period includes:

[0031] The product of the thermal expansion coefficient of the heat sink material and the welding temperature change corresponding to each cooling period is calculated to obtain the degree of heat sink cooling shrinkage during each cooling period.

[0032] Thickness deviation and thickness dispersion calculations are performed on the solder layer data to obtain the average thickness deviation rate and the thickness dispersion of the solder layer; the average thickness deviation rate and the thickness dispersion of the solder layer are weighted and summed, and the reciprocal of the weighted sum is taken to obtain the solder layer transfer coefficient.

[0033] The reference warp direction is extracted from the cooling warp data. The warp direction sequence corresponding to each cooling period is statistically analyzed to obtain the number of records that increase along the reference warp direction and the number of records that decrease along the reference warp direction for each cooling period. The difference between the number of records of the two types and the sum of the numbers within the same cooling period are calculated to obtain the warp transmission direction coefficient corresponding to each cooling period.

[0034] The absolute values ​​of the heat sink shrinkage degree, solder layer transfer coefficient, and warpage transfer direction coefficient corresponding to each cooling period are multiplied to obtain the shrinkage transfer judgment quantity corresponding to each cooling period.

[0035] Furthermore, the method for obtaining the pressure-holding data includes:

[0036] Extract the solder solidification time, welding pressure release time and welding pressure record from the solidification and pressure holding data, and determine the pressure holding period with the solder solidification time as the start time and the welding pressure release time as the end time;

[0037] During the pressure holding period, the welding pressure record is truncated according to each cooling period, and the truncated welding pressure record is divided into adjacent acquisition segments to obtain the set of adjacent acquisition segments corresponding to each cooling period.

[0038] Based on the set of adjacent acquisition segments corresponding to each cooling period and the contraction transmission judgment quantity corresponding to each cooling period, the pressure holding effect is quantitatively calculated for each cooling period to obtain the pressure holding effect judgment quantity corresponding to each cooling period.

[0039] Based on the shrinkage transfer judgment results, the pressure holding effect judgment quantity, and the pressure holding effect benchmark threshold corresponding to each cooling period, the pressure holding effect is judged for each cooling period, and the pressure holding effect judgment results corresponding to each cooling period are obtained. The pressure holding effect judgment quantity, pressure holding effect benchmark threshold, and pressure holding effect judgment results corresponding to each cooling period are recorded to obtain the pressure holding effect data.

[0040] Furthermore, the method for obtaining the pressure holding effect determination quantity corresponding to each cooling period includes:

[0041] The welding pressure corresponding to the solidification time of the solder is extracted from the welding pressure record to obtain the reference holding pressure.

[0042] Read the welding pressure at both ends of each adjacent acquisition segment in the set of adjacent acquisition segments corresponding to each cooling period, and determine the minimum value of the welding pressure at both ends as the interval holding pressure;

[0043] The ratio of the pressure maintained in each interval to the benchmark pressure is calculated, and the ratios of adjacent sampling segments within the same cooling period are averaged to obtain the pressure maintenance degree for each cooling period.

[0044] The pressure holding effect judgment quantity for each cooling period is obtained by multiplying the pressure holding degree for each cooling period with the contraction transmission judgment quantity for each cooling period.

[0045] Furthermore, the method for obtaining the packaging stress compensation result includes:

[0046] Extract the pressure holding effect judgment result, pressure holding effect judgment quantity and pressure holding effect benchmark threshold corresponding to each cooling period from the pressure holding effect data, and determine the cooling period with insufficient pressure holding effect as the cooling period to be compensated.

[0047] Subtract the corresponding pressure holding effect judgment quantity from the pressure holding effect benchmark threshold corresponding to the cooling period to be compensated, and calculate the ratio of the difference to the pressure holding effect benchmark threshold to obtain the pressure holding effect gap ratio;

[0048] Based on the shrinkage transmission judgment result corresponding to the cooling period to be compensated, the compensation adjustment object is determined, and the compensation adjustment object is the welding pressure or welding temperature curve.

[0049] Based on the pressure holding gap ratio, the compensation adjustment object is adjusted to obtain the welding pressure compensation content or welding temperature curve compensation content.

[0050] Record the cooling period to be compensated, the object to be compensated, the proportion of the pressure holding gap, and the welding pressure compensation content or welding temperature curve compensation content corresponding to the object to be compensated, to obtain the encapsulation stress compensation result.

[0051] Furthermore, the method for determining the compensation adjustment object includes:

[0052] Extract the baseline warp direction from the cooling warp data and read the contraction transfer determination result corresponding to the cooling period to be compensated;

[0053] When the shrinkage transfer determination result is that it is transferred along the reference warping direction or deviates from the reference warping direction, the welding pressure is determined as the compensation and adjustment object.

[0054] When the shrinkage transfer determination result indicates that the transfer direction is unstable, the welding temperature curve is determined as the object of compensation and adjustment.

[0055] Furthermore, the method for obtaining the welding temperature curve compensation content includes:

[0056] Obtain the welding temperature curve control data corresponding to the cooling period to be compensated, and extract the start control time of the cooling period, the original cooling duration, and the control time of each intermediate control node.

[0057] Based on the pressure holding gap ratio, the original cooling time is extended to obtain the compensated cooling time; and the compensated cooling time is added to the starting control time of the cooling period to obtain the compensated termination control time.

[0058] Calculate the time difference between the control time of each intermediate control node and the start control time of the cooling period, and calculate the ratio of the time difference to the original cooling duration to obtain the time ratio of each intermediate control node; based on the time ratio, map each intermediate control node to the compensated cooling duration to obtain the control time of each compensated node.

[0059] Based on the termination control time and control time of each node after compensation, the termination control time of the cooling period and the control time of each intermediate control node in the welding temperature curve control data are updated to obtain the welding temperature curve compensation content.

[0060] Compared with the prior art, the technical effects and advantages of the edge-emitting laser BAR strip thermal stress packaging compensation method of this application are as follows:

[0061] This application focuses on the encapsulation stage from solder solidification to the release of welding pressure. It organizes the encapsulation data of the edge-emitting laser bar (EBRD) strip into time-series data, generating solidification and pressure holding data and temperature-induced warpage data. This allows the temperature and warpage changes during the solidification and pressure holding stage to be analyzed on a unified time-series basis. Consequently, subsequent judgments can be directly applied to the actual pressure holding stage after solder solidification, providing a data foundation for identifying the relationship between continuous pressure holding and the warpage changes of the EBRD strip.

[0062] In the analysis of thermal stress action chains, heat sink material data, solder layer data, and cooling warpage data are used to determine the shrinkage transmission during the cooling process. Solidification pressure holding data is then used to determine the effect of pressure holding after solder solidification on the warpage of the edge-emitting laser bar (EFLEB) strip, thus forming pressure holding effect data. Compared to existing technologies that mainly rely on fixed process conditions or post-soldering result evaluation, this application incorporates heat sink shrinkage, solder layer transmission, and post-solidification pressure holding effect into a continuous judgment process. This reduces the mismatch between pressure holding control and thermal stress changes, improving the relevance and reliability of thermal stress analysis for EFLEB packaging.

[0063] The pressure holding data is further used to determine the direction of compensation adjustment for the welding pressure or welding temperature profile, and to generate encapsulation stress compensation results, enabling the preliminary judgment results to be transformed into a basis for subsequent encapsulation process correction. For the cooling period when the pressure holding effect is insufficient, compensation content adapted to the current encapsulation state can be further generated, which is beneficial to improving problems such as insufficient post-solder warpage control, uneven welding interface adhesion, and decreased local heat conduction capacity, thereby enhancing the consistency and controllability of the edge-emitting laser bar packaging process.

[0064] In summary, this application continuously connects the extraction of solidification and pressure holding stage, identification of cooling warpage, determination of shrinkage transfer, determination of pressure holding effect, and compensation adjustment output, so that it can clearly determine whether the continuous pressure holding is suitable for the current packaging state, and form a packaging stress compensation result that can be used for subsequent packaging process correction, thereby improving the targeting of thermal stress control, packaging consistency, and the basis for process adjustment in the edge-emitting laser BAR strip packaging process. Attached Figure Description

[0065] Figure 1This is a flowchart illustrating a thermal stress packaging compensation method for an edge-emitting laser bar strip according to an embodiment of this application.

[0066] Figure 2 This is a packaging process application scenario diagram of a thermal stress packaging compensation method for an edge-emitting laser BAR strip according to an embodiment of this application;

[0067] Figure 3 This is a flowchart illustrating the generation of the warp direction sequence according to an embodiment of this application. Detailed Implementation

[0068] The technical solutions of this application will be described in detail, clearly, and completely below with reference to the accompanying drawings of the embodiments. It should be particularly noted that the specific embodiments described below are only used to better illustrate and explain the technical solutions of this application, and are intended to enable those skilled in the art to better understand and implement this application, and should not be construed as limiting the scope of protection of this application. Without departing from the spirit and substance of this application, those skilled in the art can modify, adjust, or make equivalent substitutions based on the content disclosed in this application, and these modifications, adjustments, or equivalent substitutions should all be considered within the scope of protection of this application.

[0069] In some embodiments, the edge-emitting laser bar remains under welding pressure after the solder solidifies and continues to cool along with the heat sink and solder layer. Warping changes occurring in the edge-emitting laser bar during this stage may be caused by the shrinkage of the heat sink and solder layer transmitted through the welding interface, or may be limited, maintained, or exacerbated by the continued pressure maintained after solder solidification.

[0070] Based solely on the warpage of the edge-emitting laser bar at the end of the encapsulation process, it is difficult to distinguish the different effects of material shrinkage transfer and post-soldering pressure holding on warpage changes. For example, a small amount of warpage detected at the end of the encapsulation process could be due to a low degree of shrinkage transfer from the heat sink and solder layer, or it could be due to the suppression of cooling warpage by continuous pressure holding. A large amount of warpage detected at the end of the encapsulation process could be due to the continuous transfer of material shrinkage differences, or it could be related to a mismatch in the pressure holding method after solder solidification.

[0071] Therefore, please refer to Figure 1 and Figure 2 This embodiment provides a method for compensating for thermal stress in the packaging of an edge-emitting laser bar strip, including:

[0072] S1: Obtain the packaging data of the edge-emitting laser bar. The packaging data includes heat sink material data, solder layer data, welding temperature record, welding pressure record, and edge-emitting laser bar warpage record. Perform timing processing on the packaging data to obtain packaging timing data.

[0073] Furthermore, methods for obtaining encapsulated timing data include:

[0074] S11: Obtain the encapsulation data of the edge-emitting laser bar.

[0075] In specific implementation, the following data are obtained: heat sink material data, solder layer data, welding temperature record, welding pressure record, and edge-emitting laser bar warpage record, to obtain packaging data. The heat sink material data is obtained from heat sink material batch documents or heat sink material testing records, and includes the coefficient of thermal expansion of the heat sink material. The solder layer data is obtained from solder layer thickness testing records, and includes the measured solder layer thickness. The welding temperature record is obtained from the temperature acquisition unit of the welding equipment, and includes the acquisition time and welding temperature. The welding pressure record is obtained from the pressure acquisition unit of the welding equipment, and includes the acquisition time and welding pressure. The edge-emitting laser bar warpage record is obtained from a warpage measurement device, and includes the acquisition time, edge-emitting laser bar warpage amount, and edge-emitting laser bar warpage direction.

[0076] S12: Use the encapsulation task identifier to collect the encapsulated data.

[0077] In practice, the packaging task of a single edge-emitting laser bar is used as the data collection unit. The packaging task identifier is used to collect the heat sink material data, solder layer data, welding temperature record, welding pressure record, and edge-emitting laser bar warpage record under the same packaging task. The packaging task identifier is a number that can uniquely identify the packaging task of a single edge-emitting laser bar. The heat sink material data and solder layer data are classified into the same packaging task according to the packaging task identifier, and the welding temperature record, welding pressure record, and edge-emitting laser bar warpage record are entered into the subsequent timing processing process according to the packaging task identifier.

[0078] S13: Using the unified clock of the welding equipment as the time reference, the acquisition time of welding temperature records, welding pressure records, and edge-emitting laser BAR strip warping records is uniformly organized.

[0079] In practice, the welding temperature record, welding pressure record, and edge-emitting laser bar warpage record under the same packaging task identifier are read. The unified clock of the welding equipment is used as the time reference. The acquisition time in the welding temperature record, welding pressure record, and edge-emitting laser bar warpage record is converted into the acquisition time under the unified clock of the welding equipment, so that the welding temperature, welding pressure, and edge-emitting laser bar warpage can participate in subsequent timing matching under the same time reference.

[0080] S14: Based on the unified and organized acquisition time, perform time-series matching on the welding temperature record, welding pressure record, and edge-emitting laser BAR strip warping record to form a unified acquisition time sequence.

[0081] In practice, when the sampling periods and acquisition times of the welding temperature record, welding pressure record, and edge-emitting laser bar warpage record are consistent, the welding temperature, welding pressure, edge-emitting laser bar warpage amount, and edge-emitting laser bar warpage direction under the same acquisition time are organized into the same time sequence record according to the acquisition time order, and the same acquisition time is arranged in chronological order to form a unified acquisition time sequence.

[0082] When the sampling periods of the welding temperature record, welding pressure record, and edge-emitting laser bar warp record are inconsistent, or the sampling periods are consistent but the acquisition times are different, the overlapping portion of the acquisition time ranges of the welding temperature record, welding pressure record, and edge-emitting laser bar warp record is extracted to obtain a common acquisition time range; the sampling periods of the welding temperature record, welding pressure record, and edge-emitting laser bar warp record are compared, and the largest sampling period among the three types of records is determined as the unified sampling period; starting from the start time of the common acquisition time range, a set of acquisition time points to be judged is generated point by point according to the unified sampling period; for each acquisition time point to be judged, the sampling periods of the welding temperature record, welding pressure record, and edge-emitting laser bar warp record are respectively... The records select the acquisition values ​​whose acquisition time is closest to the acquisition time point to be judged. When the acquisition times corresponding to the selected welding temperature, welding pressure, and edge-emitting laser bar warpage are all within the acquisition time matching window, the acquisition time point to be judged is determined as the unified acquisition time point, and the selected welding temperature, welding pressure, edge-emitting laser bar warpage, and edge-emitting laser bar warpage direction are organized into the same time sequence record. When any one of the acquisition values ​​of welding temperature, welding pressure, or edge-emitting laser bar warpage is missing in the acquisition time matching window, the acquisition time point to be judged is not determined as the unified acquisition time point. The determined unified acquisition time points are arranged in chronological order to form a unified acquisition time sequence.

[0083] The acquisition time matching window is centered on the acquisition time point to be judged, and the lengths on both sides of the window are determined according to half of the unified sampling period. The maximum sampling period is determined as the unified sampling period, and the acquisition time matching window is set according to the unified sampling period to avoid the same acquisition value in the record with the sampling period equal to the maximum sampling period being repeatedly matched to multiple adjacent time series records.

[0084] S15: Generate encapsulated time series data based on the aggregated encapsulated data and the unified collection time series.

[0085] In practice, the welding temperature records, welding pressure records, and edge-emission laser bar warpage records, arranged according to a unified acquisition time sequence, are combined with the heat sink material data and solder layer data belonging to the same packaging task according to the packaging task identifier to obtain packaging time sequence data. The packaging time sequence data includes the packaging task identifier, the unified acquisition time sequence, the welding temperature records, welding pressure records, and edge-emission laser bar warpage records arranged according to the unified acquisition time sequence, and the heat sink material data and solder layer data belonging to the same packaging task according to the packaging task identifier. The packaging time sequence data is used in S2 to extract the solder solidification time and the welding pressure release time.

[0086] S2: Extract the solder solidification time and welding pressure release time from the packaging timing data, and use the solder solidification time as the start time and the welding pressure release time as the end time to perform interval extraction on the packaging timing data to obtain solidification and pressure holding data.

[0087] Furthermore, methods for obtaining solidification pressure holding data include:

[0088] S21: Extract solder solidification time from the soldering temperature record in the packaging timing data.

[0089] In practice, the soldering temperature record in the packaging timing data is read, and the solder solidification time is extracted based on the solder solidification judgment temperature. The solder solidification judgment temperature is determined according to the solidus temperature in the solder material file. When the solder material file records the solder solidification characteristics in terms of solidification temperature range, the lower limit temperature of the solidification temperature range is determined as the solder solidification judgment temperature. The soldering temperature record is read according to the unified acquisition time sequence. When the soldering temperature changes from being greater than the solder solidification judgment temperature to being less than or equal to the solder solidification judgment temperature, the acquisition time when the soldering temperature is first less than or equal to the solder solidification judgment temperature is determined as the solder solidification time.

[0090] S22: Extract the welding pressure release time from the welding pressure record in the packaging timing data based on the solder solidification time.

[0091] In practice, welding pressure records with acquisition times greater than or equal to solder solidification time are read, and welding pressure release time is extracted based on pressure release judgment value. Pressure release judgment value is determined based on pressure release control value recorded in packaging process document or welding equipment pressure control document. Welding pressure records with acquisition times greater than or equal to solder solidification time are read according to unified acquisition time sequence, and the acquisition time when the welding pressure is first less than or equal to pressure release judgment value is determined as welding pressure release time.

[0092] S23: Using the solder solidification time as the start time and the welding pressure release time as the end time, the packaging timing data is truncated in intervals to obtain solidification and pressure holding data.

[0093] In practice, welding temperature records, welding pressure records, and edge-emitting laser bar warpage records with acquisition times greater than or equal to the solder solidification time and less than or equal to the welding pressure release time are extracted from the packaging timing data. The extracted welding temperature records, welding pressure records, and edge-emitting laser bar warpage records are then organized according to a unified acquisition time sequence to obtain solidification and pressure holding data. The solidification and pressure holding data includes the solder solidification time, the welding pressure release time, and the welding temperature records, welding pressure records, and edge-emitting laser bar warpage records between the solder solidification time and the welding pressure release time.

[0094] The solidification and pressure holding data corresponds to the solidification and pressure holding stage from the time the solder solidifies to the time the welding pressure is released. The solidification and pressure holding data is used to identify the cooling process and the warping changes of the edge-emitting laser BAR strip during the solidification and pressure holding stage, and to generate cooling warping data.

[0095] S3: Determine the cooling period based on the welding temperature record in the solidification and pressure holding data, and identify the change state of the edge-emitting laser BAR strip warping record during the cooling period to obtain cooling warping data.

[0096] Furthermore, methods for obtaining cooling warp data include:

[0097] S31: Determine the cooling period based on the welding temperature record in the solidification and pressure holding data.

[0098] In practice, the welding temperature records in the solidification and pressure holding data are read, and the welding temperatures of adjacent acquisition times are compared sequentially according to a unified acquisition time sequence. When the welding temperature of the later acquisition time is lower than that of the earlier acquisition time, the time period between the earlier and later acquisition times is determined as a cooling acquisition segment. Cooling acquisition segments with the same end acquisition time of the earlier cooling acquisition segment and the start acquisition time of the later cooling acquisition segment are merged to obtain cooling time periods. The start time, end time, and acquisition time sequence within each cooling time period are recorded to form a cooling time period table.

[0099] For each cooling period, the welding temperature at the start time of the cooling period is subtracted from the welding temperature at the end time of the cooling period to obtain the welding temperature change for that cooling period. The welding temperature change is then recorded in association with the corresponding cooling period.

[0100] The cooling period table is used to limit the range of changes in the edge-emitting laser bar warping records; edge-emitting laser bar warping records whose acquisition time does not fall within any cooling period recorded in the cooling period table are not included in the generation of cooling warping data.

[0101] S32: Determine the reference warp direction based on the edge-emitting laser BAR strip warp record in the solidification and pressure holding data.

[0102] In practice, the warping record of the edge-emitting laser bar in the solidification and pressure holding data is read, and the warping direction of the edge-emitting laser bar corresponding to the solder solidification time is extracted according to the unified acquisition time sequence; the warping direction of the edge-emitting laser bar corresponding to the solder solidification time is determined as the reference warping direction.

[0103] The reference warp direction is used to standardize the comparison direction of the warp amount of the side-emitting laser BAR strip during the cooling period, avoiding the judgment of the warp change state based solely on the numerical change of the warp amount of the side-emitting laser BAR strip.

[0104] S33: Normalize the direction of the warping records of the edge-emitting laser BAR strips during the cooling period.

[0105] In practice, the warping record of the edge-emitting laser bar corresponding to each cooling period in the cooling period table is read. The edge-emitting laser bar warping record includes the acquisition time, the warping amount of the edge-emitting laser bar, and the warping direction of the edge-emitting laser bar. The warping direction of the edge-emitting laser bar is recorded according to the two opposite direction indicators output by the warping measurement device. The two opposite direction indicators are used to represent the two opposite warping directions of the edge-emitting laser bar along its length.

[0106] For each cooling period, record the warping of the edge-emitting laser bar strip and compare the warping direction of the edge-emitting laser bar strip with the reference warping direction. When the warping direction of the edge-emitting laser bar strip is consistent with the reference warping direction, the warping amount of the edge-emitting laser bar strip is taken as the directional normalized warping amount. When the warping direction of the edge-emitting laser bar strip is opposite to the reference warping direction, the opposite number of the warping amount of the edge-emitting laser bar strip is taken as the directional normalized warping amount.

[0107] The directional normalized warpage is used to compare the warpage changes of the edge-emitted laser bar stripes between adjacent acquisition times under the same directional aperture.

[0108] S34: Form a warping direction sequence based on the direction-normalized warping amount.

[0109] Please see Figure 3 In practice, during each cooling period, the normalized warp value corresponding to adjacent collection times is compared according to a unified collection time sequence, and the absolute value of the difference between the normalized warp value corresponding to the next collection time and the normalized warp value corresponding to the previous collection time is calculated to obtain the change range.

[0110] The measurement resolution of the warp measurement device is determined by setting the effective warp change threshold and emitting laser BAR strips. When the change amplitude is less than the effective warp change threshold, the warp change direction of the adjacent acquisition segment is recorded as no effective change.

[0111] When the change amplitude is greater than or equal to the effective warp change threshold, and the directional normalized warp amount corresponding to the next acquisition time is greater than the directional normalized warp amount corresponding to the previous acquisition time, the warp change direction of the adjacent acquisition segment is recorded as increasing along the reference warp direction.

[0112] When the change amplitude is greater than or equal to the effective warp change threshold, and the directional normalized warp amount corresponding to the next acquisition time is less than the directional normalized warp amount corresponding to the previous acquisition time, the warp change direction of the adjacent acquisition segment is recorded as decreasing along the reference warp direction.

[0113] The warping direction of all adjacent acquisition segments within each cooling period is arranged in chronological order of acquisition time to form a warping direction sequence corresponding to each cooling period.

[0114] S35: Identify the warping change state of the edge-emitting laser BAR strip during the cooling period based on the warping direction sequence, and obtain cooling warping data.

[0115] In practice, for each cooling period corresponding to the warping direction sequence, the number of records that increased along the reference warping direction, the number of records that decreased along the reference warping direction, and the number of records with no effective change are counted respectively. The number of records that increased along the reference warping direction and the number of records that decreased along the reference warping direction in each cooling period are added together to obtain the number of effective change records in each cooling period.

[0116] The direction dominance threshold is used to determine whether the proportion of records increased along the reference warp direction to the total number of valid change records, or the proportion of records decreased along the reference warp direction to the total number of valid change records, reaches a state where a single warp change direction dominates. Since the sum of the proportion of records increased along the reference warp direction to the total number of valid change records and the proportion of records decreased along the reference warp direction to the total number of valid change records is equal to one, the direction dominance threshold is set to a proportion greater than one-half to avoid two opposite warp change directions being judged as direction dominant at the same time.

[0117] The directional dominance threshold is determined by historical qualified packaging records. Historical qualified packaging records are those where the post-solder warpage detection results are within the allowable range of post-solder warpage as recorded in the packaging process document. In specific implementation, historical qualified packaging records with the same specifications as the current side-emitting laser bar strip and using the same heat sink material and solder material are read. According to the cooling period consistent with the current packaging task, the reference warpage direction is extracted and the warpage direction sequence is generated. For each historical qualified packaging record with a cooling period where the number of effective change records is greater than zero, the proportion of the number of records increased along the reference warpage direction to the number of effective change records and the proportion of the number of records decreased along the reference warpage direction to the number of effective change records are calculated respectively. The maximum value of the two proportions is determined as the directional dominance threshold. From all directional dominance ratios, the proportion values ​​greater than one-half are selected, and the smallest proportion after selection is determined as the directional dominance threshold. When the selected ratio value is empty, the directional dominance ratio threshold pre-recorded in the packaging process document for the same specification edge-emitting laser BAR bar is used as the directional dominance ratio threshold; the directional dominance ratio threshold in the packaging process document is determined by the same statistical caliber from the qualified packaging records of the same specification trial production.

[0118] When the number of valid change records during a certain cooling period is greater than zero, and the proportion of the number of records increasing along the reference warping direction to the number of valid change records is greater than or equal to the directional dominance threshold, the warping change state of the edge-emitting laser BAR strip during the corresponding cooling period is recorded as warping increase.

[0119] When the number of valid change records during a certain cooling period is greater than zero, and the proportion of the number of records decreasing along the reference warping direction to the number of valid change records is greater than or equal to the directional dominance threshold, the warping change state of the edge-emitting laser BAR strip during the corresponding cooling period is recorded as warping reduction.

[0120] When the number of valid change records during a certain cooling period is greater than zero, and the proportion of records increasing along the reference warping direction to the number of valid change records is less than the directional dominance threshold, and the proportion of records decreasing along the reference warping direction to the number of valid change records is also less than the directional dominance threshold, the warping change state of the edge-emitting laser BAR strip during the corresponding cooling period is recorded as warping unstable.

[0121] When the number of valid change records for a certain cooling period is zero, the warping change state of the edge-emitting laser BAR strip during the corresponding cooling period is recorded as having no valid warping change.

[0122] The cooling warp data includes a cooling period table, a reference warp direction, the welding temperature change corresponding to each cooling period, the warp direction sequence corresponding to each cooling period, and the warp change state of the edge-emitting laser BAR strip corresponding to each cooling period; the cooling warp data is used to generate shrinkage transfer data in the subsequent process.

[0123] S4: Based on the heat sink material data and solder layer data in the packaging data, perform shrinkage transfer determination on the cooling warp data to obtain shrinkage transfer data.

[0124] Furthermore, methods for obtaining shrinkage transfer data include:

[0125] S41: Calculate the degree of heat sink shrinkage during each cooling period based on the heat sink material data and the welding temperature change corresponding to each cooling period.

[0126] In practice, the heat sink material data in the packaging data is read, and the thermal expansion coefficient of the heat sink material is extracted from the heat sink material data; the welding temperature change corresponding to each cooling period in the cooling warp data is read; and the degree of heat sink cooling shrinkage in each cooling period is calculated based on the thermal expansion coefficient of the heat sink material and the welding temperature change corresponding to each cooling period.

[0127] The degree of heat sink shrinkage during cooling is calculated using the following formula:

[0128] ;

[0129] in, This indicates the degree of heat sink contraction during the j-th cooling period. This represents the coefficient of thermal expansion of the heat sink material. This represents the change in welding temperature during the j-th cooling period.

[0130] The degree of heat sink shrinkage during cooling is used to characterize the relative shrinkage response of the heat sink material under the influence of temperature drop during the corresponding cooling period.

[0131] S42: Calculate the solder layer transfer coefficient based on the solder layer data.

[0132] In practice, the solder layer data in the package data is read, which includes the solder layer thickness measurement value; all solder layer thickness measurement values ​​are summed and divided by the number of solder layer thickness measurement values ​​to obtain the average solder layer thickness; the solder layer thickness dispersion is calculated based on the dispersion between each solder layer thickness measurement value and the average solder layer thickness.

[0133] Solder layer thickness dispersion is calculated using the following formula:

[0134] ;

[0135] in, This indicates the variation in solder layer thickness. This indicates the number of solder layer thickness measurements. This represents the measured thickness of the i-th solder layer. This indicates the average thickness of the solder layer.

[0136] Read the target solder layer thickness recorded in the packaging process document, and calculate the average solder layer thickness deviation rate based on the absolute value of the difference between the average solder layer thickness and the target solder layer thickness.

[0137] The average thickness deviation of the solder layer is calculated using the following formula:

[0138] ;

[0139] in, This indicates the deviation rate of the average thickness of the solder layer. Indicates the target solder layer thickness.

[0140] The solder layer transfer coefficient is calculated based on the average thickness deviation rate and the solder layer thickness dispersion.

[0141] The solder transfer factor is calculated using the following formula:

[0142] ;

[0143] in, Indicates the solder layer transfer coefficient. This indicates that the average thickness deviates from the weighting coefficient. This represents the thickness discrete weighting coefficient.

[0144] The average thickness deviation weighting coefficient and thickness dispersion weighting coefficient are determined by historical packaging records. In practice, historical packaging records with the same specifications as the current edge-emitting laser bar strip, using the same heat sink material and solder material, are read. The average thickness deviation rate of the solder layer, the solder layer thickness dispersion, and the warpage value from the post-soldering warpage detection results are extracted from these historical packaging records. The Pearson correlation coefficient calculation method is used to calculate the first correlation coefficient between the average thickness deviation rate of the solder layer and the warpage value, and the second correlation coefficient between the solder layer thickness dispersion and the warpage value. When the number of historical packaging records is greater than or equal to two, and the first and second correlation coefficients are compatible... When calculating, if the sum of the absolute values ​​of the first correlation coefficient and the second correlation coefficient is greater than zero, the proportion of the absolute value of the first correlation coefficient to the sum of the absolute values ​​of the first and second correlation coefficients is determined as the average thickness deviation weighting coefficient, and the proportion of the absolute value of the second correlation coefficient to the sum of the absolute values ​​of the first and second correlation coefficients is determined as the thickness dispersion weighting coefficient. When the number of historical packaging records is less than two, or either the first or second correlation coefficient cannot be calculated, or the sum of the absolute values ​​of the first and second correlation coefficients is equal to zero, both the average thickness deviation weighting coefficient and the thickness dispersion weighting coefficient are determined to be one-half.

[0145] Both the average thickness deviation weighting coefficient and the thickness dispersion weighting coefficient are dimensionless coefficients.

[0146] The solder layer transfer coefficient is used to characterize the ability of the heat sink material's cooling shrinkage effect to be transferred to the edge-emitting laser bar through the solder layer. An increase in the value of the solder layer transfer coefficient indicates that the weakening effect of the shrinkage effect caused by the average thickness deviation rate and the thickness dispersion of the solder layer is reduced.

[0147] S43: Calculate the warp transmission direction coefficient for each cooling period based on the warp direction sequence corresponding to each cooling period.

[0148] In practice, the warping direction sequence corresponding to each cooling period in the cooling warping data is read; for each cooling period, the number of records that increase along the reference warping direction and the number of records that decrease along the reference warping direction are counted, and the warping transmission direction coefficient for the corresponding cooling period is calculated.

[0149] When the sum of the number of records increasing along the reference warp direction and the number of records decreasing along the reference warp direction during the j-th cooling period is greater than zero, the warp transmission direction coefficient for the j-th cooling period is calculated according to the following formula:

[0150] ;

[0151] in, This represents the warp transmission direction coefficient during the j-th cooling period. This represents the number of records that increase along the reference warp direction during the j-th cooling period. This represents the number of records that decreased along the reference warp direction during the j-th cooling period.

[0152] When the sum of the number of records increased along the reference warp direction and the number of records decreased along the reference warp direction during the j-th cooling period is equal to zero, the warp transmission direction coefficient of the j-th cooling period is recorded as zero.

[0153] The warp propagation direction coefficient reflects the directional bias of the warp change in the edge-emitting laser bar during the corresponding cooling period. When the warp propagation direction coefficient is greater than zero, it indicates that the number of records increasing along the reference warp direction is greater than the number of records decreasing along the reference warp direction. When the warp propagation direction coefficient is less than zero, it indicates that the number of records decreasing along the reference warp direction is greater than the number of records increasing along the reference warp direction. When the warp propagation direction coefficient is equal to zero, it indicates that the number of records increasing along the reference warp direction is the same as the number of records decreasing along the reference warp direction, or the sum of the number of records increasing and decreasing along the reference warp direction is equal to zero. The absolute value of the warp propagation direction coefficient characterizes the degree of bias in the warp change direction during the corresponding cooling period.

[0154] S44: Calculate the shrinkage transfer judgment amount based on the degree of heat sink cooling shrinkage, solder layer transfer coefficient, and warpage transfer direction coefficient.

[0155] In practice, for each cooling period, the degree of heat sink shrinkage, solder layer transfer coefficient, and absolute value of warpage transfer direction coefficient for the corresponding cooling period are combined to calculate the shrinkage transfer judgment quantity for the corresponding cooling period.

[0156] The contraction transfer determination value is calculated according to the following formula:

[0157] ;

[0158] in, This represents the contraction propagation determination quantity during the j-th cooling period. This indicates the degree of heat sink contraction during the j-th cooling period. Indicates the solder layer transfer coefficient. This represents the absolute value of the warp transmission direction coefficient during the j-th cooling period.

[0159] The shrinkage transfer determination value is jointly determined by the degree of heat sink cooling shrinkage during the corresponding cooling period, the solder layer transfer coefficient, and the absolute value of the warp transfer direction coefficient. An increase in the value of the shrinkage transfer determination value indicates that the cooling shrinkage response formed by the heat sink material during the corresponding cooling period is transferred through the solder layer and acts on the warp change of the edge-emitting laser BAR strip, which is a greater comprehensive effect.

[0160] S45: Generate shrinkage transfer data based on the warping change state of the edge-emitting laser BAR strip and the shrinkage transfer determination quantity during each cooling period.

[0161] In practice, the warping change state of the edge-emitting laser BAR strips corresponding to each cooling period in the cooling warping data is read; the shrinkage transfer judgment result is determined according to the warping change state of the edge-emitting laser BAR strips corresponding to each cooling period, and the shrinkage transfer judgment quantity of each cooling period is used to characterize the degree of shrinkage transfer effect, and shrinkage transfer data is generated.

[0162] When the warping change state of the edge-emitting laser BAR strip during a certain cooling period is increased warping, the shrinkage transmission judgment result of the corresponding cooling period is recorded as transmission along the reference warping direction, and the shrinkage transmission judgment amount of the corresponding cooling period is recorded.

[0163] When the warping change state of the edge-emitting laser BAR strip during a certain cooling period is a decrease in warping, the shrinkage transmission judgment result of the corresponding cooling period is recorded as a transmission away from the reference warping direction, and the shrinkage transmission judgment amount of the corresponding cooling period is also recorded.

[0164] When the warping change state of the edge-emitting laser BAR strip during a certain cooling period is unstable, the shrinkage transmission judgment result of the corresponding cooling period is recorded as unstable transmission direction, and the shrinkage transmission judgment quantity of the corresponding cooling period is recorded.

[0165] When the warping change state of the edge-emitting laser BAR strip during a certain cooling period is no effective warping change, the shrinkage transfer judgment result of the corresponding cooling period is recorded as no effective shrinkage transfer, and the shrinkage transfer judgment quantity of the corresponding cooling period is recorded as zero.

[0166] The shrinkage transfer data includes the start and end times of each cooling period, the degree of heat sink shrinkage during each cooling period, the solder layer transfer coefficient, the warp transfer direction coefficient during each cooling period, the shrinkage transfer judgment quantity during each cooling period, and the shrinkage transfer judgment result during each cooling period; the shrinkage transfer data is used to generate subsequent pressure holding effect data.

[0167] S5: Based on the solidification and pressure holding data and shrinkage transfer data, the effect of pressure holding on the warping of the laser-emitting BAR stripe on the opposite side after solder solidification is determined, and the pressure holding effect data is obtained.

[0168] Furthermore, methods for obtaining pressure-holding data include:

[0169] S51: Determine the holding time period based on the solidification and holding pressure data, and form a holding time period table.

[0170] In practice, the solder solidification time and welding pressure release time in the solidification and pressure holding data are read; the time interval with the solder solidification time as the start time and the welding pressure release time as the end time is determined as the pressure holding period, and the start and end times of the pressure holding period are recorded to form a pressure holding period table.

[0171] The pressure holding period table is used to define the time range during which welding pressure continues to act after the solder solidifies, and is used to determine the extraction range of welding pressure records in combination with each cooling period.

[0172] S52: Based on the pressure holding period table and the start and end times of each cooling period, construct a set of adjacent acquisition segments.

[0173] In practice, the pressure holding period table is read, and the start and end times of each cooling period in the shrinkage transfer data are read. Within the pressure holding period range recorded in the pressure holding period table, for each cooling period, the welding pressure record with a collection time greater than or equal to the start time of the corresponding cooling period and less than or equal to the end time of the corresponding cooling period is extracted from the welding pressure record in the solidification pressure holding data.

[0174] Based on the unified acquisition time sequence in the solidification and pressure holding data, the time interval between the acquisition times corresponding to two adjacent welding pressure records is determined as the adjacent acquisition segment. All adjacent acquisition segments within each cooling period are then aggregated to obtain the set of adjacent acquisition segments for that cooling period. When the number of welding pressure records within a certain cooling period is less than two, the corresponding cooling period is marked as a cooling period with insufficient pressure records. Cooling periods with insufficient pressure records do not have an adjacent acquisition segment set constructed and are not included in the calculation of pressure holding degree and pressure holding effect determination quantities.

[0175] The set of adjacent acquisition segments is used to reflect the maintenance of welding pressure during the corresponding cooling period between continuous acquisition times, and is used for subsequent calculation of the pressure maintenance degree.

[0176] S53: Calculate the pressure retention level during each cooling period based on the set of adjacent acquisition segments.

[0177] In practice, the welding pressure corresponding to the solder solidification time in the solidification and holding pressure data is read, and the welding pressure corresponding to the solder solidification time is determined as the reference holding pressure.

[0178] For each set of adjacent acquisition segments corresponding to a cooling period, the welding pressure corresponding to the start acquisition time and the welding pressure corresponding to the end acquisition time of each adjacent acquisition segment are read respectively; the minimum value between the welding pressure corresponding to the start acquisition time and the welding pressure corresponding to the end acquisition time of the adjacent acquisition segment is determined as the interval holding pressure of the corresponding adjacent acquisition segment.

[0179] The pressure holding degree during the corresponding cooling period is calculated based on the interval holding pressure and the reference holding pressure of each adjacent sampling segment within the corresponding cooling period.

[0180] The pressure retention level is calculated using the following formula:

[0181] ;

[0182] in, This indicates the degree of pressure maintenance during the j-th cooling period. This represents the number of adjacent data collection segments corresponding to the j-th cooling period. This indicates the j-th cooling period. The pressure is maintained between adjacent acquisition segments. , This indicates the reference holding pressure.

[0183] The pressure holding degree is used to characterize the average holding ratio of the interval holding pressure of each adjacent acquisition segment to the reference holding pressure during the corresponding cooling period; a pressure holding degree greater than or equal to one indicates that the average holding ratio of the interval holding pressure to the reference holding pressure during the corresponding cooling period is greater than or equal to one; a pressure holding degree less than one indicates that the average holding ratio of the interval holding pressure to the reference holding pressure during the corresponding cooling period is less than one.

[0184] S54: Calculate the pressure holding effect judgment quantity for each cooling period based on the pressure holding degree and the contraction transmission judgment quantity.

[0185] In practice, the shrinkage transfer judgment quantity corresponding to each cooling period in the shrinkage transfer data is read, and the pressure holding degree of each cooling period is combined with the shrinkage transfer judgment quantity of the corresponding cooling period to calculate the pressure holding effect judgment quantity of each cooling period.

[0186] The pressure holding effect determination value is calculated according to the following formula:

[0187] ;

[0188] in, This represents the pressure holding effect determination quantity during the j-th cooling period. This indicates the degree of pressure maintenance during the j-th cooling period. This represents the contraction transmission determination quantity during the j-th cooling period.

[0189] The pressure holding effect determination quantity is jointly determined by the pressure holding degree and the shrinkage transmission determination quantity during the corresponding cooling period; an increase in the value of the pressure holding effect determination quantity indicates that the combined influence of the welding pressure holding ratio and the shrinkage transmission effect degree during the corresponding cooling period is increased.

[0190] S55: Generate pressure holding effect data based on the pressure holding effect determination quantity and the shrinkage transmission determination result.

[0191] In practice, the shrinkage transfer judgment results corresponding to each cooling period in the shrinkage transfer data are read, and the pressure holding benchmark threshold is determined based on the historical qualified packaging records. The historical qualified packaging records are packaging records in which the post-soldering warpage detection results are within the allowable range of post-soldering warpage recorded in the packaging process document.

[0192] The pressure holding effect benchmark threshold is used to compare with the pressure holding effect judgment quantity to distinguish whether the pressure holding effect after solder solidification during the corresponding cooling period reaches the pressure holding effect benchmark reflected in the historical qualified packaging records. When determining the pressure holding effect benchmark threshold, historical qualified packaging records with the same side-emitting laser BAR bar specifications as the current one, and using the same heat sink material and the same solder material are read; according to the shrinkage transfer data generation, pressure holding period determination, adjacent acquisition segment set construction, pressure holding degree calculation, and pressure holding effect judgment quantity calculation caliber consistent with the current packaging task, the shrinkage transfer judgment result and pressure holding effect judgment quantity corresponding to each cooling period in the historical qualified packaging records are obtained; from the cooling periods in the historical qualified packaging records where the shrinkage transfer judgment result is transfer along the benchmark warp direction, transfer away from the benchmark warp direction, or transfer direction is unstable, and the corresponding pressure holding effect judgment quantity is greater than zero, the corresponding pressure holding effect judgment quantity is extracted, and the minimum value among the extracted pressure holding effect judgment quantities is determined as the pressure holding effect benchmark threshold. When the extracted pressure holding effect judgment quantity is empty, the pressure holding effect reference threshold pre-recorded for the same specification edge-emitting laser BAR bar in the packaging process document is read; the pressure holding effect reference threshold in the packaging process document is determined by the same calculation caliber from the qualified packaging records of the same specification trial production.

[0193] The pressure holding effect reference threshold is used to represent the lower bound of the pressure holding effect judgment quantity corresponding to the cooling period in the historical qualified packaging record where the shrinkage transmission judgment result is transmission along the reference warp direction, transmission away from the reference warp direction, or transmission direction is unstable, and the pressure holding effect judgment quantity is greater than zero.

[0194] When the result of the contraction transfer determination during a certain cooling period is no effective contraction transfer, the result of the pressure holding effect determination during the corresponding cooling period is recorded as no effective pressure holding effect.

[0195] When the contraction transmission determination result of a certain cooling period is transmission along the reference warping direction, transmission away from the reference warping direction, or transmission direction is unstable, and the pressure holding effect determination amount of the corresponding cooling period is greater than or equal to the pressure holding effect reference threshold, the pressure holding effect determination result of the corresponding cooling period is recorded as the pressure holding effect has reached the reference.

[0196] When the contraction transmission judgment result of a certain cooling period is transmission along the reference warping direction, transmission away from the reference warping direction, or transmission direction is unstable, and the pressure holding effect judgment amount of the corresponding cooling period is less than the pressure holding effect reference threshold, the pressure holding effect judgment result of the corresponding cooling period is recorded as insufficient pressure holding effect.

[0197] The pressure holding effect data includes a pressure holding period table, a set of adjacent acquisition segments corresponding to each cooling period, the pressure holding degree of each cooling period, the shrinkage transmission judgment result corresponding to each cooling period, the pressure holding effect judgment quantity of each cooling period, the pressure holding effect benchmark threshold, and the pressure holding effect judgment result of each cooling period; the pressure holding effect data is used to generate the encapsulation stress compensation result in the subsequent process.

[0198] S6: Based on the pressure holding data, the welding pressure or welding temperature curve during the edge-emitting laser BAR strip packaging process is compensated and adjusted to obtain the packaging stress compensation result.

[0199] Furthermore, methods for obtaining the packaging stress compensation results include:

[0200] S61: Based on the pressure holding effect determination results, screen the cooling period to be compensated and calculate the pressure holding effect gap ratio.

[0201] In practice, the pressure holding effect judgment results, pressure holding effect judgment quantities, pressure holding effect benchmark thresholds, and contraction transfer judgment results corresponding to each cooling period in the pressure holding effect data are read.

[0202] When the pressure holding effect of a certain cooling period is determined to be insufficient, the corresponding cooling period is designated as a cooling period to be compensated; when the pressure holding effect of a certain cooling period is determined to be at the benchmark level or without effective pressure holding, the corresponding cooling period is designated as a non-compensated cooling period.

[0203] Since the holding pressure reference threshold is determined by the cooling period in the historical qualified packaging record where the holding pressure judgment value is greater than zero, or by the holding pressure reference threshold pre-recorded in the packaging process document for the same specification edge-emitting laser BAR strip, the holding pressure reference threshold is greater than zero. For each cooling period to be compensated, the holding pressure gap ratio is calculated based on the holding pressure reference threshold and the corresponding holding pressure judgment value for the cooling period to be compensated.

[0204] The proportion of the pressure-holding gap is calculated according to the following formula:

[0205] ;

[0206] in, This represents the proportion of the pressure holding gap during the j-th cooling period that needs compensation. This indicates the reference threshold for the pressure holding effect. This represents the pressure holding effect determination quantity for the j-th cooling period to be compensated.

[0207] For the cooling period to be compensated where the pressure holding effect is deemed insufficient, the pressure holding effect gap ratio is greater than zero. The pressure holding effect gap ratio is used to characterize the degree of gap between the pressure holding effect judgment value and the pressure holding effect benchmark threshold during the cooling period to be compensated; an increase in the value of the pressure holding effect gap ratio indicates a greater degree of insufficient pressure holding effect during the corresponding cooling period to be compensated.

[0208] S62: Determine the compensation adjustment object based on the contraction transfer judgment result corresponding to the cooling period to be compensated.

[0209] In practice, the contraction transfer judgment result corresponding to each cooling period to be compensated is read, and the compensation adjustment object is determined based on the contraction transfer judgment result.

[0210] When the shrinkage transmission determination result corresponding to the cooling period to be compensated is that it is transmitted along the reference warping direction or away from the reference warping direction, the compensation adjustment object for the corresponding cooling period to be compensated is determined to be the welding pressure.

[0211] When the shrinkage transmission determination result corresponding to the cooling period to be compensated is that the transmission direction is unstable, the compensation adjustment object corresponding to the cooling period to be compensated is determined to be the welding temperature curve.

[0212] The compensation adjustment target is used to distinguish whether welding pressure compensation or welding temperature curve compensation is used for the corresponding cooling period to be compensated. When the shrinkage transmission judgment result is that it is transmitted along the reference warp direction or away from the reference warp direction, welding pressure compensation is used to enhance the pressure holding constraint effect after the weld solidification during the corresponding cooling period to be compensated. When the shrinkage transmission judgment result is that the transmission direction is unstable, welding temperature curve compensation is used to adjust the original cooling duration and the time position of each intermediate control node for the corresponding cooling period to be compensated.

[0213] S63: Adjust the welding pressure according to the proportion of the pressure holding gap to generate welding pressure compensation content.

[0214] In practice, for the cooling period to be compensated where the compensation adjustment object is the welding pressure, the original welding pressure control value associated with the corresponding cooling period is read from the packaging process document or welding equipment control parameter record; and the pressure compensation calculation value is calculated based on the pressure holding effect gap ratio of the corresponding cooling period.

[0215] The pressure compensation value is calculated according to the following formula:

[0216] ;

[0217] in, This represents the calculated pressure compensation value for the j-th cooling period to be compensated. This represents the original welding pressure control value during the j-th cooling period to be compensated. This represents the proportion of the pressure holding gap during the j-th cooling period that needs to be compensated.

[0218] Read the upper limit of allowable pressure for edge-emitting laser bar packaging as recorded in the packaging process document, and read the upper limit of allowable pressure for welding equipment as recorded in the welding equipment control parameter record; determine the minimum value between the upper limit of allowable pressure for edge-emitting laser bar packaging and the upper limit of allowable pressure for welding equipment as the upper limit of pressure compensation.

[0219] If the calculated pressure compensation value is less than or equal to the upper limit of pressure compensation, the calculated pressure compensation value is determined as the control value of welding pressure after compensation; if the calculated pressure compensation value is greater than the upper limit of pressure compensation, the upper limit of pressure compensation is determined as the control value of welding pressure after compensation, and the pressure limit mark is recorded.

[0220] The welding pressure compensation content includes the cooling period to be compensated, the original welding pressure control value, the holding pressure gap ratio, the calculated pressure compensation value, the upper limit of pressure compensation, the welding pressure control value after compensation, and the pressure limit mark. When the pressure limit mark is not recorded, the increase in the compensated welding pressure control value relative to the original welding pressure control value is determined by the product of the original welding pressure control value and the holding pressure gap ratio; when the pressure limit mark is recorded, the compensated welding pressure control value is based on the upper limit of pressure compensation. The welding pressure compensation content is used to adjust the welding pressure control value used during the cooling period to be compensated when the holding pressure is insufficient and the shrinkage transmission result is either transmitted along the reference warp direction or away from the reference warp direction.

[0221] S64: Based on the proportion of the pressure holding gap, the welding temperature curve is compensated and adjusted to generate the welding temperature curve compensation content.

[0222] In practice, for the cooling period to be compensated, which is the target of the compensation adjustment, the control data of the welding temperature curve associated with the corresponding cooling period is read from the packaging process document or the control parameter record of the welding equipment. The control data of the welding temperature curve includes the start control time of the cooling period, the start control temperature of the cooling period, the original end control time of the cooling period, the end control temperature of the cooling period, the original cooling duration, and intermediate control nodes. The intermediate control nodes include the intermediate node control time and the intermediate node control temperature. The intermediate node control time is located between the start control time of the cooling period and the original end control time of the cooling period. The original cooling duration is the time difference between the original end control time of the cooling period and the start control time of the cooling period.

[0223] Based on the pressure holding gap ratio of the corresponding cooling period to be compensated, the original cooling duration is adjusted to obtain the compensated cooling duration.

[0224] The cooling time after compensation is calculated according to the following formula:

[0225] ;

[0226] in, This represents the duration of the post-compensation cooling in the j-th cooling period to be compensated. This represents the original cooling duration of the j-th cooling period to be compensated. This represents the proportion of the pressure holding gap during the j-th cooling period that needs to be compensated.

[0227] The compensated cooling duration is superimposed with the start control time of the cooling period to obtain the compensated termination control time. The start control temperature, termination control temperature, and intermediate node control temperature of each intermediate control node are kept constant. For each intermediate control node, the time difference between the intermediate node control time and the start control time of the cooling period is calculated, and this time difference is divided by the original cooling duration to obtain the time ratio corresponding to the intermediate control node. This time ratio is multiplied by the compensated cooling duration to obtain the node relative time of the corresponding intermediate control node within the compensated cooling duration. The node relative time is superimposed with the start control time of the cooling period to obtain the compensated node control time of the corresponding intermediate control node.

[0228] The starting control time and starting control temperature of the cooling period are combined to form the compensated starting control node. The control time of each compensated node is combined with the intermediate node control temperature of the corresponding intermediate control node to form the compensated intermediate control node. The ending control time and ending control temperature of the cooling period are combined to form the compensated ending control node. The welding temperature curve of the corresponding cooling period to be compensated is reconstructed according to the time sequence of the compensated starting control node, each compensated intermediate control node and the compensated ending control node to obtain the compensated welding temperature curve.

[0229] The welding temperature profile compensation includes the cooling period to be compensated, the start control time of the cooling period, the start control temperature of the cooling period, the original end control time of the cooling period, the end control temperature of the cooling period, the original cooling duration, the pressure holding effect gap ratio, the cooling duration after compensation, the end control time after compensation, the control time of each intermediate control node after compensation, and the compensated welding temperature profile. The cooling duration after compensation is greater than the original cooling duration, and the increase in cooling duration is determined by the product of the original cooling duration and the pressure holding effect gap ratio. The welding temperature profile compensation is used to extend the cooling duration of the cooling period to be compensated when the transmission direction is unstable, while keeping the start control temperature and the end control temperature of the cooling period unchanged.

[0230] S65: Generate the encapsulation stress compensation result based on the welding pressure compensation content and the welding temperature curve compensation content.

[0231] In practice, the compensation adjustment objects corresponding to each cooling period to be compensated, the pressure holding gap ratio corresponding to each cooling period to be compensated, the welding pressure compensation content, and the welding temperature curve compensation content are associated and summarized according to the cooling period to be compensated to obtain the encapsulation stress compensation result.

[0232] The encapsulation stress compensation results include the cooling period to be compensated, the cooling period not compensated, the compensation adjustment objects corresponding to each cooling period to be compensated, the pressure holding effect notch ratio corresponding to each cooling period to be compensated, the welding pressure compensation content, and the welding temperature curve compensation content. The encapsulation stress compensation results are used to correct the welding pressure control parameters or welding temperature curve control parameters in subsequent edge-emitting laser BAR strip encapsulation tasks.

[0233] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for compensating for thermal stress in the packaging of an edge-emitting laser bar strip, characterized in that, include: The packaging data of the edge-emitting laser bar is obtained. The packaging data includes heat sink material data, solder layer data, welding temperature record, welding pressure record, and edge-emitting laser bar warpage record. The packaging data is then processed to obtain packaging timing data. Solder solidification time and welding pressure release time are extracted from the packaging timing data. The packaging timing data is then truncated in intervals, with solder solidification time as the start time and welding pressure release time as the end time, to obtain solidification and holding pressure data. The cooling period is determined based on the welding temperature record in the solidification and pressure holding data, and the change state of the edge-emitting laser BAR strip warping record during the cooling period is identified to obtain the cooling warping data. Based on the heat sink material data and solder layer data in the packaging data, shrinkage transfer is determined by the cooling warp data to obtain shrinkage transfer data. Based on solidification and pressure holding data and shrinkage transfer data, the effect of pressure holding on the warping of the laser-emitting BAR stripe on the opposite side after solder solidification is determined, and pressure holding effect data is obtained. Based on the pressure holding data, the welding pressure or welding temperature curves during the edge-emitting laser BAR strip packaging process are compensated and adjusted to obtain the packaging stress compensation results.

2. The method for thermal stress packaging compensation of an edge-emitting laser bar strip according to claim 1, characterized in that, The method for obtaining cooling warp data includes: Compare the welding temperature records that are adjacent in time sequence in the solidification and holding pressure data. The time period between adjacent records where the welding temperature in the later welding temperature record is lower than the welding temperature in the earlier welding temperature record is determined as the cooling acquisition segment. Then, merge the adjacent cooling acquisition segments to obtain the cooling period. The warping direction of the edge-emitting laser BAR strip warping record during the cooling period is extracted, and the warping direction is arranged in chronological order to obtain the warping direction sequence. The warping direction sequence is identified to obtain the warping change state of the edge-emitting laser BAR strips corresponding to each cooling period. Record the cooling period, the reference warp direction, the welding temperature change corresponding to each cooling period, the warp direction sequence, and the warp change state of the edge-emitting laser BAR strip corresponding to each cooling period to obtain cooling warp data.

3. The method for thermal stress packaging compensation of an edge-emitting laser bar strip according to claim 2, characterized in that, The method for obtaining the warping direction sequence includes: From the edge-emitting laser bar warpage records in the solidification and holding pressure data, the edge-emitting laser bar warpage direction corresponding to the solder solidification time is extracted as the reference warpage direction, and the edge-emitting laser bar warpage direction and edge-emitting laser bar warpage amount during the cooling period are extracted. The warping direction of the edge-emitting laser bar is compared with the reference warping direction, and the warping amount of the edge-emitting laser bar is uniformly processed according to the reference direction based on the comparison results to obtain the direction-normalized warping amount. The absolute value of the difference in normalized warpage in adjacent time-series directions is calculated to obtain the magnitude of the change. If the change is less than the preset effective warping change threshold, the warping change direction will be determined as no effective change. If the change amplitude is greater than or equal to the preset effective warping change threshold, the warping change direction that increases or decreases along the reference warping direction is determined based on the relationship between the normalized warping amount in the latter direction and the normalized warping amount in the former direction. Arrange the warping directions in chronological order to obtain a warping direction sequence.

4. The method for thermal stress packaging compensation of an edge-emitting laser bar strip according to claim 1, characterized in that, The method for obtaining the contraction transfer data includes: Extract the welding temperature change, warping direction sequence, and warping change state of the edge-emitting laser BAR strip corresponding to each cooling period from the cooling warping data, and extract the thermal expansion coefficient of the heat sink material from the heat sink material data. Based on the thermal expansion coefficient of the heat sink material, the change in welding temperature, the solder layer data, and the warping direction sequence, the shrinkage transfer quantitative calculation is performed for each cooling period to obtain the shrinkage transfer judgment quantity corresponding to each cooling period. Based on the warping change state of the edge-emitting laser BAR strips corresponding to each cooling period, the transmission direction and effective transmission are determined for each cooling period, and the shrinkage transmission determination results for each cooling period are obtained. Record the contraction transfer determination results and contraction transfer determination quantities corresponding to each cooling period to obtain contraction transfer data.

5. The method for thermal stress packaging compensation of an edge-emitting laser bar strip according to claim 4, characterized in that, The method for obtaining the contraction transfer determination quantity corresponding to each cooling period includes: The product of the thermal expansion coefficient of the heat sink material and the welding temperature change corresponding to each cooling period is calculated to obtain the degree of heat sink cooling shrinkage during each cooling period. Thickness deviation and thickness dispersion calculations are performed on the solder layer data to obtain the average thickness deviation rate and the thickness dispersion of the solder layer; the average thickness deviation rate and the thickness dispersion of the solder layer are weighted and summed, and the reciprocal of the weighted sum is taken to obtain the solder layer transfer coefficient. The reference warp direction is extracted from the cooling warp data. The warp direction sequence corresponding to each cooling period is statistically analyzed to obtain the number of records that increase along the reference warp direction and the number of records that decrease along the reference warp direction for each cooling period. The difference between the number of records of the two types and the sum of the numbers within the same cooling period are calculated to obtain the warp transmission direction coefficient corresponding to each cooling period. The absolute values ​​of the heat sink shrinkage degree, solder layer transfer coefficient, and warpage transfer direction coefficient corresponding to each cooling period are multiplied to obtain the shrinkage transfer judgment quantity corresponding to each cooling period.

6. The method for thermal stress packaging compensation of an edge-emitting laser bar strip according to claim 4, characterized in that, The method for obtaining pressure-holding data includes: Extract the solder solidification time, welding pressure release time and welding pressure record from the solidification and pressure holding data, and determine the pressure holding period with the solder solidification time as the start time and the welding pressure release time as the end time; During the pressure holding period, the welding pressure record is truncated according to each cooling period, and the truncated welding pressure record is divided into adjacent acquisition segments to obtain the set of adjacent acquisition segments corresponding to each cooling period. Based on the set of adjacent acquisition segments corresponding to each cooling period and the contraction transmission judgment quantity corresponding to each cooling period, the pressure holding effect is quantitatively calculated for each cooling period to obtain the pressure holding effect judgment quantity corresponding to each cooling period. Based on the shrinkage transfer judgment results, the pressure holding effect judgment quantity, and the pressure holding effect benchmark threshold corresponding to each cooling period, the pressure holding effect is judged for each cooling period, and the pressure holding effect judgment results corresponding to each cooling period are obtained. The pressure holding effect judgment quantity, pressure holding effect benchmark threshold, and pressure holding effect judgment results corresponding to each cooling period are recorded to obtain the pressure holding effect data.

7. The method for thermal stress packaging compensation of an edge-emitting laser bar strip according to claim 6, characterized in that, The method for obtaining the pressure holding effect determination quantity corresponding to each cooling period includes: The welding pressure corresponding to the solidification time of the solder is extracted from the welding pressure record to obtain the reference holding pressure. Read the welding pressure at both ends of each adjacent acquisition segment in the set of adjacent acquisition segments corresponding to each cooling period, and determine the minimum value of the welding pressure at both ends as the interval holding pressure; The ratio of the pressure maintained in each interval to the benchmark pressure is calculated, and the ratios of adjacent sampling segments within the same cooling period are averaged to obtain the pressure maintenance degree for each cooling period. The pressure holding effect judgment quantity for each cooling period is obtained by multiplying the pressure holding degree for each cooling period with the contraction transmission judgment quantity for each cooling period.

8. The method for thermal stress packaging compensation of an edge-emitting laser bar strip according to claim 6, characterized in that, The method for obtaining the packaging stress compensation result includes: Extract the pressure holding effect judgment result, pressure holding effect judgment quantity and pressure holding effect benchmark threshold corresponding to each cooling period from the pressure holding effect data, and determine the cooling period with insufficient pressure holding effect as the cooling period to be compensated. Subtract the corresponding pressure holding effect judgment quantity from the pressure holding effect benchmark threshold corresponding to the cooling period to be compensated, and calculate the ratio of the difference to the pressure holding effect benchmark threshold to obtain the pressure holding effect gap ratio; Based on the shrinkage transmission judgment result corresponding to the cooling period to be compensated, the compensation adjustment object is determined, and the compensation adjustment object is the welding pressure or welding temperature curve. Based on the pressure holding gap ratio, the compensation adjustment object is adjusted to obtain the welding pressure compensation content or welding temperature curve compensation content. Record the cooling period to be compensated, the object to be compensated, the proportion of the pressure holding gap, and the welding pressure compensation content or welding temperature curve compensation content corresponding to the object to be compensated, to obtain the encapsulation stress compensation result.

9. A method for compensating for thermal stress in the packaging of an edge-emitting laser bar strip according to claim 8, characterized in that, The method for determining the compensation adjustment object includes: Extract the baseline warp direction from the cooling warp data and read the contraction transfer determination result corresponding to the cooling period to be compensated; When the shrinkage transfer determination result is that it is transferred along the reference warping direction or deviates from the reference warping direction, the welding pressure is determined as the compensation and adjustment object. When the shrinkage transfer determination result indicates that the transfer direction is unstable, the welding temperature curve is determined as the object of compensation and adjustment.

10. A method for compensating for thermal stress in the packaging of an edge-emitting laser bar strip according to claim 8, characterized in that, The method for obtaining the welding temperature curve compensation content includes: Obtain the welding temperature curve control data corresponding to the cooling period to be compensated, and extract the start control time of the cooling period, the original cooling duration, and the control time of each intermediate control node. Based on the pressure holding gap ratio, the original cooling time is extended to obtain the compensated cooling time; and the compensated cooling time is added to the starting control time of the cooling period to obtain the compensated termination control time. Calculate the time difference between the control time of each intermediate control node and the start control time of the cooling period, and calculate the ratio of the time difference to the original cooling duration to obtain the time ratio of each intermediate control node; based on the time ratio, map each intermediate control node to the compensated cooling duration to obtain the control time of each compensated node. Based on the termination control time and control time of each node after compensation, the termination control time of the cooling period and the control time of each intermediate control node in the welding temperature curve control data are updated to obtain the welding temperature curve compensation content.

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