JP2005286015A - Packaging quality factor analysis method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To analyze various failure factors by performing comparative analysis for the result of a preceding process in a packaging process and to stabilize quality by restraining quality defect. <P>SOLUTION: The method has a function 2 for narrowing down a process which is considered as a factor based on repair result which is quality final information in the packaging process, a function 3 for narrowing down a process and a failure factor by comparing to the inspection result of the preceding process based on a component name and a lead number and a function 4 for narrowing down the failure factor the process based on inspection measurement result. Since quality defect can be restrained by investigating the true factor of generated failures, quality is stabilized. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a packaging quality factor analysis method for the purpose of improving quality in a substrate mounting process.

In the conventional quality analysis method in the mounting process, inspection is performed for each of the solder printing process, component mounting process, and soldering process, and the results are fed back to the own process equipment. The determined actual failure result was not reflected, and the exact failure factor could not be specified. (For example, see Patent Document 1)
FIG. 10 shows a typical configuration of the mounting process. In FIG. 10, the head is the solder printing step 20 with respect to the direction in which the board is transported, and includes a solder printing machine 23 that prints solder on the board, and a solder printing inspection machine 24 that checks the printed state of the solder. Is done. The solder printing inspection machine 24 feeds back the inspection result to the solder printing machine 23.

  The next step after the solder printing step 20 is a component mounting step 21. This process includes a component mounting machine 25 that mounts electronic components on a printed board of solder, and a component mounting inspection machine 26 that inspects the mounting state.

  The next step after the component mounting step 21 is a soldering step 22, which is a component soldering machine 27 that solders the solder printed in the solder printing step 20 and the component mounted in the component mounting step 21. And an appearance inspection machine 28 for inspecting the soldered substrate. This inspection is the final inspection to be inspected by the inspection machine. The defective part is repaired after the defect is manually confirmed in the repair process 29.

  As shown in FIG. 10, in the conventional defect factor analysis in such a mounting process, the solder printing process 20 is analyzed in the solder printing process 20 based on the solder printing inspection result. This is fed back to the machine 24. In the component mounting process 21, the analysis in the component mounting process 21 is performed based on the inspection result of the component mounting inspection machine 26, and the result is fed back to the component mounting machine 25. In the soldering process 22, the analysis of the soldering process 22 is performed based on the inspection result of the appearance inspection machine 28, and the result is fed back to the component soldering machine 27.

Based on the fed back information, equipment maintenance and parameter change are performed so as to prevent the occurrence of defects, thereby suppressing the occurrence of defects.
JP-A-11-298200 (pages 4-5, FIG. 1)

  However, in the conventional configuration, the inspection result of the inspection machine in each process is fed back only to each process and the defect is suppressed, so in this method, the true factor for a certain defect is in other processes. If it exists, the cause of the failure cannot be grasped. In addition, along with recent downsizing and higher functionality of products, mounting boards are becoming smaller and higher density, and mounting parts are also becoming smaller and parts with solder joints at the bottom of the parts. In some cases, a defect cannot be found only by the inspection technique, and the conventional feedback for each process has a problem that the cause of the true defect cannot be clarified.

  The present invention solves the above-described conventional problems, and not only provides feedback of inspection results within the process, but also correlates inspection results between processes, and investigates the true failure factor process and failure factors of the generated defects. An object of the present invention is to provide a mounting quality factor analysis method capable of suppressing the occurrence of defects.

  In order to achieve the above object, the invention according to claim 1 of the present invention is the solder printing inspection result in the solder printing process, the component mounting inspection result in the component mounting process, and the appearance inspection result in the soldering process. Based on the information on the repair result of the board and the quality database in which the circuit design information is registered, based on the registered repair part result, the defect status of the part in each process is indicated by part name and lead unit. The cause of failure and analysis of the cause of failure and analysis of the process to be analyzed and the results of processing between the processes, analysis of the results of processing between processes, whether there is a factor in the previous process And a specific process.

  The invention according to claim 2 is characterized in that in the defect factor specifying step, the component name and each step in the lead unit are associated with each other and the defect state is analyzed.

  The invention according to claim 3 is a process of acquiring the part inspection result in each process, a process of counting the defect occurrence state of the part in each process by the part name and the lead unit, and the measurement of the part name and the lead unit Based on the measurement results determined to be defective from the results, the measurement information is displayed in a time series or a histogram, and a defect factor identifying process for identifying a defect factor process and a defect factor from a display tendency is provided.

  According to a fourth aspect of the present invention, in the factor analysis method according to any one of the first to third aspects, a set value is provided for the transition of the measured value over time, and an alarm is given if the measured value exceeds a set threshold value. It is characterized by putting out.

  The invention according to claim 5 is the factor analysis method according to any one of claims 1 to 3, wherein a threshold is provided for the degree of variation when the measured value is statistically processed, and the measured value exceeds the set threshold It is characterized by issuing an alarm.

  With this configuration, the true cause of the defect that occurs in the mounting process can be investigated, and the mounting defect can be greatly reduced as compared to the conventional case.

  As described above, according to the mounting quality factor analysis method of the present invention, it is possible to discriminate according to the cause of the quality failure that occurs, and to determine the cause of the failure based on the part name and the lead number of the component for each distinguished factor. It is possible to provide a quality control method capable of narrowing down the possible processes and determining the cause of the defect, thereby significantly reducing the quality defect as compared with the prior art.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a flowchart of a mounting quality factor analysis method according to Embodiment 1 of the present invention. The mounting quality factor analysis method according to the embodiment of the present invention includes a step of obtaining a repair result from a quality database, a step of statistically processing a defective state of a component in each step from a defective component name by a graph display, etc. Analyzing the results of the above process, comparing the process of analyzing whether there is a factor in the previous process and the inspection result and graph of the previous process based on the part name and lead number, It is characterized by comprising a step of narrowing down.

  This will be described in detail below.

  In FIG. 1, the quality database 1 includes a solder printing inspection result in the solder printing step 20, a component mounting inspection result in the component mounting step 21, an inspection result in the soldering step 22, a repair result, circuit design information, Implementation conditions are stored. These are shown in a block diagram in FIG.

  In FIG. 2, the solder printing inspection result in the solder printing process 20 stores the solder inspection result on the land for each board, and the stored information indicates that the solder to which which lead on which board on which board is bonded is defective. Whether or not it is defective is stored measurement data at the time of determination.

  The component mounting inspection result of the component mounting process 21 stores the component inspection result for each board, and in that information, which part of which board is defective, which lead of which part is defective, Measurement data at the time of determination is stored.

  As the appearance inspection result of the soldering process 22, the inspection result for each board is stored, and in that information, which part of which board and which lead are defective and measurement data at the time of determination are stored. .

  As for the repair result, parts and leads that have become defective in the soldering process 22 are manually inspected, and the determination result at that time is the final determination, and this result is stored in units of boards.

  The circuit design information 30 stores design information such as component positions and component shapes.

  The mounting condition 31 stores data such as printing speed and solder viscosity in the solder printing process 20, and stores data such as a cassette number and component position in the component mounting process 21, and the soldering process 22. Stores data such as the temperature of the heater at the time of soldering and the board conveyance speed.

  Based on the above data, a process for producing a substrate and a process for reducing defects will be described. First, the solder printing machine 23 prints cream solder on the land of the substrate, and the printed state is inspected by the solder printing inspection machine 24. At this time, which land of which substrate is at the warning level and the measured value at that time are stored in the quality database 1. The inspection items here include solder height, solder volume, and positional deviation.

  Next, in the component mounting process 21, components are mounted by the component mounting machine 25 on the land printed with solder in the solder printing process 20, and the mounting state is inspected by the component mounting inspection machine 26. At this time, which parts and leads of which board are at the warning level and the measured values at that time are stored in the quality database 1. The inspection items here include items such as component height, component position deviation, and no component.

  Next, in the soldering step 22, the cream solder is reflowed, the components are soldered to the substrate, and the state of the mounting substrate is inspected by the appearance inspection machine 28. At this time, which parts and leads of which board are defective and the measured values at that time are stored in the quality database. The inspection items here include items such as component height, component position deviation, and no component.

  Next, based on the appearance inspection result, a defect is manually confirmed, and the result of determining whether or not it is actually defective is stored in the quality database 1.

  FIG. 3 shows a flow for specifically extracting a defect factor process using these data. First, based on the repair result from the quality database 1, the part inspection result in each process is acquired, and the inspection status is compared as shown in FIG. FIG. 4 is a summary of the failure occurrence status of each process in units of parts, and a process that can be considered as a failure occurrence factor can be extracted according to the failure occurrence status in each process. For example, if there are many defects in the part named “C123” in the repair result, it is confirmed whether or not there is a defect in “C123” by visual inspection. This means that the soldering process, which is the previous process, is considered to include a defect factor. In addition, if a component failure occurs in “C123” in the component mounting inspection as the previous process, it is considered that the mounting process includes a failure factor because it is defective from the previous process.

  As an example, when it is determined that the component “C123” is misaligned in the repair result, as shown in FIG. 4 in order to determine whether the cause is in the soldering process or the component mounting process. Refer to the determination result in the component mounting process. If the corresponding part is defective in the part mounting process, it means that there is a factor before the part mounting process. If it is a non-defective product in the part mounting process, there is a factor in the soldering process. Conceivable.

  When it is considered that there is a factor before the component mounting process, it is confirmed in the same manner as the procedure shown in FIG. 4 how the printed state of the lead of the corresponding component in the solder printing process is. If the printed state of the lead of the relevant part is defective, it can be considered that there is a factor in the solder printing process.

  Next, as another method for identifying the cause of failure, a method for identifying the degree of variation in the measurement results of each process will be described with reference to FIG. The process up to the process of counting the defect occurrence status of parts in each process by part name and lead unit is the same as the above embodiment. In this method, as shown in FIG. 5, a defective part is identified based on a measurement result which is a determination criterion at the time of defect determination from the defect total 50 for each part and lead, and the measurement value information of the part is time-sequentially. Display 51 and specify the failure factor process and the failure factor from the display tendency of the measured value. Further, the measurement value information is displayed as a histogram 52, and the defect factor process and the factor are specified from the relationship between the defect phenomenon and the variation of the measurement value. The operation flow at this time is as follows. Measurement value information is acquired from the inspection result of each process from the quality database 1, and the number of defects for each part name and lead number is totaled and displayed in a graph. The graph display displays a time series display of measured value information and a histogram, and the failure process and the failure factor can be analyzed by the tendency and variation. For example, in the case of a solder printing process, if the variation can be suppressed when the solder viscosity is changed, the factor is the result of the solder viscosity.

  Further, as shown in FIG. 6, the component position and component shape information are acquired from the circuit design information 30, and the factors are analyzed based on the position of the defective component on the substrate 60 and the frequency of occurrence of the defect. By displaying the parts 61 on the board 60 and the parts 62 with a high frequency of occurrence in different colors, it is possible to identify the parts that are intensively generated. Is considered to be accurate. The operation flow at this time is shown in FIG. Inspection results and circuit design information are acquired from the quality database 1, and based on this information, a component part arrangement image diagram and the degree of occurrence of defective parts are displayed. The failure distribution and the cause of failure can be analyzed based on the displayed distribution tendency of the failure occurrence.

  Further, as shown in FIG. 8, the measurement value information of the inspection machine that performs inspection in each process is set as a time series display 80, and the threshold value for setting the upper limit value and the lower limit value of the warning value is included in the display separately from the inspection machine. Thus, when the measured value exceeds the threshold value, an alarm can be output before the NG determination is made by the inspection machine, so that it is possible to identify the cause of the failure in advance and take measures to prevent the failure. Further, in the histogram 81, an upper limit and a lower limit are set in advance in the width of variation, and an alarm is output when the variation occurs when the upper limit or the lower limit is exceeded. Identification becomes possible. The operation at this time is shown in FIG. By acquiring the measurement result from the quality database 1, providing a threshold value for the time series display and the histogram, and outputting an alarm when this value is exceeded, it becomes possible to identify the failure factor process and the failure factor in advance.

  The mounting quality factor analysis method of the present invention has a function of narrowing down various causes of defects in the mounting process for each process and specifying the factor, and can be applied to the use of a quality control method such as a device manufacturing process.

Flow chart of mounting quality factor analysis in Embodiment 1 of the present invention Quality database block diagram Process diagram for implementing the present invention Diagram showing correlation of inspection results for each process Diagram showing statistical analysis Distribution diagram of defective parts on the board Process diagram for checking substrate defect occurrence status Process diagram for statistical analysis Diagram showing alarm occurrence Block diagram of conventional mounting quality factor analysis method

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Quality database 2 Process description 3 Process description 4 Process description 5 Process description 6 Process description 7 Process description 8 Process description 9 Process description 10 Process description 20 Printing process 21 Component mounting process 22 Soldering process 23 Solder printer 24 Solder printing inspection machine 25 Component Mounting Machine 26 Component Mounting Inspection Machine 27 Soldering Machine 28 Appearance Inspection Machine 29 Repair Process 30 Circuit Design Information 31 Mounting Condition 50 Defect Generation Status 51 Time Series Display 52 Histogram 60 Substrate 61 Component 62 Component with High Defect Frequency 80 O'clock Alarm generation by series display 81 Alarm generation by histogram

Claims (5)

   A mounting quality factor analysis method for analyzing a factor of a defective phenomenon in a board mounting process, a solder printing inspection result in a solder printing process, a component mounting inspection result in a component mounting process, and a soldering process in the board mounting process The external inspection result and the repair result of the board repair based on the inspection result of the visual inspection for each part name and lead number, and the design information such as the part position and part shape as circuit design information, respectively The process of registering in the quality database, the process of obtaining the part inspection result in each process based on the repair result from the quality database, and the defect occurrence status of the part in each process in part name and lead unit Aggregate and statistically process the aggregation results, analyze the processing results between processes, and analyze whether there is a factor in the previous process in order, and identify the cause of failure and the cause of failure. Mounting quality factor analysis method consisting of defective factor specifying step of.   The mounting quality factor analysis method according to claim 1, wherein the defect factor specifying step associates each step in part name and lead unit and sequentially analyzes the defect state in each step.   A mounting quality factor analysis method for analyzing a factor of a defective phenomenon in a board mounting process, a solder printing inspection result in a solder printing process, a component mounting inspection result in a component mounting process, and a soldering process in the board mounting process The external inspection result and the repair result of the board repair based on the inspection result of the visual inspection for each part name and lead number, and the design information such as the part position and part shape as circuit design information, respectively A step of registering in a quality database, a step of obtaining a part inspection result in each step from the quality database, a step of totalizing a defect occurrence state of a component in each step in a part name and lead unit, a part name and Based on the measurement result determined to be defective from the measurement result of the lead unit, the measurement information is displayed in time series or histogram, and the cause of failure is determined from the display tendency. Mounting quality factor analysis method consisting of defective factor specifying step of specifying a defective factor.   The mounting according to any one of claims 1 to 3, wherein measurement value information of an inspection machine that performs inspection in each process is displayed in time series, and an alarm is issued when the measurement value exceeds a preset threshold value. Quality factor analysis method. The measurement value information of an inspection machine that performs inspection in each process is displayed in a histogram, a threshold is provided for the degree of variation, and an alarm is issued when the measurement value exceeds a preset threshold value. The mounting quality factor analysis method described in any one of the above.

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