JPS61140105A - Marking of defective product for laser trimming process - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for marking defective products in a laser trimming process for electronic components such as resistor networks and chip resistors.

[Conventional technology]

For example, a thick film resistor network is shown in Figure 3.
A large number of blocks 1' are arranged on a ceramic substrate 1 in the form of squares in the X and Y directions, and a resistive paste is printed and fired between the conductor parts 2, 2, . After forming thick film resistance elements 3, 3, etc., and processing them so that the resistance value of each resistance element 3 becomes a predetermined value, as shown in FIG. divide,
Terminals 4 are fixed to each conductor portion 2.2 in each block 1', and the remaining portions of each terminal 4 are coated with synthetic resin 5 for finishing.

One way to adjust the resistance value of each resistive element 3 to a predetermined value is to use a measuring device to measure the resistance value of each resistive element 3 for each block 1' formed on the substrate 1. The laser beam is irradiated onto the resistance element 3 whose value is slightly smaller than the predetermined value while making the measurement by contacting it with the probe in the kerf 6.
The resistance value is increased to a predetermined value by so-called laser trimming, which involves forming a resistive film and removing a part of the resistive film.

In this case, if the resistance value of the resistor element 3 before laser trimming is outside the predetermined range, the predetermined resistance value cannot be obtained even if it is trimmed, so the block 1' containing this resistor element 3 is a defective product. It turns out that.

In addition, even if the resistance value becomes too large than a predetermined value due to a mistake in laser trimming, the block 1' that includes the part
are treated as defective products.

In this way, blocks containing defective parts do not need to be processed further, so in order to easily distinguish between them, conventionally, each time the measurement is carried out, the measuring operator manually inks the defective blocks. In the past, defective products were removed by marking the product with a symbol such as a mark, or by omitting defective screening during the process, and then during the final measurement after the product was completed.

[Problem that the invention seeks to solve]

In this way, during laser trimming work, if the worker manually marks the defective parts every time the laser trimming process is completed on one board, the work efficiency will be significantly reduced. Occasionally, malfunctions such as erroneously marking good and defective products are unavoidable, and there is a risk that defective products may be mixed in with the products.

In order to prevent the occurrence of defective products, it is possible to put the laser-trimmed board through another special marking device, measure the resistance values of all blocks again, and mark the defective parts. According to the above method, there was a problem in that the measurement work was performed twice and the overall work efficiency was lowered, and the burden of process management such as the work of moving objects to dedicated equipment increased accordingly.

[Means for solving problems]

Therefore, in the present invention, the electrical characteristic values such as the resistance values of each of a plurality of blocks to be processed, which are arranged in squares in the XY direction on the substrate to be processed, are measured on the laser trimming table. While storing the position of the defective block in the storage means, the position of the defective block is stored by measuring the electrical characteristic value while laser trimming the good block on the board, and then the board after the laser trimming process is completed. This method employs a method in which the defective block is positioned and fixed on the table of the XY plotter, and a marker of the XY plotter is used to attach a mark for displaying the defective block location based on data from the defective block location storage means.

[Effect]

According to this method, by storing the measurement results of electrical characteristic values that are performed immediately before laser trimming, there is no need to perform unnecessary laser trimming on locations determined to be defective block locations, and during subsequent laser trimming. The measurement results performed at the same time and the previous results are stored in the storage means (thereby, these measurement results can be used as they are without wasting them, and the data can be retrieved and Since the plotter marks the defective block locations on the board, there is no need to measure the electrical characteristic values of the processed blocks again using the XY plotter, greatly improving work efficiency, and eliminating the need for laser trimming to locate defective block locations. The work up to the detection of defective products through marking can be integrated into a consistent assembly line process, contributing to labor savings through automated processing.

〔Example〕

To explain the embodiments below, 4. Figure 1 shows a block diagram of the entire apparatus for carrying out the method of the present invention. Central processing unit (CPU) that issues execution instructions, i
i is a laser beam generator; 12 is a beam positioner for focusing and positioning the laser beam from the generator 11 on a predetermined block 1' position on the substrate 1 to be processed; [13, 14 and a condenser lens]; 15 is not shown.

It is configured so that it can be moved to any X or Y position using a Y linear motor.

Reference numeral 16 denotes a measuring means for measuring electrical characteristic values such as resistance values at a large number of workpiece blocks 1' divided into squares in the X and Y directions on the substrate 1, and a device 16' in the measuring means 16.
A large number of probes 17, which are measurement probes, are arranged in parallel and movable up and down, and the block 1' to be processed is formed with a plurality of resistive elements 3 as shown in FIG. When there are many pieces to be measured per block to be processed or in the case of chip resistors, a predetermined number of probes 17 may be provided at predetermined positions in the X and Y directions, as many as are required for one block to be processed. , as shown in Figure 2, X, Y
A predetermined number of probes 17 may be provided so as to measure all the blocks to be processed in the X direction at once when a plurality of blocks to be processed are divided in that direction.

Reference numeral 18 denotes a table step movement mechanism that allows the substrate 1 placed on the table 19 to be moved stepwise in one direction or in both the X and Y directions in a predetermined position and position;
Reference numeral 20 denotes a transfer mechanism using vacuum suction or the like to transfer the substrate 1 onto the table 19, 21 a transfer mechanism using vacuum suction or the like to transfer the processed substrate 1 onto the table 23 in the XY block 22, and an XY plotter. 22 is a device that moves the pen 24 stepwise in the XY directions and then moves up and down so as to mark a predetermined location on the upper surface of the substrate l placed on the table 23 with the marker pen 24. A sub-processing unit is provided for storing data and executing instructions from storage means 27, 28 of the XY plotter 22, which is located adjacent to the table 19 in the laser trimming device. Further, 26 indicates an unloading mechanism using vacuum suction or the like for unloading the marked substrate 1 from the table 23 in the XY block 22;
27 and 28 are storage means, of which 27 stores the total number of each processing block, the number in both the X and Y directions, and the quality of the electrical characteristic values of the processing block, according to one type of size of the substrate 1 to be processed. This is a so-called read-only memory (ROM) in which command data for attaching an indicator 25 to the defective block location is specified based on comparison judgment data and defective block location recognition data described later, and 28 is a read-only memory (ROM) in which command data for attaching an indicator 25 to the defective block location is specified based on comparison judgment data and defective block location recognition data described later. This is a so-called random access memory (RAM) that makes a pass/fail judgment in the central processing unit 10 based on the measured value and the pass/fail judgment data in the storage means 27 and stores the position of the defective block.

FIG. 2 is a perspective view schematically showing the main equipment mentioned above.
On the substrate 1, there are 10 blocks 1' each in the X and Y directions.
In order to simplify the explanation, one measurement probe 17 is shown corresponding to each block to be processed.

Next, a method for laser trimming the substrate 1 and marking defective products using these devices will be described in detail with reference to the flowcharts shown in FIGS. 5 and 6.

FIG. 5 is a flowchart of the laser trimming process, and FIG. 6 is a flowchart of the marking process. A large number of substrates 1 are carried in a fixed direction (from a magazine (not shown), etc. stored in the figure) onto a table 19 of a laser trimming device using a carrying mechanism 20 such as a vacuum suction type, and placed on the table 19 of the laser trimming apparatus. The substrate 1 is fixed at a predetermined position from the origin of the X and Y axes.

The table 19 is moved step by step in the Y direction, and all the probes 17 in the measuring means 16 are lowered at the same time, and each tip is placed at a predetermined measurement position on the block 1' from Xl to XIG in the first row of Y. They are brought into contact and energized, and electrical characteristic values such as predetermined resistance values are measured all at once. When the resistance value is measured, if the resistance value of the resistor element 3 before laser trimming is outside a predetermined value range, it is determined to be defective. 1' is stored in the RAM storage means 28.

The beam positioner 12 moves the condensing lens 15 onto a portion of the block 1' that has passed and is not defective, and while the measurement means 16 measures, the portion irradiated with the laser beam 29 is moved to sequentially perform laser trimming. If a defect occurs due to failure during this laser trimming process, the result is also stored in the RAM storage means 28.

In addition, if there are multiple resistive elements 3 per block such as a resistor network, all of the multiple resistive elements 3 are measured before laser trimming, and if even one fails, If one entire block is defective, and even if one resistor element 3 fails during laser trimming, the entire one block will be defective.

After laser trimming the block 1' containing only non-defective products from Xl to
direction, and repeat the steps of measurement, storage, laser trimming, and storage for the second Y row.

Upon determining that the processing for one board 1 has been completed, that is, the processing for the first to tenth columns of Y in the board shown in FIG. After the data is sent to the XY plotter 22 and stored in the storage means in the XY plotter 22, the storage in the RAM storage means 28 is cleared (erased).

If both of the judgments are YES from the judgment of whether the marking work has been completed by the XY plotter 22 in the subsequent process and the judgment of whether the substrate 1 after the marking process has been carried out from the table 23 by the carry-out mechanism 26, the judgment is YES. , the substrate 1 is transferred from the table 19 to the table 23 by the transfer mechanism 21.
On the other hand, a new substrate 1 is carried onto the table 19 in the laser trimming apparatus, and the above-mentioned processing steps in the laser trimming apparatus are repeated.

On the other hand, the XY plotter 22 receives the data on the position of the defective block in the RAM storage means 28, and the table 2
3, the board 1 is fixed at a predetermined position corresponding to the origin of the X-axis and Y-axis, and then the data of the defective block location and the marking position coordinates (type, size of the board 1 The sub-processing device in the XY plotter 22 calculates the plotting position by the marker pen 24 based on the position coordinates for marking the specified position of each defective block location. In response to this calculation signal, the stepping motors in the X and Y directions of the XY plotter 22 are sequentially driven to horizontally move the sliders in both the X and Y directions, and each time they reach a predetermined marking position in a predetermined defective block location. marker pen 24
is lowered and a mark ta25 indicating that it is defective is placed at the predetermined position.

When this marking work is completed, a signal to that effect is sent to the central processing unit 10, and the substrate 1 is carried out from the table 23 via a vacuum suction type or other carrying out mechanism 26 according to a command from the unit 10.

In the above embodiment, all the applied blocks for one row of Y were measured at the same time, and the table 19 was also configured to move intermittently only in the Y direction. Alternatively, the table 19 may be configured to be able to move stepwise in both the X and Y directions in order to measure a plurality of items.

〔Effect of the invention〕

In this way, according to the present invention, by storing the measurement results of electrical characteristic values that are performed immediately before laser trimming, there is no need to perform unnecessary laser trimming on locations determined to be defective block locations. You can improve efficiency. By storing the measurement results before the laser trimming process and the measurement results performed simultaneously with the subsequent laser trimming process in the storage means, these measurement results can be saved without being wasted. Data can be used as is. In other words, if an already processed substrate is placed in the same positional relationship as in the laser trimming device in the XY block that has received the data of the defective block location, the positional coordinates of the defective block location will be the same in both, so By using the data on the defective block location as is, it is possible to mark the defective block location on the board. Therefore, with the XY block, it is possible to omit the need to measure the electrical characteristic values of the processed block again, greatly improving the work efficiency for marking. Since the masking work can be performed almost in parallel, the work from laser trimming to defective product detection by marking defective block locations can be integrated into a consistent assembly line, contributing to labor savings through automated processing. This has the effect of improving the reliability of the final product by eliminating manual errors.

[Brief explanation of drawings]

The drawings show embodiments of the present invention; FIG. 1 is a block diagram of an apparatus for carrying out the method of the present invention, FIG. 2 is a perspective view of the main parts thereof, and FIG. 3 is a plan view of the main parts of the substrate. , FIG. 4 is a plan view of the resistor network, FIG. 5 is a flowchart of the laser trimming process, and FIG. 6 is a flowchart of the marking process. 1... Board, 1'... Block, 3... Resistance element, 10... Central processing unit, 11... Laser beam generator, 12... Beam positioner, 29
... Laser beam, 16... Measuring means, 17...
... Probe, 18... Table movement mechanism, 19.
...Table, 20...Carrying mechanism, 21...
Transfer mechanism, 22...XY plotter, 23...table, 247-capen, 25...marker, 26...
...Export mechanism, 27...Storage means, 28...Storage means.

Claims (1)

[Claims] (1) On the laser trimming table, measure the electrical characteristic values such as the resistance value of each of the plurality of blocks to be processed, which are arranged in squares in the X and Y directions on the substrate to be processed. While the block location is stored in the storage means, the defective block location is stored by measuring the electrical characteristic value while laser trimming the good block location on the board, and then the board after the laser trimming process is The defective block in the laser trimming processing process is characterized in that the XY plotter is positioned and fixed on a table of a plotter, and a marker of the XY plotter is used to attach a mark for displaying the defective block location based on data from the defective block location storage means. Marking method for non-defective products.