JP2003273507A - Board mounting method for electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inspect printing condition of cream solder, and to take in board information on a mounting board by a simple structure at low cost. <P>SOLUTION: When a surface mounting board where cream solder is printed on a pad is transported, a camera 4 is moved and an image of a two-dimensional symbol that is formed on a certain region of a surface mounting board is taken in by the camera 4. Board ID information is read from the image by an image processing part 8 after a cut-out process of the two dimensional symbol. Continuously, the image of the surface mounting board is photographed by the camera 4, and the image processing part 8 inspects the printing condition of the cream solder on the pad from the image and determines the quality. After finishing all inspections, the board ID information of the inspected surface mounting board that is related with the inspection results is stored in a storage part of a quality information managing system JS. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting electronic parts on a board, and more particularly, to a print inspection of cream solder printed on an electrode portion of a printed wiring board for mounting a surface mounting type semiconductor part or the like. It relates to effective technology.

[0002]

2. Description of the Related Art A solder print inspection device is widely known as a device for inspecting print defects such as print misalignment, print bleeding, and print blur of cream solder printed on a mounting substrate on which surface mount components such as semiconductor devices are mounted. ing.

In recent years, in board assembly lines and the like,
Quality control information systems are being introduced to improve quality and productivity. In this quality control information system, information such as the inspection result in the solder printing inspection apparatus is indispensable as one of the information for controlling the quality.

According to a study made by the inventor of the present invention, a code reader or the like for reading a bar code or the like of a printed wiring board is separately attached to the solder printing inspecting apparatus in order to correspond to the above-mentioned system.

The solder printing inspection device associates the inspection result of the cream solder printing with the board information read by the code reader to generate quality control information, and outputs it to the quality control information system or the like.

As an example in which this type of surface mounting technology is described in detail, as an example, July 28, 2000, published by Industrial Research Institute Co., Ltd. Dictionary "P607-P6
11 and this document describes a solder printing technique.

[0007]

However, the present inventor has found that the technique for detecting defective solder paste printing in the above-described solder printing inspection apparatus has the following problems.

That is, when the code reader is separately attached to the solder printing inspection apparatus, there is a problem that purchase costs and attachment costs of the code reader are newly generated.

Further, the control of the cream solder inspection device and the control of the code reader must be linked, the control system becomes complicated, and new hardware such as an interface is required, so that the inspection cost and the like are significantly increased. There is a problem of doing.

Further, a space for mounting the code reader and a space for reading a bar code are required, which may hinder the downsizing of the cream solder inspection apparatus.

An object of the present invention is to provide a board mounting method for an electronic component capable of inspecting the printed state of cream solder and fetching board information in a mounting board with a simple structure at low cost. It is in.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0013]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

That is, according to the electronic component board mounting method of the present invention, cream solder is printed on a plurality of electrode portions formed on the mounting surface on which the electronic component is mounted, and a two-dimensional symbol is formed in an area on the mounting surface. A step of preparing a provided printed wiring board; a step of capturing the two-dimensional symbol by an image pickup means to read ID information of the printed wiring board; a step of capturing an image of an arbitrary electrode portion by the image pickup means; From the above, there is a step of determining whether the printed state of the cream solder printed on the electrode section is good or bad, and a step of associating the ID information and the determination result of the cream solder in the storage section.

Further, according to the electronic component board mounting method of the present invention, cream solder is printed on a plurality of electrode portions formed on the mounting surface on which the electronic component is mounted, and a two-dimensional symbol is provided in an area on the mounting surface. A step of preparing the provided printed wiring board, and a printed wiring board having any one or more of a lot number, a manufacturing date, a board identification number, a manufacturing factory, and a board type by taking in a two-dimensional symbol thereof by an imaging means. By the process of reading the ID information of
From the process of capturing an image of an arbitrary electrode part and the image,
The method includes a step of determining whether the printed state of the cream solder printed on the electrode portion is good or bad, and a step of associating the ID information and the determination result of the cream solder in the storage portion.

Further, in the electronic component board mounting method of the present invention, cream solder is printed on a plurality of electrode portions formed on the mounting surface on which the electronic component is mounted, and a one-dimensional symbol is provided in an area on the mounting surface. The step of preparing the provided printed wiring board, the step of capturing the one-dimensional symbol by the image pickup means and reading the ID information, and the step of the image pickup means
From the process of capturing an image of an arbitrary electrode part and the image,
The method includes a step of determining whether the printed state of the cream solder printed on the electrode portion is good or bad, and a step of associating the ID information and the determination result of the cream solder in the storage portion.

Further, according to the electronic component board mounting method of the present invention, cream solder is printed on a plurality of electrode portions formed on the mounting surface on which the electronic component is mounted, and a one-dimensional symbol is provided in an area on the mounting surface. The step of preparing the provided printed wiring board and the one-dimensional symbol thereof are captured by the image pickup means, and ID information having any one or more of a lot number, a manufacturing date, a board identification number, a manufacturing factory, and a board type is displayed. A step of reading, a step of capturing an image of an arbitrary electrode portion by an image pickup means, a step of determining the quality of the printed state of the cream solder printed on the electrode portion from the image,
And a step of storing the D information and the determination result of the cream solder in the storage unit in association with each other.

Further, according to the electronic component board mounting method of the present invention, cream solder is printed on a plurality of electrode portions formed on the mounting surface on which the electronic component is mounted, and a two-dimensional symbol is formed in an area on the mounting surface. A step of preparing the provided printed wiring board and the electronic component, a step of mounting the electronic component on the printed wiring board, taking in the two-dimensional symbol by an image pickup means, a lot number, a manufacturing date, and a board identification number. , A manufacturing factory, a step of reading ID information of a printed wiring board having one or more of board types, a step of capturing an image of the printed wiring board on which electronic components are mounted by an image pickup means, and an electronic image from the image. It has a step of visually inspecting the mounting state of the component and a step of associating the ID information and the inspection result with each other and storing them in a storage unit.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is an explanatory view showing the structure of a solder printing inspection apparatus according to an embodiment of the present invention, and FIG. 2 is an example of a two-dimensional symbol formed on a surface mount board according to an embodiment of the present invention. 3 is a flowchart showing a solder printing inspection process in the solder printing inspection apparatus of FIG. 1, and FIG. 4 is a flowchart of cutting processing of a two-dimensional symbol image captured by the solder printing inspection apparatus of FIG. .

In the present embodiment, the solder printing inspection apparatus 1 is an apparatus for inspecting print defects such as print misalignment, print bleeding, and print blur of cream solder printed on a mounting board on which surface mount components are mounted.

As shown in FIG. 1, the solder print inspecting apparatus 1 is provided with an inspecting conveyor 2 that conveys a surface mounting board (printed wiring board) to be inspected. The inspection control conveyor 2 is controlled by the transfer control unit 3.

A camera (imaging means) 4 is provided above the inspection conveyor 2. The camera 4 captures an image of an arbitrary area on the surface mount board and captures an image of the two-dimensional symbol SY shown in FIG. 2 formed in the arbitrary area of the surface mount board.

As a result, the structure and control system for reading the two-dimensional symbol SY can be simplified, and the solder printing inspection apparatus 1 can be downsized and the cost can be reduced.

The two-dimensional symbol SY is imprinted by irradiating a surface mounting board with a laser beam or the like, for example. Alternatively, a sticker or the like on which a two-dimensional symbol is printed may be attached to the surface mounting board.

The two-dimensional symbol SY is, for example,
It is composed of two-dimensional symbols whose specifications are standardized by the DataMatrix standard or the like. Here, the two-dimensional code is based on the DataMatrix standard.
The data code of the dimensional symbol SY may be another standard.

The board ID information (ID information) of the surface mounting board is written in the two-dimensional symbol SY. This board ID information is, for example, the lot number of the surface mounting board,
It includes at least one piece of history information such as the date of manufacture, the board identification number, the manufacturing factory, and the board type.

In addition, as shown in FIG.
An X-axis robot 5 and a Y-axis robot 6 are provided. The X-axis robot 5 is a mechanism that moves the camera 4 in the X (horizontal) direction, and the Y-axis robot 6 moves the camera 4 in the Y direction.
It is a mechanism to move in the (lateral) direction.

The X-axis robot 5 and the Y-axis robot 6
A robot controller 7 is connected to each. The robot controller 7 controls the operation of the X-axis robot 5 and the Y-axis robot 6 based on the input position control information.

Further, an image processing section 8 is connected to the camera 4. The image processing unit 8 performs image processing on the image of the surface mounting board captured by the camera 4 and the image of the two-dimensional symbol SY, and performs inspection determination of cream solder printing, reading information on the two-dimensional symbol SY, and the like.

The transfer controller 3, the robot controller 7,
In addition, the overall control unit 9 is connected to the image processing unit 8. The overall control unit 9 uses the solder printing inspection device 1
Control all of the.

A quality information management system JS for managing the manufacturing process and quality of the product is connected to the solder printing inspection device 1, and the inspection result of each surface-mounted board via the overall control unit 9 And the board ID information is transmitted.

Next, the operation of the solder print inspection apparatus 1 in this embodiment will be described with reference to the flowchart of FIG.

First, the surface mount board to be inspected is conveyed to the proper position by the inspection conveyor 2 (step S101). In this surface mount board, cream solder is printed on each pad in the previous step, and a two-dimensional symbol SY is applied to an area on the mount surface by laser light or the like.
Is engraved.

When the overall controller 9 detects that the surface mount board has been conveyed through the board detecting sensor, the position of the surface mount board is recognized based on the alignment mark data for detecting the board position, and the surface mount board is detected. Understand the amount of misregistration.

After that, position control data is generated based on the inspection data stored in advance in the memory of the overall control unit 9 and output to the robot controller 7. The robot controller 7 receives the position control data and controls the X-axis robot 5 and the Y-axis robot 6 respectively to control the camera 4
Is moved (step S102), and the image of the two-dimensional symbol SY formed in a certain area of the surface mount substrate is captured by the camera 4 (step S103).

The captured image of the two-dimensional symbol SY is output to the image processing unit 8, and the image processing unit 8 outputs 2
Substrate ID after cutting out the dimension symbol SY
Information is read (step S104).

Now, the process of cutting out the two-dimensional symbol SY by the image processing unit 8 will be described with reference to the flowchart of FIG.

First, the two-dimensional symbol SY is displayed in the image processing unit 8.
When the image is captured, it is determined whether the image is reversed (step S201). This step S
When the image is inverted in the process of 201, the look-up table is converted (step S202).
The conversion of the look-up table is a process of reversing the reflectance of an image so that an image with a black background or a white background can be read.

After the processing of step S202 or when the image is not inverted in the processing of step S201, the brightness distribution is obtained in order to make the image a binary (black and white) image, and the binarization is automatically performed. The threshold value for performing is acquired (step S203).

After that, noise reduction processing that differs depending on the brightness level of the image is performed, and brightness / darkness filtering processing that equalizes the black and white level is performed (step S204), and the automatic binarization threshold value is acquired again (step S205). Is binarized (step S206).

A binary projection distribution is obtained from the entire binarized image or a designated area, the distribution range of the pattern of the two-dimensional symbol SY is specified (step S207), and the position pattern is detected (step S208).

This clearly identifies the position and direction of the symbol. If one pattern cannot be detected in the process of step S208, step S2
The processing from 01 is executed again.

Subsequently, as shown in FIG. 2, when the image is captured while being inclined, the rotation angle of the image is corrected (step S209), and the two-dimensional code distribution range is specified again (step S210). ), The position pattern is detected again (step S211).

Then, a module pattern in which light and dark are alternately arranged with a certain width in the horizontal direction and the vertical direction is detected, and the number of modules in the horizontal direction and the vertical direction, the module position, etc. are determined (step S2
12).

After that, the number of modules detected by the process of step S212 and the module position are checked to see if the symbol is a valid symbol (step S213), and then the reading process is performed.

Then, as shown in FIG.
Generates position control data based on the inspection data, and the robot controller 7 causes the X-axis robot 5 and Y to move.
The axis robots 6 are controlled to move (step S10).
5) The camera 4 captures and captures an image of the inspection area on the surface-mounted substrate, and outputs the image to the image processing unit 8 (step S106).

Then, the image processing section 8 inspects the print state of the cream solder of each pad formed on the surface mounting board based on the inspection information output from the overall control section 9 to determine whether it is good or bad ( Step S107).

In the process of step S107, the area of the cream solder printed on the pad to be inspected and the area of the pad exposed from the cream solder are obtained from the captured image, and the area and the pass / fail judgment threshold value are obtained. Is compared to determine whether or not the printed state of the cream solder printed on the pad is good.

The processing of these steps S105 to S107 is repeated until the inspection of solder printing on the entire surface mounting substrate is completed (step S108).

After the inspection of all the pads is completed, the overall control section 9 outputs a conveyance permission signal to the conveyance control section 3 to operate the inspection conveyor 2 and conveys the surface-mounted board to the next step (step). S109).

The overall controller 9 associates the board ID information of the inspected surface-mounted board and the inspection result with each other and outputs them to the quality information management system JS (step S110). The input board ID information and inspection result are stored in a storage unit or the like provided in the quality information management system JS. The board ID stored in the quality information management system JS
Information and inspection results are used for quality control and failure analysis.

Therefore, according to the present embodiment, by providing the function of reading the information of the two-dimensional symbol SY, the cost of the solder printing inspection apparatus 1 can be reduced and the size can be reduced.

Further, in the present embodiment, the board ID
Although the information is written in the two-dimensional symbol, the substrate ID information may be written in the one-dimensional symbol such as a barcode.

Although the invention made by the present inventor has been specifically described based on the embodiments of the present invention, the present invention is not limited to the above-mentioned embodiments, and various modifications are possible without departing from the scope of the invention. It goes without saying that it can be changed.

Further, in the above-described embodiment, the solder printing inspection apparatus is provided with the function of reading the information of the two-dimensional symbol. However, for example, the mounting for inspecting the mounting state of the electronic component mounted on the surface mounting board is mounted. The present invention can be applied to a substrate visual inspection device or other visual inspection device having an image pickup means for capturing an image for inspection.

[0057]

The effects obtained by the typical ones of the inventions disclosed in this application will be briefly described as follows.
It is as follows.

(1) By reading the image of the two-dimensional symbol by using the image pickup means for taking in the image for solder printing inspection, a new mechanism for reading the two-dimensional symbol can be eliminated.

(2) Further, due to the above (1), the cost and size of the solder printing inspection device can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of a solder printing inspection apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a two-dimensional symbol formed on a surface mount board according to an embodiment of the present invention.

3 is a flowchart showing a solder print inspection process in the solder print inspection apparatus of FIG.

FIG. 4 is a flowchart of a cutout process of a captured two-dimensional symbol image by the solder printing inspection apparatus of FIG.

[Explanation of symbols]

1 Solder printing inspection device 2 Conveyor for inspection 3 Transport control unit 4 cameras (imaging means) 5 X-axis robot 6 Y-axis robot 7 Robot controller 8 Image processing unit 9 Overall control unit SY two-dimensional symbol JS Quality Information Management System

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G06T 1/00 305 G06T 1/00 305A H05K 1/02 H05K 1/02 R (72) Inventor Jun Higuchi Gunma Gunma 1-F, Nishiyote-cho, Takasaki-shi, F-term, Hitachi Eastern Semiconductor Co., Ltd. GG15 5E338 CC09 DD22 DD32 EE31 EE33 EE51

Claims (5)

[Claims] 1. A step of preparing a printed wiring board in which cream solder is printed on a plurality of electrode portions formed on a mounting surface on which an electronic component is mounted, and a two-dimensional symbol is provided in a region on the mounting surface. A step of taking in a two-dimensional symbol of the printed wiring board by an image pickup means and reading ID information of the printed wiring board; and a step of taking an image of an arbitrary electrode part on the printed wiring board by the image pickup means, And a step of determining whether the printed state of the cream solder printed on the electrode section is good or bad from the captured image, and a step of storing the ID information and the determination result of the cream solder in a storage section in association with each other. A method for mounting an electronic component on a substrate, comprising: 2. A step of preparing a printed wiring board in which cream solder is printed on a plurality of electrode portions formed on a mounting surface on which an electronic component is mounted, and a two-dimensional symbol is provided in a region on the mounting surface. The two-dimensional symbol of the printed wiring board is captured by the image pickup means, and lot number, manufacturing date, board identification number,
A step of reading ID information of the printed wiring board having at least one of a manufacturing plant and a board type; a step of capturing an image of an arbitrary electrode part on the printed wiring board by the image pickup means; and the captured image From the above, there is a step of determining whether the printed state of the cream solder printed on the electrode section is good or bad, and a step of storing the ID information and the determination result of the cream solder in a storage section in association with each other. Substrate mounting method for electronic components. 3. A step of preparing a printed wiring board in which cream solder is printed on a plurality of electrode portions formed on a mounting surface on which an electronic component is mounted, and a one-dimensional symbol is provided in a region on the mounting surface. A step of taking in a one-dimensional symbol of the printed wiring board by an image pickup means and reading ID information of the printed wiring board; and a step of taking an image of an arbitrary electrode part on the printed wiring board by the image pickup means, A step of determining whether the printed state of the cream solder printed on the electrode section is good or bad from the captured image, and a step of storing the ID information and the determination result of the cream solder in a storage section in association with each other. A method for mounting an electronic component on a substrate, comprising: 4. A step of preparing a printed wiring board in which cream solder is printed on a plurality of electrode portions formed on a mounting surface on which an electronic component is mounted, and a one-dimensional symbol is provided in a region of the mounting surface. And, the one-dimensional symbol of the printed wiring board is captured by the image pickup means, and the lot number, the manufacturing date, the board identification number,
A step of reading ID information of the printed wiring board having at least one of a manufacturing plant and a board type; a step of capturing an image of an arbitrary electrode part on the printed wiring board by the image pickup means; and the captured image From the above, there is a step of determining whether the printed state of the cream solder printed on the electrode section is good or bad, and a step of storing the ID information and the determination result of the cream solder in a storage section in association with each other. Substrate mounting method for electronic components. 5. A printed wiring board in which cream solder is printed on a plurality of electrode portions formed on a mounting surface on which an electronic component is mounted, and a two-dimensional symbol is provided in a region on the mounting surface, and the electronic component. And a step of mounting the electronic component on the printed wiring board, a two-dimensional symbol of the printed wiring board is captured by an imaging means, and a lot number, a manufacturing date, a board identification number,
A step of reading ID information of the printed wiring board having at least one of a manufacturing plant and a board type; a step of capturing an image of the printed wiring board on which the electronic component is mounted by the image pickup means; A board for an electronic component, comprising: a step of performing a visual inspection of the mounted electronic component from an image; and a step of storing the ID information and an inspection result of the printed wiring board in a storage unit in association with each other. How to implement.