KR101148669B1 - The apparatus for testing the substrate - Google Patents

Abstract

The present invention relates to an inspection apparatus for inspecting an electrical pattern state of a substrate, and in particular, a clamp for supporting a printed circuit board; A plurality of pins attached to each point of the chip mounted on the printed circuit board to apply current; A current supply unit electrically connected to the clamp and the plurality of pins to supply a current; And a metal tag attached to the clamp and in contact with the bottom surface of the supported printed circuit board, in particular including a metal tag attached to the clamp, thereby applying a current to the lower surface of the substrate to directly below the chip. The present invention relates to an apparatus capable of detecting a short defect caused by foreign matter on a face.

Description

Substrate Inspection Device {THE APPARATUS FOR TESTING THE SUBSTRATE}

The present invention relates to an inspection apparatus for inspecting an electrical pattern state of a substrate, and in particular, a clamp for supporting a printed circuit board; A plurality of pins attached to each point of the chip formed on the printed circuit board to apply current; A current supply unit electrically connected to the clamp and the plurality of pins to supply a current; And a metal tag attached to the clamp and in contact with the bottom surface of the supported printed circuit board, in particular including a metal tag attached to the clamp, thereby applying a current to the bottom surface of the substrate to directly below the chip. The present invention relates to an apparatus capable of detecting a defect in a current supply unit due to foreign matter on a surface.

With the development of the electronics industry, the demand for printed circuit boards for mounting electronic components such as ICs (Integrated Circuits) and LSIs (Large Integrated Circuits) increases rapidly, and miniaturization and high functional electronic devices are required. The conductor pattern of densification is increasing. It refers to an electrical wiring diagram formed of an electrically conductive metal on at least one of the outer layer or the inner layer of this printed circuit board or generally an electrically insulating substrate.

In such a printed circuit board, if there is a defect (defect) such as a short circuit or a disconnection in the conductor pattern, the reliability of the product quality is remarkably impaired. Therefore, it is common to inspect the defect of the substrate during manufacturing.

In order to detect defects that occur in the manufacturing process of a printed circuit board, it is generally possible to determine whether the circuit pattern is good using optics or to detect the open / short supply state of the circuit pattern by using electrical inspection. do. In addition, the appearance inspection is finally carried out to determine the quality.

In general, a method of manufacturing a printed circuit board, first, an insulating layer is formed on a base substrate, a copper foil is provided on one side of the insulating layer, and a photoresist is applied on the copper foil. Subsequently, exposure and development processes are performed and patterned, and a circuit pattern is formed by etching copper foil using this patterned layer as a mask. Subsequently, after performing a peeling process, an optical inspection (AOI) for determining the quality of the circuit pattern is performed, the printed circuit board judged as good quality is plated, and then a solder resist is applied. Electrically check open / current supply status. Then, finally, the appearance inspection is carried out to ship the good product.

In the optical inspection method, image data is acquired in pixel units which are the minimum units, and the widths of each pattern component and the spatial component are measured and compared with a reference value to determine good or bad. However, as the manufacture of ultrafine circuit patterns increases, an open or current supply portion having a width smaller than one pixel exists between the pixels and the pixels, and such defects cannot be detected by conventional optical inspection methods. Therefore, in order to detect the defect of the ultra fine circuit pattern, an electrical inspection process for detecting the open / current supply unit is performed in a subsequent process.

The electrical inspection process is typically a universal type for adjusting and inspecting each pin according to a PCB under test and a dedicated type for making and testing fixtures according to a model of the PCB under test. dedicated type).

The universal type is used in the most popular manner because the jig can be easily assembled by a method of contacting a pin on a basic grid. In addition, since semi-permanent recycling of pins is possible, the cost of fixtures is low, and there is an advantage of using the angle of the pin according to the PCB to be measured, but it is difficult to manufacture, the equipment itself is expensive, and generally 100mil or 70mil lattice It has a disadvantage that the ability to respond to high-density products is poor.

On the other hand, the manufactured type uses a dedicated inspection jig for the circuit of the substrate to be inspected. Since the probe pin is not recycled, the manufacturing cost of the jig is higher than that of the universal type, but the price of the facility itself is relatively low. It has a disadvantage in that it takes a lot of labor to manufacture because wire wrapping is required for each probe, but it is possible to inspect up to 14mil because of the vertical setting of the probe, and it has the advantage of good contact with the product. It is widely used for the inspection of mass production products.

The electrical inspection facilities are for cross-sectional product inspection, and because the pins for measuring the current supply portion are in contact with the chip mounting surface only and cannot be installed on the lower surface of the substrate, the current supply portion due to foreign matter between the chips. The defect can be detected, but there is a problem that the current supply failure due to the foreign matter on the substrate surface directly under the chip cannot be detected.

Therefore, it is necessary to modify the equipment so that the pins can contact the lower surface of the board, but there is a difficulty in changing the equipment. In a simpler manner, it is possible to detect a defect in the current supply caused by a foreign material on the board surface directly under the chip. There was a way to be.

The present invention has been made to solve the above problems, in particular a clamp for supporting a printed circuit board; A plurality of pins attached to each point of the chip mounted on the printed circuit board to apply current; A current supply unit electrically connected to the clamp and the plurality of pins to supply a current; And a metal tag attached to the clamp and in contact with the bottom surface of the supported printed circuit board, in particular including a metal tag attached to the clamp, thereby applying a current to the lower surface of the substrate to directly below the chip. It is an object of the present invention to provide a device capable of detecting a failure of a current supply unit by foreign matter on a surface.

The board inspection apparatus of the present invention for achieving the above object is a clamp for supporting a printed circuit board; A plurality of pins attached to each point of the chip mounted on the printed circuit board to apply current; A current supply unit electrically connected to the clamp and the plurality of pins to supply a current; And a metal tag attached to the clamp and in contact with the bottom surface of the supported printed circuit board.

Here, the metal tag may include a conductor.

Herein, the plurality of pins may include a controllable tilt angle of the chip.

Here, the display unit may further include a display unit for displaying the detected current supply unit to inform the user.

According to the present invention, by applying a current to the lower surface of the printed circuit board through the metal tag attached to the clamp, it is possible to detect a current supply failure by foreign matter on the substrate surface directly under the chip in a simple manner without any additional equipment modification. There is an effect.

1 is a conceptual diagram of a conventional substrate inspection apparatus.
2 is a conceptual diagram of a substrate inspection apparatus according to the present invention.
3 is a conceptual diagram illustrating whether or not inspection is possible by a conventional method when a short defect occurs.
4 is a conceptual diagram illustrating the inspection principle according to the present invention when a short defect occurs.

Hereinafter, preferred embodiments of the present invention will be described in detail so that those skilled in the art may easily implement the present invention.

Prior to this, the terms or words used in this specification and claims should not be limited to the usual or dictionary meanings, and the inventors will be required to properly define the concepts of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that it can.

Therefore, the configuration of the embodiments described herein is only one of the most preferred embodiments of the present invention and does not represent all of the technical idea of the present invention, various equivalents and modifications that can replace them at the time of the present application It should be understood that there may be

Hereinafter, the present invention will be described in more detail with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the concept of the conventional board | substrate inspection apparatus, and FIG. 2 is a figure which shows the concept of the board | substrate inspection apparatus by this invention.

As shown in FIG. 2, the apparatus for inspecting a substrate of the present invention includes a clamp 10 supporting a printed circuit board 1 and a plurality of pins attached to respective points of a chip mounted on the printed circuit board to apply current. 20, a current supply unit 30 electrically connected to the clamp 10 and the plurality of pins 20 to supply a current, and attached to the clamp 10 to be in contact with a lower surface of the supported printed circuit board. It is configured to include a metal tag 40.

Here, the metal tag 40 is preferably a conductor, because the current supply to the substrate can detect the failure of the current supply unit due to foreign matter on the substrate surface directly below the chip.

Here, the plurality of pins 20 may include a controllable angle of inclination of the chip. Although the plurality of pins 20 are embedded in the fixture, although not shown in the drawing, in detail, the body, the contact pins at both ends of the body, and the contact pins do not apply excessive force when they contact the PCB pattern. It consists of a built-in spring that acts as a buffer. Here, the upper tip portion of the contact pin is to be in contact with the copper foil or the chip of the PCB, and the overall characteristics of the substrate are examined by this configuration.

The fixture for mounting a plurality of contact pins is made of an insulating board such as acrylic, and is used to check characteristics of a printed circuit board on which a general component is mounted, not a surface mount device or an LSI device. The fixture is constructed by setting pin positions to check for open, short, insulation resistance, etc. on each pattern of the substrate, and then manually inserting contact pins by hole processing.

The apparatus of the present invention may further include a display unit which displays the position of the detected current supply unit and informs the user.

In contrast to FIG. 1 of the prior art, there is a difference in that it includes a metal tag 40 attached to the clamp 10 and in contact with the bottom surface of the supported printed circuit board.

Here, each of the pins 21, 22, 23, 24 in contact with the chip mounted on the substrate is made of a plurality of contact with the plurality of measuring points.

The present invention is distinguished from FIG. 2 of the prior art in that it includes a metal tag 40 attached to the clamp 10 and in contact with the lower surface of the supported printed circuit board 1, through the current supply 30 The current flows from the 10 to the metal tag 40 so that the current also flows to the substrate portion of the printed circuit board 1 in contact with the metal tag 40.

That is, as shown in Figure 3, when the current supply failure (A) caused by the foreign matter on the substrate surface directly below any chip, according to the prior art, each of the pins are connected in parallel, the current is applied to the substrate Because it does not flow, the short defect is not known at all.

However, as shown in FIG. 4, in the present invention, when a current supply failure A occurs due to a foreign material on the substrate surface immediately below any chip, the pins are connected in parallel with each other. Since the current flows from the clamp 10 to the metal tag 40 through the 30, the current also flows in the substrate portion of the printed circuit board 1 in contact with the chip 10, and thus the chip mounted on the portion where the short exists. Current flows between the pin 23 and the substrate in contact with each other, so that a defect in the current supply unit due to foreign matter on the substrate surface immediately below the chip can be detected.

Also, although not shown in FIGS. 2 and 4, a plurality of printed circuit boards are disposed in the clamp 10, and the printed circuit board 1 is automatically moved one by one, and the inspection is continued as the pins contact the next board. Proceed.

10: Clamp
20: pin
30: current supply unit
40: metal tag

Claims (4)

A clamp for supporting a printed circuit board;
A plurality of pins attached to each point of the chip mounted on the printed circuit board to apply current;
A current supply unit electrically connected to the clamp and the plurality of pins to supply a current; And
And a metal tag attached to the clamp and in contact with the bottom surface of the supported printed circuit board.
The method of claim 1,
And the metal tag is a conductor.
The method of claim 1,
The plurality of pins are substrate inspection apparatus comprising the adjustable angle of inclination with respect to the chip.
4. The method according to any one of claims 1 to 3,
And a display unit which displays a position of the detected current supply unit and informs the user.

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