JPH0789126B2 - Method for testing electrical characteristics of hybrid integrated circuit board - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for inspecting the electrical characteristics of a hybrid integrated circuit board using a leadless probe card in an in-circuit tester for a hybrid integrated circuit, More specifically, it relates to a method for inspecting the electrical characteristics of a hybrid integrated circuit board, which can be performed before or after die bonding or wire bonding in forming a hybrid integrated circuit.

[Prior Art] A hybrid integrated circuit is one in which semiconductor components and passive components are mounted on an insulating substrate to form an electronic circuit, and this is packaged to handle the whole as one component. In the case of manufacturing such a hybrid integrated circuit, it is necessary to perform an electrical inspection in an intermediate stage before the whole is packaged, that is, in the manufacturing process of the hybrid integrated circuit. That is, after circuitization design, hybrid IC design, pattern design, screen fabrication, substrate process, etc., the circuit board is electrically inspected, and then wire bonded,
Further inspection is performed, and then the substrate mountain process is started. In the electrical inspection of this circuit board, for example, the electrical inspection of a thick-film or thin-film board is performed before die-bonding or wire-bonding (eg, assembling) chip components such as ICs to the board. In this way, it is possible to determine whether the cause of the failure that occurred after assembly was due to the board that occurred before assembly, or whether it occurred after assembly.
It is being repaired.

Conventionally, such electrical inspection of the board before and after assembly is
As shown in FIG. 6, the lead probe 25 is in contact with a required measurement point of the substrate 11 to inspect, but in this case, the lead probe 25 can be accurately measured at an arbitrary measurement point of the measurement object. Was positioned and fixed on the probe card.

In an inspection performed using such an apparatus, an inspection using an external lead pin or lead terminal can be easily performed, but an internal arbitrary point is used, so-called electrical information such as voltage and current For the measurement, a method is taken to make the inspection as easy as possible by bringing a lead probe into contact with the internal point or connecting a wire to an empty pin of the external pin in advance.

In addition, the multifunctionalization, combination, and high performance of electronic equipment such as OA equipment, communication equipment, consumer equipment, and industrial equipment are promoted,
According to this, as the circuit becomes larger in scale, and it becomes an analog-digital mixed circuit, etc., the in-circuit tester, the in-circuit emulator, etc. are used to inspect each module inside the circuit and its part is removed. Inspection to confirm the operation of the motherboard is an important means during development and design.

Under such circumstances, the microfilm of Japanese Utility Model Laid-Open No. 61-179747 describes a probe card having bumps, which is used in the electrical characteristic inspection of a semiconductor wafer after pellet formation. The characteristic test used is a method in which the pellet wafer is subjected to a characteristic test by closely adhering it to a support through a cushioning material such as a rubber-like sheet.This makes the front and back surfaces of the probe card uniform and parallel to the pellet wafer. It has been shown that it is possible to prevent a partial contact failure of the conductive contact.

[Problems to be Solved by the Invention] However, in the case of using the lead probe as described above, it is not only difficult to raise the probe when aligning the measurement point with the lead probe, There is a problem that it takes time.

Further, in recent hybrid integrated circuits, there are many problems that it is difficult to switch from one model to another because it is often produced in small lots of various types, and it is necessary to pay attention to the place for storing the prober and the protection of the tip of the probe during storage.

Further, as described in the microfilm of Japanese Utility Model Laid-Open No. 61-179747, a probe card for inspecting the electrical characteristics of a semiconductor wafer is a circuit having so-called unevenness in which components are mounted on the surface such as a hybrid integrated circuit board. It is unsuitable for the electrical characterization of plates and is virtually impossible to measure.

When using the lead probe type for inspection of ever-larger scale circuits and mixed analog / digital circuits, be careful of the place where the prober is stored and the tip of the probe during storage in order to support a wide variety of small quantities. In addition, there is the inconvenience that an in-circuit tester for inspecting such a hybrid integrated circuit is not yet on the market.

Therefore, the present inventor has conducted various studies on the above-mentioned problems, and as a result, by using a probe card in which bumps are formed corresponding to the measurement points of the object to be measured and by using a soft rubber-like body for the holding jig. The inventors have found a method in which these bumps are in close contact with the uneven surface of the hybrid integrated circuit board to prevent defective contact, and the present invention has been made based on this finding.

Therefore, it is an object of the present invention to provide a method of inspecting an electric characteristic of a hybrid integrated circuit board, which allows an accurate, quick and easy inspection using a leadless probe card.

[Means for solving problems]

The object of the present invention is to provide a method for electrically inspecting a hybrid integrated circuit board having surface irregularities by using a leadless probe card in an in-circuit tester for hybrid integrated circuit, wherein the leadless probe card is the hybrid integrated circuit. A flexible film having bumps corresponding to the electrical measurement points of the board, and the bump side of the leadless probe card is faced to the entire hybrid integrated circuit board having the unevenness on the component mounting side, and then the bump side This is achieved by a method of electrically inspecting a hybrid integrated circuit board having unevenness by pressing the entire surface opposite to the surface with a soft rubber-like holding jig.

Next, an embodiment of the present invention will be described more specifically with reference to the drawings, but this is an example and the present invention is not limited thereto.

As the substrate used in the present invention, a printed substrate, a flexible substrate, or the like is used, and either a thin film substrate or a thick film substrate may be used.

Table-1 shows the manufacturing process of the hybrid integrated circuit used in the present invention. The circuit design, the hybrid IC design and the pattern design are followed by the screen fabrication. Between the pattern design and the screen fabrication, Create a leadless probe card.

Here, in the leadless probe card, an inspection pattern is formed. For example, a bump is formed at a position corresponding to an electrical measurement point of a product circuit pattern. Then, the bumps are connected to each other and then the bumps are formed at the bump positions by soldering or the like.

Then, there is a substrate process, in which a circuit is formed on the substrate, and then electrical inspection of this substrate is performed using a leadless probe card. After board inspection, chip components such as ICs are die-bonded, and electrical inspection is performed after mounting the chip components after die-bonding. After that, after wire bonding, after performing the substrate mountain process,
Perform inspection before and after sealing.

FIG. 1 (a) is a front view of a thick film multilayer substrate die-bonded with each chip component, and FIG. 1 (b) corresponds to the measurement points of the thick film multilayer substrate of FIG. 1 (a). It is a front view of the leadless probe card which has a bump in a position.

In FIG. 1 (a), reference numeral 1 denotes a thick film multi-layer substrate, on which various chip components and passive components such as capacitors are mounted. Specifically, 2 is a VLSI chip, 3 is an LSI chip, 4 is an MSI chip, 5 is a transistor, 6 is a bare chip such as a diode, and 7 is a chip capacitor. 8 is a pad and 9 is a bonding wire.

In FIG. 1 (b), 11 is a leadless flexible probe card substrate, and 10 is a bump. This substrate has a connector projection pattern for connecting to a measuring instrument, and the bump 10 is connected to this connector projection pattern.

FIG. 2 is for explaining another embodiment of the leadless probe card of the present invention, and FIG. 2 (a) is an object to be measured for measurement using the leadless probe card of the present invention. Is a thick film substrate that is 3 x 3 inches and has a thickness of 0.63
It is a 5 mm one, and there are 12 circuit patterns in it.
Reference numeral 1 is one circuit board, and 1'is a board having a scribe line 16.

FIG. 2 (b) is a front view of the leadless probe card 11, 10 is a measurement bump formed on one circuit board, 13 is an alignment pattern, and 14 is for fixing the probe card. It is a screw hole. 12 is a connector part,
It is connected to the connector of the measuring instrument. Reference numeral 15 is a lead conductor.

As shown in FIG. 3, the structure of the bump 10 is formed at the point of the conductor surface 17 by soldering or the like. Also, the bumps may be formed of another conductor material.

As the leadless probe card of the present invention, a symmetrical pattern of the object to be measured is formed. Alternatively, a number of other objects to be measured may be collected and formed on one substrate to form another test pattern. Good.

Next, a measuring method using the leadless probe card of the present invention will be described. Basically, the inspection device shown in FIG. 4 is used. In this inspection apparatus, a table 19 is supported on a table 20, and a vacuum tube 21 is provided at the center. The thick film substrate 1, which is the object to be measured, is fixed on the stage 19 by vacuum, and the stage 19 mechanically moves up and down, left and right, and front and back. The amount of movement is accurately adjusted by the computer and adjusted to the measurement point of the leadless probe card 11. Further, the leadless probe card 11 is connected to the connector 18 and coupled to the measuring device. This inspection device can be used by applying a laser trimmer for laser trimming of a substrate. The method of attaching the prober differs depending on the model of the laser trimmer, but in the present invention, a leadless probe card adapted to this can be manufactured at a low price.

A measuring method using this inspection apparatus is shown in FIG.

FIG. 5 (a) shows a case where the entire inspection is performed in the board inspection, and shows the entire inspection including the chip components 2 and 3 mounted on the hybrid integrated circuit substrate 1, in which the mounted component has a slight step. Therefore, by pressing from the back surface of the leadless probe card 11 with a soft rubber-like holding jig 23, the leadless probe card 11 is pressed according to the step. That is, since the surface of the rubber-like body of the holding jig 23 can be deformed along the unevenness of the surface of the hybrid integrated circuit board by pressing, contact failure is caused even when applied to the hybrid integrated circuit board having such unevenness. It can make sufficient contact without causing.

5 (b) and 5 (c) are schematic sectional views showing an electrical inspection method for a hybrid integrated circuit board having circuits on both sides, and the substrate 31 is a double-sided circuit board on which components are mounted. In FIG. 5 (b), the electrical characteristics test can be performed by bringing the leadless probe card 11 into contact with both surfaces of the substrate in the same manner as in FIG. 5 (a). Further, FIG. 5 (c) is another embodiment of FIG. 5 (b), in which the leadless probe card 11 is brought into contact with one surface and the conventional lead probe 25 is electrically used on the other surface. It is a method of conducting an inspection.

The leadless probe card manufacturing method of the present invention can use any thick film technology known before this application. Known materials and materials are used for the production.

[Operation and Effect of the Invention] According to the present invention, a leadless probe card is used to oppose and match the entire hybrid integrated circuit board, and then the entire surface opposite to the bump side is pressed by a soft rubber-like holding jig. By doing so, it is possible to perform electrical characteristic inspection of the hybrid integrated circuit board having unevenness using the leadless probe card, and it is possible to perform the test accurately and quickly and easily. .

[Brief description of drawings]

FIG. 1 (a) is a front view of a thick film multilayer substrate die-bonded with each chip component, and FIG. 1 (b) corresponds to the measurement points of the thick film multilayer substrate of FIG. 1 (a). It is a front view of the leadless probe card which has a bump in a position. Further, FIG. 2 is a front view showing another embodiment of the leadless probe card of the present invention, and FIG. 2 (a) is a front view showing a thick film substrate as an object to be measured. Also, FIG. 2 (b)
[Fig. 4] is a front view of another leadless probe card. FIG. 3 is a sectional view showing a bump used in the present invention. FIG. 4 is a perspective view showing an inspection device used in the present invention. FIGS. 5A to 5C are cross-sectional views showing an embodiment measured using the leadless probe card of the present invention. FIG. 6 is a sectional view showing a state where a hybrid integrated circuit is measured using a conventional lead probe. Explanation of code 1 …… Thick film multilayer substrate 2 ～ 6 …… Bare chip parts 7 …… Chip capacitor, 8 …… Bonding pad 9 …… Wire, 10 …… Pad 11 …… Leadless probe card 12 …… Connector protrusion 13 …… Alignment pattern 14 …… Screw hole, 15 …… Lead 16 …… Scribe line, 17 …… Conductor 18 …… Connector, 19 …… Loading table 20 …… Table, 21 …… Vacuum tube 22 …… Part Pressing jig 23 …… Overall pressing jig 24 …… Base material, 25 …… Lead probe 111 …… Hard base material 112, 113 …… Convex part 31 …… Parts mounting double-sided circuit board

Claims (1)

[Claims] 1. A method for electrically inspecting a hybrid integrated circuit board having surface irregularities by using a leadless probe card in a hybrid integrated circuit in-circuit tester, wherein the leadless probe card is the hybrid integrated circuit board. The bump side of the leadless probe card, which is made of a flexible film having bumps corresponding to the electrical measurement points, is faced to the entire hybrid integrated circuit board having irregularities on the component mounting side, and then the bump side is A method of electrically inspecting a hybrid integrated circuit board having unevenness by pressing the entire opposite surface with a soft rubber-like holding jig.