JPH01268191A - Inspecting method for wiring net of ceramic board - Google Patents

Abstract

PURPOSE:To simplify an inspection of a wiring net by proving of one side face of a board, and to simultaneously inspect a disconnection and a short-circuit by circuit-connecting a terminal of one side face of the board through a resistor to the terminal of a power source conductor, and probing a power conductor of other face and the terminal of other conductor to read a resistance value. CONSTITUTION:A ceramic board 1 is composed of insulating layers 2a to 2d, power source conductors 3a to 3c, input/output signal conductors 3d, 3e, and terminals 4a to 4g, 5a to 5d. Then, the terminals 5a to 5d of the rear face 1b of the board 1 are connected by a circuit 9 having a resistor 8. Probes 6, 7 are, for example, brought into contact with the terminals 4a, 4c on the surface 1a of the board 1 in this state for measurement of a resistance value by an inspecting machine 10. Thus, the conductor 3b and other conductor 3d are electrically connected to the machine 10 through a circuit 9 having the resistor 8, thereby simultaneously inspecting both the conductors 3b and 3d. When the intersection P1 or P2 of conductor 3d and the conductor 3a or 3b is short- circuited, the resistor 8 is made in a state of a parallel connection, its value is reduced, thereby inspecting the short-circuit with a power source.

Description

[Detailed Description of the Invention] [Summary] Regarding an inspection method for inspecting disconnections and short circuits of wiring nets on a multilayer ceramic substrate used for printed boards after firing and lamination, the wiring net is inspected by probing one side of the board. For the purpose of simplifying the test and simultaneously inspecting disconnections and short circuits, the power supply and other conductor terminals on one side of the ceramic board are
The circuit is connected through a resistor, and the power supply and other conductor terminals on the other side of the ceramic substrate are probed to check for disconnections and shorts based on the resistance value.

[Industrial application field]

The present invention relates to an inspection method for inspecting disconnections and short circuits in wiring nets of a multilayer ceramic substrate used in a printed board after firing and lamination.

In recent years, there has been a significant demand for higher densities and higher speeds in mounting printed circuit boards, and one way to counter this is to increase the number of layers in the board. Materials for highly multilayered boards are required to have small dimensional changes and warpage, good electrical and thermal properties, small thermal expansion, and excellent soldering heat resistance, and are advantageous in this respect. There are high expectations for the practical use of ceramics in place of materials.

Various methods have been proposed for multi-layering ceramic substrates, among which the lamination method prints a conductor pattern on the insulating layer of a green sheet, stacks these in layers, presses them together, and fires them. Laminated on. Therefore, unlike organic substrates, this ceramic ink substrate does not have wiring lines formed by through holes penetrating all layers.

For this reason, through holes cannot be used to inspect the wiring net after lamination using a probe, and a new inspection method is required to be established.

[Conventional technology]

Therefore, conventionally, the wiring net inspection of the ceramic substrate is carried out as shown in FIG. That is, in the ceramic substrate 1, for example, four ceramic insulating layers 2a to 2d are laminated, and a conductive pattern is provided between each layer by filling vias with conductive paste. Here, insulating layer 2
A power supply conductor 3a is installed between c and 2d, conductors 3b and 30 are connected to this conductor 3a, and conductors 3d and 3d are not connected.
3e is exposed on the front surface]a and the back surface 1b of the substrate 1.

Each conductor 3b to 3e is connected to a terminal 4a to 4g of each integrated circuit component on the front side 1a, and to a terminal 5a to 5d of each input/output bin on the back side 1b.

Therefore, in the ceramic substrate 1, a probe 6.7 is placed in contact with the terminal 4c on the front surface 1a and the terminal 5a on the back surface 1b.
Conductor 3b is inspected for disconnection. Hereafter, each conductor 3
No wiring for c or 3e.

This test is performed by probing and inspecting the target.

[Problems to be Solved by the Invention] By the way, according to the above conventional inspection method, the probe 6.
7 is placed in contact with both surfaces 1a, ]b of the substrate 1, the mechanism of the inspection machine becomes complicated. Furthermore, the inspection time becomes longer due to the time required to move the two probes 6 and 7. On the other hand, there is a problem that such blowby can only test for disconnection, and cannot test for wire breaks between nets or between conductors.

The present invention was made in view of such problems, and includes:
The purpose of this is to simplify the inspection of wiring nets by blowing one side of the board, and to simultaneously inspect wiring nets on ceramic substrates for disconnections and short circuits.
1. To provide an inspection method.

[Failure to solve the problem]

In order to achieve the above object, the inspection method of the present invention utilizes the power supply conductor exposed on the front and back surfaces of the board, and conducts the inspection by configuring the power supply conductor and other conductors into a circuit.

Therefore, the terminal on one side of the board is connected to the terminal of the power supply conductor via a resistor. Then, the terminals of the power supply conductor and other conductors on the other side of the board are probed to read the resistance value, and the resistance value is used to check for disconnections and short circuits.

[Effect]

According to the above method, only one side of the ceramic substrate is inspected by blowing. Then, the resistance value of the circuit between the two conductors increases to infinity, thereby detecting a break, and the short-circuit occurs midway, reducing the resistance value, thereby detecting a short circuit.

〔Example〕

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

In FIG. 1, numeral 1 is a ceramic substrate, 2a to 2d are insulating layers, 3a to 3c are power supply conductors, 3d, 3e
2 is a conductor for output signals, and 4a to 4g and 5a to 5d are terminals, which are constructed in the same manner as in FIG.

Therefore, the terminals 5a to 5d on the back surface 1b of the substrate 1 are connected by a circuit 9 having a resistor 8. Then, in this state, on the surface 1a of the substrate 1, for example, the terminals 4a and 4
The resistance value is read by the tester 10 by contacting the probe 6.7 with the probe 6.7.

As a result, the power supply conductor 3b and the other conductor 3d are connected to the inspection machine 10 via the circuit 9 having the resistor 8, and both door bodies 3
b and 3d are inspected simultaneously. And conductors 3b, 3d
If there is a break in the middle of the wire, the resistance value will become infinite and this can be detected. In addition, the conductor 3d and the power supply conductor 3a or 3b
If a short circuit occurs at the intersection P1 or P2, resistor 8
are connected in parallel, their value becomes smaller, and this allows you to check for shorts with the power supply.

Thereafter, by changing the contact position of the probe 6.7 in the same manner, each conductor of the wiring net is inspected for disconnection or short circuit.

〔Effect of the invention〕

As described above, according to the present invention, even in the case of a highly multilayered ceramic substrate without through-holes, it is possible to inspect by blowing one side of the substrate, simplifying the inspection mechanism and shortening the inspection time. .

Since the power supply conductor can be used to simultaneously test for short circuits as well as disconnections, test performance is improved.

The structure is simple because only a circuit having a resistance is connected.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the inspection method of the present invention, and FIG. 2 is a diagram showing a conventional inspection state. In the figure, 1 is a ceramic substrate, 1a is a front surface, lb is a back surface, 4a, 4c, 5a, 5b are terminals, and 8 is a resistor.

Claims (1)

[Claims] A power supply and other conductor terminals (5a, 5b) on one side (1b) of the ceramic substrate (1) are connected in a circuit via a resistor (8), A method for inspecting a wiring net for a ceramic substrate, which comprises probing the power source and other conductor terminals (4a, 4c) on the other surface (1a) to inspect for disconnections and short circuits based on resistance values.