JPH11133090A - Substrate inspection device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inspect a substrate having a pad part with fine pitch at both ends. SOLUTION: A computer 44 turns ON switch SW11 an switch SW21. By this, the output voltage Vx from an amplifier 81 is detected and held at the maximum value by a peak hold circuit 76. If a printed pattern 34c is cut in the first section, the output voltage Vx from the amplifier 8 concerning the printed pattern 34c becomes very small value. By this, whether cable is cut or not can be easily judged. Also, by making switch SW11a and switch SW23 ON, the conduction state in the section from the lower part of a lower electrode 64a and to a pad 36c can be judged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a substrate inspection apparatus, and more particularly to an inspection of wiring using capacitance.

[0002]

2. Description of the Related Art In general, a method for inspecting a printed circuit board is such that a probe is brought into contact with both ends of a wiring to be inspected, a test signal is supplied from one probe, and conduction is determined based on whether or not this can be detected from the other probe. Make a decision.

[0003] However, today, the fine pitch of wiring has been advanced, and in the inspection method of bringing the probe into contact,
There were the following problems. First, the probe must be supplemented in accordance with the refinement of the end portion, and the insufficient strength of the probe at the time of pressing becomes a serious problem. In addition, precision of positioning is also required to be precise. In addition, the edges are scratched to contact the edges. Especially,
Since the pad portion of the fine pitch is small, the adverse effect due to the scratch becomes large.

[0004] The present invention solves the above problems,
An object of the present invention is to provide a printed circuit board inspection apparatus and a method thereof that can easily perform an inspection without damaging a wiring to be inspected.

[0005]

According to a first aspect of the present invention, there is provided a board inspection apparatus for inspecting a board to be inspected having one end arrangement region in which one end of an adjacent inspection target wiring is arranged at high density. A first signal detection terminal that is non-contact-coupled with each end of the one-end arrangement region, and a first inspection target wiring that is not in contact with a wiring portion excluding one end and the other end thereof A test signal supply terminal to be coupled, test signal supply means for supplying a test signal from the test signal supply terminal to the first inspection target wiring, and a detection signal detected from the first signal detection terminal. Determining means for determining the continuity of the first wiring to be inspected based on the determination.

In the substrate inspection apparatus according to the second aspect, the test signal supply terminal is at least a first test signal supply terminal and a second test signal terminal located apart from the first test signal supply terminal. It is characterized by having a signal supply terminal.

According to a third aspect of the present invention, the substrate to be inspected further has another end arrangement region where the other end of the first wiring to be inspected is arranged at a high density. A second signal detection terminal is provided which is non-contact-coupled to each end of the end arrangement region.

According to a fourth aspect of the present invention, there is provided a substrate inspection apparatus for inspecting a substrate to be inspected having one end arrangement region where one end of an adjacent wiring to be inspected is arranged at high density. A test signal is supplied to the first wiring to be inspected from the test signal supply terminal and the test signal supply terminal which are non-contact-coupled to the wiring part excluding one end and the other end of the wiring to be inspected. Test signal supply means, a second inspection target wiring, a short-circuit inspection terminal non-contact-coupled to a wiring portion excluding one end and the other end thereof, and a detection signal detected by the short-circuit inspection terminal. Determining means for determining a short circuit between the first and second wirings to be inspected based on the determination.

A board inspection apparatus according to claim 5, wherein the inspection is performed on a board to be inspected having one end arrangement region in which one end of an adjacent wiring to be inspected is arranged at a high density. A first signal detection terminal that is non-contact-coupled to each end of the unit arrangement region, and a test signal supply that is non-contact-coupled to a wiring portion excluding one end and the other end of the first inspection target wiring Test signal supply means for supplying a test signal from the test signal supply terminal to the first test target wiring from the test signal supply terminal, and a wiring portion excluding one end and the other end of the second test target wiring. Based on a detection signal detected from the non-contact-coupled short-circuit inspection terminal and the first signal detection terminal, the continuity of the first inspection target wiring is determined or detected by the short-circuit inspection terminal. Based on detection signal , Characterized by comprising determination means for performing short-circuit determination between the first and second inspection target wiring.

[0010] In the substrate inspection apparatus according to the sixth aspect, the test signal supply terminal may include at least a first test signal supply terminal and a second test signal located at a distance from the first test signal supply terminal. It is characterized by having a signal supply terminal.

According to a seventh aspect of the present invention, the substrate to be inspected further has another end arrangement region in which the other end of the first wiring to be inspected is arranged at high density. A second signal detection terminal is provided which is non-contact-coupled to each end of the end arrangement region.

In a preferred embodiment of the present invention, a test signal from the test signal supply means can be supplied to the short detection terminal.

In a ninth aspect of the present invention, the test signal is a signal having a sudden change.

According to a tenth aspect of the present invention, the test signal is a signal having an abrupt change, and the determining means determines that the first signal has a sharp change after the predetermined signal has an abrupt change. The conductive state of the wiring is determined based on the maximum value of the voltage detected at the signal detection terminal.

In the substrate inspection apparatus according to the eleventh aspect, the test signal is a signal having an abrupt change, and the determination means determines that the short-circuit inspection has been performed after the predetermined signal has an abrupt change. The short circuit state is determined based on the maximum value of the voltage detected at the terminal.

In the substrate inspection method according to the twelfth aspect, the substrate inspection method may include inspecting a substrate to be inspected having one end arrangement region in which one end of an adjacent inspection target wiring is arranged at a high density. The above-mentioned ends and the first signal detection terminal are non-contact-coupled to each other above the unit arrangement region, and the first inspection target wiring is excluding one end and the other end thereof, and a test signal supply terminal. Are connected in a non-contact manner, a test signal is supplied to the first wiring under test, and the conduction of the first wiring under test is determined based on a detection signal detected from the first signal detection terminal. It is characterized by the following.

According to a thirteenth aspect of the present invention, there is provided a board inspection method for inspecting a board to be inspected having one end arranged region where one end of an adjacent wiring to be inspected is arranged at high density. The test signal supply terminal is connected to the test signal supply terminal in a non-contact manner except for one end and the other end of the test target wiring, and a test signal is supplied from the test signal supply terminal to the first test target wiring. Then, with respect to the second wiring to be inspected, the wiring part excluding one end and the other end thereof and the short-circuit inspection terminal are non-contact-coupled, and based on the detection signal detected by the short-circuit inspection terminal, It is characterized in that a short circuit between the first and second wirings to be inspected is determined.

According to a fourteenth aspect of the present invention, there is provided a board inspection jig for inspecting a board to be inspected having one end arrangement region where one end of an adjacent wiring to be inspected is arranged at high density. A test signal supply terminal for supplying a test signal to the first wiring to be tested, wherein the first wiring to be tested is non-contact-coupled to a wiring portion excluding one end and the other end of the first wiring to be tested. Test signal supply terminal,
And a first signal detection terminal for detecting a signal from the first signal detection terminal, the first signal detection terminal being non-contact-coupled to each end of the one end arrangement region. It is characterized by having.

According to a fifteenth aspect of the present invention, there is provided a board inspection jig for inspecting a board to be inspected having one end arrangement region where one end of an adjacent wiring to be inspected is arranged at high density. A test signal supply terminal for supplying a test signal to the first inspection target wiring, wherein the test signal is non-contact-coupled to a wiring part excluding one end and the other end of the first inspection target wiring. A supply terminal, and a short-circuit inspection terminal for detecting a detection signal for performing a short-circuit determination between the first and second inspection target wirings, wherein one end and the other end of the second inspection target wiring And a short-circuit inspection terminal that is non-contact-coupled to the wiring part except for the above.

In the present invention, the term "substrate" refers to a substrate on which a wiring can be formed or a substrate on which a wiring is actually formed, regardless of the material, structure, shape, dimensions, and the like. For example,
Glass epoxy board, film board, etc., CPU
And the like for mounting circuit elements such as. Further, it includes a composite substrate in which a socket or the like is mounted on a glass epoxy substrate or the like, and a substrate in which circuit elements are mounted.

The term "wiring" refers to a conductor for the purpose of conducting, regardless of the material, structure, shape, size and the like. In addition to printed patterns, through holes, pins, etc. formed on the board,
This is a concept including a conductive portion of an electric cord, socket, connector, pin, or the like attached to a substrate.

The terms "one end of the wiring" and "the other end of the wiring" refer to a portion of the wiring that serves as an input point or an output point of a signal for inspection, irrespective of the material, structure, shape, size, and the like. Inspection end of printed pattern, connector connection end, connection pin, pad for connecting bonding wire, etc., pad for connecting circuit element or socket, insertion part provided in socket mounted on board And the part which becomes an electrical connection point with other parts such as the input / output end of the connector.

"Non-contact coupling" refers to coupling two or more members so that signals can be transmitted and received in an insulated state. In the embodiment, the electrostatic coupling coupled using capacitance is used. Applicable. However, it is not limited to the embodiment.

"Signal" refers to a signal used for inspection, and is a concept including both voltage and current. In addition to an AC signal such as a sine wave, a DC signal, a rectangular signal, a triangular signal, a pulse signal, and the like are also included.

"Based on the detection signal detected from the signal detection terminal" means the voltage itself of the detection signal or a physical quantity corresponding to or related to the voltage. Therefore, in addition to the voltage, for example, a current corresponding to or related to the voltage, an integrated value, a differential value, and the like are also included.

The term "detection of the continuity of the wiring" is a concept including detection of a resistance value of the wiring such as detection of a disconnection or short-circuit of the wiring, detection of a half-disconnection, and the like.

The term "signal having a rapid change" means a signal having a large amount of change per unit time such as a voltage or a current. For example, a DC signal having a step-like rising or falling, a triangular signal, a rectangular signal, or the like. Shape signals, pulse signals, and the like are included.

[0028]

According to the first aspect of the present invention, each of the ends and the first signal detection terminal are non-contact-coupled to each other above the one end arrangement area. Connecting the test signal supply terminal to the first test target wiring in a non-contact manner, excluding one end and the other end thereof, and supplying a test signal to the first test target wiring; Is determined based on a detection signal detected from the signal detection terminal. Therefore, a test signal can be supplied to the wiring to be inspected even if each end of the one end arrangement region is arranged at high density. Thereby, a continuity test from the lower portion of the first signal detection terminal to the one end can be performed. Further, since the continuity determination can be performed without contact with the terminal on the one end side, the terminal on the one end side is not scratched.

[0029] In the substrate inspection apparatus according to the second aspect, the test signal supply terminal may include at least a first test signal supply terminal and a second test signal terminal located apart from the first test signal supply terminal. It has a signal supply terminal. This first
By supplying a test signal from the test signal supply terminal and the second test signal supply terminal, it is assumed that the test signal is supplied to the lower side of either the first test signal supply terminal or the second test signal supply terminal. A wiring continuity test can be performed.

According to a third aspect of the present invention, the substrate to be inspected further has another end arrangement region in which the other end of the first wiring to be inspected is arranged at a high density. A second signal detection terminal is provided which is non-contact-coupled to each end of the end arrangement region. Therefore, the continuity test between the test signal supply terminal and the other end can be performed without contact with the terminal on the other end.

A substrate inspection apparatus according to claim 4 or claim 13.
In the substrate inspection method of the first aspect, the wiring portion except for one end and the other end of the first wiring to be inspected is non-contact-coupled to the test signal supply terminal, and the first test target wiring is Supply the test signal to the wiring to be inspected
With respect to the second wiring to be inspected, the wiring part except the one end and the other end and the short-circuit inspection terminal are non-contact-coupled,
A short circuit between the first and second wirings to be inspected is determined based on a detection signal detected at the short inspection terminal. Therefore, a test signal can be supplied to the wiring to be inspected even if each end of the one end arrangement region is arranged at high density. This makes it possible to determine a short circuit between the first and second inspection target wirings.

According to a fifth aspect of the present invention, the first signal detection terminal is non-contact-coupled to each end of the one end arrangement region. The test signal supply terminal includes a first
Of the wiring to be inspected is non-contact-coupled to a wiring part excluding one end and the other end. The test signal supply unit supplies a test signal from the test signal supply terminal to the first inspection target wiring. The short-circuit inspection terminal,
The second inspection target wiring is non-contact-coupled to a wiring part excluding one end and the other end. The determination means is configured to determine the continuity of the first inspection target wiring based on a detection signal detected from the first signal detection terminal, or based on a detection signal detected at the short-circuit inspection terminal. Then, a determination of a short circuit between the first and second inspection target wirings is performed.

Therefore, a test signal can be supplied to the wiring to be inspected even if each end of the one end arrangement region is arranged at high density. This makes it possible to perform a continuity test from a lower portion of the first signal detection terminal to the one end or a short-circuit determination between the first and second test target wirings.

In the substrate inspection apparatus according to the sixth aspect, the test signal supply terminal may include at least a first test signal supply terminal and a second test signal terminal located apart from the first test signal supply terminal. It has a signal supply terminal. This first
By supplying a test signal from the test signal supply terminal and the second test signal supply terminal, it is assumed that the test signal is supplied to the lower side of either the first test signal supply terminal or the second test signal supply terminal. A wiring continuity test can be performed.

According to a seventh aspect of the present invention, in the substrate inspecting apparatus, the substrate to be inspected further has another end arranging area in which the other end of the first wiring to be inspected is arranged at a high density. A second signal detection terminal is provided which is non-contact-coupled to each end of the end arrangement region. Therefore, the continuity test between the test signal supply terminal and the other end can be performed without contact with the terminal on the other end.

In the substrate inspection apparatus of the eighth aspect, a test signal from the test signal supply means can be supplied to the short detection terminal. Therefore, the short detection terminal can be used as a terminal for supplying the test signal.

According to a ninth aspect of the present invention, the test signal is a signal having a sudden change. Therefore, the detection signal also changes abruptly in response to the change of the signal. For this reason, the conduction state of the wiring can be determined by detecting this rapid change.
Inspection can be performed at high speed. As a result, it is hardly affected by hum noise and the like.

According to a tenth aspect of the present invention, the test signal is a signal having an abrupt change, and the determining means determines that the first signal has a sharp change after the predetermined signal has an abrupt change. The conductive state of the wiring is determined based on the maximum value of the voltage detected at the signal detection terminal. The maximum occurs approximately at the same time as the signal undergoes a sudden change. Therefore, the conduction state of the wiring can be known in a very short time.

In the substrate inspection apparatus of the eleventh aspect, the test signal is a signal having an abrupt change, and the determination means determines that the short-circuit inspection has been performed after the predetermined signal has an abrupt change. The short-circuit state is determined based on the maximum value of the voltage detected at the terminal. The maximum occurs approximately at the same time as the signal undergoes a sudden change. Therefore, the short-circuit state of the wiring can be known in a very short time.

According to a fourteenth aspect of the present invention, there is provided a board inspection jig for inspecting a board to be inspected having one end arrangement region where one end of an adjacent wiring to be inspected is arranged at high density. A test signal supply terminal for supplying a test signal to the first wiring to be tested, wherein the first wiring to be tested is non-contact-coupled to a wiring portion excluding one end and the other end of the first wiring to be tested. Test signal supply terminal,
And a first signal detection terminal for detecting a signal from the first signal detection terminal, the first signal detection terminal being non-contact-coupled to each end of the one end arrangement region. ing. Therefore, a test signal can be supplied to the wiring to be inspected even if each end of the one end arrangement region is arranged at high density. Thus, a continuity test from the lower portion of the first signal detection terminal to the one end can be performed.

According to a fifteenth aspect of the present invention, there is provided a board inspection jig for inspecting a board to be inspected having one end arrangement region where one end of an adjacent wiring to be inspected is arranged at high density. A test signal supply terminal for supplying a test signal to the first inspection target wiring, wherein the test signal is non-contact-coupled to a wiring part excluding one end and the other end of the first inspection target wiring. A supply terminal, and a short-circuit inspection terminal for detecting a detection signal for performing a short-circuit determination between the first and second inspection target wirings, wherein one end and the other end of the second inspection target wiring And a short-circuit inspection terminal that is non-contact-coupled to the wiring part except for the above. Therefore, a test signal can be supplied to the wiring to be inspected even if each end of the one end arrangement region is arranged at high density. This makes it possible to determine a short circuit between the first and second inspection target wirings.

[0042]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a functional configuration of a bare board tester 1 which is a board inspection apparatus using capacitance. The bare board tester 1 conducts / conducts printed patterns on a printed circuit board (bare board) before circuit elements are mounted.
This is a device for inspecting non-conduction and the like. In particular, it is suitable for inspection of a substrate having a fine pad in which one end of an adjacent inspection target wiring is arranged at high density.

The bare board tester 1 has a signal processing section 7, switch sections SW1 and SW2, and a sensor module 50 as a board inspection jig. The signal processing unit 7 includes a signal source 46 as a test signal supply unit, a signal detection unit 48, and a computer 44 as a determination unit.

First, the substrate to be inspected is shown in FIG.
This will be described with reference to FIG. The substrate 32 has a plurality of printed patterns 34c, 34d,.
Are formed. These plural print patterns 34
, 34d,...
Call it 4. One end of each of the print patterns 34c, 34d,... Has a pad 36c, 36d,. The pads 36c, 36d,... Are collectively referred to as a pad section 36. The arrangement pitch of the pads 36c, 36d,... Is extremely small (fine pitch (high density)).

The print patterns 34c, 34d,
The other ends of the pads 38c, 38d,.
・ It has become. The pads 38c, 38d,... Are collectively referred to as a pad section 38. Each pad 38c, 38d,
Are extremely small (fine pitch).

In this embodiment, the pad portion 36 corresponds to the one end portion arrangement region, and the pad portion 38 corresponds to the other end portion arrangement region.

The sensor module 50 shown in FIG. 1 is arranged on the wiring to be inspected on the substrate 32. The sensor module 50 will be described with reference to FIG. FIG. 3A
3B is a plan view, FIG. 3B is a sectional view taken along line XX of FIG. 3A, and FIG. 3C is a bottom view. As shown in FIGS. 3B and 3C, a lower electrode 6 serving as a first test signal supply terminal is provided on the lower surface of the substrate 60.
3a, lower electrode 63 serving as a second test signal supply terminal
b, a lower electrode 62a serving as a first signal detection terminal, and a lower electrode 62b serving as a second signal detection terminal are provided. The lower electrodes 63a, 63b, 62a, 62b are covered with an insulating film 70. The lower electrode 62a is connected to each of the pads 38a to 38e of the pad portion 38 of the substrate 32 to be inspected.
(See FIG. 2). Therefore, a capacitor (capacitance) is formed by the lower electrode 62 a of the sensor module 50, the insulating film 70, and each pad of the pad section 38. Similarly, for each of the other lower electrodes 62b, the pads 36a to 36e of the pad portion 36 are formed.
2 (see FIG. 2), and the lower electrode 62
a, the insulating film 70, and each pad of the pad section 36 form a capacitor.

Further, the lower electrode 63a is arranged so as to be located above the pattern 34d (see FIG. 2) which is the second wiring to be inspected. Therefore, a capacitor is formed by the lower electrode 63a, the insulating film 70, and the pattern 34d. The lower electrode 63b is arranged so as to be separated from the lower electrode 63a and to be located above the pattern 34d. Lower electrode 63b, insulating film 70, and pattern 34
d forms a capacitor.

The lower electrode 64a is arranged so as to be located above the pattern 34c which is the first wiring to be inspected. Therefore, a capacitor is formed by the lower electrode 64a, the insulating film 70, and the pattern 34c. The lower electrode 64b is separated from the lower electrode 64a by a pattern 34c.
It is arranged so that it may be located above. Lower electrode 64
b, the insulating film 70, and the pattern 34c form a capacitor.

In this embodiment, the lower electrode 6
As described later, 3b and 64b are power supply electrodes and also function as detection electrodes.

As shown in FIGS. 3A and 3B, the upper electrodes 72a and 7
2b, 73a, 73b, 74a, and 74b are provided. The upper electrodes 72a, 72b, 73a, 73b are shown in FIG.
B, the lower electrodes 62a, 62b,
63a and 63b are connected by through holes. Similarly, the upper electrodes 74a and 74b are also electrically connected to the lower electrodes 64a and 64b by through holes (not shown).

In this embodiment, the upper electrodes 72a,
72b, 73a, 73b, 74a, 74b are connected to lower electrodes 62a, 62b, 63a, 63b, 64, respectively.
a, 64b. However, the present invention is not limited to this, and the upper electrodes 72a, 72b, 73a, 73b, 74
Regarding the shape of the lower electrodes 62a and 74b,
a, 62b, 63a, 63b, 64a, 64b as long as they can be electrically connected.

The switch section SW1 shown in FIG. 1 is composed of a plurality of switches, and outputs a test signal from the signal source 46 to the upper electrode 73a connected to the lower electrode 63a and the upper electrode 73b connected to the lower electrode 63b. , Lower electrode 64
upper electrode 74a and lower electrode 64b connected to a
To the upper electrode 74b connected to the upper electrode 74b. Switch SW
2 also includes a plurality of switches, and the lower electrode 62
upper electrode 72a or lower electrode 62b connected to a
The detection signal detected by the upper electrode 72b connected to the signal detection unit 48 is supplied to the signal detection unit 48. The connection status of the switch unit SW1 and the switch unit SW2 is switched by a connection command from the computer 44.

Since the lower electrodes 63b and 64b are both power supply electrodes and function as detection electrodes, as will be described later, the switch section SW1 and the switch section S
It is connected to any of W2.

The signal detecting section 48 performs a predetermined process on the applied detection signal and supplies the same to the computer 44. The computer 44 determines the conduction or short-circuit state of the selected print pattern based on the detection signal provided from the signal detection unit 48.

Next, power supply to each electrode and signal detection will be described with reference to FIG. Here, a case will be described as an example in which a continuity test of the pattern 34c and a short-circuit test between the pattern 34c and the pattern 34d shown in FIG. 2 are performed.

First, the continuity test of the pattern 34c will be described. In the following, a test signal is supplied from the lower electrode 64a, and a section (hereinafter referred to as a first section) from a portion below the lower electrode 64a to the head 38c and the lower electrode 64a
In the following, a description will be given of a case in which conduction is inspected in a section (hereinafter, referred to as a second section) from the lower portion to the hat 36c.

The lower electrode 64a is provided above the pattern 34c.
However, a lower electrode 62a is disposed above the pad portion 38 at one end of the pattern 34c, and a lower electrode 62b is disposed above the pad portion 36 at the other end. Since the lower electrodes 64a, 62a and 62b are connected to the switches SW1 and SW2, respectively, as shown in FIG.
The equivalent circuit shown in FIG. In this case, the resistance R1 represents the internal resistance of the switch SW11a. The resistance R3 represents the resistance in the first section of the print pattern 34c. The resistance R5 is the print pattern 3
4c represents the resistance in the second section. Resistance R13, R15
Represents a ground resistance in the signal detection unit 48. Capacitance C1
Are the lower electrode 64a, the insulating film 70, and the pattern 34c.
And the capacitor formed by Capacitance C3
Represents a capacitor formed by the lower electrode 62a, the insulating film 70, and the pad 38c. Capacitance C5
Represents a capacitor formed by the lower electrode 62b, the insulating film 70, and the pad 36c. E is the signal source 4
6 represents the DC voltage.

With reference to FIG. 6, a description will be given of the switching timing of the switches during the signal processing. In FIG. 6, for convenience of description, descriptions of some of the switches constituting the switch units SW1 and SW2 are omitted.

In this embodiment, a constant voltage source is used as the signal source 46 as shown in FIG. Therefore,
The switch section SW1 shown in FIG. (See FIG. 6, (a)). The computer 44 sends an instruction to the switch section SW2 to turn on the switch SW21 (see FIG. 6, (c)). And
The computer 44 sends an instruction to the switch unit SW1, and
The switch SW11a is turned on (ON) (FIGS. 5 and 6).
(B)).

When the above-described switch SW11a is turned on (see FIGS. 6 and 6C), the equivalent circuit shown in FIG. 5 is closed, and the following current i flows: i = E / (R1 + R2 + R3 ) · Exp (−αt) (1) where α = 1 / [(R1 + R2 + R3) · 1 / {(1 / C1) + (1 / C3)}].

Therefore, the output voltage V from the amplifier 81
x is represented by the following equation (3).

Vx = R3 · i (3) From the equations (1) and (3), the output voltage Vx from the amplifier 81 is expressed by the following equation (4).

Vx = R3 / E / (R1 + R2 + R3) · exp (−αt) (4) where α = 1 / [(R1 + R2 + R3) · 1 / {(1 / C1) + (1 / C3)}].

After the voltage Vx is amplified by the amplifier 81, its maximum value (a value corresponding to the voltage Va in FIG. 6D) is detected and held by the peak hold circuit 76. The peak hold circuit 76 includes a D / A converter (not shown), and the digitized maximum value is sent to the computer 44. Note that a part of the function of the peak hold circuit 76 can be realized by using the computer 44.

The computer 44 determines the conduction state of the first section of the print pattern 34c based on the maximum value. As can be seen from equation (4), the output voltage Vx from the amplifier 81 substantially indicates the maximum voltage Va (= R3 / (R1 + R2 + R3) E) at the same time when the switch SW11a is turned ON (FIG. 6, (d)).

If the print pattern 34c is the first
If there is no disconnection in the section, the output voltage Vx from the amplifier 81 becomes as shown in (d). On the other hand, if the print pattern 34c is disconnected in the first section, the output voltage Vx from the amplifier 81 for the print pattern 34c is as shown in (h), and the maximum value V'a is an extremely small value. . This can be understood from the fact that, in the equation (2), when R2 representing the resistance of the print pattern is set to infinity (complete disconnection), Vx = 0 irrespective of the time t.

Therefore, for example, whether or not the wire is broken can be easily determined based on whether or not the maximum value is between a preset lower limit reference value and a preset upper limit reference value. Thus, the maximum value detection processing by the peak hold circuit 76 can be completed in a very short time.
Therefore, the process of determining the conduction state of the print pattern is
This can be performed in a very short time. As a result, it is hardly affected by hum noise and the like.

Next, the computer 44 operates the switch S
W21 and the switch SW11a are turned off (FIG. 6, (e)), and the discharge switch SW31 is turned on. Thus, the capacitors C1 and C3 are discharged.

Next, the computer 44 turns off the discharge switch SW31, sends a connection command to the switch section SW2, and turns on the switch SW23 (see FIG. 6, (f)). As a result, the second section of the pattern 34c is closed, and the switch SW11a is substantially turned on as in the case described above (see (e) of FIG. 6), and the output voltage Vx from the amplifier 83 becomes the maximum value. (See FIG. 6, (f)). The computer 44 determines the print pattern 34 based on the maximum value in the same manner as described above.
The conduction state in the second section of c is determined.

Then, similarly, the switch SW23 and the switch SW11a are turned off and the discharge switch S
W31 is turned on. Thereby, the capacitors C1, C
5 is discharged.

Next, the computer 44 turns off the discharge switch SW31, sends a command to the switch SW2, turns off the switch SW23, and then sends a command to the switch SW1 to turn off the switch SW11a. The switch SW11b is turned ON (see FIG. 6, (i)). And then, the switch SW
21 is turned ON. As a result, the section of the pattern 34c (hereinafter referred to as the third section) from the lower portion of the lower electrode 64b to the hat 38c is closed, and the switch SW11b is substantially turned on at the same time as in the above-described case (see FIG. 6, (J)), the output voltage Vx from the amplifier 81
Indicates the maximum value Vc (see FIG. 6, (k)). The computer 44 determines the conduction state of the third section of the print pattern 34c based on the maximum value Vc, as in the case described above.

As described above, the conduction state of the third section including the lower region of the lower electrode 64a is determined so that, as shown in FIG. , Which can be detected.

As described above, the test signal is applied from any part except the both ends of the printed pattern 34c by using the electrostatic coupling, and the test signal is taken out from the common electrode at both ends, so that the fine pitch is provided at both ends. A continuity test of the substrate on which the pads are formed can be performed.

Further, 2 above the print pattern 34c
By providing the power supply electrodes at the locations, a more reliable conduction test can be performed.

The continuity test can be performed on the print pattern 34d in the same manner.

Next, a description will be given of an inspection for a short circuit between patterns. Here, a case where a short-circuit inspection between the pattern 34c and the pattern 34d is performed will be described as an example. In the short-circuit inspection, power is supplied from the lower electrode 64a for power supply or the lower electrode 64b on the pattern 34c without using the electrodes above the pad portions 36 and 38 at both ends, and the signal is supplied from the lower electrode 63b on the pattern 34d. It may be determined whether or not is detected. In this case, the lower electrode 63b becomes a short-circuit inspection terminal. Specifically, the switch SW11a is turned on and the switch SW24 is turned on to determine what kind of signal is detected. The test signal may be supplied by turning on the switch SW11b.

Power may be supplied from the lower electrode 63a or 63b for power supply on the pattern 34d, and it may be determined whether or not a signal is detected by the lower electrode 64b on the pattern 34c. In this case, the lower electrode 64b becomes a short-circuit inspection terminal.

As described above, with respect to a short circuit between adjacent print patterns, without using a lower electrode commonly provided above the both ends, the electrostatic discharge from any part except the both ends of one of the print patterns can be performed. By providing a test signal using coupling, and detecting the test signal using electrostatic coupling from any portion except the both ends of the other print pattern, fine pitch pads were formed at both ends. The board can be inspected for short circuits between adjacent printed patterns.

Thus, it is not necessary to use an expensive fine-pitch probe even on a substrate on which one end or the other end of the wiring is arranged at high density. Further, the other end of the wiring is not damaged.

Further, the predetermined signal is a signal having a sudden change. Therefore, when the signal is given, the voltage generated at the first signal detection terminal also changes abruptly according to the change of the signal. For this reason, the conduction state of the wiring can be determined by detecting this rapid change, so that the inspection can be performed at high speed. As a result, it is hardly affected by hum noise and the like.

That is, even a high-density wiring board can be inspected inexpensively and with high reliability in a short time.

In this embodiment, the lower electrode 6
Reference numerals 3b and 64b also serve as test signal supply electrodes and detection electrodes. However, they may be provided separately.

2. Other Embodiments Note that the switch SW11 immediately after the peak value detection process (the process of detecting the maximum value corresponding to the voltage Va) of the print pattern 34c by the peak hold circuit 76 is completed.
a may be turned off and the switch SW12a may be turned on. With this configuration, it is possible to shift to the inspection of the next print pattern 34d without waiting for the current i flowing through the print pattern 34c to become substantially zero. Therefore, the conduction state of the print pattern can be inspected in a shorter cycle. Further, with this configuration, even if the above-described time constant (the reciprocal of α in Equations (1) and (2)) is large, the inspection cycle does not become extremely large.

Further, in the above-described embodiment, a signal having a rapid change has been described as an example of the predetermined signal used for inspection, but the present invention is not limited to this. As the predetermined signal used for the inspection, for example, an AC signal such as a sine wave AC may be used.

When an AC signal is used as the predetermined signal, for example, a sine wave oscillator may be used as the signal source 46 as shown in FIG. For example, a sine wave having a frequency of about 10 kHz is generated in the signal source 46. Also, as an element constituting the signal detection unit 48, FIG.
Waveform observation circuit 88 instead of the peak hold circuit 76
May be used. The waveform observation circuit 88 is a circuit that processes an input signal and evaluates its level and waveform. Specifically, for example, a detection circuit or an oscilloscope is used.

In this case, as shown in FIG. 9, the computer 44 switches the switches of the switch unit SW1 and the switch unit SW2 (see FIG. 9, (b)) to thereby generate the sine wave generated by the signal source 46. (FIG. 9,
(See (a)) is applied to the print pattern to be inspected, and the conduction state of each print pattern is determined based on the data obtained via the signal detection unit 48.

If the print pattern is not broken, the output voltage Vx from the amplifier 81 is as shown in FIG. On the other hand, if the print pattern is broken,
The output voltage Vx from the amplifier 81 is as shown in FIG.
That is, when the print pattern is broken, the output level becomes an extremely small value, so that the determination can be made easily.

When such an AC signal is used,
The speeding up of the inspection as in the above-described embodiment using a signal having a sudden change cannot be expected so much. However, by using such an AC signal, the device can be configured using a circuit relatively frequently used for a non-contact inspection device such as a sine wave oscillator and a detection circuit, so that the design cost of the device can be reduced. In addition, it is expected that the production cost of the apparatus can be reduced and the delivery time can be shortened by diverting existing parts.

In the above-described embodiment, a constant voltage source is used as the signal source 46 (see FIG. 6A), and a DC voltage generated from the signal source 46 is connected to each switch of the switch unit. By cutting off (see FIG. 6, (c)), a step-like voltage having a steep rising portion is obtained. However, as the signal source 46, a circuit or the like that sequentially generates a signal having a steep change is used. Can also be used.

FIG. 10 is a timing chart of signal processing signals when the above-described signal source 46 is used. In this example, a rectangular wave generating circuit is used as the signal source 46. The computer 44 switches the switches of the switch units SW1 and SW2 substantially in synchronization with the phase of the rising portion (see FIG. 11, (a)) of each rectangular signal generated by the signal source 46 (FIG. 11, (B),
(See FIG. 1C), and the rectangular signals sequentially generated by the signal source 46 can be distributed to the print patterns 34c, 34d,... (See FIG. 1). The state of the output voltage Vx from the amplifier and the processing after output from the amplifier in this example are the same as those in the example shown in FIG.

In the example shown in FIG. 11, the signal source 46 is configured to generate a rectangular wave. However, as shown in FIG. 12A, the signal source 46 may be configured to generate a triangular wave. In FIG. 12A, each triangular signal has a sharp rising portion (a). FIG. 12B
The signal source 46 may be configured to generate a pulse train as shown in FIG. As in FIG. 12A, also in FIG. 12B, each pulse signal has a sharp rising portion (b).

The signal having a sharply rising portion is not limited to these, and includes a signal that rises at a short time in addition to a signal that rises at time 0. Also, a signal having a sharp falling portion is included.

In the present embodiment, a substrate in which pad portions having fine pitches at both ends are formed on one surface has been described as an example, but one end portion is provided on the front surface (first surface) and the back surface (first surface). Also for a substrate having a pad at the other end on the (second surface opposite to the surface), the sensor module 50 can be provided on both surfaces and connected to the signal processing unit to perform the same test.

In the above embodiment, the continuity of the wiring is determined based on the maximum voltage generated at the first signal detection terminal after the signal has changed abruptly. The present invention is not limited to this. For example, the average value of the voltage generated at the first signal detection terminal within a predetermined time after a sudden change in the signal, the voltage value after the predetermined time has elapsed, the steady-state deviation voltage, the first
When a signal having a sudden change, such as a maximum value, an average value, or an integrated value of a current flowing through the signal detection terminal, is provided, the wiring is performed based on the amount related to the voltage generated at the first signal detection terminal Can be configured to determine the conduction state of the switch. However, if the continuity of the wiring is determined based on the maximum voltage as in the embodiment, the continuity of the wiring can be inspected in a shorter time.

Note that some or all of the functions of the computer 44 shown in FIG. 1 can be realized by hardware logic. In addition, some or all of the functions of the signal source 46 or the signal detection unit 48 can be realized using a computer.

In the above embodiment, the second signal detection terminal is configured to be coupled to the other end of the wiring by capacitance. Thus, highly reliable inspection can be performed with a simple configuration.

Further, in the above-described embodiment, the case where the substrate to be inspected is a substrate having a wiring having a plurality of other ends connected to each other has been described as an example. The present invention is not limited to the inspection of a simple substrate.

Further, in the above embodiment, the bare board tester has been described as an example, but the present invention is not limited to the bare board tester. The present invention can be applied to a general board inspection apparatus and a general board inspection method, such as a board inspection apparatus on which a circuit element such as a CPU is mounted, a package inspection apparatus for mounting a circuit element, and the like.

A signal source for generating a DC signal is provided,
By sequentially switching the first switch means, a signal having the sudden change is obtained from the DC signal generated by the signal source, and the conduction of the wiring specified by the selected first signal detection terminal is performed. The state may be sequentially detected using the obtained signal.

In the above embodiment, the case where a dedicated jig is manufactured has been described. However, the present invention can be similarly applied to a universal type inspection apparatus.

[Brief description of the drawings]

FIG. 1 is an overall schematic diagram of a bare board tester 1 according to an embodiment of the present invention.

FIG. 2 is a plan view (part) of a substrate to be inspected.

FIG. 3A is a plan view of the sensor module 50. FIG. FIG. 3B is a sectional view taken along line XX of FIG. 4A. FIG. 3C
Is a perspective view of the lower surface of the sensor module 50 as viewed from above.

FIG. 4 shows a circuit configuration for explaining signal processing.

FIG. 5 is an equivalent circuit diagram for explaining signal processing.

FIG. 6 is a timing chart at the time of signal processing.

FIG. 7 is a diagram illustrating a case where a wire is disconnected below a lower electrode 64a.

FIG. 8 shows an equivalent circuit when a sine wave AC measurement circuit is used.

FIG. 9 is a timing chart when a sine wave AC measurement circuit is used.

FIG. 10 is a timing chart at the time of signal processing according to another example.

FIG. 11 is a diagram showing another embodiment of a signal shape.

[Explanation of symbols]

 32 ... board 44 ... computer 46 ... signal source 76 ... ··· Peak hold circuit E ··· Constant voltage SW1 ······ Switch part SW2 ······ Switch part Vx ··· ........... Output voltage

Claims (15)

[Claims] 1. A board inspection apparatus for inspecting a substrate to be inspected having one end arrangement region in which one end of an adjacent inspection target wiring is arranged at high density, wherein each end of said one end arrangement region is A first signal detection terminal that is non-contact-coupled; a test signal supply terminal that is non-contact-coupled with a wiring portion excluding one end and the other end of the first inspection target wiring; A test signal supply unit for supplying a test signal from the terminal to the first inspection target wiring; determining a conduction of the first inspection target wiring based on a detection signal detected from the first signal detection terminal; A board inspection apparatus comprising: a determination unit that performs the determination. 2. The substrate inspection apparatus according to claim 1, wherein the test signal supply terminal is at least a first test signal supply terminal and a second test signal supply terminal located apart from the first test signal supply terminal. A board inspection apparatus, comprising: a test signal supply terminal. 3. The substrate inspection apparatus according to claim 1, wherein the substrate to be inspected further has another end arrangement area in which the other end of the first wiring to be inspected is arranged at high density. A second signal detection terminal that is non-contact-coupled to each end of the other end arrangement region. 4. A substrate inspection apparatus for inspecting a substrate to be inspected having one end arrangement region in which one end of an adjacent inspection object wiring is arranged at a high density, wherein one end of the first inspection object wiring is provided. A test signal supply terminal that is non-contact-coupled to a wiring portion excluding the portion and the other end, a test signal supply unit that supplies a test signal from the test signal supply terminal to the first inspection target wiring, The inspection target wiring is connected to a wiring portion excluding one end and the other end thereof in a non-contact manner with a short-circuit inspection terminal, based on a detection signal detected by the short-circuit inspection terminal. 2. A board inspection apparatus, comprising: a determination unit configured to determine a short circuit between inspection target wirings. 5. A board inspection apparatus for inspecting a substrate to be inspected having one end arrangement region in which one end of an adjacent inspection target wiring is arranged at high density, wherein each end of said one end arrangement region is A first signal detection terminal that is non-contact-coupled; a test signal supply terminal that is non-contact-coupled with a wiring portion excluding one end and the other end of the first inspection target wiring; A test signal supply means for supplying a test signal from the terminal to the first wiring to be inspected; a short-circuit inspection for the second wiring to be inspected which is non-contact-coupled to a wiring part excluding one end and the other end thereof Terminal, based on the detection signal detected from the first signal detection terminal, based on the conduction determination of the first inspection target wiring, or based on the detection signal detected at the short-circuit inspection terminal,
Determining means for determining a short circuit between the first and second wirings to be inspected. 6. The board inspection apparatus according to claim 5, wherein the test signal supply terminal is at least a first test signal supply terminal and a second test signal supply terminal located apart from the first test signal supply terminal. A board inspection apparatus, comprising: a test signal supply terminal. 7. The substrate inspection apparatus according to claim 5, wherein the substrate to be inspected further has another end arrangement region in which the other end of the first wiring to be inspected is arranged at a high density. A second signal detection terminal that is non-contact-coupled to each end of the other end arrangement region. 8. The board inspection apparatus according to claim 5, wherein a test signal from the test signal supply means can be supplied to the short detection terminal. 9. The board inspection apparatus according to claim 1, wherein the test signal is a signal having a rapid change. 10. The substrate inspection apparatus according to claim 1, wherein the test signal is a signal having a sudden change, and the determination means is configured to determine whether or not the predetermined signal has a sudden change. And determining a conduction state of the wiring based on a maximum value of a voltage detected by the first signal detection terminal. 11. The board inspection apparatus according to claim 4, wherein the test signal is a signal having a sudden change, and the determination unit is configured to determine whether the predetermined signal has a sudden change. And determining the short-circuit state based on a maximum value of a voltage detected at the short-circuit inspection terminal. 12. A board inspection method for inspecting a substrate to be inspected having one end arrangement region in which one end of an adjacent inspection target wiring is arranged at a high density, wherein The end and the first signal detection terminal are non-contact-coupled to each other, and the first signal line to be inspected is non-contact-coupled to the test signal supply terminal except for one end and the other end thereof. Supplying a test signal to the first wiring to be inspected, and performing a continuity determination of the first wiring to be inspected based on a detection signal detected from the first signal detection terminal; Method. 13. A board inspection method for inspecting a board to be inspected having one end arrangement region where one end of an adjacent inspection object wiring is arranged at high density, wherein one end of the first inspection object wiring is provided. A test signal supply terminal and a wiring portion excluding the portion and the other end are non-contact-coupled to each other, a test signal is supplied from the test signal supply terminal to the first inspection target wiring, and a second inspection target wiring is provided. A non-contact coupling between a wiring portion excluding one end and the other end thereof and a short-circuit inspection terminal, and based on a detection signal detected by the short-circuit inspection terminal, the first and second inspection objects Determining a short circuit between the wirings; 14. A substrate inspection jig for inspecting a substrate to be inspected having one end arrangement region in which one end of an adjacent inspection object interconnection is arranged at a high density, wherein the first inspection object interconnection is provided. A test signal supply terminal for supplying a test signal to the first test target wiring, the test signal supply terminal non-contact coupling with a wiring portion excluding one end and the other end thereof, A first signal detection terminal for detecting a signal from the first signal detection terminal, the first signal detection terminal being non-contact-coupled to each end of the one end arrangement region; A board inspection jig provided with: 15. A board inspection jig for inspecting a substrate to be inspected having one end arrangement region where one end of an adjacent inspection object wiring is arranged at a high density, wherein a test is performed on the first inspection object wiring. A test signal supply terminal for supplying a signal, the test signal supply terminal being non-contact-coupled to a wiring part excluding one end and the other end of the first inspection target wiring; A short-circuit inspection terminal for detecting a detection signal for performing a short-circuit determination between second inspection target wirings, wherein the second inspection target wiring is connected to a wiring portion excluding one end and the other end thereof. A board inspection jig, comprising: a short-circuit inspection terminal that is contact-coupled.