WO2021220942A1

WO2021220942A1 - Inspection device and inspection method

Info

Publication number: WO2021220942A1
Application number: PCT/JP2021/016358
Authority: WO
Inventors: 範明高木; 慶太郡司
Original assignee: 日本電産リード株式会社
Priority date: 2020-04-28
Filing date: 2021-04-22
Publication date: 2021-11-04
Also published as: KR20230002489A; CN115485572A; TW202202862A; JPWO2021220942A1

Abstract

Provided is an inspection device and an inspection method that can easily correct variations in electrostatic capacitance due to variations in manufacture of substrates. A substrate inspection device 1 for inspecting a plurality of substrates A each having a wiring P and a reference wiring B formed thereon comprises: a measurement unit 22 that measures electrostatic capacitance of the wiring P and the reference wiring B of each substrate A as measurement capacitances C; an average capacitance calculation unit 23 that calculates, as an average capacitance Cav, an average value of the measurement capacitances C obtained from the reference wirings B provided as the same wiring in terms of design; and a capacitance correction unit 24 that calculates a corrected capacitance Cc, which is a corrected value of the measurement capacitance C of a target wiring P being inspected on a target substrate Ai, which is one of the plurality of substrates A, wherein the capacitance correction unit 24 calculates the corrected capacitance Cc by multiplying the ratio of the average capacitance Cav to the measurement capacitance C of the wiring of the target substrate Ai by the measurement capacitance C of the target wiring P.

Description

Inspection equipment and inspection method

The present invention relates to an inspection device for inspecting a substrate and an inspection method.

Conventionally, a circuit board inspection that measures the capacitance between a plurality of conductor patterns and a reference electrode in a circuit board to be measured and inspects the circuit board based on the measured capacitance between the counter electrodes. A method is known (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2003-14807

By the way, the capacitance of the wiring also changes depending on the facing area of the wiring. Therefore, if the width of the wiring, the thickness of the insulating layer, and the like vary due to variations in the manufacturing of the substrate, the capacitance of the wiring also varies.

An object of the present invention is to provide an inspection device and an inspection method that can easily correct variations in capacitance due to variations in substrate manufacturing.

The inspection device according to an example of the present invention is an inspection device that inspects a plurality of substrates on which wirings provided as the same wiring in design are formed, and the capacitance of the wiring of each substrate is used as a measurement capacitance. The measurement unit to be measured, the average capacity calculation unit that calculates the average value of the measurement capacity measured from the wiring provided as the same wiring in the design as the average capacity, and one of the plurality of substrates as the target substrate. In the case of The correction capacity is calculated by multiplying the measurement capacity of the target wiring by the ratio of the average capacity to the capacity.

Further, the inspection method according to an example of the present invention is an inspection method for inspecting a plurality of substrates on which wirings provided as the same wiring in design are formed, and measures the capacitance of the wiring of each of the substrates. The measurement step of measuring as the capacity, the average capacity calculation step of calculating the average value of the measured capacities measured from the wiring provided as the same wiring in the design as the average capacity, and one of the plurality of substrates. When the target board is used, the capacity correction step includes a capacity correction step of calculating a correction capacity which is a correction value of the measured capacity of the target wiring to be inspected on the target board, and the capacity correction step is performed on the wiring of the target board. The correction capacity is calculated by multiplying the measurement capacity of the target wiring by the ratio of the average capacity to the measurement capacity.

The inspection device and inspection method having such a configuration can easily correct the variation in capacitance due to the variation in manufacturing of the substrate.

It is a conceptual diagram which shows schematic structure of the substrate inspection apparatus which uses the inspection method which concerns on one Embodiment of this invention. It is explanatory drawing which shows an example of a panel 100. It is a top view which shows an example of the substrate A. It is explanatory drawing which shows an example of the substrate An and the example of the electric structure of the inspection part 3. It is a flowchart which shows steps S1 to S11. It is a flowchart which shows steps S21 to S30. It is a flowchart which shows the step S41-S43. It is a flowchart which shows the step S51-S58. It is a graph which shows an example of the measuring capacity C (P (1,1)) to C (P (25,5)). It is a graph which shows an example of the correction capacitance Cc (P (1,1)) to Cc (P (25,5)).

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. It should be noted that the configurations with the same reference numerals in the respective figures indicate that they are the same configurations, and the description thereof will be omitted. The substrate inspection device 1 shown in FIG. 1 is an apparatus for inspecting the wiring of the substrates A1 to A25 formed on the panel 100. The substrate inspection device 1 corresponds to an example of the inspection device.

The substrate inspection device 1 shown in FIG. 1 has a housing 11. The board fixing device 12, the inspection unit 3, the control unit 2, and the inspection unit moving mechanism 15 for appropriately moving the inspection unit 3 in the housing 11 are mainly provided in the internal space of the housing 11. ing. The board fixing device 12 is configured to fix the panel 100 to be inspected at a predetermined position.

The inspection unit 3 is located above the panel 100 fixed to the substrate fixing device 12. An inspection jig 4 for inspecting the substrate A formed on the panel 100 is attached to the inspection unit 3. A plurality of probes Pr are attached to the inspection jig 4.

The panel 100 shown in FIG. 2 includes substrates A1 to A25. Hereinafter, the substrates A1 to A25 are collectively referred to as a substrate A, and when individual substrates are indicated, a substrate number n is added to the reference numeral A and the substrate is referred to as a substrate An. The panel 100 is, for example, a panel for PLP (Panel Level Packaging).

The substrate A is, for example, a package substrate or film carrier for a semiconductor package, a printed wiring board, a glass epoxy substrate, a flexible substrate, a ceramic multilayer wiring board, an electrode plate for a display such as a liquid crystal display or an EL (Electro-Luminescence) display, and a touch panel. It may be various substrates such as a transparent conductive plate for use, a semiconductor wafer, a semiconductor chip, a semiconductor substrate such as a CSP (Chip size package), and the like. Inspection points such as wiring patterns, pads, lands, solder bumps, vias, and terminals are formed on the substrate A.

The same wiring pattern is formed on the boards A1 to A25 by design. The number of substrates A included in the panel 100 is not limited to 25. The substrate A is, for example, a substrate after the RDL is formed on the carrier and before the chip die is mounted on the RDL when a fan-out package, which is a kind of semiconductor chip package, is manufactured in the RDL (Redistribution Layer) first process. Is.

With reference to FIGS. 3 and 4, the substrate An is, for example, a multilayer substrate including a plurality of wiring layers of the first layer L1, the second layer L2, and the third layer L3. The board An has wirings P (n, 1) to P (n, 5) having wiring numbers 1 to 5 and reference wirings B (n, 1) to B (n, 3) having wiring numbers 1 to 3. It is formed. Hereinafter, the wiring of the wiring number j on the substrate Ai of the substrate number i is referred to as wiring P (i, j), and the reference wiring of the wiring number j on the substrate Ai of the substrate number i is referred to as reference wiring B (i, j). do.

Wiring P (n, 1) to P (n, 5) and reference wiring B (n, 1) to B (n, 3) correspond to an example of wiring. Hereinafter, the wirings P (n, 1) to P (n, 5) are collectively referred to as wiring Pn, and the wirings P (1,1) to P (25, 5) are collectively referred to as wiring P, which is a reference wiring. B (n, 1) to B (n, 3) are collectively referred to as reference wiring Bn, and reference wiring B (1,1) to B (25,3) are collectively referred to as reference wiring B.

The wiring P and the reference wiring B each include an end portion e and g, and a main body f connecting the end portion e and the end portion g, respectively. The ends e and g are, for example, vias and pads. The main body f extends in a strip shape and constitutes a main part of each wiring.

The end portion e of the wiring P and the reference wiring B is formed in the first layer L1. The end portion g of the wiring P and the reference wiring B is formed in the third layer L3. The main body f of the wiring P (n, 1) and the reference wiring B (n, 1) is formed in the first layer L1. The main body f of the wiring P (n, 2), P (n, 3), and the reference wiring B (n, 2) is formed in the second layer L2. The main body f of the wiring P (n, 4), P (n, 5), and the reference wiring B (n, 3) is formed in the third layer L3.

In FIG. 3, the portion formed in the first layer L1 is indicated by a solid line, the portion formed in the second layer L2 is indicated by a broken line, and the portion formed in the third layer L3 is indicated by a alternate long and short dash line.

As shown in FIG. 4, the second layer L2 of the substrate An has a planar pattern G (n, 1) formed so as to face the reference wiring B (n, 1) and spread in a planar manner. A planar pattern G (n, 3) is formed so as to be arranged so as to face the reference wiring B (n, 3) and spread in a planar manner. A planar pattern G (n, 2) is formed on the first layer L1 of the substrate An so as to be arranged to face the reference wiring B (n, 2) and spread in a planar manner.

Vias exposed on the first layer L1 are connected to the planar patterns G (n, 1) and G (n, 3). By bringing the probe Pr into contact with this via, the probe Pr can be conductively connected to the planar patterns G (n, 1) and G (n, 3). In reality, since the first layer L1 connected to the via is always arranged on the via, the probe Pr comes into contact with the via to enable a conductive connection. The influence of the capacity of the first layer L1 itself can be minimized by forming it small.

The planar patterns G (n, 1), G (n, 2), and G (n, 3) are referred to as reference wirings B (n, 1), B (n, 2), and B (n, 3). It suffices that they are arranged so as to face each other, and the arranged layers are not limited to the example shown in FIG.

The panel 100 is composed of a carrier substrate 102, a release layer 103, and a substrate A laminated in this order. The end portion e of each wiring is formed in the first layer L1, and the end portion g of each wiring is formed in the third layer L3. However, in the panel 100 after the substrate A is formed on the carrier substrate 102 and before the chip die is mounted on the substrate A, the carrier is attached to one surface (third layer L3) of the substrate A, so that the substrate It is not possible to inspect the continuity of the wiring by bringing the probe into contact with both sides of A.

Therefore, the substrate inspection device 1 has an end e, a planar pattern G (n, 2), or a planar pattern G (n, 1) on the exposed side surface (first layer L1) of the substrate A. , G (n, 3) is brought into contact with the probe Pr, and the capacitance of the wiring is measured to inspect the wiring. In reality, since the first layer L1 connected to the via is always arranged on the via, the probe Pr comes into contact with the via to enable a conductive connection. The influence of the capacity of the first layer L1 itself can be minimized by forming it small.

The panel 100 is not limited to the substrate after the substrate A is formed on the carrier and before the chip die is mounted on the substrate A.

With reference to FIG. 4, the inspection unit 3 includes a plurality of probe Prs, a scanner unit 31, an AC power supply 32, and a plurality of ammeters 33. Each probe Pr, one end of the AC power supply 32, one end of each ammeter 33, and the circuit ground are connected to the scanner unit 31. The other end of the AC power supply 32 and the other end of each ammeter 33 are connected to the circuit ground.

The scanner unit 31 is a switching circuit configured by using a switching element such as a transistor or a relay switch. The scanner unit 31 connects the AC power supply 32 and each ammeter 33 to an arbitrary probe Pr in response to the control signal from the control unit 2.

The AC power supply 32 is an AC power supply circuit that outputs an AC voltage V having a preset frequency f to the probe Pr via the scanner unit 31. The ammeter 33 is an AC ammeter configured by using, for example, a shunt resistor, a Hall element, an analog-digital converter, or the like. The ammeter 33 measures the current I flowing from the probe Pr connected via the scanner unit 31 to the circuit ground, and transmits a signal indicating the current I to the control unit 2. The voltage V and the current I may be effective values or peak values.

With reference to FIG. 1, the control unit 2 stores, for example, a CPU (Central Processing Unit) that executes a predetermined logical operation, a RAM (Random Access Memory) that temporarily stores data, a predetermined control program, and the like in advance. It is configured by using a non-volatile storage device and a microcomputer equipped with peripheral circuits thereof and the like.

The control unit 2 functions as an inspection control unit 21, a measurement unit 22, an average capacity calculation unit 23, a capacity correction unit 24, a reference value calculation unit 25, and a determination unit 26, for example, by executing the above-mentioned control program.

The inspection control unit 21 appropriately moves the inspection unit 3 to bring each probe Pr into contact with each inspection point such as an end e on the substrate A fixed to the substrate fixing device 12.

The measuring unit 22 measures the capacitance of the wiring of each substrate A as the measuring capacitance. Specifically, the measuring unit 22 measures the capacitance between the reference wiring B (n, 1) and the planar pattern G (n, 1) as the measurement capacitance of the reference wiring B (n, 1). , The capacitance between the reference wiring B (n, 2) and the planar pattern G (n, 2) is measured as the measured capacitance of the reference wiring B (n, 2), and the reference wiring B (n, 3) is measured. The capacitance between the surface pattern G (n, 3) and the planar pattern G (n, 3) is measured as the measurement capacitance of the reference wiring B (n, 3).

Strictly speaking, the capacitance measured by bringing the probe Pr into contact with the reference wiring B (n, 1) and the planar pattern G (n, 1) includes the capacitance around the reference wiring B (n, 1). It also includes the capacitance generated between the material and the material. Similarly, the capacitance measured by bringing the probe Pr into contact with the reference wiring B (n, 2) and the planar pattern G (n, 2) includes the material around the reference wiring B (n, 2). The capacitance generated between the two is also included, and the capacitance measured by bringing the probe Pr into contact with the reference wiring B (n, 3) and the planar pattern G (n, 3) includes the reference wiring B. The capacitance generated between the material around (n, 3) is also included.

However, the capacitance is inversely proportional to the distance and proportional to the area. Therefore, if the reference wiring B (n, 1), B (n, 2), B (n, 3) and the wiring around it are separated from each other, the reference wiring B (n, 1) having a large area has a large area. Capacitance between the surface pattern G (n, 1) and the reference wiring B (n, 2), and the capacitance between the reference wiring B (n, 2) and the surface pattern G (n, 2), and the reference wiring B (n, n). , 3) and the planar pattern G (n, 3) dominate.

Therefore, the capacitance measured by bringing a pair of probes Pr into contact with the reference wiring B (n, 1) and the planar pattern G (n, 1) is the capacitance of the reference wiring B (n, 1). The capacitance measured by bringing a pair of probes Pr into contact with the reference wiring B (n, 2) and the planar pattern G (n, 2) can be approximated as the reference wiring B (n, 2). ) Can be approximated, and the capacitance measured by bringing a pair of probes Pr into contact with the reference wiring B (n, 3) and the planar pattern G (n, 3) is used as the reference wiring. It can be approximated as the capacitance of B (n, 3).

Further, the capacitance of the wiring Pn may be the capacitance between the wiring Pn and all other wirings and patterns, and the wiring Pn and one or more other presets. It may be the capacitance between the wiring or the pattern. Alternatively, when the carrier substrate 102 is a conductor substrate, the capacitance of the wiring Pn may be the capacitance between the wiring Pn and the carrier substrate 102. The measuring unit 22 may use the capacitance measured between the wiring Pn and the pair of probes Pr in contact with the arbitrarily set wiring or pattern as the measurement capacitance of the wiring Pn.

The measuring unit 22 connects the ammeter 33 to the probe Pr that comes into contact with the reference wiring Bn or the wiring Pn to be measured by the scanner unit 31. Further, the measuring unit 22 connects the AC power supply 32 to the probe Pr paired with the probe Pr by the scanner unit 31.

Then, the voltage V of the frequency f output from the AC power supply 32 causes a current I to flow through the capacitance of the reference wiring Bn or the wiring Pn to be measured, and the current I is measured by the current meter 33.

When the current I flows when the voltage V of the frequency f is applied to the capacitance X, the capacitance X is given by the following equation (1).
Capacitance X = I / (V × 2πf) ・・・ (1)

In this case, since V and 2πf are known, the capacitance X can be known if the current I is obtained. Therefore, the measuring unit 22 can measure the capacitance X as the measuring capacitance C.

Hereinafter, the measuring unit 22 measures the capacitance X using the scanner unit 31, the AC power supply 32, and the ammeter 33, and the measuring unit 22 simply measures the capacitance X, that is, the measuring capacity C. , And so on.

The average capacity calculation unit 23 calculates the average value of the measurement capacity C measured from the wirings corresponding to each other as the average capacity Cav. The wiring corresponding to each other is a wiring created as the same wiring in the design for each substrate A. For example, the reference wirings B (1,1), B (2,1), B (3,1), ... B (2,2), B (3,2), ... Are wirings corresponding to each other, and reference wirings B (1,3), B (2,3), B (3,3), ... -Is the wiring corresponding to each other.

When the substrate Ai of the substrate number i is used as the target substrate among the plurality of substrates A1 to A25, the capacitance correction unit 24 determines the ratio of the average capacitance Cav to the measured capacitance Ci of the wiring of the target substrate Ai of the target substrate Ai. By multiplying the measurement capacity C of the target wiring to be inspected, the correction capacity Cc, which is the correction value of the measurement capacity C of the target wiring, is calculated.

Further, the capacitance correction unit 24 calculates the correction capacitance Cc for the target wiring of each substrate A by sequentially using each substrate A as the target substrate.

The reference value calculation unit 25 calculates the average value of the correction capacitance Cc for the target wiring of each substrate A as the determination reference value Clef.

The determination unit 26 determines the correction capacity Cc based on the determination reference value Clef.

Next, an example of the operation of the substrate inspection device 1 that executes the inspection method according to the example of the present invention will be described with reference to FIGS. 5 to 8. In the following description, the measurement capacity of the reference wiring B (i, j) is C (B (i, j)), the measurement capacity of the wiring P (i, j) is C (P (i, j)), and the wiring P. The correction capacitance of (i, j) is described as Cc (P (i, j)).

First, the measuring unit 22 initializes the board number i to 1 (step S1).

Next, the inspection control unit 21 brings each probe Pr into contact with the first layer L1 of the substrate Ai. Specifically, each probe Pr is provided with reference wiring B (i, 1) to B (i, 3), wiring P (i, 1) to P (i, 5), and planar pattern G (i, 1). -G (i, 3) and wiring P (i, 1)-P (i, 5) are brought into contact with any wiring or the like paired with each other (step S2).

Next, the measuring unit 22 has a measuring capacity C (B (i, 1)), a C (B (i, 2), a C (B (i, 3), and a measuring capacity C (P (i, 1))). , C (P (i, 2)), C (P (i, 3)), C (P (i, 4)), C (P (i, 5)) (step S2: measurement step) ..

Next, the measuring unit 22 compares the substrate number i with 25 (step S3), and if the substrate number i is not 25 (NO in step S3), 1 is added to the substrate number i to measure the new substrate A. Addition (step S4), and steps S2 and S3 are repeated again. On the other hand, if the substrate number i is 25 (YES in step S3), the measurement capacitance C has been measured for all the wirings, so the process proceeds to step S5.

Next, the average capacity calculation unit 23 measures the average value of the measurement capacities C (B (1,1)) to C (B (25,1)) as the average capacity Cav (L1) of the first layer L1. The average value of the capacities C (B (1,2)) to C (B (25,2)) is defined as the average capacity Cav (L2) of the second layer L2, and the measurement capacities C (B (1,3)) to Let the average value of C (B (25,3)) be the average capacity Cav (L3) of the third layer L3 (step S5: average capacity calculation step).

The measurement capacities C (B (1,1)) to C (B (25,1)) are reference wirings B having wiring numbers 1 corresponding to each other, and are from the reference wiring B formed in the first layer L1. The measured measurement capacity C. The measurement capacities C (B (1,2)) to C (B (25,2)) are reference wirings B having wiring numbers 2 corresponding to each other, and are from the reference wiring B formed in the second layer L2. The measured measurement capacity C. The measurement capacities C (B (1,3)) to C (B (25,3)) are reference wirings B having wiring numbers 3 corresponding to each other, and are from the reference wiring B formed in the third layer L3. The measured measurement capacity C.

Although one reference wiring B is provided for each layer on one substrate A, a plurality of reference wirings B may be provided for each layer. Then, the average capacities Cav (L1), Cav (L2), and Cav (L3) may be calculated by averaging the measurement capacities C of the plurality of reference wirings B for each substrate for each of the plurality of substrates and for each layer.

Next, the capacitance correction unit 24 initializes the board number i to 1 (step S6).

Next, the capacitance correction unit 24 calculates the correction capacitance Cc (P (i, 1)) of the wiring P (i, 1) of the first layer L1 based on the following equation (1) (step S7: Capacity correction process). Correction capacity Cc (P (i, 1)) = C (P (i, 1)) x Cav (L1) / C (B (i, 1)) ... (1)

In step S7, the board Ai corresponds to the target board, the wiring P (i, 1) corresponds to the target wiring of the first layer L1, and the reference wiring B (i, 1) corresponds to the wiring of the target board Ai. Cav (L1) / C (B (i, 1)) corresponds to the ratio of the average capacity Cav (L1) to the measured capacity C (B (i, 1)) of the wiring of the target substrate Ai.

Next, the capacitance correction unit 24 uses the correction capacitances Cc (P (i, 2)) and Cc (P (i, 3)) of the wirings P (i, 2) and P (i, 3) of the second layer L2. Is calculated based on the following equations (2) and (3) (step S8: capacity correction step).
Correction capacity Cc (P (i, 2)) = C (P (i, 2)) × Cav (L2) / C (B (i, 2)) ・・・ (2)
Correction capacity Cc (P (i, 3)) = C (P (i, 3)) x Cav (L2) / C (B (i, 2)) ... (3)

In step S8, the board Ai corresponds to the target board, the wirings P (i, 2) and P (i, 3) correspond to the target wiring of the second layer L2, and the reference wiring B (i, 2) corresponds to the target board. Corresponds to the wiring of Ai, and Cav (L2) / C (B (i, 2)) corresponds to the ratio of the average capacitance Cav (L2) to the measured capacitance C (B (i, 2)) of the wiring of the target substrate Ai. do.

Next, the capacitance correction unit 24 uses the correction capacitances Cc (P (i, 4)) and Cc (P (i, 5)) of the wirings P (i, 4) and P (i, 5) of the third layer L3. Is calculated based on the following equations (4) and (5) (step S9: capacity correction step).
Correction capacity Cc (P (i, 4)) = C (P (i, 4)) x Cav (L3) / C (B (i, 3)) ... (4)
Correction capacity Cc (P (i, 5)) = C (P (i, 5)) x Cav (L3) / C (B (i, 3)) ... (5)

In step S9, the board Ai corresponds to the target board, the wirings P (i, 4) and P (i, 5) correspond to the target wiring of the third layer L3, and the reference wiring B (i, 3) corresponds to the target board. Corresponds to the wiring of Ai, and Cav (L3) / C (B (i, 3)) corresponds to the ratio of the average capacity Cav (L3) to the measured capacity C (B (i, 3)) of the wiring of the target substrate Ai. do.

Next, the capacitance correction unit 24 compares the substrate number i with 25 (step S10), and if the substrate number i is not 25 (NO in step S10), the capacitance correction unit 24 sets the substrate number i to 1 in order to correct the new substrate A. Is added (step S11), and steps S7 to 10 are repeated again. On the other hand, if the substrate number i is 25 (YES in step S10), it means that all the measurement capacities C have been corrected, so the process proceeds to step S21.

As shown in FIG. 9, even if the wirings P have the same wiring number, the measurement capacity C varies from substrate A to substrate A. The measurement capacity C decreases when the wiring P is broken, and increases when the wiring P is short-circuited with other wiring or the like. If there is no variation in the substrate, it is possible to determine whether the wiring P is broken or short-circuited by increasing or decreasing the measurement capacity C.

However, as shown in FIG. 9, if the variation of the measurement capacity C due to the variation of the substrate is large, it is not easy to determine the disconnection or short circuit of the wiring P based on the measurement capacitance C.

For example, in the measurement capacity C (P (2,2)) shown in FIG. 9, the measurement capacity C (P (2,2)) when the wiring P (2,2) is broken is a solid line, and the wiring P ( The measured capacity C (P (2,2)) when 2 and 2) are normal is shown by a broken line. In the example shown in FIG. 9, the measurement capacity C (P (2, 2)) when the wiring P (2, 2) is broken is the measurement capacity C (P (P (2)) of the normal wiring P (1, 2). It is smaller than 1,2)) and larger than the measurement capacity C (P (25,2)) of the normal wiring P (25,2). Therefore, it is difficult to determine that the wiring P (2, 2) is defective based on the measurement capacity C (P (2, 2)).

As shown in FIG. 10, the correction capacitances Cc (P (1,1)) to Cc (P (25,5)) corrected in steps S7 to S9 have the same wiring number if the wiring P is normal. In the wirings P corresponding to each other, the influence of the variation of the substrate is reduced, and the capacitance becomes substantially the same. As described above, according to steps S1 to S11, it becomes easy to correct the variation in the capacitance X due to the manufacturing variation in the substrate A.

Further, in the manufacturing process of the substrate A, since the wiring P and the reference wiring B are formed for each layer, the variation may differ for each layer even within the same substrate A. Therefore, in step S2, the measurement capacities C (B (1,1)) to C (B (25,3)) are obtained from the reference wirings B (n, 1) to B (n, 3) provided in each layer. Be measured. In step S5, the average capacities Cav (L1), Cav (L2), and Cav (L3) are calculated for each layer. In steps S7 to S9, the measurement capacities C (P (1,1)) to C (P (25,5)) are corrected for each layer, and the correction capacities Cc (P (1,1)) to Cc (P (P (P)). 25,5)) is calculated.

Thereby, the correction capacities Cc (P (1,1)) to Cc (P (25,5)) can be calculated so as to reduce the difference in the variation for each layer.

Next, in step S21, the reference value calculation unit 25 uses the average value of the correction capacitances Cc (P (1,1)) to C (P (25,1)) as the determination reference for the wiring P (n, 1). The value Clef (1) is set, and the average value of the correction capacities Cc (P (1,2)) to Cc (P (25,2)) is set as the judgment reference value Clef (2) of the wiring P (n, 2). The average value of the correction capacitances Cc (P (1,3)) to Cc (P (25,3)) is set as the judgment reference value Clef (3) of the wiring P (n, 3), and the correction capacitance Cc (P (1)) is used. , 4)) to Cc (P (25,4)) is set as the judgment reference value Clef (4) of the wiring P (n, 4), and the correction capacitances Cc (P (1,5)) to Cc ( Let the average value of P (25,5)) be the determination reference value Clef (5) of the wiring P (n, 5) (step S21: reference value calculation step).

Next, the determination unit 26 initializes the board number i and the wiring number j to 1 (step S22).

Next, if the absolute value of {Cc (P (i, j))-Clef (j)} / Clef (j) is equal to or less than the determination ratio Ref (YES in step S23), the determination unit 26 determines the wiring P. If (i, j) is determined to be good (step S24) and the determination ratio Ref is exceeded (NO in step S23), the wiring P (i, j) is determined to be defective (step S25).

That is, when the ratio of the difference between the correction capacitance Cc of each wiring P and the determination reference value Clef with respect to the determination reference value Clef exceeds the preset determination ratio Ref, the determination unit 26 determines that the wiring P is defective. can do. The determination ratio Ref may be appropriately set according to the required inspection accuracy.

Next, the determination unit 26 compares the wiring number j with 5 (step S26), and if the wiring number j is not 5 (NO in step S26), the wiring number j is used to determine another wiring P on the board Ai. 1 is added to (step S27), and steps S23 to S26 are repeated again.

On the other hand, if the wiring number j is 5 (YES in step S26), the board number i is compared with 25 (step S28), and if the board number i is not 25 (NO in step S28), the new board A is In order to determine, 1 is added to the board number i, the wiring number j is initialized to 1 (step S29), and steps S23 to 28 are repeated again.

On the other hand, if the board number i is 25 (YES in step S28), it means that the quality of all wiring P has been determined, so the process proceeds to step S30.

In step S30, the determination unit 26 confirms whether or not there is a wiring P determined to be defective in step S25 (step S30). If there is no wiring P determined to be defective (NO in step S30), the process ends.

On the other hand, if there is even one wiring P determined to be defective (YES in step S30), the process proceeds to step S41.

If there is even one wiring P determined to be defective (YES in step S30), the average value calculated in step S21 including the correction capacity Cc of the defective wiring P is used as the determination reference value Clef. Therefore, the quality judgment accuracy of the wiring P based on the judgment reference value Clef is lowered.

Therefore, in step S41, the reference value calculation unit 25 corrects the remainder by removing the correction capacity of the wiring determined to be defective from the correction capacities Cc (P (1,1)) to C (P (25,1)). Let the average value of the capacitance be the new judgment reference value Clef (1) of the wiring P (n, 1).

Similarly, the reference value calculation unit 25 averages the remaining correction capacities excluding the correction capacities of the wiring determined to be defective from the correction capacities Cc (P (1,2)) to C (P (25,2)). Let the value be the new determination reference value Clef (2) of the wiring P (n, 2) (step S41).

The reference value calculation unit 25 calculates the average value of the residual correction capacity obtained by excluding the correction capacity of the wiring determined to be defective from the correction capacities Cc (P (1,3)) to C (P (25,3)). Set the new determination reference value Clef (3) of the wiring P (n, 3) (step S41).

The reference value calculation unit 25 calculates the average value of the residual correction capacity obtained by excluding the correction capacity of the wiring determined to be defective from the correction capacities Cc (P (1,4)) to C (P (25,4)). The new determination reference value Clef (4) of the wiring P (n, 4) is set (step S41).

The reference value calculation unit 25 calculates the average value of the residual correction capacity obtained by excluding the correction capacity of the wiring determined to be defective from the correction capacities Cc (P (1,5)) to C (P (25,5)). Set the new determination reference value Clef (5) of the wiring P (n, 5) (step S41).

According to step S41, when there is a defective wiring, a new determination reference value Clef can be obtained based on the residual correction capacitance excluding the correction capacitance of the defective wiring. Therefore, the accuracy of the determination reference value Clef can be determined. Can be improved.

Next, the determination unit 26 initializes the board number i and the wiring number j to 1 (step S42).

Next, the determination unit 26 confirms in step S25 whether or not the wiring P (i, j) is defective (step S43). If the wiring P (i, j) is not defective (NO in step S43), the determination unit 26 shifts the process to step S51. If the wiring P (i, j) is defective (YES in step S43), the determination unit 26 shifts the process to step S54.

In step S51, the determination unit 26 determines that the absolute value of {Cc (P (i, j))-Clef (j)} / Clef (j) is equal to or less than the determination ratio Ref based on the new determination reference value Clef. If there is (YES in step S51), the wiring P (i, j) is determined to be good (step S52), and if the determination ratio Ref is exceeded (NO in step S51), the wiring P (i, j) is defective. (Step S53).

Next, the determination unit 26 compares the wiring number j with 5 (step S54), and if the wiring number j is not 5 (NO in step S54), the determination unit 26 determines the other wiring P on the board Ai. 1 is added to (step S55), and steps S51 to 54 are repeated again.

On the other hand, if the wiring number j is 5 (YES in step S54), the board number i is compared with 25 (step S56), and if the board number i is not 25 (NO in step S56), the new board A is In order to determine, 1 is added to the board number i, the wiring number j is initialized to 1 (step S57), and steps S51 to 56 are repeated again.

On the other hand, if the board number i is 25 (YES in step S56), it means that all the wirings P that were not defective last time have been judged to be good or bad based on the new judgment reference value Clef, so that step S58 Move the process to.

In step S58, the determination unit 26 confirms whether or not there is a wiring P newly determined to be defective in step S53 (step S58). If there is no wiring P newly determined to be defective (NO in step S58), the process ends.

On the other hand, if there is at least one wiring P newly determined to be defective (YES in step S58), steps S41 to S58 are repeated again.

As described above, according to the processes of steps S30 and S41 to S58, when there is a wiring P determined to be defective, the influence of the wiring P determined to be defective is eliminated, and the determination reference value Clef is newly calculated. Since the quality determination of the wiring P, which has been determined to be a non-defective product, is redone based on the newly calculated determination reference value Clef, the quality determination accuracy of the wiring P is improved.

It is not always necessary to execute steps S30 to S53, and if YES in step S28, the process may be terminated.

Further, the reference wiring B is not limited to the example of being provided for each layer of the substrate A. For example, only the reference wiring B (n, 2) is provided as the reference wiring, and in steps S7 and S9, Cav (L1) / C (B (i, 1)) and Cav (L3) / C (B (i, 3)) are provided. )) May be used instead of Cav (L2) / C (B (i, 2)).

Also, the example is not limited to the case where the reference wiring B is provided separately from the wiring P to be inspected. The reference wiring B may not be provided, and any of the wirings P may be used instead of the reference wiring B. For example, the wirings P (n, 2) and P (n, 4) may be used instead of the reference wirings B (n, 2) and B (n, 3).

In this case, in step S5, the average value of the measurement capacities C (P (1,2)) to C (P (25,2)) is set as the average capacitance Cav (L2) of the second layer L2, and the measurement capacitance C ( The average value of P (1,4)) to C (P (25,4)) can be defined as the average capacity Cav (L3) of the third layer L3. Further, in step S8, the measurement capacity C (P (i, 2)) is used instead of the measurement capacity C (B (i, 2)), and in step S9, the measurement capacity C (B (i, 3)) is replaced. The measurement capacity C (P (i, 4)) can be used.

As a result, although the wirings P (n, 2) and P (n, 4) cannot be inspected in steps S23 to S25 and steps S51 to S53, the wirings P (n, 3) and P (n, 5) cannot be inspected. Can be inspected. When inspecting the wiring P (n, 2), P (n, 4), instead of the reference wiring B (n, 2), B (n, 3), the wiring P (n, 3), P ( n, 5) may be used.

In this way, it is not necessary to provide the reference wiring B separately from the wiring P. On the other hand, the wiring P that is routed to form the circuit tends to be routed in a complicated manner, tends to have a complicated shape, and the capacitance X tends to become unstable. However, when the reference wiring B is provided separately from the wiring P, the reference wiring B for calculating the average capacitance should be shaped and arranged so that the capacitance is easy to stabilize, regardless of the necessity in the circuit. Is easy.

Further, the substrate inspection apparatus and inspection method according to the present invention need only be able to easily correct the variation in capacitance due to the variation in manufacturing of the substrate, and YES in step S10 without executing steps S21 to S58. In the case of, the process may be terminated.

Further, although the wiring P once determined to be defective in step S43 is not determined again in steps S51 to S53, the wiring P may be shifted from step S42 to step S51 without executing step S43.

That is, the inspection device according to an example of the present invention is an inspection device that inspects a plurality of substrates on which wirings provided as the same wiring in design are formed, and measures the capacitance of the wiring of each of the substrates. A measurement unit that measures as a capacity, an average capacity calculation unit that calculates the average value of the measurement capacity measured from the wiring provided as the same wiring in the design as an average capacity, and one of the plurality of substrates. When the target board is used, the target board is provided with a capacitance correction unit that calculates a correction capacity which is a correction value of the measurement capacity of the target wiring to be inspected, and the capacitance correction unit is a wiring of the target board. The correction capacity is calculated by multiplying the measurement capacity of the target wiring by the ratio of the average capacity to the measurement capacity.

According to these configurations, the capacitance of the wiring of each board is measured as the measurement capacity, and the average value of the measurement capacities measured from the wirings corresponding to each other provided as the same wiring in the design is calculated as the average capacity. NS. Then, the ratio of the average capacity to the measured capacity of the wiring of the target board, which is one of the plurality of boards, is multiplied by the measured capacity of the target wiring to be inspected on the target board to calculate the correction capacity of the target wiring. NS. As a result, the variation in the correction capacitance between the substrates is reduced, so that it becomes easy to correct the variation in the capacitance due to the manufacturing variation of the substrate.

Further, the capacitance correction unit calculates the correction capacitance of the target wiring of each target substrate using the plurality of substrates as the target substrates, and the inspection device sets the average value of the correction capacitances as a determination reference value. It is preferable to further include a reference value calculation unit for calculating as, and a determination unit for determining each correction capacity based on the determination reference value.

According to this configuration, the determination reference value can be automatically calculated based on the correction capacity of the target wiring of each target board, so that each correction capacity can be easily determined.

Further, the reference value calculation unit calculates the average value of the residual correction capacity excluding the correction capacity determined to be defective by the determination unit as a new determination reference value, and the determination unit calculates the new determination. It is preferable to determine at least the residual correction capacity based on the reference value.

According to this configuration, the correction capacity of the defective wiring is excluded from the data that is the source of the judgment reference value, and a new judgment reference value is calculated, so that the judgment accuracy based on the new judgment reference value is improved.

Further, the wiring includes a reference wiring that is not an inspection target and is provided as the same wiring in design between the plurality of substrates, and the measuring unit uses the capacitance of the reference wiring as the reference wiring. It is preferable that the measurement is performed as the measurement capacity, and the average capacity calculation unit calculates the average value of the measurement capacities of the reference wiring on each substrate as the average capacity.

According to this configuration, the average capacity is calculated based on the measured capacity measured from the reference wiring different from the wiring to be inspected. The wiring to be inspected that is routed to form a circuit tends to be routed in a complicated manner, tends to have a complicated shape, and the capacitance tends to be unstable. However, if a reference wiring is provided separately from the wiring to be inspected, the reference wiring for calculating the average capacitance should be shaped and arranged so that the capacitance is easy to stabilize, regardless of the necessity in the circuit. Is easy.

Further, it is preferable that the substrate is a multilayer substrate and the reference wiring is provided for each layer of the substrate.

In the substrate manufacturing process, wiring and reference wiring are formed for each layer, so even within the same substrate, the variation may differ for each layer. Therefore, by providing the reference wiring for each layer of the substrate, it becomes easy to calculate the correction capacitance so as to reduce the difference in the variation for each layer.

Further, it is preferable that a probe for contacting the wiring is provided, and the measuring unit measures the capacitance via the probe.

According to this configuration, the capacitance of the wiring can be measured by bringing the probe into contact with the wiring.

1 Board inspection device, 2 Control unit, 3 Inspection unit, 4 Inspection jig, 11 Housing, 12 Board fixing device, 15 Inspection unit movement mechanism, 21 Inspection control unit, 22 Measurement unit, 23 Average capacity calculation unit, 24 Capacity Correction unit, 25 reference value calculation unit, 26 judgment unit, 31 scanner unit, 32 AC power supply, 33 ammeter, 100 panel, 102 carrier board, 103 peeling layer, A, A1 to A25 board, B reference wiring, C measurement capacity , Cav average capacity, Cc correction capacity, Clef judgment reference value, G surface pattern, I current, L1 first layer, L2 second layer, L3 third layer, P wiring, Pr probe, Ref judgment ratio, V e, g, end, f, main body, X, capacitance

Claims

It is an inspection device that inspects a plurality of substrates on which wirings provided as the same wiring in design are formed.
A measuring unit that measures the capacitance of the wiring of each substrate as the measuring capacitance,
An average capacity calculation unit that calculates the average value of the measured capacities measured from the wiring provided as the same wiring in the design as the average capacity.
When one of the plurality of substrates is used as the target substrate, a capacitance correction unit for calculating the correction capacitance, which is a correction value of the measurement capacitance of the target wiring to be inspected on the target substrate, is provided.
The capacity correction unit is an inspection device that calculates the correction capacity by multiplying the measurement capacity of the target wiring by the ratio of the average capacity to the measurement capacity of the wiring of the target substrate.
The capacitance correction unit calculates the correction capacitance of the target wiring of each of the target boards by using the plurality of boards as the target boards.
The inspection device includes a reference value calculation unit that calculates an average value of each correction capacity as a determination reference value.
The inspection device according to claim 1, further comprising a determination unit for determining each correction capacity based on the determination reference value.
The reference value calculation unit calculates the average value of the residual correction capacity excluding the correction capacity determined to be defective by the determination unit as a new determination reference value.
The inspection device according to claim 2, wherein the determination unit determines at least the residual correction capacity based on the new determination reference value.
The wiring includes a reference wiring that is not subject to inspection and is provided as the same wiring in design between the plurality of substrates.
The measuring unit measures the capacitance of the reference wiring as the measurement capacitance of the reference wiring.
The inspection device according to any one of claims 1 to 3, wherein the average capacity calculation unit calculates an average value of the measured capacities of the reference wiring on each substrate as the average capacity.
The substrate is a multilayer substrate and
The inspection device according to claim 4, wherein the reference wiring is provided for each layer of the substrate.
Provided with a probe for contacting the wiring
The inspection device according to any one of claims 1 to 5, wherein the measuring unit measures the capacitance via the probe.
This is an inspection method that inspects a plurality of boards on which wirings provided as the same wiring in design are formed.
A measurement step of measuring the capacitance of the wiring of each substrate as a measurement capacitance,
An average capacity calculation step of calculating the average value of the measured capacities measured from the wiring provided as the same wiring in the design as the average capacity, and
When one of the plurality of substrates is used as the target substrate, a capacitance correction step of calculating a correction capacity which is a correction value of the measured capacitance of the target wiring to be inspected on the target substrate is included.
The capacity correction step is an inspection method for calculating the correction capacity by multiplying the measurement capacity of the target wiring by the ratio of the average capacity to the measurement capacity of the wiring of the target substrate.