JP5595234B2 - Multilayer circuit board and layer displacement measurement system - Google Patents

Description

  The present invention relates to a multilayer circuit board having a multilayer structure, and more particularly to a multilayer circuit board having a conductor pattern for detecting a layer shift, and a layer shift measurement system.

  A conventional method of detecting layer misalignment in a multilayer circuit board is to create a conductor pattern on the multilayer circuit board to detect the layer misalignment and measure the capacitance change between flat plates due to layer misalignment using an external measuring instrument. Alternatively, a method of measuring a change in resonance frequency accompanying a change in capacitance is used (for example, see Patent Document 1).

Japanese Patent No. 4451208

However, the prior art has the following problems.
Resin substrates have poor dielectric constant reproducibility due to manufacturing processes, humidity, aging, and the like. For this reason, there is a problem that the error increases in the method using the change in the capacitance and the resonance frequency as it is.

  The present invention has been made to solve the above-described problems, and provides a multilayer circuit board and a layer displacement measuring system capable of measuring the amount of displacement with high accuracy regardless of the dielectric constant of the substrate material. The purpose is to obtain.

A multilayer circuit board according to the present invention includes a first conductor pattern provided on a specific first layer of a multilayer structure, and a second conductor pattern provided on a specific second layer different from the first layer of the multilayer structure. The first conductor pattern is disposed opposite to the second conductor pattern, has a smaller area than the second conductor pattern, and is the largest in the stacking of the first layer and the second layer. It is designed not to protrude from the second conductor pattern even when misalignment occurs. The second conductor pattern is divided into a plurality of conductor patterns by slits, and the first conductor pattern and the divided conductor pattern are divided. Each of the plurality of conductor patterns is provided with a terminal for measuring the capacitance between the conductor patterns , and the second conductor pattern is divided into two by one slit .

The layer misalignment measurement system according to the present invention is connected to the multilayer circuit board, the terminals provided in the first conductor pattern of the multilayer circuit board, and the respective terminals provided in the plurality of divided conductor patterns. Each capacitance value between the first conductor pattern and the plurality of conductor patterns is measured, and a value that does not depend on the dielectric constant of the substrate is converted to a ratio with the other capacitance value based on the measured one capacitance value. And a displacement amount detector for calculating a displacement amount due to the lamination of the first layer and the second layer.

In addition, the layer misalignment measurement system according to the present invention is connected to the multilayer circuit board, the first conductor pattern of the multilayer circuit board, and the inductor, and to each terminal provided in the plurality of divided conductor patterns. It is connected and does not depend on the dielectric constant of the substrate measured for each resonance frequency between the first conductor pattern and the plurality of conductor patterns, and converted into a ratio to the other resonance frequency based on the measured one resonance frequency. A displacement amount detector that calculates a displacement amount due to the lamination of the first layer and the second layer using the value is provided.

  According to the multilayer circuit board and the layer misalignment measuring system of the present invention, the first conductor pattern is provided on the first layer in the multilayer circuit board, the second conductor pattern divided by the slit is provided on the second layer, A multilayer circuit board capable of measuring the amount of deviation with high accuracy regardless of the dielectric constant of the substrate material by calculating the ratio and measuring the layer deviation based on the measurement result of the capacitance or the resonance frequency, and A layer displacement measurement system can be obtained.

It is a top view of the conductor pattern provided in the specific 1st layer and 2nd layer of the multilayer circuit board which concerns on Embodiment 1 of this invention. It is a side view of the conductor pattern provided in the specific 1st layer and 2nd layer of the multilayer circuit board which concerns on Embodiment 1 of this invention. It is a top view when a layer shift occurs in the multilayer circuit board according to Embodiment 1 of the present invention. It is a side view when a layer shift has occurred in the multilayer circuit board according to Embodiment 1 of the present invention. 1 is a schematic diagram of a layer displacement measurement system applied to a multilayer circuit board according to Embodiment 1 of the present invention. It is a schematic diagram of the layer shift measuring system applied to the multilayer circuit board according to Embodiment 2 of the present invention. It is a top view of the conductor pattern provided in the specific 1st layer and 2nd layer of the multilayer circuit board which concerns on Embodiment 3 of this invention. It is a top view when a layer shift occurs in the multilayer circuit board according to Embodiment 3 of the present invention. FIG. 8 is a top view when the layer shift of FIG. 7 occurs.

  Hereinafter, preferred embodiments of a multilayer circuit board and a layer displacement measuring system of the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
1 and 2 are a top view and a side view of conductor patterns provided on a specific first layer and a second layer of the multilayer circuit board according to Embodiment 1 of the present invention. 3 and 4 are a top view and a side view when a layer shift occurs in the multilayer circuit board according to Embodiment 1 of the present invention. FIG. 3 illustrates a state in which the conductor pattern 1 is shifted leftward in the drawing with respect to the conductor patterns 2a and 2b.

  The multilayer circuit board according to the first embodiment includes a conductor pattern 1 provided on the first layer, conductor patterns 2a and 2b provided on the second layer, and a slit 3a. The conductor pattern 1 is a conductor pattern provided in a certain layer (corresponding to a specific first layer) of the multilayer circuit board, and the conductor patterns 2a and 2b are layers different from the conductor pattern 1 (specific second layer). The conductor pattern is divided into two by the slit 3a.

  The size of the conductor pattern 1 in the first embodiment is smaller than the combined size of the conductor patterns 2a and 2b. Even when a layer shift occurs between the first layer and the second layer, the conductor pattern 1 is designed not to protrude from the conductor patterns 2a and 2b when viewed as a top view. .

  With the above configuration, two capacitors are formed between the conductor pattern 1 and the conductor patterns 2a and 2b using the conductor pattern 1 as a common electrode. FIG. 5 is a schematic diagram of a layer displacement measurement system applied to the multilayer circuit board according to Embodiment 1 of the present invention. The deviation amount detector 4a shown in FIG. 5 has a function of measuring the capacitances of the two capacitors, calculating the ratio thereof, and converting it to the deviation amount.

  Although not shown in FIG. 5, each of the conductor pattern 1 and the two-divided conductor patterns 2a and 2b is provided with an input / output terminal for measuring the capacitance by the deviation amount detector 4a. .

  Next, a specific operation of the layer displacement measuring system shown in FIG. 5 in Embodiment 1 of the present invention will be described. When the layer shift occurs, as shown in FIGS. 3 and 4, the position of the slit 3a between the conductor patterns 2a and 2b is displaced from the state shown in FIGS. Thereby, each area which the conductor pattern 1 and the conductor patterns 2a and 2b oppose changes. As a result, the capacitance values of the two capacitors measured by the deviation amount detector 4a of the measurement system of FIG. 5 also change corresponding to the area change.

  Here, the capacitance between the conductor pattern 1 and the conductor pattern 2a and the capacitance between the conductor pattern 1 and the conductor pattern 2b are both proportional to the dielectric constant of the substrate. Generally used resin substrates such as FR4 have poor reproducibility of the dielectric constant due to the manufacturing process, humidity, aging, etc., and therefore the measured capacitance value itself has poor reproducibility. However, by taking the ratio of the capacitance values measured for the two capacitors, the influence of the dielectric constant is canceled, and the value can be made independent of the dielectric constant of the substrate.

  If the capacitance value is proportional to the opposing area, the capacitance ratio and the area ratio are equal. Therefore, the position of the slit 3a with respect to the conductor pattern 1 can be geometrically determined such that the slit is at a position where the area of the conductor pattern 1 is divided into the same ratio as the capacitance ratio. Thereby, the positional relationship between the specific first layer and the second layer of the multilayer circuit board can be determined. That is, in FIG. 3, from the ratio of the area of the conductor pattern 1 to each of the conductor patterns 2a and 2b divided by the slit 3a, the direction orthogonal to the direction of the slit 3a (corresponding to the left and right direction on the paper surface of FIG. 3). The amount of layer shift can be determined.

  As described above, according to the first embodiment, the layer shift is measured using the capacitance ratio, not the capacitance itself. As a result, it is possible to obtain a multilayer circuit board and a layer displacement measurement system that can realize layer displacement measurement independent of the dielectric constant of the substrate.

  In Embodiment 1 described above, the method of calculating the shift amount is described assuming that the capacitance ratio is equal to the area ratio, but the present invention is not limited to such a method. Needless to say, this method can be realized by a method in which the relationship between the capacity ratio and the deviation amount is created in advance as a database as deviation amount specifying data by electromagnetic field simulation and actual measurement, and the deviation amount is determined by comparing with the measured capacitance ratio. Yes. In this case, since the database including the error factors such as the fringe capacity of the conductor pattern is created, it is possible to increase the accuracy of the deviation measurement.

  In the first embodiment described above, the method for determining only the deviation amount in a specific direction of the substrate (that is, the deviation amount in the direction orthogonal to the slit direction) has been described. It is not limited to. If one multilayer circuit board is provided with two or more patterns shown in FIG. 1 in different directions, a deviation amount in another direction can also be determined. That is, by measuring the amount of deviation in two directions, it is possible to completely determine in which direction and how much the deviation has occurred on the plane.

Embodiment 2. FIG.
In the first embodiment, the case where the deviation amount is measured by the deviation amount detector 4a based on the capacity measurement function has been described. In contrast, in the second embodiment, a case will be described in which a shift amount detector 4b that measures a shift amount based on the resonance frequency measurement function is used instead of the shift amount detector 4a.

  FIG. 6 is a schematic diagram of a layer displacement measurement system applied to the multilayer circuit board according to Embodiment 2 of the present invention. Compared with the configuration of FIG. 5 in the first embodiment, FIG. 6 in the second embodiment has a configuration in which an inductor 5 is added in series between the conductor pattern 1 and the deviation amount detector 4b. The inductor 5 may be realized as a conductor pattern on the multilayer circuit board or may be added externally.

  Next, a specific operation of the layer displacement measuring system shown in FIG. 6 in Embodiment 2 of the present invention will be described. Although the operation is almost the same as in the first embodiment, the deviation amount detector 4b measures the capacitance between the conductor patterns 1 and 2a, the resonance frequency by the inductor 5, and the capacitance between the conductor patterns 1 and 2b. The resonance frequency by the inductor 5 is obtained. When the layer shift occurs, the capacity changes as described in the first embodiment.

  The resonance frequency of the series connection of the capacitor and the inductor is proportional to the reciprocal of the square root of the capacitor. Therefore, the change in capacitance is reflected in the resonance frequency. Here, when the ratio of the two resonance frequencies is taken, the influence of the dielectric constant and the inductor shared by the two resonance circuits is canceled, and the resonance frequency ratio becomes a value that does not depend on the dielectric constant of the substrate. Since the reciprocal of the square of the resonance frequency ratio is the capacitance ratio, if the capacitance value is proportional to the opposing area, the calculation of the layer shift amount can be realized as in the first embodiment.

  As described above, according to the second embodiment, the layer shift is measured using the resonance frequency ratio instead of the resonance frequency itself. As a result, it is possible to obtain a multilayer circuit board and a layer displacement measurement system that can realize layer displacement measurement independent of the dielectric constant of the substrate and the inductor.

  In the second embodiment described above, the method of calculating the shift amount is described assuming that the reciprocal of the square of the resonance frequency ratio is equal to the area ratio. However, the present invention is not limited to such a method. . It is also possible to create a database of the relationship between the resonance frequency ratio and the deviation amount as deviation amount identification data in advance by electromagnetic field simulation or actual measurement, and to determine the deviation amount by comparing it with the measured resonance frequency ratio. Needless to say. In this case, since the database including the error factors such as the fringe capacity of the conductor pattern is created, it is possible to increase the accuracy of the deviation measurement.

  Further, in the above-described second embodiment, the method of determining only the shift amount in a specific direction of the substrate (that is, the shift amount in the direction orthogonal to the direction of the slit) has been described. It is not limited to. If one multilayer circuit board is provided with two or more patterns shown in FIG. 1 in different directions, a deviation amount in another direction can also be determined. That is, by measuring the amount of deviation in two directions, it is possible to completely determine in which direction and how much the deviation has occurred on the plane.

Embodiment 3 FIG.
In the third embodiment, a case where a deviation amount including a rotational deviation is measured will be described. FIG. 7 is a top view of conductor patterns provided on specific first and second layers of the multilayer circuit board according to Embodiment 3 of the present invention. FIG. 8 is a top view when a layer shift occurs in the multilayer circuit board according to Embodiment 3 of the present invention. FIG. 8 illustrates a state in which the conductor pattern 1 is shifted leftward and counterclockwise in the drawing with respect to the conductor patterns 2a to 2d.

  The multilayer circuit board according to the third embodiment includes a conductor pattern 1 provided on the first layer, conductor patterns 2a to 2d provided on the second layer, and slits 3a and 3b. The conductor pattern 1 is a conductor pattern provided in a certain layer (corresponding to a specific first layer) of the multilayer circuit board, and the conductor patterns 2a to 2d are layers different from the conductor pattern 1 (specific second layer). The conductor pattern is divided into four by the slits 3a and 3b.

  The size of the conductor pattern 1 in the first embodiment is smaller than the combined size of the conductor patterns 2a, 2b, 2c, and 2d. Even when a layer shift occurs between the first layer and the second layer, when viewed as a top view, the conductor pattern 1 does not protrude from the conductor patterns 2a, 2b, 2c, and 2d. Designed.

  In addition, the slits 3a and 3b have an intersection at the lower part of the conductor pattern 1 so that the intersection does not protrude from the conductor pattern 1 even when a layer shift occurs between the first layer and the second layer. Designed.

  With the above configuration, four capacitors are formed between the conductor pattern 1 and the conductor patterns 2a, 2b, 2c, and 2d using the conductor pattern 1 as a common electrode. Then, by using a circuit similar to the deviation amount detector 4a shown in FIG. 5, the capacitances of the four capacitors are measured, the ratios thereof are calculated, and converted into deviation amounts.

  Next, a specific operation of the layer displacement measurement system shown in FIG. 5 in Embodiment 3 of the present invention will be described. When a layer shift including a rotation shift occurs, the positions of the slits 3a and 3b are displaced from the state shown in FIG. 7 as shown in FIG. Thereby, each area which the conductor pattern 1 and the conductor patterns 2a, 2b, 2c, and 2d oppose changes. As a result, the measured capacitance value also changes corresponding to the area change.

  Here, the capacitance between the conductor patterns 1 and 2a, the capacitance between the conductor patterns 1 and 2b, the capacitance between the conductor patterns 1 and 2c, and the capacitance between the conductor patterns 1 and 2d are all proportional to the dielectric constant of the substrate. Yes.

  Therefore, if one of the four measured capacitance values is used as a reference and the ratio to the remaining three capacitance values is taken, the influence of the dielectric constant is canceled, and the three capacitance ratios are related to the dielectric constant of the substrate. It can be an independent value.

  If the capacitance value is proportional to the opposing area, the capacitance ratio and the area ratio are equal. Since there are three parameters for the layer shift including the rotation shift: the shift amount in the x direction, the shift amount in the y direction, and the angle of the rotation shift, the positions of the slits 3a and 3b with respect to the conductor pattern 1 using the above three capacitance ratios. However, it can be geometrically determined such that there is a slit at a position where the area of the conductor pattern 1 is divided into the same ratio as the capacitance ratio. Thereby, the positional relationship between the specific first layer and the second layer of the multilayer circuit board can be determined. That is, in FIG. 8, the amount of layer displacement including rotational displacement can be determined from the ratio of the area of the conductor pattern 1 to each of the conductor patterns 2a to 2d divided by the slits 3a and 3b.

  As described above, according to the third embodiment, the layer shift is measured using a value obtained by converting four capacitance values into three capacitance ratios, not the capacitance itself. As a result, as in the first embodiment, it is possible to obtain a multilayer circuit board and a layer displacement measurement system that can realize layer displacement measurement including rotation displacement without depending on the dielectric constant of the substrate.

  In Embodiment 3 described above, the method of calculating the shift amount is described assuming that the capacitance ratio is equal to the area ratio, but the present invention is not limited to such a method. Needless to say, this method can be realized by a method in which the relationship between the capacity ratio and the deviation amount is created in advance as a database as deviation amount specifying data by electromagnetic field simulation and actual measurement, and the deviation amount is determined by comparing with the measured capacitance ratio. Yes. In this case, since the database including the error factors such as the fringe capacity of the conductor pattern is created, it is possible to increase the accuracy of the deviation measurement.

  Further, in the above-described third embodiment, the method by capacitance measurement similar to that in the first embodiment has been described. However, as in the second embodiment, it can also be realized by a method by resonance frequency measurement. Needless to say.

  DESCRIPTION OF SYMBOLS 1 Conductor pattern (1st conductor pattern), 2a, 2b Conductor pattern (2nd conductor pattern), 3a, 3b Slit, 4a, 4b Deviation amount detector, 5 Inductor.

Claims (9)

A first conductor pattern provided on a specific first layer of a multilayer structure;
A multilayer circuit board comprising: a second conductor pattern provided on a specific second layer different from the first layer of the multilayer structure;
The first conductor pattern is disposed opposite to the second conductor pattern, has a smaller area than the second conductor pattern, and has a maximum positional shift in the stack of the first layer and the second layer. Even in this case, it is designed not to protrude from the second conductor pattern,
The second conductor pattern is divided into a plurality of conductor patterns by slits,
Each of the first conductor pattern and the plurality of divided conductor patterns is provided with a terminal for measuring a capacitance between the conductor patterns ,
The multilayer circuit board, wherein the second conductor pattern is divided into two by one slit . A first conductor pattern provided on a specific first layer of a multilayer structure;
A multilayer circuit board comprising: a second conductor pattern provided on a specific second layer different from the first layer of the multilayer structure;
The first conductor pattern is disposed opposite to the second conductor pattern, has a smaller area than the second conductor pattern, and has a maximum positional shift in the stack of the first layer and the second layer. Even in this case, it is designed not to protrude from the second conductor pattern,
The second conductor pattern is divided into a plurality of conductor patterns by slits,
Each of the first conductor pattern and the plurality of divided conductor patterns is provided with a terminal for measuring a capacitance between the conductor patterns ,
2. A multilayer circuit board , wherein two or more sets of deviation measurement patterns each including the first conductor pattern and the second conductor pattern are provided with different slit directions . The multilayer circuit board according to claim 1 ,
A multilayer circuit board, wherein two or more sets of deviation measurement patterns each including the first conductor pattern and the second conductor pattern are provided with different slit directions. A first conductor pattern provided on a specific first layer of a multilayer structure;
A multilayer circuit board comprising: a second conductor pattern provided on a specific second layer different from the first layer of the multilayer structure;
The first conductor pattern is disposed opposite to the second conductor pattern, has a smaller area than the second conductor pattern, and has a maximum positional shift in the stack of the first layer and the second layer. Even in this case, it is designed not to protrude from the second conductor pattern,
The second conductor pattern is divided into a plurality of conductor patterns by slits,
Each of the first conductor pattern and the plurality of divided conductor patterns is provided with a terminal for measuring a capacitance between the conductor patterns ,
The second conductor pattern is divided into four by the two slits having an intersection at the lower part of the first conductor pattern, and the intersection is a maximum position in the stack of the first layer and the second layer. A multilayer circuit board, which is designed not to protrude from the first conductor pattern even when a deviation occurs . The multilayer circuit board according to any one of claims 1 to 4,
The multilayer circuit board according to claim 1, further comprising: an inductor provided as a conductor pattern between the first conductor pattern and a terminal provided in the first conductor pattern in the first layer. The multilayer circuit board according to any one of claims 1 to 4,
A multilayer circuit board comprising a configuration in which an inductor can be externally attached to a terminal provided in the first conductor pattern. A multilayer circuit board according to any one of claims 1 to 4,
Connected to the terminals provided in the first conductor pattern of the multilayer circuit board and the respective terminals provided in the plurality of divided conductor patterns, the first conductor pattern and the plurality of conductor patterns Each capacitance value between the first layer and the second layer is measured using a value that does not depend on the dielectric constant of the substrate, which is converted into a ratio with the other capacitance value based on one measured capacitance value. A layer displacement measuring system comprising: a displacement amount detector for calculating a displacement amount due to stacking. A multilayer circuit board according to claim 5 or 6,
The first conductor pattern and the plurality of conductors are connected to the first conductor pattern of the multilayer circuit board via the inductor, and are connected to respective terminals provided in the divided conductor patterns. The first layer and the first layer are measured using a value that does not depend on the dielectric constant of the substrate , measured for each resonance frequency between the patterns and converted into a ratio to the other resonance frequency based on the measured one resonance frequency. A layer displacement measuring system comprising: a displacement amount detector that calculates a displacement amount due to the lamination of two layers. The layer displacement measuring system according to claim 7 or 8,
The deviation amount detector includes a storage unit in which deviation amount specifying data defining a relationship between the calculated ratio and the deviation amount is stored in advance, and a deviation corresponding to the ratio is based on the deviation amount specifying data. A layer displacement measurement system characterized by calculating a quantity.

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