JP6965110B2 - Inspection equipment and inspection method - Google Patents

Description

The present invention relates to an inspection device and an inspection method for inspecting a connection state between a plurality of conductors connected to each other.

As an inspection device of this type, a circuit board inspection device disclosed by the applicant in Patent Document 1 below is known. This circuit board inspection device is configured to include a measuring unit, a storage unit, and a control unit, and the measuring unit includes wiring patterns formed on the circuit board and vias connecting the wiring patterns (hereinafter, wiring patterns and vias). The resistance value of the conductor) is measured, and the control unit inspects the continuity state of the conductor by comparing the resistance value measured by the measuring unit with the quality judgment reference value stored in the storage unit. .. In this case, the reference value for quality determination is set for each conductor by adding an allowable value to the measured resistance value of the conductor in a non-defective circuit board or the resistance value of the conductor specified by using design data or the like.

Japanese Unexamined Patent Publication No. 2009-288115 (Page 5-7, Fig. 1-2)

However, the circuit board inspection device described above has the following problems to be improved. Specifically, in this circuit board inspection device, a passability judgment is set for each conductor by adding an allowable value to the resistance value of the conductor specified by using the measured value of the resistance value of the conductor in a non-defective circuit board or design data. Inspection is performed using the standard value. Therefore, when inspecting a circuit board on which a large number of conductors are formed by using this circuit board inspection device, it takes a lot of labor and time to set a reference value for quality determination. In addition, since the permissible value to be added to the resistance value when setting the pass / fail judgment reference value is also determined based on the experience value, skill is required to set the pass / fail judgment reference value that enables accurate inspection. You will need it. Therefore, in this circuit board inspection device, it is difficult to improve the inspection efficiency because it is difficult to efficiently set the quality determination reference value.

Further, when the connection between the conductors is insufficient, the resistance value may differ due to the difference in the current value of the inspection signal supplied at the time of inspection. Specifically, in such a conductor, the resistance value measured by supplying an inspection signal having a large current value may be smaller than the resistance value measured by supplying an inspection signal having a small current value. .. Originally, such a conductor must be determined as a current value-dependent defect, but since the above-mentioned circuit board inspection device is not provided with a means for determining a current value-dependent defect, such a defect is determined. It is difficult to judge correctly. Further, in this type of substrate, a semiconductor is formed by a component contained in a material used for connecting conductors (wiring pattern and via) and a metal constituting the wiring pattern and via, and the semiconductor and the metal rectify the semiconductor. A working shotkey connection may be formed at the connection between conductors. Since such a conductor has a different resistance value due to a difference in the polarity of the inspection signal supplied at the time of inspection, it must be originally determined as a polarity dependence defect, but in the above circuit board inspection apparatus, it must be determined. Since there is no means for determining the polarity dependence defect, it is difficult to correctly determine such a defect.

The present invention has been made in view of such a problem, and an object of the present invention is to provide an inspection device and an inspection method capable of efficiently and accurately determining a connected state of a conductor.

In order to achieve the above object, the inspection apparatus according to claim 1 includes a measuring unit that measures a resistance value between the conductors in a state where inspection signals are supplied to a plurality of conductors connected to each other, and the measuring unit. An inspection device including an inspection unit that inspects the connection state between the conductors based on the resistance value measured by the first conductor, and the current value is defined as the first current value and the upper limit value of the voltage value is the first. The first inspection signal as the inspection signal defined in the voltage value is switched between the first polarity and the second polarity in which the first polarity is inverted and output, and the current value is higher than the first current value. The second inspection signal as the inspection signal defined by the second voltage value whose upper limit value of the voltage value defined by the large second current value is larger than the first voltage value is the first polarity and the first polarity. A signal output unit capable of switching and outputting with two polarities and a control unit for controlling the signal output unit are provided, and the control unit controls the signal output unit to output the first inspection signal to the first. A first state in which one of the one polarity and the second polarity is output and supplied to the respective conductors, and the other polarity of the first polarity and the second polarity of the first inspection signal. A second state in which the second state is output and supplied to the respective conductors, and a second state in which the second inspection signal is output in one of the first polarity and the second polarity and supplied to the respective conductors. A switching process for switching between the third state and the fourth state in which the second inspection signal is output in the other polarity of the first polarity and the second polarity and supplied to the respective conductors is executed, and the above-mentioned The inspection unit has a first resistance value as the resistance value measured by the measuring unit in the first state, and a second resistance as the resistance value measured by the measuring unit in the second state. A value , a third resistance value as the resistance value measured by the measuring unit in the third state , and a fourth resistance value as the resistance value measured by the measuring unit in the fourth state. When the mutual relationship between the two conductors satisfies a predetermined condition and all of the resistance values are less than the values indicating the insulation state, the connection state between the conductors is judged to be good, and the first to fourth resistances are said to be good. Judgment that the connection state between the conductors is judged to be defective when the mutual relationship between the values does not satisfy the above condition and at least one of the resistance values is at least one of the values indicating the insulation state. Execute the process.

Further, the inspection device according to claim 2 is the inspection device according to claim 1, wherein the inspection unit has all the ratios of the first to fourth resistance values within a predetermined reference range. The determination process is executed with the above condition as the condition.

The inspection device according to claim 3 is the inspection device according to claim 1 or 2, wherein the control unit has the first state, the second state, and the third state in the switching process. And the fourth state is switched in this order.

Further, the inspection device according to claim 4 is the inspection device according to claim 3, wherein the inspection unit has the first resistance value less than the value indicating the insulation state and the second resistance value is the insulation state. When the value indicating the insulation state or more, or when the second resistance value is less than the value indicating the insulation state and the first resistance value is greater than or equal to the value indicating the insulation state, the conductors are connected to each other. Is determined to be a polarity-dependent defect in which the resistance value differs depending on the polarity.

Further, the inspection device according to claim 5 is the inspection device according to claim 3 or 4, wherein the inspection unit has a ratio of the first resistance value to the second resistance value within the reference range. When the ratio of the first resistance value to the third resistance value or the ratio of the second resistance value to the third resistance value is out of the reference range, the connection state between the conductors is reached. Is determined to be a current value dependence defect in which the resistance value differs depending on the difference in the current value.

Further, in the inspection method according to claim 6, the resistance value between the conductors is measured in a state where the inspection signal is supplied to a plurality of conductors connected to each other, and each of the above-mentioned inspection methods is based on the measured resistance value. An inspection method for inspecting the connection state between conductors, the first inspection signal as the inspection signal in which the current value is defined by the first current value and the upper limit of the voltage value is defined by the first voltage value. Is output in one of the first polarity and the second polarity in which the first polarity is inverted and supplied to the respective conductors, and the first inspection signal is transmitted to the first polarity and the first polarity. The second state in which the conductor is output with the other polarity of the second polarity and supplied to each conductor, and the second current value whose current value is larger than the first current value are defined, and the upper limit of the voltage value is the first. A second inspection signal as the inspection signal defined by a second voltage value larger than the first voltage value is output to each of the conductors with either the first polarity or the second polarity. A switching process is executed to switch between the third state to be supplied and the fourth state in which the second inspection signal is output with the other polarity of the first polarity and the second polarity and supplied to each conductor. and, said first resistance value as the resistance value measured in the first state, the second resistance value as the resistance value measured in the second state, said measured by the third-state resistance third resistance value as the value, and all insulation state of the fourth resistance value of the mutual relationship predetermined condition satisfied and the resistance value as the resistance value measured in the fourth state When the value is less than the indicated value, the connection state between the conductors is judged to be good, and when the mutual relationship between the first to fourth resistance values does not satisfy the above conditions and one or more of the resistance values is the above. When at least one of the values indicating the insulation state or more, the determination process for determining the connection state between the conductors as defective is executed.

In the inspection device according to claim 1 and the inspection method according to claim 6, the mutual relationship between the resistance values of the conductors measured in each of the first to fourth states satisfies a predetermined condition and each of them. When all of the resistance values are less than the values indicating the insulation state, the connection state between the conductors is judged to be good, and when the mutual relationship of the resistance values does not satisfy the conditions and one or more of the resistance values are in the insulation state. When it is at least one of the values indicating the value or more, the determination process of determining the connection state between the conductors as defective is executed. Therefore, according to this inspection device and the inspection method, it is possible to judge the quality of the connection state between the conductors without using the reference value for quality judgment for each conductor for determining the quality of the connection state between the conductors. Can be done. Therefore, according to this inspection device and inspection method, it is possible to save a lot of labor and time required for setting the quality judgment reference value for each conductor, so that the inspection efficiency can be sufficiently improved. .. In addition, according to this inspection device and inspection method, since the quality judgment reference value defined based on the experience value is not used, it is necessary to surely prevent the inspection accuracy from being lowered when the quality judgment reference value is not appropriate. As a result, the accuracy can be sufficiently improved.

Further, according to the inspection apparatus according to claim 2, each ratio is calculated by executing the determination process on the condition that all the mutual ratios of the resistance values are within the reference range, and each ratio and the reference. It is possible to reliably and highly accurately determine the quality of the connection state between conductors by a simple process of comparing with the range.

Further, in the inspection device according to claim 3, in the switching process, the first to fourth states are switched in this order. In this case, for example, a configuration in which switching to the third and fourth states is executed before switching to the first and second states, that is, inspection of a small current value after supplying a signal for inspection of a large current value is performed. It is also possible to adopt a configuration for supplying a signal. However, in this configuration, when a large current value inspection signal is supplied, the resistance value of each conductor is maintained in a small state for a while (that is, each resistance value becomes a small value), and each conductor is connected to each other. Even if the connection state is poorly dependent on the current value, it may be erroneously determined that the connection state is good. On the other hand, according to this inspection device, by switching the first to fourth states in this order, such an erroneous determination can be prevented and the current value dependence defect can be correctly determined.

Further, in the inspection device according to claim 4, when the first resistance value is less than the value indicating the insulation state and the second resistance value is equal to or more than the value indicating the insulation state, and the second resistance value indicates the insulation state. When the value is less than the value and the first resistance value is equal to or greater than the value indicating the insulation state, the connection state between the conductors is determined to be a polarity dependence defect in which the resistance value differs depending on the polarity. Therefore, according to this inspection device, the polarity dependence is performed using a general insulation resistance value measured when each conductor is in an insulated state, without using a reference value for determining the quality of the connected state. Defects can be reliably determined.

Further, in the inspection device according to claim 5, the ratio of the first resistance value to the second resistance value is within the reference range, and the ratio of the first resistance value to the third resistance value or the second resistance value. When the ratio of the resistance value to the third resistance value is out of the reference range, the connection state between the conductors is determined to be a current value dependence defect in which the resistance value differs depending on the difference in the current value. Therefore, according to this inspection device, it is possible to reliably determine the current value dependence defect based on the ratio and the reference range without using the reference value for determining the quality of the connection state.

It is a block diagram which shows the structure of the substrate inspection apparatus 1. It is a block diagram which shows the structure of the substrate 100. It is a flowchart of inspection process 50. It is a flowchart of inspection process 70. It is a block diagram which shows the structure of the multilayer board 200.

Hereinafter, embodiments of the inspection device and the inspection method will be described with reference to the attached drawings.

First, the configuration of the substrate inspection device 1 shown in FIG. 1 will be described. The substrate inspection device 1 is an example of an inspection device, and is configured to be capable of inspecting the substrate 100 shown in FIG. 2, for example.

Here, as shown in FIG. 2, the substrate 100 has conductor patterns 102a formed on the substrate main body 101, one surface 101a (upper surface in the same figure) and the other surface 101b (lower surface in the same figure) of the substrate main body 101, respectively. It is configured to include 102b (hereinafter, also referred to as “conductor pattern 102” when not distinguished) and via 103 that electrically connects the conductor patterns 102a and 102b. The substrate 100 includes a plurality of conductor patterns and vias in addition to the conductor patterns 102a and 102b and vias 103 shown in the figure. However, in order to facilitate understanding of the invention, the conductor patterns 102a and 102b and vias are provided. Illustrations other than 103 will be omitted.

On the other hand, as shown in FIG. 1, the substrate inspection device 1 includes probing mechanisms 2a and 2b (hereinafter, also referred to as “probing mechanism 2” when not distinguished), signal output unit 3, measurement unit 4, storage unit 5, and display unit. 6 and a processing unit 7 are provided.

As shown in FIG. 2, the probing mechanism 2a follows the control of the processing unit 7 and is held by a holding unit (not shown) in a direction parallel to one surface 101a of the substrate body 101 and in contact with and detached from the substrate 100. The probe 21a is moved in the direction of the probe 21a to bring the probe 21a into contact (probing) with the conductor pattern 102a formed on one surface 101a of the substrate main body 101. Further, the probing mechanism 2b is controlled by the processing unit 7, and as shown in the figure, the probing mechanism 2b is held by a holding unit (not shown) in a direction parallel to the other surface 101b of the substrate body 101 and with respect to the substrate 100. The probe 21b is moved in the direction of contact and separation, and the probe 21b is brought into contact (probing) with the conductor pattern 102b formed on the other surface 101b of the substrate main body 101.

The signal output unit 3 is configured to be able to output an inspection signal used in the inspection process 50 (see FIG. 3), which will be described later, executed by the processing unit 7 under the control of the processing unit 7. In this case, in the signal output unit 3, the current value is defined by the current value I1 (corresponding to the first current value, 5 mA as an example), and the upper limit of the voltage value is the voltage value V1 (the first voltage value). Correspondingly, as an example, the inspection signal S1 (corresponding to the first inspection signal) defined in 20 mV) is set to the first polarity (for example, the probe 21a side shown in FIG. 2 is positive (+), and the probe. A polarity with the 21b side as negative (-)) and a second polarity with the first polarity reversed (the polarity with the probe 21a side shown in the figure as negative (-) and the probe 21b side as positive (+)). It is configured so that it can be switched and output. Further, the signal output unit 3 is defined by a current value I2 (corresponding to the second current value, 100 mA as an example) whose current value is larger than the current value I1, and the upper limit of the voltage value is higher than the voltage value V1. When the inspection signal S2 (corresponding to the second inspection signal and corresponding to the second inspection signal and the inspection signals S1 and S2 are not distinguished) specified in the large voltage value V2 (corresponding to the second voltage value and, for example, 10V), "inspection" The signal S) can be switched between the above-mentioned first polarity and the second polarity for output.

According to the control of the processing unit 7, the measuring unit 4 supplies the inspection signal S output from the signal output unit 3 to the conductor patterns 102 and vias 103 via the probes 21a and 21b, and the conductor patterns 102. And the resistance value between the vias 103 is measured. The inspection signal S1 is output from the signal output unit 3 in the first polarity (an example of either the first polarity or the second polarity) and supplied to each conductor pattern 102 and via 103 (first). The resistance value measured by the measuring unit 4 in (corresponding to the state of) is also referred to as the resistance value R1 (corresponding to the first resistance value), and the inspection signal S1 has the second polarity (first polarity and second polarity). In the other example), the resistance value measured by the measuring unit 4 in the state of being output from the signal output unit 3 and being supplied to each conductor pattern 102 and the via 103 (corresponding to the second state) is set to the resistance value R2 (corresponding to the second state). It is also called (corresponding to the second resistance value). Further, the inspection signal S2 is output from the signal output unit 3 in the first polarity (an example of either the first polarity or the second polarity) and supplied to each conductor pattern 102 and via 103 (third). The resistance value measured by the measuring unit 4 in (corresponding to the state of) is also referred to as the resistance value R3 (corresponding to the third resistance value), and the inspection signal S2 has the second polarity (first polarity and second polarity). In the other example), the resistance value measured by the measuring unit 4 in the state of being output from the signal output unit 3 and being supplied to each conductor pattern 102 and the via 103 (corresponding to the fourth state) is set to the resistance value R4 (corresponding to the fourth state). It is also called (corresponding to the fourth resistance value). Further, when the resistance values R1 to R4 are not distinguished, it is also referred to as "resistance value R".

The storage unit 5 stores the substrate data Ds and the determination data Dj used in the inspection process 50. In this case, the substrate data Ds includes data indicating a position (probing position) for probing the probe 21 on the conductor pattern 102 of the substrate 100. Further, the determination data Dj includes data indicating the reference range A and the insulation resistance value Ri used when determining the quality of the connection state between the conductor pattern 102 and the via 103 in the inspection process 50. Further, the storage unit 5 stores the resistance values R1 to R4 measured by the measurement unit 4.

The display unit 6 displays various information according to the control of the processing unit 7.

The processing unit 7 functions as a control unit and controls each unit constituting the substrate inspection device 1. Further, the processing unit 7 functions as an inspection unit, executes the inspection process 50 according to a predetermined inspection method, determines the connection state between the conductor pattern 102 and the via 103 on the substrate 100, and based on the determination result. The quality of the substrate 100 is inspected.

Next, an inspection method for inspecting the substrate 100 shown in FIG. 2, for example, using the substrate inspection apparatus 1 will be described with reference to the drawings.

First, the substrate 100 is held by the holding portion (not shown), and then the operating portion (not shown) is operated to instruct the start of the inspection. In response to this, the processing unit 7 executes the inspection process 50 shown in FIG. In the inspection process 50, the processing unit 7 reads out the substrate data Ds and the determination data Dj about the substrate 100 from the storage unit 5 (step 51).

Subsequently, the processing unit 7 specifies the probing positions defined on the conductor patterns 102a and 102b formed on one surface 101a and the other surface 101b of the substrate body 101 on the substrate 100 based on the substrate data Ds. (Step 52).

Next, the processing unit 7 controls the probing mechanisms 2a and 2b to move the probes 21a and 21b, and probing the probes 21a and 21b to the probing positions of the conductor patterns 102a and 102b, respectively (step 53).

Subsequently, the processing unit 7 executes step 54. In this step 54, the processing unit 7 switches to the first state. Specifically, the processing unit 7 controls the signal output unit 3 to set the inspection signal S1 to the first polarity (the probe 21a side shown in FIG. 2 is positive (+) and the probe 21b side is negative (-)). Output with the polarity). At this time, the inspection signal S1 is supplied to each conductor pattern 102 and via 103 via the probes 21a and 21b. Further, the signal output unit 3 maintains the current value at the current value I1 and controls the output of the inspection signal S1 so that the voltage value becomes the voltage value V1 or less.

Next, the processing unit 7 controls the measuring unit 4 to measure the resistance value R1 between each conductor pattern 102 and the via 103 in the first state. In this case, the measuring unit 4 measures the resistance value R1 based on the current value (current value I1) of the inspection signal S1 supplied from the signal output unit 3 and the voltage value between the probes 21a and 21b. Further, the processing unit 7 stores the measured resistance value R1 in the storage unit 5.

Subsequently, the processing unit 7 executes step 55. In this step 55, the processing unit 7 switches to the second state. Specifically, the processing unit 7 controls the signal output unit 3 to output the inspection signal S1 with the second polarity (the polarity in which the first polarity is inverted), and the inspection signal is output to each conductor pattern 102 and via 103. S1 is supplied. At this time, the signal output unit 3 maintains the current value at the current value I1 and controls the output of the inspection signal S1 so that the voltage value becomes the voltage value V1 or less. Next, the processing unit 7 controls the measuring unit 4 to measure the resistance value R2 between each conductor pattern 102 and the via 103 in the second state, and stores the measured resistance value R2 in the storage unit 5.

Subsequently, the processing unit 7 executes step 56. In this step 56, the processing unit 7 switches to the third state. Specifically, the processing unit 7 controls the signal output unit 3 to output the inspection signal S2 with the first polarity, and supplies the inspection signal S2 to each conductor pattern 102 and via 103. At this time, the signal output unit 3 maintains the current value at the current value I2 and controls the output of the inspection signal S2 so that the voltage value becomes the voltage value V2 or less. Next, the processing unit 7 controls the measuring unit 4 to measure the resistance value R3 between each conductor pattern 102 and the via 103 in the third state, and stores the measured resistance value R3 in the storage unit 5.

Subsequently, the processing unit 7 executes step 57. In this step 57, the processing unit 7 switches to the fourth state. Specifically, the processing unit 7 controls the signal output unit 3 to output the inspection signal S2 with the second polarity, and supplies the inspection signal S2 to each conductor pattern 102 and via 103. At this time, the signal output unit 3 maintains the current value at the current value I2 and controls the output of the inspection signal S2 so that the voltage value becomes the voltage value V2 or less. Next, the processing unit 7 controls the measuring unit 4 to measure the resistance value R4 between each conductor pattern 102 and the via 103 in the fourth state, and stores the measured resistance value R4 in the storage unit 5. The switching to each state performed in steps 54 to 57 described above corresponds to the switching process.

Subsequently, the processing unit 7 executes a determination process for determining the quality of the connection state between the conductor pattern 102 and the via 103 (step 58). In this determination process, the processing unit 7 first reads the resistance values R1 to R4 from the storage unit 5. Next, the processing unit 7 calculates the mutual ratio p1 to p4 of each resistance value R1 to R4 (for example, p1 = R1 / R2, p2 = R2 / R3, p3 = R3 / R4, p4 = R4 / R1). do. Subsequently, the processing unit 7 satisfies the condition that all of the ratios p1 to p4 are within the predetermined reference range A (for example, the range of 0.8 to 1.2), and each resistance value R1 to R1. It is determined whether or not all of R4 are less than the insulation resistance value Ri (for example, 100 MΩ) indicating the insulation state.

Here, for example, when the conductor pattern 102 and the via 103 are in an insulated state (when the conductor pattern 102 and the via 103 are separated from each other), the resistance values R1 to R4 are equal to or higher than the insulating resistance value Ri. Therefore, when one or more of the resistance values R1 to R4 are equal to or higher than the insulation resistance value Ri, the processing unit 7 determines that the connection state between the conductor pattern 102 and the via 103 is poor (conduction failure).

On the other hand, in this type of substrate 100, although the conductor pattern 102 and the via 103 are connected, the conductor pattern 102 and the via 103 are composed of the components contained in the material used when connecting the conductor pattern 102 and the via 103. A semiconductor may be formed by the metal to be formed, and a shotkey connection exhibiting a rectifying action may be formed at the connection portion between the conductor pattern 102 and the via 103 by the semiconductor and the metal. In such a conductor pattern 102 and the via 103, the resistance value may differ (there is a polarity dependence) due to the difference in the polarity of the inspection signal S. Specifically, in such a conductor pattern 102 and via 103, for example, when the inspection signal S1 is supplied with the first polarity, the resistance value R1 is an appropriate value and the inspection signal S1 is supplied with the second polarity. Occasionally, the resistance value R2 becomes equal to or higher than the insulation resistance value Ri, and the ratio p1 (p1 = R1 / R2) of the resistance value R1 and the resistance value R2 may be outside the reference range A. On the contrary, when the inspection signal S1 is supplied with the first polarity, the resistance value R1 is equal to or higher than the insulation resistance value Ri, and when the inspection signal S1 is supplied with the second polarity, the resistance value R2 is appropriate. The value may be such that the ratio p1 may be outside the reference range A. Further, for example, when the inspection signal S2 is supplied with the first polarity, the resistance value R3 is an appropriate value, and when the inspection signal S2 is supplied with the second polarity, the resistance value R4 becomes the insulation resistance value Ri or more, and the resistance. The ratio p3 (p3 = R3 / R4) of the value R3 and the resistance value R4 may be outside the reference range A. Further, conversely, when the inspection signal S2 is supplied with the first polarity, the resistance value R3 is equal to or higher than the insulation resistance value Ri, and when the inspection signal S2 is supplied with the second polarity, the resistance value R4 is appropriate. The value may be such that the ratio p3 may be outside the reference range A. Therefore, when the ratio p1 or the ratio p3 is outside the reference range A, the processing unit 7 determines that the connection state between the conductor pattern 102 and the via 103 is defective (polarity dependence defect).

Further, when the conductor pattern 102 and the via 103 are connected but the connection is insufficient, specifically, the conductor pattern 102 and the via 103 are connected in a pointed manner, and the area of the connecting portion is small. Occasionally, the resistance value may differ (there is a current value dependence) due to the difference in the current value of the inspection signal S supplied to the conductor pattern 102 and the via 103. Specifically, when the connection between the conductor pattern 102 and the via 103 is insufficient, the resistance values R3 and R4 when the inspection signal S2 having a large current value is supplied are the inspection signals having a small current value. It becomes smaller than the resistance values R1 and R2 when S1 is supplied, and the ratio p2 (p2 = R2 / R3) between the resistance value R2 and the resistance value R3 and the ratio p4 (p4 = R4) between the resistance value R4 and the resistance value R1. / R1) may be outside the reference range A. Therefore, when the ratio p2 or the ratio p4 is outside the reference range A, the processing unit 7 determines that the connection state between the conductor pattern 102 and the via 103 is defective (current value dependence defect).

In this case, for example, a configuration and method for performing switching to the third state or the fourth state before switching to the first state or the second state, that is, the inspection signal S2 having a large current value. In the configuration and method of supplying the inspection signal S1 having a small current value after the supply, the connection state between the conductor pattern 102 and the via 103 is improved when the inspection signal S2 is supplied, and the conductor pattern 102 and the via 103 are supplied. The resistance value may remain low for some time. At this time, the resistance values R1 to R4 are all small values, and even if the connection state between the conductor pattern 102 and the via 103 has poor current value dependence, it is erroneously determined that the connection state is good (considered to be good). There is a risk. On the other hand, in the substrate inspection device 1, by switching the first to fourth states in this order, it is possible to prevent such an erroneous determination and correctly determine the current value dependence defect. It has become. In the substrate inspection device 1, the current value I1 of the inspection signal S1 is defined as a value small enough to prevent the improvement of the connection state between the conductor pattern 102 and the via 103 (5 mA in this example). ing.

On the other hand, with respect to the conductor pattern 102 and the via 103, when the above-mentioned various defects (conductivity defect, polarity dependence defect and current value dependence defect) do not exist, all of the mutual ratios p1 to p4 of the resistance values R1 to R4 are all. Within the reference range A (satisfying predetermined conditions), all of the resistance values R1 to R4 are less than the insulation resistance value Ri. Therefore, when all of the ratios p1 to p4 are within the reference range A and all of the resistance values R1 to R4 are less than the insulation resistance value Ri, the processing unit 7 has a good connection state between the conductor pattern 102 and the via 103. Is determined.

Next, the processing unit 7 determines whether or not the determination of the quality of the connection state of all the conductor patterns 102 has been completed (step 59).

In this case, when it is determined that the determination of the quality of the connection state of all the conductor patterns 102 and the via 103 has not been completed, the processing unit 7 specifies the probing position in another conductor pattern (step 52). ), Subsequently, each of the above-mentioned processes of steps 53 to 58 is executed to determine whether or not the other conductor patterns and vias are connected.

Hereinafter, in the same manner, the processing unit 7 determines whether or not all the other conductor patterns and vias are connected.

Next, when the processing unit 7 determines in step 59 that the determination of the quality of the connection state of all the conductor patterns and vias has been completed, the processing unit 7 determines the quality of the substrate 100 based on the determination result and displays the determination result. Displayed in unit 6 (step 60). In this case, when the processing unit 7 determines that all the conductor patterns and the connection states of the vias are good, the processing unit 7 determines that the substrate 100 is good, and causes the display unit 6 to indicate that fact. When it is determined that the connection state of one or more sets of conductor patterns and vias is defective, the substrate 100 is determined to be defective, and information indicating that fact and the conductor pattern and vias for which the connection state is determined to be defective is displayed on the display unit. 6 is displayed, and the inspection process 50 is completed.

Next, a configuration and a method in which the processing unit 7 executes the inspection process 70 shown in FIG. 4 instead of the inspection process 50 described above will be described. In the inspection process 70, duplicate description will be omitted for the step of performing the same process as the step of the inspection process 50.

In this inspection process 70, unlike the inspection process 50 in which the determination process is executed after all the resistance values R1 to R4 are measured, the determination process is executed every time the resistance values R1 to R4 are measured. Specifically, as shown in FIG. 4, after switching to the first state and measuring the resistance value R1, the quality of the connection state between the conductor pattern 102 and the via 103 is determined (step). 74). At this time, for example, when the resistance value R1 is equal to or higher than the insulation resistance value Ri and the connection state between the conductor pattern 102 and the via 103 is determined to be defective (conduction defect) (step 75), the processing unit 7 is subjected to the first step. Step 81 similar to step 59 of the inspection process 50 is executed without switching to the second to fourth states and measuring the resistance values R2 to R4 (steps 76 to 80).

On the other hand, when the resistance value R1 is less than the insulation resistance value Ri, in step 75, the connection state between the conductor pattern 102 and the via 103 is not determined to be defective, and step 76 is executed to return to the second state. After switching and measuring the resistance value R2, the quality of the connection state is determined. At this time, for example, the resistance value R2 is equal to or higher than the insulation resistance value Ri, or the ratio p1 (p1 = R1 / R2) is outside the reference range A, and the connection state between the conductor pattern 102 and the via 103 is poor (conduction failure). When it is determined (or polarity dependence defect) (step 77), the processing unit 7 switches to the third and fourth states and executes the measurement of the resistance values R3 and R4 (steps 78 to 80). Instead, step 81 is executed.

Further, when the resistance value R2 is less than the insulation resistance value Ri and the ratio p1 is within the reference range A, in step 77, the connection state between the conductor pattern 102 and the via 103 is not determined to be defective, and step 78 is performed. After executing the switching to the third state and the measurement of the resistance value R3, the judgment of the quality of the connection state is executed. At this time, for example, the resistance value R3 is equal to or higher than the insulation resistance value Ri, or the ratio p2 (p2 = R2 / R3) is outside the reference range A, and the connection state between the conductor pattern 102 and the via 103 is poor (conduction failure). When it is determined (step 79), the processing unit 7 executes step 81 without switching to the fourth state and measuring the resistance value R4 (step 80). ..

Further, when the resistance value R3 is less than the insulation resistance value Ri and the ratio p2 is within the reference range A, in step 79, the connection state between the conductor pattern 102 and the via 103 is not determined to be defective, and step 80 is performed. After executing the switching to the fourth state and the measurement of the resistance value R4, the judgment of the quality of the connection state is executed. At this time, for example, when the resistance value R4 is equal to or higher than the insulation resistance value Ri, the ratio p3 (p3 = R3 / R4) is outside the reference range A, or the ratio p4 (p4 = R4 / R1) is outside the reference range A, The processing unit 7 determines that the connection state between the conductor pattern 102 and the via 103 is defective (conductivity failure, polarity dependence failure, or current value dependence failure). On the other hand, when the resistance value R4 is less than the insulation resistance value Ri and both the ratio p3 and the ratio p4 are within the reference range A, the processing unit 7 determines that the connection state between the conductor pattern 102 and the via 103 is good. Subsequently, the processing unit 7 executes step 81.

In the configuration and method for executing the inspection process 70, as described above, the determination process is executed every time the resistance values R1 to R4 are measured, and when it is determined that the connection state between the conductor pattern 102 and the via 103 is defective. Since switching to another state and measurement of another resistance value R can be omitted, the inspection efficiency can be sufficiently improved accordingly.

As described above, in the substrate inspection device 1 and the inspection method, the mutual relationship between the resistance values R1 to R4 of the conductor pattern 102 and the via 103 measured in each of the first to fourth states satisfies a predetermined condition. When all of the resistance values R1 to R4 are less than the insulation resistance value Ri, the connection state between the conductor pattern 102 and the via 103 is judged to be good, and when the mutual relationship between the resistance values R1 to R4 does not satisfy the conditions and the resistance. When at least one of the values R1 to R4 is at least one of the insulation resistance values Ri or more, the determination process of determining the connection state between the conductor pattern 102 and the via 103 as defective is executed. Therefore, according to the substrate inspection device 1 and the inspection method, the conductor pattern 102 for determining the quality of the connection state between the conductor pattern 102 and the via 103 and the conductor pattern 102 and the reference value for quality determination for each via 103 are not used. It is possible to determine whether the connection state between the pattern 102 and the via 103 is good or bad. Therefore, according to the substrate inspection device 1 and the inspection method, a lot of labor and time required for setting the pass / fail judgment reference value for each of the conductor pattern 102 and the via 103 can be omitted, so that the inspection efficiency can be improved. It can be improved sufficiently. Further, according to the substrate inspection device 1 and the inspection method, since the quality judgment reference value defined based on the empirical value is not used, the deterioration of the inspection accuracy when the quality judgment reference value is not appropriate is surely prevented. As a result, the accuracy can be sufficiently improved.

Further, according to the substrate inspection device 1 and the inspection method, the ratios p1 to p1 are executed by executing the determination process on the condition that all of the mutual ratios p1 to p4 of the resistance values R1 to R4 are within the reference range A. The quality of the connection state between the conductor pattern 102 and the via 103 can be reliably and highly accurately determined by a simple process of calculating p4 and comparing the ratios p1 to p4 with the reference range A.

Further, in the substrate inspection device 1 and the inspection method, the first to fourth states are switched in this order in the switching process. In this case, for example, a configuration and method in which switching to the third and fourth states is executed before switching to the first and second states, that is, a small current after supplying the inspection signal S2 having a large current value. A configuration and method for supplying the value inspection signal S1 can also be adopted. However, in this configuration and method, the resistance values of the conductor pattern 102 and the via 103 are maintained in a small state for a while when the inspection signal S2 is supplied (that is, the resistance values R1 to R4 are all small values). Even if the connection state between the conductor pattern 102 and the via 103 is poorly dependent on the current value, it may be erroneously determined that the connection state is good. On the other hand, according to the substrate inspection device 1 and the inspection method, by switching the first to fourth states in this order, such an erroneous determination is prevented and the current value dependence defect is correctly determined. can do.

Further, in the substrate inspection device 1 and the inspection method, when the resistance value R1 is less than the insulation resistance value Ri indicating the insulation state and the resistance value R2 is the insulation resistance value Ri or more, and when the resistance value R2 is less than the insulation resistance value Ri, the resistance When the value R1 is equal to or higher than the insulation resistance value Ri, the connection state of the conductor pattern 102 and the via 103 is determined to be a polarity dependence defect in which the resistance value differs depending on the polarity. Therefore, according to the substrate inspection device 1 and the inspection method, general insulation measured when the conductor pattern 102 and the via 103 are in an insulated state without using a reference value for determining the quality of the connected state. The resistance value Ri can be used to reliably determine the polarity dependence defect.

Further, in the substrate inspection device 1 and the inspection method, when the ratio p1 of the resistance value R1 and the resistance value R2 is within the reference range A and the ratio p2 of the resistance value R2 and the resistance value R3 is outside the reference range A. , The connection state of the conductor pattern 102 and the via 103 is determined to be a current value dependence defect in which the resistance value differs depending on the difference in the current value. Therefore, according to the substrate inspection device 1 and the inspection method, the current value dependence defect is ensured based on the ratios p1 and p2 and the reference range A without using the reference value for determining the quality of the connection state. Can be determined.

The substrate inspection device 1 and the inspection method are not limited to the above configurations and methods. For example, the mutual ratio of the resistance values R1 to R4 is not limited to the above-mentioned ratios p1 to p4 (p1 = R1 / R2, p2 = R2 / R3, p3 = R3 / R4, p4 = R4 / R1). Other ratios in which the combination of the two values R1 to R4 are changed can also be adopted.

Further, although the configuration and method for executing the determination process on the condition that all the mutual ratios of the resistance values R1 to R4 are within the reference range A are described above, other conditions can also be adopted. For example, a configuration and a method of executing the determination process on the condition that the mutual difference values of the resistance values R1 to R4 are within the reference range can be adopted.

Further, the above is an example of inspecting the quality of the connection state between the two conductor patterns 102a and 102b formed on one surface 101a and the other surface 101b of the substrate body 101 and the via 103 by using the substrate inspection device 1 and the inspection method. However, as shown in FIG. 5, the multilayer board 200 in which the conductor pattern 102c is formed in the inner layer 101c of the substrate body 101 and the three conductor patterns 102a, 102b, 102c are connected by the two vias 103a, 103b is inspected. Therefore, the quality of the connection state between the conductor patterns 102a, 102b, 102c and the vias 103a, 103b can be determined by using the substrate inspection device 1 and the inspection method. It is also possible to inspect a multilayer substrate in which four or more conductor patterns are connected by three or more vias.

Further, not only the quality of the connection state between the conductor pattern 102 formed on the substrate 100 or the multilayer substrate 200 and the via 103 is determined, but also the soldered portion between the terminal of the electronic component mounted on the substrate 100 and the conductor pattern 102. The substrate inspection device 1 and the inspection method can also be used to determine whether the connection state is good or bad (poor contact failure).

Further, the polarity of the inspection signal S1 in the first state and the second state described above may be opposite to the polarity described above, or the inspection signal in the third state and the fourth state described above may be used. The polarity of S2 may be opposite to the above-mentioned polarity.

1 Substrate inspection device 3 Signal output unit 4 Measuring unit 7 Processing unit 100 Substrate 102a, 102b, 102c Conductor pattern 103, 103a, 103b Via 200 Multilayer board A Reference range I1, I2 Current value R1 to R4 Resistance value Ri Insulation resistance value S1 , S2 Inspection signal V1, V2 Voltage value

Claims (6)

A measuring unit that measures the resistance value between the conductors while the inspection signal is supplied to a plurality of conductors connected to each other, and the conductors based on the resistance value measured by the measuring unit. An inspection device equipped with an inspection unit that inspects the connection status.
The first inspection signal as the inspection signal whose current value is defined by the first current value and the upper limit of the voltage value is defined by the first voltage value is the first polarity and the second polarity is inverted. The inspection is performed by switching the output according to the polarity, and the current value is defined by the second current value larger than the first current value, and the upper limit of the voltage value is defined by the second voltage value larger than the first voltage value. A signal output unit capable of switching between the first polarity and the second polarity to output a second inspection signal as a signal for use and a control unit for controlling the signal output unit are provided.
The control unit controls the signal output unit to output the first inspection signal in either the first polarity or the second polarity and supply the first inspection signal to the respective conductors. The state, the second state in which the first inspection signal is output in the other polarities of the first polarity and the second polarity and supplied to the respective conductors, and the second inspection signal is the second. A third state in which one of the one polarity and the second polarity is output and supplied to each conductor, and the second inspection signal is sent to the other polarity of the first polarity and the second polarity. The switching process of switching between the fourth state of outputting and supplying to each conductor is executed.
The inspection unit has a first resistance value as the resistance value measured by the measurement unit in the first state, and a second resistance value as the resistance value measured by the measurement unit in the second state. The resistance value , the third resistance value as the resistance value measured by the measuring unit in the third state , and the fourth resistance as the resistance value measured by the measuring unit in the fourth state. When the mutual relationship between the values satisfies a predetermined condition and all of the resistance values are less than the values indicating the insulation state, the connection state between the conductors is judged to be good, and the first to fourth values are determined. When the mutual relationship between the resistance values does not satisfy the above conditions and at least one of the resistance values is at least one of the values indicating the insulation state, the connection state between the conductors is determined to be defective. An inspection device that executes a judgment process. The inspection device according to claim 1, wherein the inspection unit executes the determination process on the condition that all of the mutual ratios of the first to fourth resistance values are within a predetermined reference range. The inspection device according to claim 1 or 2, wherein the control unit switches the first state, the second state, the third state, and the fourth state in this order in the switching process. In the inspection unit, when the first resistance value is less than the value indicating the insulating state and the second resistance value is equal to or more than the value indicating the insulating state, and the second resistance value indicates the insulating state. When the value is less than the value and the first resistance value is equal to or more than the value indicating the insulation state, the connection state between the conductors is determined to be a polarity dependence defect in which the resistance value differs depending on the polarity. The inspection device according to claim 3. In the inspection unit, the ratio of the first resistance value to the second resistance value is within the reference range, and the ratio of the first resistance value to the third resistance value or the second resistance value. 3. Claim 3 in which when the ratio of the resistance value to the third resistance value is out of the reference range, the connection state between the conductors is determined to be a current value dependence defect in which the resistance value differs depending on the difference in the current value. Or the inspection device according to 4. An inspection method in which the resistance value between the conductors is measured while the inspection signals are supplied to a plurality of conductors connected to each other, and the connection state between the conductors is inspected based on the measured resistance value. There,
The first inspection signal as the inspection signal whose current value is defined by the first current value and the upper limit of the voltage value is defined by the first voltage value is the first polarity and the second polarity is inverted. The first state in which one of the polarities is output and supplied to the respective conductors, and the first inspection signal is output in the other polarity of the first polarity and the second polarity. The second state of supply to the conductor and the second current value whose current value is larger than the first current value are defined, and the upper limit of the voltage value is defined by the second voltage value which is larger than the first voltage value. A third state in which a second inspection signal as the inspection signal is output in one of the first polarity and the second polarity and supplied to each conductor, and the second inspection signal. A switching process for switching between a fourth state in which a signal is output with the other polarity of the first polarity and the second polarity and supplied to the respective conductors is executed.
First resistance value as the resistance value measured in the first state, the second resistance value as said resistance value measured in the second state, the said resistance value measured in the third state The mutual relationship between the third resistance value and the fourth resistance value as the resistance value measured in the fourth state satisfies a predetermined condition, and all of the resistance values indicate an insulating state. When it is less than, it is judged that the connection state between the conductors is good, and when the mutual relationship between the first to fourth resistance values does not satisfy the above conditions and one or more of the resistance values is the insulating state. An inspection method for executing a determination process for determining the connection state between the conductors as defective when the value is equal to or greater than the value indicating.

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