JP2008076349A - Inspection apparatus and inspection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection apparatus capable of accurately inspecting a wiring pattern formed on a circuit substrate. <P>SOLUTION: The inspection apparatus 11 capable of inspecting a wiring pattern 3, formed on a circuit substrate 5, via which a bump 1 formed on the circuit substrate 5 and an external connection terminal 2 formed on the circuit substrate 5 are connected includes: a charging device 12 for charging the bump 1 so that the bump 1 has a first potential Vt; a measuring section 19 for measuring at least either the potential of the external connection terminal 2 or the electrical current I1 flowing between the bump 1 and the external connection circuit 2; and a processing section 19 for inspecting the wiring pattern 3 in accordance with at least either of the values measured by the measuring section 19. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inspection apparatus capable of inspecting a wiring pattern of a circuit board that connects one specific part (for example, a bump of the circuit board) formed on the circuit board and another specific part (for example, an external connection terminal). It is about the method.

  As this type of inspection apparatus, an inspection apparatus (substrate inspection apparatus) disclosed in Japanese Patent No. 2994259 is known. This inspection apparatus is a circuit board inspection apparatus for testing the quality of a conductive path in a circuit board provided with an electrode terminal group having an interval that can be individually contacted and a narrow-pitch conductive path row connected to the electrode terminal group. A contact probe group connected in contact with each of the electrode terminal groups, a sensor electrode having a facing surface facing the surface of the circuit board and provided with a shield for interfering with the radiation wave, and a sensor The opposing surface of the electrode is brought close to the conductive path array in a non-contact manner, the probe is brought into contact with an arbitrary first electrode terminal of the electrode terminal group, and an inspection signal including an AC component is supplied. The circuit board by evaluating means for supplying a ground potential by bringing another probe into contact with the second electrode terminal other than the electrode terminal and a signal of the radiated wave detected by the opposing surface of the non-contact sensor electrode Discriminating means for discriminating whether or not there is a defect, the opposing surface of the sensor electrode has a length that can cover the conductive path row in the row direction, and the shield radiates from the conductive path on the first electrode terminal side. It arrange | positions and is comprised so that it may interrupt that the radiated wave to reach | attain the opposing surface of a sensor electrode.

According to this inspection apparatus, since non-contact probing is formed on the inspection target electrode (group) on the narrow pitch side of the conductor pattern and physical contact is unnecessary, disconnection of a flexible substrate having a narrow conductor pattern, etc. In the substrate inspection, it is possible to eliminate the difficulty of conventional blowing by the contact probe, and to satisfy more stringent test requirements.
Japanese Patent No. 2994259 (pages 2, 6 and 1)

  However, the above inspection apparatus has the following problems. That is, in this inspection apparatus, when the arrangement of sensor electrodes (non-contact sensor electrodes) that are brought close to each other in a non-contact manner with respect to the conductive path row is changed, it is formed between the conductive path row to be inspected and the sensor electrode. The capacitance value of the coupling capacitance changes, and the level of the signal detected by the sensor electrode also changes due to the change in the capacitance value. For this reason, this inspection apparatus has a problem that the inspection becomes unstable and it is difficult to perform an accurate inspection.

  Further, in this inspection apparatus, a conductive path row (first electrode) to be inspected is supplied by supplying a ground potential to a conductive path row (connected to the second electrode terminal) that is not an inspection target. That are connected to the terminal). However, the configuration itself for supplying the ground potential individually to the conductive path row not to be inspected is complicated, and the sensor electrode is to be inspected even if the ground potential is supplied to the conductive path row not to be inspected. As a result, the inspection signal supplied to the first electrode terminal also flows through the coupling capacitance through the conductive path row not to be inspected. For this reason, this inspection apparatus also has a problem that accurate inspection is difficult as a result of not being able to completely eliminate the influence of the conductive path row that is not the inspection target.

  The present invention has been made in view of such a problem, and a main object of the present invention is to provide an inspection apparatus and an inspection method capable of accurately inspecting a wiring pattern formed on a circuit board.

  To achieve the above object, the inspection apparatus according to claim 1 is an inspection apparatus capable of inspecting a wiring pattern formed on the circuit board that connects one specific part formed on the circuit board and another specific part. And charging at least one of a charging device for charging the one specific part to a first potential, a potential of the other specific part, and a current flowing between the one specific part and the other specific part. A measuring unit for measuring, and a processing unit for inspecting the wiring pattern based on the at least one value measured by the measuring unit.

  The inspection apparatus according to claim 2 is the inspection apparatus according to claim 1, wherein a voltage dividing resistor having one end connected to the other specific part and a reference for applying a second potential to the other end of the voltage dividing resistor. A potential applying unit; and the processing unit is configured to determine a resistance value of the wiring pattern based on the potential measured by the measuring unit, the first potential, the second potential, and a resistance value of the voltage dividing resistor. And the wiring pattern is inspected based on the calculated resistance value.

  According to a third aspect of the present invention, there is provided the inspection apparatus according to the first or second aspect, further comprising a non-contact measurement unit that measures the first potential.

  The inspection apparatus according to claim 4 is the inspection apparatus according to claim 1, wherein one end is connected to the other specific portion, and the resistance value can be switched between at least a first resistance value and a second resistance value. And a reference potential applying unit that applies a second potential to the other end of the voltage dividing resistor, and the measuring unit has at least a resistance value of the voltage dividing resistor. The potential of the other specific part at the time of the resistance value and the second resistance value is measured, respectively, and the processing unit is configured to measure each potential measured by the measurement unit, at least the first resistance value, and A resistance value of the wiring pattern is calculated based on the second resistance value, and the wiring pattern is inspected based on the calculated resistance value.

  The inspection apparatus according to claim 5, further comprising a reference potential applying unit that applies a second potential to the other specific part in the inspection apparatus according to claim 1, wherein the processing unit includes the measured current, A resistance value of the wiring pattern is calculated based on the first potential and the second potential, and the wiring pattern is inspected based on the calculated resistance value.

  The inspection apparatus according to claim 6 is the inspection apparatus according to any one of claims 1 to 5, wherein the charging device generates at least one of positive ions and negative ions, and the ions are ducted. Is supplied to the one specific part to charge the one specific part to the first potential.

  The inspection device according to claim 7 is the inspection device according to any one of claims 1 to 5, further comprising a cover that covers the one specific part, wherein the charging device is at least one of + ion and − ion. Are generated, and the ions are supplied into the cover to charge the one specific portion to the first potential.

  The inspection method according to claim 8 is an inspection method for inspecting a wiring pattern connecting one specific portion formed on a circuit board and another specific portion, and the one specific portion is detected using a charging device. Charge to a first potential, measure at least one of the potential of the other specific part and the current flowing between the one specific part and the other specific part, and the measured at least one value An inspection method for inspecting the wiring pattern based on the above.

  In the inspection apparatus according to claim 1, by using the charging device, for example, one specific portion of the circuit boards arranged in parallel at a fine pitch so that a predetermined potential cannot be individually applied using a probe or the like is used. 1 can be reliably charged. In other words, the same first potential can be reliably applied to one specific part. Moreover, as a result of being able to apply the same first potential to all of one specific portion, the potentials of the wiring pattern and the external connection terminal on the circuit board connected to the portion other than the inspection target are also the same first potential at the same time. Can be granted. Therefore, according to this inspection apparatus, unlike a conventional inspection apparatus, a special mechanism for supplying a ground potential or the like to a wiring pattern other than the inspection target can be eliminated, and the apparatus configuration is simplified. be able to. Also, according to this inspection device, unlike the conventional inspection device, since the configuration does not use capacitive coupling, it is possible to reliably avoid a situation where the inspection becomes unstable due to a change in the capacitance value of the coupling capacitance. Therefore, accurate inspection can be performed.

  Further, according to the inspection apparatus of the second aspect, since only one voltage dividing resistor is used, the apparatus configuration can be simplified, and the apparatus cost can be greatly reduced.

  According to a third aspect of the present invention, there is provided a non-contact measuring unit that measures the first potential in a non-contact manner, whereby the first potential is charged (applied to one specific part by the charging device). ) The first potential on the surface of one specific part can be accurately measured in real time without affecting the operation. Therefore, according to this inspection apparatus, even if the first potential of one specific part varies, the resistance value of the wiring pattern between one specific part and another specific part can be reliably calculated. Inspection of the wiring pattern can be performed accurately.

  According to the inspection apparatus of the fourth aspect, based on each potential measured by the measurement unit, at least the first resistance value and the second resistance value, the processing unit uses, for example, 2 as parameters. By solving at least two equations that hold for two potentials or using the least square method, the resistance value of the wiring pattern can be calculated from the above parameters, and the wiring pattern can be inspected based on the resistance value. Therefore, according to this inspection apparatus, by using the voltage dividing resistor configured to switch the resistance value between the first resistance value and the second resistance value, the potential of one specific part is measured. The arrangement of the non-contact measuring unit can be eliminated.

  According to the inspection apparatus of claim 5, the processing unit calculates the resistance value of the wiring pattern based on the measured current, the first potential, and the second potential, thereby distributing the voltage dividing resistor. Since the installation can be omitted, the configuration of the apparatus can be simplified. In addition, since the resistance value of the wiring pattern can be calculated with a small number of steps, the time required for the arithmetic processing can be shortened and thus the inspection time can be shortened.

  According to the inspection apparatus of claim 6, the charging device supplies the ion for charging one specific part to the first potential to the one specific part through the duct, thereby specifying one specific part. Ions can be reliably supplied to the site and charged to the first potential. Further, the use of the duct can increase the degree of freedom with respect to the arrangement position of the charging device with respect to the inspection position of the circuit board. As a result, for example, the charging device can be arranged at a position where the inspection apparatus can be minimized.

  The inspection apparatus according to claim 7 covers one specific part with the cover, and the charging device supplies the ions for charging the one specific part to the first potential in the cover. As a result of being able to apply ions to a specific part efficiently and substantially uniformly, even when there are a plurality of one specific part, all the one specific part can be charged to the first potential.

  In the inspection method according to claim 8, by using the charging device, for example, a specific portion of one of the circuit boards arranged in parallel at a fine pitch that cannot be individually applied with a predetermined potential using a probe or the like is used. 1 can be reliably charged. In other words, the same first potential can be reliably applied to one specific part. Moreover, as a result of being able to apply the same first potential to all of one specific part, the same first potential is also applied to the potentials of the wiring pattern and the external connection terminal connected to the part other than the inspection target at the same time. Can do. Therefore, according to this inspection method, since the capacitive coupling with one specific part is not used, it is possible to reliably avoid the situation where the inspection becomes unstable due to the change in the capacitance value of the coupling capacitance. Therefore, an accurate inspection can be performed.

  The best mode of an inspection apparatus and an inspection method according to the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, a plurality of bumps 1 (one specific portion in the present invention) are formed on one surface 4 a as an inspection object of the inspection apparatus, and correspond to the plurality of bumps 1. The external connection terminals 2 (other specific parts in the present invention) are formed on the other surface 4b, and the wiring patterns 3 that connect the bumps 1 and the external connection terminals 2 to each other one-to-one are inside (and the surface). A circuit board 5 having a substrate body 4 formed on the substrate 4 and capable of flip-chip mounting a bare chip IC (not shown) on one surface 4a of the substrate body 4 will be described as an example. In recent years, bare chip ICs are constructed by forming an extremely large number of terminals in a region having a small area due to a drastic improvement in the degree of integration. For this reason, the bumps 1 of the circuit board 5 are also arranged side by side in a narrow area at the same fine pitch as that of the terminals of the bare chip IC (for example, a pitch of 0.2 mm or less).

  As shown in FIG. 1, the inspection device 11 includes a charging device 12, a cover 13, a duct 14, a detection probe 15, a scanner unit 16, a reference potential applying unit 17, a voltage dividing resistor 18, a measuring unit 19, and a non-contact measuring unit. 20, the processing part 21 and the display part 22 are provided, and it is comprised so that the connection state of each wiring pattern 3 of the circuit board 5 can be test | inspected by implementing the test | inspection method based on this invention.

  The charging device 12 operates when the control signal S1 is input, and generates at least one of + ions (plus ions) and − ions (negative ions) (also referred to as “ions” unless otherwise distinguished). At the same time, air (an example of gas) 12a containing the generated ions is sent out. In this example, the charging device 12 is configured using an ionizer (also referred to as a static elimination device) as an example. In general, an ionizer generates + ions and-ions, neutralizes charged objects with ions of opposite polarity, and generates only one of + ions and-ions. This is a device for charging the object to one of the positive and negative polarities. In addition, as a device for charging an object to one polarity, for example, there is a charge master (such as power supply CH-20, electrode pinner linear, etc.) manufactured by Simco Co., and these devices have, for example, different polarities between films. Used for the purpose of bonding by charging. There are two types of ionizers: a corona discharge ionizer that generates ions by applying a high voltage to the discharge needle, and a soft X-ray ionizer that generates ions using soft X-rays. Can do. Further, the charging device 12 of the present invention is configured to be able to independently control the amount of both + ions and − ions to be generated under the control of the processing unit 21. With this configuration, the charging device 12 can charge all the bumps 1 of the circuit board 5 to the same potential (DC potential) Vt (first potential in the present invention) as will be described later (all bumps). 1 can be given the same potential Vt), and the potential Vt can be changed freely. Note that the potential (DC potential) Vt in the present invention refers to DC itself or DC on which an AC component having a very low frequency (for example, 1 Hz or less) is superimposed.

  The cover 13 is formed in a cup shape whose outer shape can cover the formation area of the bump 1 on the circuit board 5. In this example, the cover 13 is formed in a cup shape having a rectangular shape (or square) in plan view, as shown in FIG. 1, in accordance with the shape of the bare chip IC whose plan view shape is generally rectangular or square. . However, it is needless to say that the present invention is not limited to this shape and may be formed in other shapes such as a circular shape in plan view. The cover 13 is disposed so that the opening portion faces the circuit board 5 disposed at the inspection position. Further, a hole (not shown) communicating with the charging device 12 through the duct 14 is formed on the bottom surface of the cover 13. With this configuration, the air 12 a sent from the charging device 12 is supplied into the cover 13 via the duct 14.

  The detection probes 15 are provided in the same number as the external connection terminals 2 of the circuit board 5 and are configured to be connectable to the corresponding external connection terminals 2 on the circuit board 5 when the circuit board 5 is disposed at the inspection position. . Since each external connection terminal 2 of the circuit board 5 is formed with a sufficiently wide pitch compared to the bump 1, each detection probe 15 can be connected simultaneously with the corresponding external connection terminal 2.

  As shown in FIG. 1, the scanner unit 16 includes a plurality (the same number as the detection probes 15) of switches 16 a. In this case, each switch 16 a has one contact point connected to the corresponding detection probe 15 on a one-to-one basis, and the other contact point is connected in common and connected to the voltage dividing resistor 18. In addition, the scanner unit 16 shifts each switch 16a to an on state or an off state so that one detection probe 15 specified by the input control signal S2 is connected to the voltage dividing resistor unit 18. The reference potential applying unit 17 generates a DC voltage having a preset voltage value, and applies the generated DC voltage as the reference potential Vr (second potential in the present invention) to the voltage dividing resistor unit 18.

  The voltage dividing resistor 18 includes one or two or more voltage dividing resistors and is disposed between the reference potential applying unit 17 and the scanner unit 16 as shown in FIG. In this example, as an example, the voltage dividing resistor 18 is configured by one voltage dividing resistor 18a (resistance value: R1 (known)) as shown in FIG. Further, the voltage dividing resistor 18a is connected to the circuit board 5 through the scanner unit 16 and the detection probe 15 as shown in FIG. In the figure, the scanner unit 16 and the detection probe 15 are indicated by line segments because the resistance component is zero. With this configuration, the voltage dividing resistor 18 a is configured to obtain a potential difference (Vr−Vt) between the reference potential Vr applied from the reference potential applying unit 17 and the potential Vt applied to each bump 1, as a wiring pattern of the circuit board 5. 3 (resistance value: Rx (unknown)).

  The measuring unit 19 has a potential Vd at the connection point between the scanner unit 16 and the voltage dividing resistor unit 18 (on the external connection terminal 2 connected to this connection point via the switch 16a and the detection probe 15 in the ON state in the scanner unit 16). Measure the potential). The measuring unit 19 converts the measured potential Vd into digital data (voltage data) Dv and outputs the digital data (voltage data) Dv to the processing unit 21. The non-contact measuring unit 20 is disposed on the cover 13 to measure the surface potential (potential Vt) of the bump 1 covered with the cover 13 on the circuit board 5 in a non-contact manner, and the measured potential Vt is digital data (voltage). Data) converted to Dt and output to the processing unit 21. As the non-contact measuring unit 20, for example, a surface potential meter (Model 400) manufactured by Trek Japan Co., Ltd. that can measure a direct current potential in a non-contact manner can be used.

  The processing unit 21 is configured using a CPU, an internal memory, and the like (both not shown), and executes a calculation process of the resistance value Rx of the wiring pattern 3 and a determination process for the calculated resistance value Rx. Further, the processing unit 21 controls the operation of the charging device 12 and the scanner unit 16 by outputting the control signal S1 to the charging device 12 and the control signal S2 to the scanner unit 16. Further, the processing unit 21 causes the display unit 22 to display the calculated resistance value Rx. Further, in the internal memory of the processing unit 21, various parameters such as the resistance value R1 and the reference potential (voltage value) Vr of the voltage dividing resistor 18a used in the calculation process and the reference resistance value Rr used in the determination process. Is stored in advance.

  Next, the operation of the inspection apparatus 11 and the inspection method will be described. In this example, in order to facilitate understanding of the invention, each resistance component such as a contact resistance between the detection probe 15 and the external connection terminal 2, a resistance of the detection probe 15, a resistance of the switch 16 a in the ON state is used. The description will be made assuming that the resistance value is zero [Ω].

  First, the inspection apparatus 11 is arranged in a state where the circuit board 5 is arranged at the measurement position, all the bumps 1 of the circuit board 5 are covered with the cover 13, and each detection probe 15 is connected to the corresponding external connection terminal 2. Turn on the power. At this time, the reference potential applying unit 17 starts applying the reference potential Vr to the voltage dividing resistor 18, and the measuring unit 19 starts measuring the potential Vd and outputting the voltage data Dv. Further, the non-contact measuring unit 20 starts measuring the surface potential (potential Vt) of the bump 1 and outputting the voltage data Dt.

  Next, the processing unit 21 outputs a control signal S1 to the charging device 12 to cause the charging device 12 to start sending out air 12a containing a certain amount of + ions and a certain amount of − ions. In this case, the sent air 12a is supplied to the inside of the cover 13 via the duct 14, and is efficiently and almost uniformly applied to all the bumps 1 of the circuit board 5 covered with the cover 13 (blowing). ). In this state, a predetermined potential Vt is applied to the surface of the bump 1 in accordance with the amount of + ions and − ions contained in the air 12a (the surface of the bump 1 is charged to the predetermined potential Vt). . Specifically, when the same amount of + ions and − ions are contained, the bump 1 is in an electrically neutralized state, and its potential Vt becomes zero volts. When more positive ions are included than negative ions, the bump 1 is positively charged and the potential Vt is positive. Conversely, negative ions are included more than positive ions. The bump 1 is negatively charged and the potential Vt becomes a negative potential. Therefore, in any state, since the amount of + ions and − ions contained in the air 12a is constant, the potentials of all the bumps 1 are maintained at the same potential Vt. Further, as will be described later, even when the current I1 flows from the reference potential applying unit 17 to the bump 1, the surface of the bump 1 is always supplied with ions from the charging device 12 (that is, from the charging device 12). Because the power is supplied), the potentials of all the bumps 1 are maintained at the same potential Vt.

  In this example, the diffusion of the air 12a supplied to the vicinity of each bump 1 through the duct 14 is suppressed by the cover 13, and even when the formation area of the bump 1 is wide, all the bumps 1 are efficiently formed. When the circuit board 5 that allows the air 12a to diffuse to some extent, such as the circuit board 5 in which the formation area of the bump 1 is narrow, is configured to be applied. The arrangement of the cover 13 can be omitted. Further, even in a configuration in which the area of the opening of the duct 14 is wide enough to sufficiently cover the formation area of the bump 1, the air 12 a can be almost uniformly applied from all the bumps 1 to the cover 13. Can be omitted. Further, in this example, by using the duct 14, the degree of freedom regarding the arrangement position of the charging device 12 with respect to the inspection position of the circuit board 5 is increased, and the configuration of the charging device 12 and the charging device in the inspection device 11 are increased. Regardless of the positional relationship between the circuit board 5 and the circuit board 5, the air 12 a containing ions generated by the charging device 12 can be reliably supplied to the circuit board 5 through the duct 14. Depending on the configuration of 12, the air outlet 12a (not shown) of the air 12a may be arranged in the vicinity of the inspection position of the circuit board 5. In such a configuration, the arrangement of the duct 14 is also omitted, and the charging device The air 12a can be directly applied to the bump 1 from the 12 outlets.

  Subsequently, the processing unit 21 outputs a control signal S2 to the scanner unit 16 to turn on one switch 16a and shift the remaining switch 16a to an off state. As a result, the voltage dividing resistor 18 is electrically connected to one external connection terminal 2 of the circuit board 5 through one switch 16a that has been turned on and the detection probe 15 that is connected to the switch 16a. The

  Next, the processing unit 21 executes a calculation process of the resistance value Rx. In this calculation process, the processing unit 21 first calculates a potential difference (Vr−Vd) between the reference potential Vr and the potential Vd indicated by the input voltage data Dv, and the calculated potential difference (Vr−Vd) By dividing by the resistance value R1 of the voltage dividing resistor 18a read from the memory, the current value of the current I1 flowing through the voltage dividing resistor 18a due to the potential difference (Vr−Vt) between the reference potential Vr and the potential Vt is calculated. To do. In this case, between the reference potential Vr and the potential Vt, the voltage dividing resistor 18 (voltage dividing resistor 18a), the scanner unit 16 (one switch 16a in the ON state), one detection probe 15, and one There is only one path formed by the external connection terminal 2, one wiring pattern 3, and one bump 1, and the detection probe 15, switch 16a, external connection terminal 2, wiring pattern 3, and substrate body 4 in this path exist. Is capacitively coupled to a neighboring object of the same type or an object external to the inspection apparatus 11 via a stray capacitance. However, in this inspection apparatus 11, the reference potential Vr and the potential Vt are both DC. The current value of the current I1 can be accurately calculated without being affected by such stray capacitance.

  Next, the processing unit 21 calculates a potential difference (Vd−Vt) between the potentials Vd and Vt indicated by the input voltage data Dv and Dt, and divides the calculated potential difference (Vd−Vt) by the current value of the current I1. As a result, the resistance value Rx of the wiring pattern 3 is calculated and stored in the internal memory. Thereby, the calculation process of the resistance value Rx for one wiring pattern 3 is completed. Thereafter, the processing unit 21 outputs the control signal S2 to the scanner unit 16 and shifts the remaining switches 16a one by one while executing the above calculation process, whereby all wiring of the circuit board 5 is performed. The resistance value Rx for the pattern 3 is calculated and sequentially stored in the internal memory.

  Next, the processing unit 21 executes a determination process of the resistance value Rx. In this determination process, the processing unit 21 first compares the resistance values Rx of all the wiring patterns 3 stored in the internal memory with the reference resistance value Rr stored in the internal memory, and determines each resistance value. It is determined whether or not Rx is less than or equal to the reference resistance value Rr. As a result of the determination, when the resistance value Rx is equal to or less than the reference resistance value Rr, the processing unit 21 determines that the wiring pattern 3 is in a good state without being disconnected. On the other hand, when the resistance value Rx exceeds the reference resistance value Rr, the wiring pattern 3 may be disconnected or locally thinned. Therefore, the processing unit 21 determines that the wiring pattern 3 is in a defective state. Determine. Next, the processing unit 21 stores the determination result for each wiring pattern 3 in the internal memory. Thereby, the discrimination process is completed.

  Finally, the processing unit 21 reads out the result of the discrimination process from the internal memory and displays it on the display unit 22. Thereby, the inspection of the wiring pattern 3 for the circuit board 5 is completed.

  As described above, in the inspection device 11 and the inspection method, by using the charging device 12, a plurality of circuit boards 5 arranged in parallel at a fine pitch that cannot be individually applied with a predetermined potential using, for example, a probe or the like. The bump 1 can be reliably charged to the same potential Vt. In other words, the same potential Vt can be reliably applied to the plurality of bumps 1. Moreover, as a result of being able to apply the same potential Vt to all the bumps 1, the potentials of the wiring pattern 3 and the external connection terminals 2 connected to the bumps 1 other than the inspection target can be simultaneously applied with the same potential Vt. Therefore, according to this inspection apparatus 11, unlike the conventional inspection apparatus, a special mechanism for supplying the ground potential or the like to the wiring pattern 3 other than the inspection object can be eliminated, and the apparatus configuration is simplified. Can be In addition, according to the inspection apparatus 11 and the inspection method, since the configuration does not use capacitive coupling, it is possible to reliably avoid a situation where the inspection becomes unstable due to a change in the capacitance value of the coupling capacitance. Accurate inspection can be performed.

  In addition, according to this inspection device 11, since only one voltage dividing resistor 18a is used, the device configuration can be simplified, resulting in a significant reduction in device cost. In addition, according to the inspection apparatus 11, one end of the voltage dividing resistor 18a is connected to the external connection terminal 2 via the scanner unit 16 and the detection probe 15, and the other end of the voltage dividing resistor 18a is connected to the reference potential applying unit 17. Since the reference potential Vr is applied, the processing unit 21 performs an inspection based on the potential Vd, the potential Vt, the reference potential Vr, and the resistance value R1 of the voltage dividing resistor 18a measured by the measuring unit 19. As a result of the reliable calculation of the resistance value Rx of the wiring pattern 3, the wiring pattern 3 can be accurately inspected based on the resistance value Rx.

  In addition, according to the inspection apparatus 11, since the non-contact measurement unit 20 that measures the potential Vt in a non-contact manner is provided, the charging (applying) operation of the potential Vt to the bump 1 by the charging device 12 is affected. In addition, the potential Vt on the surface of the bump 1 can be accurately measured in real time. Therefore, according to this inspection apparatus 11, even if the potential Vt of the bump 1 fluctuates, the resistance value Rx of the wiring pattern 3 can be calculated reliably, so that the inspection of the wiring pattern 3 can be performed accurately.

  Note that the present invention is not limited to the embodiment of the invention described above, and can be modified as appropriate. For example, in the above-described embodiment, the example in which the potential Vt of the surface of each bump 1 is measured using the non-contact measuring unit 20 has been described. However, + ions contained in the air 12a sent from the charging device 12 The relationship between each amount (or each ratio) of ions and − and the potential Vt applied to each bump 1 of the circuit board 5 is obtained in advance by experiment, and the experimental data is stored in the internal memory of the processing unit 21 in advance. By doing so, the processing unit 21 can specify the potential Vt of each bump 1 from each amount (or each ratio) of + ions and − ions contained in the air 12a. Therefore, in this configuration, the arrangement of the non-contact measuring unit 20 can be omitted. Further, the charging device 12 can be adjusted in advance so that the potential Vt applied to the bump 1 becomes zero volts. According to this configuration, it is not necessary for the charging device 12 to change each amount (or each ratio) of + ions and − ions contained in the air 12a according to the control of the processing unit 21, and thus the configuration of the charging device 12 is simplified. Can be

  In the above-described embodiment, an example in which one voltage dividing resistor 18a is provided has been described. However, the resistance value is configured to be switchable between at least a first resistance value and a second resistance value. A voltage dividing resistor can also be used. Specifically, like the voltage dividing resistor 28 shown in FIG. 4, a voltage dividing resistor 18b having a resistance value R2 (known) different from the resistance value R1 of the voltage dividing resistor 18a and two switches 18c and 18d are added. Thus, a configuration in which the two voltage dividing resistors 18a and 18b can be switched and connected to the scanner unit 16 is adopted. More specifically, the voltage dividing resistor 28 includes a resistor 18a and a switch 18c connected in series, a resistor 18b and a switch 18d connected in series, and these two series circuits connected in parallel to each other. It is configured. The voltage dividing resistor 28 is controlled so that one of the switches 18c and 18d is turned on and the other is turned off in accordance with the control signal S3 output from the processing unit 21, so that the resistance as a whole The value can be switched between a resistance value R1 (first resistance value in the present invention) and a resistance value R2 (second resistance value in the present invention).

  Hereinafter, the inspection apparatus 11A provided with the voltage dividing resistor 28 will be described. Since the configuration is substantially the same as that of the inspection apparatus 11 except that the voltage division resistance section 28 is provided instead of the voltage division resistance section 18, the description of the configuration is omitted, and only the operation different from that of the inspection apparatus 11 is described. . Moreover, about the same structure as the test | inspection apparatus 11, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  In this inspection apparatus 11A, in the arithmetic processing, the processing unit 21 first outputs the control signal S3 to the voltage dividing resistor unit 28 to shift one switch 18c to the on state and the remaining switch 18d to the off state. Let Thereby, as shown in FIG. 5, the reference potential applying unit 17 is electrically connected to the scanner unit 16 through the one switch 18c and the voltage dividing resistor 18a that are turned on, and further through the detection probe 15. Connected to the circuit board 5. In the figure, the scanner unit 16 and the detection probe 15 are indicated by line segments because the resistance component is zero. Next, the processing unit 21 stores the potential Vd (potential Vd1 in this example) indicated by the input voltage data Dv in the internal memory.

  Subsequently, the processing unit 21 outputs the control signal S3 to the voltage dividing resistor unit 28, shifts one switch 18c to an off state, and shifts the remaining switch 18d to an on state. Thus, the reference potential applying unit 17 is electrically connected to the scanner unit 16 through the switch 18d and the voltage dividing resistor 18b that have been turned on, and is further connected to the circuit board 5 through the detection probe 15. Next, the processing unit 21 stores the potential Vd (potential Vd2 in this example) indicated by the input voltage data Dv in the internal memory.

  Next, the processing unit 21 calculates the resistance value Rx of the wiring pattern 3 based on the two potentials Vd1 and Vd2 and the two resistance values R1 and R2 stored in the internal memory. In the calculation process in the inspection apparatus 11A, one equation for the potential Vd1 using the reference potential Vr, the potential Vt, the resistance value R1, and the resistance value Rx as parameters is established, and the reference potential Vr, the potential Vt, the resistance value R2, and the like. There is one equation for the potential Vd2 with the resistance value Rx as a parameter. By solving these two equations, even if these values are unknown under the condition that the reference potential Vr and the potential Vt are constant values, The resistance value Rx of the wiring pattern 3 can be calculated based on the two potentials Vd1, Vd2 and the two resistance values R1, R2. Therefore, according to this inspection apparatus 11A, the same effect as that of the inspection apparatus 11 can be obtained, and the potential Vt of the bump 1 can be obtained by using the voltage dividing resistor portion 28 constituted by the two voltage dividing resistors 18a and 18b. It is possible to eliminate the need for the non-contact measurement unit 20 for measuring It should be noted that three or more resistance values of the voltage dividing resistors in the voltage dividing resistor portion 28 can be switched, and the wiring pattern 3 is based on each potential measured by the measuring unit 19 and the resistance value of each voltage dividing resistor. It is also possible to inspect the wiring pattern 3 based on the calculated resistance value. Moreover, it can replace with the structure which switches the above-mentioned several voltage dividing resistance, and the structure using a variable resistance is also employable. For example, in FIG. 5, a variable resistor (one as an example) is used in place of the voltage dividing resistor 28, and the resistance value of the variable resistor is changed in at least two stages to switch the voltage dividing resistor. Similarly, the resistance value of the wiring pattern 3 can be calculated and inspected.

  In the above-described embodiment, an example in which the voltage dividing resistor 18 (or 28) and the measuring unit 19 are provided and the potential Vd at the connection point between the scanner unit 16 and the voltage dividing resistor 18 is measured has been described. However, instead of measuring the voltage, an ammeter (DC ammeter) 31 is interposed between the scanner unit 16 and the reference potential applying unit 17 as in the inspection apparatus 11B shown in FIG. It is also possible to adopt a configuration in which a current I1 flowing between the reference potential applying unit 17 (that is, a current flowing through the wiring pattern 3 being inspected) is measured.

  Hereinafter, the inspection apparatus 11B will be described. In addition, about the structure same as the test | inspection apparatus 11, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  As shown in FIG. 6, the inspection device 11B includes a charging device 12, a cover 13, a duct 14, a detection probe 15, a scanner unit 16, a reference potential applying unit 17, an ammeter 31, a non-contact measuring unit 20, a processing unit 21, and A display unit 22 is provided, and the connection state of each wiring pattern 3 on the circuit board 5 is inspected. In this case, the ammeter 31 constitutes a measuring unit according to the present invention, and is disposed between the scanner unit 16 and the reference potential applying unit 17 as described above, and the current value of the current I1 flowing through the wiring pattern 3. And the measured current value of the current I1 is converted into digital data (current data) Di and output to the processing unit 21.

  In this inspection apparatus 11B, the processing unit 21 calculates a potential difference (Vr−Vt) between the reference potential Vr and the potential Vt indicated by the input voltage data Dt in the arithmetic processing, as a current I1 indicated by the input current data Di. The resistance value Rx of the wiring pattern 3 is calculated by dividing by this current value. According to the inspection device 11B, the arrangement of the voltage dividing resistor 18 can be omitted, so that the configuration of the device can be simplified. Moreover, since the resistance value Rx can be calculated with a small number of steps as described above, the time required for the arithmetic processing can be shortened, and thus the inspection time can be shortened.

  In the above-described embodiment, the circuit board (so-called package board) provided with the bumps 1 is described as an example of the inspection target. However, the present invention is not limited to this and is not limited to this. Of course, the present invention can be applied to a printed board, a flexible board, a flat panel display board, and the like.

It is a block diagram which shows the structure of the test | inspection apparatus 11 (11A). 3 is a circuit diagram of a voltage dividing resistor section 18. FIG. This is an equivalent circuit from the voltage dividing resistor 18 to the circuit board 5. 3 is a circuit diagram of a voltage dividing resistor section 28. FIG. This is an equivalent circuit from the voltage dividing resistor 28 to the circuit board 5. It is a block diagram which shows the structure of the test | inspection apparatus 11B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bump 2 External connection terminal 3 Wiring pattern 5 Circuit board 11, 11A, 11B Inspection apparatus 12 Charging apparatus 17 Reference potential provision part 19 Measurement part 18, 28 Voltage dividing resistance part 18a, 18b Voltage dividing resistance 21 Processing part Rx Resistance value Vt First potential Vd Second potential

Claims (8)

An inspection device capable of inspecting a wiring pattern connecting one specific part formed on a circuit board and another specific part,
A charging device for charging the one specific portion to a first potential;
A measurement unit that measures at least one of the electric potential of the other specific part and the current flowing between the one specific part and the other specific part;
An inspection apparatus comprising: a processing unit that inspects the wiring pattern based on the at least one value measured by the measurement unit. A voltage dividing resistor having one end connected to the other specific part;
A reference potential applying unit that applies a second potential to the other end of the voltage dividing resistor;
The processing unit calculates a resistance value of the wiring pattern based on the potential measured by the measuring unit, the first potential, the second potential, and a resistance value of the voltage dividing resistor, and calculates the calculated value. The inspection apparatus according to claim 1, wherein the wiring pattern is inspected based on a resistance value.   The inspection apparatus according to claim 1, further comprising a non-contact measurement unit that measures the first potential. One end connected to the other specific part, and a resistance for voltage division configured to be switchable between at least a first resistance value and a second resistance value,
A reference potential applying unit that applies a second potential to the other end of the voltage dividing resistor;
The measurement unit measures the potential of the other specific part when the resistance value of the voltage dividing resistor is at least the first resistance value and the second resistance value, respectively.
The processing unit calculates a resistance value of the wiring pattern based on each potential measured by the measurement unit, at least the first resistance value, and the second resistance value, and based on the calculated resistance value The inspection apparatus according to claim 1, wherein the wiring pattern is inspected. A reference potential applying unit that applies a second potential to the other specific portion;
The processing unit calculates a resistance value of the wiring pattern based on the measured current, the first potential, and the second potential, and inspects the wiring pattern based on the calculated resistance value. Item 1. The inspection apparatus according to Item 1.   The charging device generates at least one of positive ions and negative ions, and supplies the one specific part to the first specific part through a duct, thereby supplying the one specific part to the first specific part. The inspection apparatus according to claim 1, wherein the inspection apparatus is charged to a potential. A cover covering the one specific part;
The charging device generates at least one of positive ions and negative ions and supplies the ions into the cover to charge the one specific portion to the first potential. The inspection apparatus according to any one of 1 to 5. An inspection method for inspecting a wiring pattern that connects one specific part and another specific part formed on a circuit board,
Using the charging device to charge the one specific part to the first potential;
Measuring at least one of the electric potential of the other specific part and the current flowing between the one specific part and the other specific part;
An inspection method for inspecting the wiring pattern based on the measured at least one value.

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