Method for testing the continuity of a wiring circuit board and method for manufacturing a wiring circuit board

Abstract

To provide a continuity testing method for a printed circuit board and a method for manufacturing a printed circuit board that can improve the accuracy of continuity testing.SOLUTION: A printed circuit board includes a first terminal portion and a second terminal portion. A continuity tester 1 includes a first measurement probe 11 and a second measurement probe 12. The first measurement probe 11 branches into a plurality of contacts 11a and 11b. In a continuity test method for the printed circuit board, the first measurement probe 11 branched into the plurality of contacts 11a and 11b is brought into contact with the first terminal portion, and the second measurement probe 12 is brought into contact with the second terminal portion.SELECTED DRAWING: Figure 23

Description

Technical Field

[0001] The present invention relates to a continuity inspection method for a printed wiring board and a method for manufacturing a printed wiring board.

Background Art

[0002] A suspension substrate is a wired circuit used, for example, in a hard disk drive device to position a magnetic head on a desired track of a magnetic disk. Patent Document 1 describes a manufacturing process of a suspension substrate. In Patent Document 1, a plurality of suspension substrates are formed in a state of being integrally supported by a common support frame.

[0003] In each suspension substrate, an insulating layer is formed on a support substrate. A plurality of wiring patterns for connecting another electronic circuit and the magnetic head are formed on the insulating layer. Electrode pads are formed at both ends of each wiring pattern. In addition, a part of the wiring pattern is divided into a plurality of lines to avoid interference with other wiring patterns. The plurality of lines are electrically connected to a part of the support substrate through vias penetrating the insulating layer.

Prior Art Literature

Patent Literature

[0004]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0005] In the manufacturing process of a wiring circuit board, the quality of the wiring circuit board is determined by performing a continuity test between electrode pads or vias. In Patent Document 1, an inspection board is formed on a support frame, with vias having the same configuration as those on the wiring circuit board, and the continuity test of the inspection board is performed in place of the vias on the wiring circuit board. However, if the position where the jig is applied is shifted due to deformation of the substrate or the like, the wiring circuit board is often judged to be defective even though there is continuity between the electrode pads or vias.

[0006] The object of the present invention is to provide a method for testing the continuity of a wiring circuit board and a method for manufacturing a wiring circuit board that can improve the accuracy of the continuity test of the wiring circuit board. [Means for solving the problem]

[0007] A continuity testing method for a wiring circuit board according to one aspect of the present invention is a continuity testing method for a wiring circuit board having a first terminal portion and a second terminal portion, comprising: bringing a first measuring probe, which is branched into a plurality of contacts, into contact with the first terminal portion; and bringing a second measuring probe into contact with the second terminal portion. Furthermore, the multiple contacts of the first measuring probe are spaced apart from each other while their relative positional relationship remains unchanged. .

[0008] A method for manufacturing a wiring circuit board according to another aspect of the present invention includes forming a first terminal portion and a second terminal portion, bringing a first measuring probe branched into a plurality of contacts into contact with the formed first terminal portion, and bringing a second measuring probe into contact with the formed second terminal portion. Furthermore, the multiple contacts of the first measuring probe are spaced apart from each other while their relative positional relationship remains unchanged. . [Effects of the Invention]

[0009] According to the present invention, the accuracy of continuity testing of wiring circuit boards can be improved. [Brief explanation of the drawing]

[0010] [Figure 1] This is a top view of a circuit-equipped suspension substrate assembly sheet. [Figure 2] Figure 1 is a top view of the suspension substrate. [Figure 3] It is a schematic diagram showing the configuration of a writing wiring pattern. [Figure 4] It is a schematic cross-sectional view of the line of the writing wiring pattern and the peripheral portion thereof. [Figure 5] It is a diagram showing the intersection region of Fig. 3 and the periphery thereof. [Figure 6] It is a top view of an inspection substrate. [Figure 7] It is a cross-sectional view taken along line C-C of the inspection substrate of Fig. 6. [Figure 8] It is a schematic diagram showing the configuration of a continuity tester used in the continuity inspection method according to the present embodiment. [Figure 9] It is a schematic diagram showing an example of the continuity inspection method according to the present embodiment. [Figure 10] It is a schematic diagram showing a first modified example of the continuity inspection method. [Figure 11] It is a schematic diagram showing a second modified example of the continuity inspection method. [Figure 12] It is a schematic diagram showing a third modified example of the continuity inspection method. [Figure 13] It is a schematic diagram showing a fourth modified example of the continuity inspection method. [Figure 14] It is a schematic diagram showing a fifth modified example of the continuity inspection method. [Figure 15] It is a process cross-sectional view showing an example of a method for producing an assembly sheet according to an embodiment of the present invention. [Figure 16] It is a process cross-sectional view showing an example of a method for producing an assembly sheet according to an embodiment of the present invention. [Figure 17] It is a process cross-sectional view showing an example of a method for producing an assembly sheet according to an embodiment of the present invention. [Figure 18] It is a process cross-sectional view showing an example of a method for producing an assembly sheet according to an embodiment of the present invention. [Figure 19] It is a process cross-sectional view showing an example of a method for producing an assembly sheet according to an embodiment of the present invention. [Figure 20] It is a schematic diagram showing the configuration of a continuity tester according to another example. [Figure 21] It is a schematic top view showing an example of a jig. [Figure 22] It is a partially enlarged cross-sectional view of the jig of FIG. 21. [Figure 23] It is a diagram showing an example of a continuity tester according to another embodiment. [Figure 24] It is a diagram showing another example of a continuity tester according to another embodiment. [Figure 25] It is a diagram showing still another example of a continuity tester according to another embodiment. [Figure 26] It is a diagram showing an example of a continuity tester according to another embodiment. [Figure 27] It is a diagram showing the arrangement of measurement probes in Examples 1 to 3 and Reference Example 1. [Figure 28] It is a diagram showing the arrangement of measurement probes in Examples 1 to 3 and Reference Example 1. [Figure 29] It is a diagram showing inspection results of continuity tests in Examples 1 to 3 and Reference Example 1. [Figure 30] It is a diagram showing the ratio of defect determination in Example 4 and Reference Example 2. DESCRIPTION OF EMBODIMENTS

[0011] Hereinafter, a continuity inspection method for a printed wiring board and a method for manufacturing a printed wiring board according to an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, the wiring circuit board is a suspension board with circuit (hereinafter abbreviated as a suspension board).

[0012] (1) Suspension board with circuit assembly sheet Figure 1 is a top view of a circuit-equipped suspension substrate assembly sheet. The circuit-equipped suspension substrate (hereinafter abbreviated as assembly sheet 500) is a semi-finished product in the manufacturing process of the suspension substrate 100 and is made from a long, metal support substrate. As shown in Figure 1, the assembly sheet 500 has a rectangular shape. The assembly sheet 500 includes a support frame 510, a plurality of long, metal suspension substrates 100, and a plurality of inspection substrates 200.

[0013] In Figure 1, the two mutually orthogonal directions, indicated by arrows X and Y, are defined as the X and Y directions. In this example, the X and Y directions are parallel to the horizontal plane. The support frame 510 consists of a pair of side frames 511, 512 and a number of end frames 513, 514, 515, 516, 517, 518. The pair of side frames 511, 512 face each other and extend in the Y direction. The end frames 513 to 518 each extend in the X direction perpendicular to the pair of side frames 511, 512 and are formed to connect the pair of side frames 511, 512.

[0014] The end frames 513-518 are arranged in the Y direction at equal intervals from one end to the other of the pair of side frames 511, 512. This forms multiple (five in this example) rectangular regions 521, 522, 523, 524, and 525, separated by the side frames 511, 512 and the end frames 513-518. The multiple suspension substrates 100 are provided within the rectangular regions 521-525 so as to extend in the Y direction and be aligned in the X direction. Separation grooves 526 are formed along the outer edge of each suspension substrate 100.

[0015] Both ends of each suspension substrate 100 in the Y direction are connected to the support frame 510 via connecting portions 520. In this embodiment, the multiple inspection substrates 200 are formed on the end frames 513 to 517 on one end side of the multiple suspension substrates 100, so as to correspond to each of the multiple suspension substrates 100. In this example, the multiple inspection substrates 200 corresponding to each of the multiple suspension substrates 100 within the rectangular region 521 are formed on the end frame 513.

[0016] Similarly, multiple inspection boards 200 corresponding to multiple suspension boards 100 within the rectangular region 522 are formed within the end frame 514. Multiple inspection boards 200 corresponding to multiple suspension boards 100 within the rectangular region 523 are formed in the end frame 515. Multiple inspection boards 200 corresponding to multiple suspension boards 100 within the rectangular region 524 are formed in the end frame 516. Multiple inspection boards 200 corresponding to multiple suspension boards 100 within the rectangular region 525 are formed in the end frame 517.

[0017] In this way, multiple suspension substrates 100 are supported on the support frame 510 in an aligned state within each rectangular region 521 to 525. Multiple inspection substrates 200 are formed on the end frames 513 to 517. After the assembly sheet 500 is manufactured, the connecting portion 520 is cut, thereby separating each suspension substrate 100 from the support frame 510.

[0018] (2) Structure of the suspension board Figure 2 is a top view of the suspension substrate 100 of Figure 1. As shown in Figure 2, the suspension substrate 100 includes a support substrate 110 formed from a long, metal substrate. Writing wiring patterns 120, 130 and reading wiring patterns 140, 150 are formed on the support substrate 110, as shown by thick dotted lines. In Figure 2, the writing wiring patterns 120, 130 are shown by a single dotted line, and the reading wiring patterns 140, 150 are shown by a single dotted line. The writing wiring pattern 120 and the writing wiring pattern 130 constitute a pair of signal lines. The reading wiring pattern 140 and the reading wiring pattern 150 constitute a pair of signal lines.

[0019] A U-shaped opening 111 is formed at one end of the support substrate 110 to provide a magnetic head mounting section (hereinafter referred to as the tongue section 112). The tongue section 112 is bent at a predetermined angle with respect to the support substrate 110. Four electrode pads 161, 162, 163, and 164 are formed at the end of the tongue section 112.

[0020] Four electrode pads 165, 166, 167, and 168 are formed on the other end of the support substrate 110. The electrode pads 161 to 164 on the tongue portion 112 and the electrode pads 165 to 168 on the other end of the support substrate 110 are electrically connected by writing wiring patterns 120 and 130 and reading wiring patterns 140 and 150, respectively.

[0021] In a hard disk drive device (not shown) equipped with a suspension board 100, current flows through a pair of writing wiring patterns 120 and 130 when information is written to the magnetic disk. Also, current flows through a pair of reading wiring patterns 140 and 150 when information is read from the magnetic disk.

[0022] (3) Wiring pattern for writing The detailed configuration of the writing wiring patterns 120 and 130 will now be described. Figure 3 is a schematic diagram showing the configuration of the writing wiring patterns 120 and 130. As shown in Figure 3, the writing wiring pattern 120 is composed of lines 121 to 125. Line 121 is connected to electrode pad 161, and line 122 is connected to electrode pad 165. One end of lines 123 and 124 is integrated with line 121. The other end of line 123 and one end of line 125 are electrically connected in the intersection region 113. Details of the intersection region 113 will be described later. The other ends of lines 124 and 125 are integrated with line 122.

[0023] The writing wiring pattern 130 is composed of lines 131 to 135. Line 131 is connected to electrode pad 162, and line 132 is connected to electrode pad 166. One end of lines 133 and 134 is integrated with line 131. The other end of line 133 and one end of line 135 are electrically connected in the intersection region 114. Details of the intersection region 114 will be described later. The other ends of lines 134 and 135 are integrated with line 132.

[0024] The tracks 123 and 124 of the writing wiring pattern 120 and the tracks 134 and 135 of the writing wiring pattern 130 are arranged alternately and parallel to each other. Track 123 of the writing wiring pattern 120 extends through the gap between the ends of tracks 133 and 135 of the writing wiring pattern 130 in the crossing region 114, and track 135 of the writing wiring pattern 130 extends through the gap between the ends of tracks 123 and 125 of the writing wiring pattern 120 in the crossing region 113.

[0025] Figure 4 is a schematic cross-sectional view of the lines 123, 124, 134, 135 and their surrounding areas of the writing wiring patterns 120, 130. Figure 4 corresponds to the cross-sectional view of line AA in Figure 3. As shown in Figure 4, a base insulating layer 170 is formed on the support substrate 110. The lines 123, 124, 134, 135 of the writing wiring patterns 120, 130 are formed on the base insulating layer 170. A cover insulating layer 180 is formed on the base insulating layer 170 so as to cover the writing wiring patterns 120, 130.

[0026] Figure 5 shows the intersection region 113 and its surroundings in Figure 3. The upper part of Figure 5 shows a detailed plan view of the intersection region 113, and the lower part of Figure 5 shows a cross-sectional view of the intersection region 113 along line BB. Note that the intersection region 114 has a similar configuration to the intersection region 113.

[0027] As shown in Figure 5, an annular opening 115 is formed in the support substrate 110. This creates an island-like region 116 that is electrically isolated from other areas of the support substrate 110. A line 135 of the writing wiring pattern 130 is arranged to extend through the region 116 of the support substrate 110, with the ends of the lines 123 and 125 of the writing wiring pattern 120 positioned on either side of the line 135.

[0028] Circular connecting parts 126 and 127 are provided at the ends of track 123 and track 125, respectively. The shape of the connecting parts 126 and 127 is not limited to circles; they may be elliptical, triangular, square, or sector-shaped. Through holes 171 and 172 are formed in the base insulating layer 170 below the connecting parts 126 and 127. The through holes 171 and 172 are tapered, with their diameter gradually decreasing from the top to the bottom surface of the base insulating layer 170. The cross-sectional shape of the through holes 171 and 172 may be elliptical, triangular, square, or sector-shaped, respectively.

[0029] The connecting portion 126 contacts the region 116 of the support substrate 110 within the through hole 171, and the connecting portion 127 contacts the region 116 of the support substrate 110 within the through hole 172. A via 128 is formed by the portion of the connecting portion 126 within the through hole 171, and a via 129 is formed by the portion of the connecting portion 127 within the through hole 172. As a result, the lines 123 and 125 are electrically connected via the vias 128, 129 and the region 116 of the support substrate 110.

[0030] (4) Structure of the test substrate Figure 6 is a top view of the inspection substrate 200. Figure 7 is a cross-sectional view of the inspection substrate 200 of Figure 6 along the CC line. As shown in Figures 6 and 7, the inspection substrate 200 includes a support substrate 210 formed from a long, metal substrate. A base insulating layer 220 is formed on the support substrate 210. An opening 221 is formed in the base insulating layer 220. A portion of the support substrate 210 is exposed through the opening 221. Preferably, the opening 221 is formed so that a portion of the support substrate 210 with a length of 100 μm or more and 1500 μm or less is exposed.

[0031] Furthermore, through holes 222 are formed in the base insulating layer 220. A conductor layer 230 is formed on the base insulating layer 220. A portion of the conductor layer 230 contacts the support substrate 210 within the through holes 222. A via 231 is formed by the portion of the conductor layer 230 within the through holes 222. As a result, the conductor layer 230 and the support substrate 210 are electrically connected via the via 231. The via 231 has the same configuration as vias 128 and 129 in Figure 5.

[0032] A cover insulating layer 240 is formed on the base insulating layer 220 so as to cover the conductive layer 230. An opening 241 is formed in the cover insulating layer 240. A portion of the conductive layer 230, excluding the vias 231, is exposed through the opening 241. Preferably, the opening 241 is formed so as to expose a portion of the conductive layer 230 with a length of 100 μm or more and 1500 μm or less. In this example, the area of ​​the support substrate 210 exposed through the opening 221 is larger than the area of ​​the conductive layer 230 exposed through the opening 241.

[0033] In the manufacturing process of the suspension substrate 100 shown in Figure 2, continuity tests are performed between electrode pads 161-164 and electrode pads 165-168, as well as between vias 128 and 129. In this example, instead of testing vias 128 and 129, a continuity test is performed on via 231, and the test result of via 231 is used as the test result for vias 128 and 129.

[0034] (5) Method of testing for continuity Figure 8 is a schematic diagram showing the configuration of a continuity tester used in the continuity testing method according to this embodiment. As shown in Figure 8, the continuity tester 1 includes a power supply 10, a current measuring unit 20, a voltage measuring unit 30, and measuring probes 21, 22, 31, 32. Measuring probe 21 includes a plurality of contacts 21a, 21b, 21c, ... branched from the same node 21N. Measuring probe 31 includes a plurality of contacts 31a, 31b, 31c, ... branched from the same node 31N.

[0035] The contacts 21a, 21b, 21c, ... are electrically connected to node 21N. The contacts 21a, 21b, 21c, ... may be integrally formed from the same material. Similarly, the contacts 31a, 31b, 31c, ... are electrically connected to node 31N. The contacts 31a, 31b, 31c, ... may be integrally formed from the same material. The same applies to the other contacts described later.

[0036] In this example, the power supply 10 is an AC power supply, but it may also be a DC power supply. One terminal of the power supply 10 is connected to the measurement probe 21 via the current measurement unit 20. The other terminal of the power supply 10 is connected to the measurement probe 22. One terminal of the voltage measurement unit 30 is connected to the measurement probe 31. The other terminal of the voltage measurement unit 30 is connected to the measurement probe 32.

[0037] The following describes the continuity test of via 231 using the continuity tester 1. Figure 9 is a schematic diagram showing an example of the continuity test method according to this embodiment. The upper part of Figure 9 shows a cross-sectional view of the test substrate 200, and the lower part of Figure 9 shows a top view of the test substrate 200. The same applies to Figures 10 to 14, which will be described later. As shown in the upper part of Figure 9, in this example, the measuring probe 21 is branched into two contacts 21a and 21b, and the measuring probe 31 is branched into two contacts 31a and 31b. The distance between contacts 21a and 21b, and the distance between contacts 31a and 31b are smaller than the maximum length of the exposed portion of the conductor layer 230.

[0038] The measuring probes 21 and 31 are in contact with the exposed portion of the conductor layer 230, and the measuring probes 22 and 32 are in contact with the exposed portion of the support substrate 210. Here, if the area of ​​the exposed portion of the conductor layer 230 is small, it becomes difficult to bring the measuring probes 21 and 31 into contact with the conductor layer 230. Even in this case, the measuring probe 21 branches into contactors 21a and 21b, so the probability that at least one of the contactors 21a and 21b will come into contact with the conductor layer 230 is increased. Similarly, the measuring probe 31 branches into contactors 31a and 31b, so the probability that at least one of the contactors 31a and 31b will come into contact with the conductor layer 230 is increased.

[0039] As shown in the lower part of Figure 9, the contacts 21a, 21b, 31a, and 31b may be arranged in a 2x2 grid. In the example in Figure 9, contacts 21a and 21b are positioned diagonally, and contacts 31a and 31b are positioned diagonally. This arrangement allows for more reliable contact between at least one of contacts 21a and 21b, and at least one of contacts 31a and 31b, and the conductor layer 230, even if the measuring probes 21 and 31 are misaligned.

[0040] When the measuring probes 21 and 22 come into contact with the conductor layer 230 and the support substrate 210, respectively, contact resistances r1 and r2 are generated in the measuring probes 21 and 22. Similarly, when the measuring probes 31 and 32 come into contact with the conductor layer 230 and the support substrate 210, respectively, contact resistances r3 and r4 are generated in the measuring probes 31 and 32. In this state, current flows from the power supply 10 to the test board 200 via the measuring probes 21 and 22.

[0041] Next, the current measurement unit 20 measures the value of the current flowing through the test substrate 200. The voltage measurement unit 30 also measures the voltage between the measurement probes 31 and 32. In this case, since the internal resistance of the voltage measurement unit 30 is sufficiently large, almost no current flows from the power supply 10 through the path including the voltage measurement unit 30. Therefore, the voltage between the measurement probes 31 and 32 contains almost no voltage drop due to contact resistances r3 and r4. That is, the voltage between the measurement probes 31 and 32 is approximately equal to the voltage between the conductor layer 230 and the support substrate 210.

[0042] Based on the current and voltage measured by the current measuring unit 20 and the voltage measuring unit 30, respectively, the resistance value between the measuring probes 21 and 22 is calculated. As described above, the voltage value measured by the voltage measuring unit 30 hardly includes the voltage drop caused by the contact resistances r3 and r4, so the resistance value between the measuring probes 21 and 22 hardly includes the resistance values ​​of the contact resistances r1 to r4. In other words, the resistance value between the measuring probes 21 and 22 is approximately equal to the resistance value of the via 231.

[0043] According to this inspection method, the continuity tester 1 can detect minute changes in the resistance value of via 231. Therefore, the quality of via 231 is determined by comparing the calculated resistance value with a preset threshold value. For example, if the resistance value of via 231 is below the threshold value, via 231 is determined to be normal. On the other hand, if the resistance value of via 231 is greater than the threshold value, via 231 is determined to be abnormal.

[0044] (6) Modified methods of continuity testing In this embodiment, the measuring probe 21 branches into two contacts 21a and 21b, and the measuring probe 31 branches into two contacts 31a and 31b, but the embodiment is not limited to this. If the exposed portion of the support substrate 210 is smaller than the exposed portion of the conductor layer 230, the measuring probes 21 and 31 may not each branch into multiple contacts, and the measuring probes 22 and 32 may each branch into multiple contacts.

[0045] Figure 10 is a schematic diagram showing a first modified example of the continuity test method. As shown in the upper part of Figure 10, in this example, the measuring probe 22 includes two contacts 22a and 22b branched from the same node 22N. The measuring probe 32 includes two contacts 32a and 32b branched from the same node 32N. The spacing between contacts 22a and 22b, and the spacing between contacts 32a and 32b, is smaller than the maximum length of the exposed portion of the support substrate 210. The measuring probe 21 does not branch into multiple contacts. Similarly, the measuring probe 31 does not branch into multiple contacts.

[0046] The measuring probes 21 and 31 are in contact with the exposed portion of the conductor layer 230, and the measuring probes 22 and 32 are in contact with the exposed portion of the support substrate 210. However, if the area of ​​the exposed portion of the support substrate 210 is small, it becomes difficult to bring the measuring probes 22 and 32 into contact with the support substrate 210. Even in this case, the measuring probe 22 branches into contactors 22a and 22b, so the contactors 22a , 22bThe probability that at least one of the contacts will come into contact with the support substrate 210 is increased. Similarly, since the measuring probe 32 branches into contactors 32a and 32b, the probability that at least one of the contactors 32a and 32b will come into contact with the support substrate 210 is increased.

[0047] As shown in the lower part of Figure 10, the contacts 22a, 22b, 32a, and 32b may be arranged in a 2x2 grid. In the example in Figure 10, contacts 22a and 22b are arranged diagonally, and contacts 32a and 32b are arranged diagonally. With this arrangement, even if an overall misalignment occurs in the measuring probes 22 and 32, at least one of contacts 22a and 22b, and at least one of contacts 32a and 32b, can be more reliably brought into contact with the support substrate 210. The method for determining the quality of the vias 231 is the same as in the example in Figure 9.

[0048] If both the exposed portion of the support substrate 210 and the exposed portion of the conductor layer 230 are relatively small, each of the measuring probes 21, 22, 31, and 32 may be branched into multiple probes. Figure 11 is a schematic diagram showing a second modified example of the continuity test method. As shown in the upper part of Figure 11, in this example, the measuring probe 21 is branched into contacts 21a and 21b, and the measuring probe 22 is branched into contacts 22a and 22b. Also, the measuring probe 31 is branched into contacts 31a and 31b, and the measuring probe 32 is branched into contacts 32a and 32b.

[0049] As shown in the lower part of Figure 11, contacts 21a, 21b, 31a, and 31b may be arranged in a 2x2 grid, and contacts 22a, 22b, 32a, and 32b may be arranged in a 2x2 grid. In the example in Figure 11, contacts 21a and 21b are placed diagonally, and contacts 31a and 31b are placed diagonally. Also, contacts 22a and 22b are placed diagonally, and contacts 32a and 32b are placed diagonally.

[0050] The number of branches of the measuring probe is not limited to two. Figure 12 is a schematic diagram showing a third modified example of the continuity test method. As shown in the upper part of Figure 12, in this example, the measuring probe 21 branches into five contacts 21a to 21e, and the measuring probe 31 branches into four contacts 31a to 31d. The measuring probe 22 does not branch into multiple contacts. Also, the measuring probe 32 does not branch into multiple contacts.

[0051] As shown in the lower part of Figure 12, the contacts 21a-21e and 31a-31d may be arranged alternately and in a staggered pattern. In the example in Figure 12, the contacts 21a-21e and 31a-31d are arranged in a 3x3 grid. Specifically, four of the contacts 21a-21e are placed at the corners, and the remaining one is placed in the center. Each of the contacts 31a-31d is positioned so as to be sandwiched between any two of the contacts 21a-21e.

[0052] Figure 13 is a schematic diagram showing a fourth modification of the continuity test method. As shown in the upper part of Figure 13, in this example, the measuring probe 21 branches into three contacts 21a to 21c, and the measuring probe 22 branches into three contacts 22a to 22c. The measuring probe 31 branches into three contacts 31a to 31c, and the measuring probe 32 branches into three contacts 32a to 32c.

[0053] As shown in the lower part of Figure 13, the contacts 21a-21c and 31a-31c may be arranged alternately and in a staggered pattern. In the example in Figure 13, the contacts 21a-21c and 31a-31c are arranged in 2 rows and 3 columns. Specifically, one of the contacts 31a-31c is sandwiched between two of the contacts 21a-21c. The remaining contact 21a-21c is sandwiched between the remaining two of the contacts 31a-31c. The arrangement of the contacts 22a-22c and 32a-32c is the same as the arrangement of the contacts 21a-21c and 31a-31c.

[0054] Figure 14 is a schematic diagram showing a fifth modified example of the continuity test method. As shown in the upper part of Figure 14, in this example, the measuring probe 21 branches into five contacts 21a to 21e, and the measuring probe 31 branches into four contacts 31a to 31d. In addition, the measuring probe 22 branches into five contacts 22a to 22e, and the measuring probe 32 branches into four contacts 32a to 32d.

[0055] As shown in the lower part of Figure 14, the contacts 21a-21e and 31a-31d may be arranged alternately and in a staggered pattern. In the example in Figure 14, the contacts 21a-21e and 31a-31d are arranged in a 3x3 grid. Specifically, four of the contacts 21a-21e are placed at the corners, and the remaining one is placed in the center. Each of the contacts 31a-31d is positioned so as to be sandwiched between any two of the contacts 21a-21e. The arrangement of the contacts 22a-22e and 32a-32d is the same as that of the contacts 21a-21e and 31a-31d.

[0056] (7) Method for manufacturing a suspension substrate A method for manufacturing the suspension substrate 100 will now be described. In this example, multiple aggregate sheets 500 are manufactured on a long support substrate using a roll-to-roll method. Multiple suspension substrates 100 are formed on each aggregate sheet 500. Figures 15 to 19 are cross-sectional views showing an example of a method for manufacturing the aggregate sheet 500 according to one embodiment of the present invention. The upper figures in Figures 15 to 19 correspond to the cross-section along line BB in Figure 5. The lower figures in Figures 15 to 19 correspond to the cross-section along line CC in Figure 6.

[0057] First, as shown in Figure 15, a base insulating layer 540 made of polyimide is formed on a long support substrate 530 made of stainless steel. A two-layer substrate having a laminated structure of the support substrate 530 and the base insulating layer 540 may also be used. The material of the support substrate 530 is not limited to stainless steel; other metal materials such as aluminum (Al) may also be used.

[0058] The thickness of the support substrate 530 is, for example, 10 μm to 30 μm, and preferably 12 μm to 25 μm. The material of the base insulating layer 540 is not limited to polyimide; other resin materials such as epoxy may be used. The thickness of the base insulating layer 540 is, for example, 1 μm to 30 μm, and preferably 3 μm to 20 μm.

[0059] Next, as shown in Figure 16, the base insulating layer 540 is etched to form the base insulating layer 170 for the suspension substrate 100 and the base insulating layer 220 for the inspection substrate 200. At the same time, through holes 171 and 172 are formed in the base insulating layer 170 at the intersection regions 113 and 114 in Figure 3. An opening 221 and through holes 222 are also formed in the base insulating layer 220. The minimum diameter of the through holes 171 and 172 is, for example, 10 μm or more and 200 μm or less, and preferably 20 μm or more and 100 μm or less.

[0060] Next, as shown in Figure 17, the writing wiring patterns 120, 130, reading wiring patterns 140, 150, and electrode pads 161-168, all made of copper, are formed on the base insulating layer 170 by electroplating or the like. In addition, a conductor layer 230 made of copper is formed on the base insulating layer 220. In Figure 17, only the lines 123, 125 and connection parts 126, 127 of the writing wiring pattern 120, and the line 135 of the writing wiring pattern 130 are shown.

[0061] The portion of the connection 126 within the through-hole 171 becomes via 128, and the portion of the connection 127 within the through-hole 172 becomes via 129. Also, the portion of the conductor layer 230 within the through-hole 222 becomes via 231. The writing wiring patterns 120, 130 and the reading wiring patterns 140, 150, as well as the conductor layer 230, may be formed using an additive method, a semi-additive method, or other methods such as a subtractive method.

[0062] The materials for the writing wiring patterns 120, 130, reading wiring patterns 140, 150, electrode pads 161-168, and conductor layer 230 are not limited to copper; other metals such as gold (Au) or aluminum, or alloys such as copper alloys or aluminum alloys may be used. The thickness of the writing wiring patterns 120, 130 and reading wiring patterns 140, 150 is, for example, 3 μm to 25 μm, and preferably 4 μm to 20 μm. The width of the writing wiring patterns 120, 130 and reading wiring patterns 140, 150 is, for example, 6 μm to 200 μm, and preferably 8 μm to 150 μm.

[0063] Subsequently, as shown in Figure 18, a cover insulating layer 180 made of polyimide is formed on the base insulating layer 170 so as to cover the writing wiring patterns 120, 130 and the reading wiring patterns 140, 150. At the same time, a cover insulating layer 240 made of polyimide is formed on the base insulating layer 220 so as to cover the vias 231 of the conductor layer 230. The material of the cover insulating layers 180 and 240 is not limited to polyimide, and other insulating materials such as epoxy may be used. The thickness of the cover insulating layers 180 and 240 is, for example, 1 μm or more and 30 μm or less, and preferably 3 μm or more and 10 μm or less.

[0064] Furthermore, a plating layer made of, for example, gold (Au) may be formed on the surface of the conductor layer 230, except for the via 231 portion of the conductor layer 230. Also, on the surface of the electrode pads 161-168 in Figure 2 formed on the surface of the conductive layer 230 A plating layer similar to the existing plating layer may be formed.

[0065] Subsequently, by etching the support substrate 530, for example, the separation groove 526 shown in Figure 1 is formed on the support substrate 530, and in the intersection regions 113 and 114 shown in Figure 3, 5 An annular opening 115 is formed. At the same time, an opening 111 as shown in Figure 2 is formed in the support substrate 530. In addition, the individual aggregate sheets 500 are separated by cutting the elongated support substrate 530 at regular intervals.

[0066] As a result, as shown in Figure 19, a support substrate 110 for the suspension substrate 100, a support substrate 210 for the inspection substrate 200, the support frame 510 and connecting portion 520 shown in Figure 1 are formed. In addition, an annular opening 115 is formed in the support substrate 110, and a region 116 separated from other regions is formed in the support substrate 110. The area of ​​region 116 is, for example, 1800 μm². 2 More than 180000μm 2 The following is true, 3200 μm 2 More than 80000μm 2 The following is preferable:

[0067] Through the above process, an assembly sheet 500 including multiple suspension substrates 100, multiple test substrates 200, and a support frame 510 is completed. After the completion of the suspension substrates 100, a continuity test is performed on the vias 231 shown in Figures 9 to 14. In addition, a continuity test is performed between electrode pads 161 and 165, between electrode pads 162 and 166, between electrode pads 163 and 167, and between electrode pads 164 and 168.

[0068] The continuity test between electrode pads 161 and 165 is performed by bringing the measuring probes 21 and 31 of the continuity tester 1 shown in Figures 9 to 14 into contact with electrode pad 161, and the measuring probes 22 and 32 into contact with electrode pad 165. The same procedure is followed for continuity tests between electrode pads 162 and 166, between electrode pads 163 and 167, and between electrode pads 164 and 168.

[0069] If the continuity tests indicate that via 231, writing wiring patterns 120, 130, and reading wiring patterns 140, 150 are normal, the suspension board 100 is determined to be normal. If all suspension boards 100 are determined to be normal, the multiple connecting parts 520 are cut, separating each suspension board 100 from the support frame 510. On the other hand, if even one suspension board 100 is determined to be abnormal, the assembly sheet 500 containing that suspension board 100 is discarded.

[0070] (8) Other examples of continuity testers In the manufacturing process of the aggregate sheet 500 described above, continuity testing between electrode pads 161-164 and 165-168 is performed using the continuity tester 1 shown in Figure 8, but the embodiment is not limited to this. If the area of ​​electrode pads 161-168 is relatively large, continuity testing between electrode pads 161-164 and 165-168 may be performed using a different continuity tester than the continuity tester 1.

[0071] Figure 20 is a schematic diagram showing the configuration of a continuity tester in another example. As shown in Figure 20, the continuity tester 2 includes a power supply 40, a current measuring unit 50, a voltage measuring unit 60, and measuring probes 51, 52, 61, and 62. Unlike the measuring probes 21, 22, 31, and 32 of the continuity tester 1, each of the measuring probes 51, 52, 61, and 62 does not branch into multiple contacts.

[0072] In this example, the power supply 40 is an AC power supply, but it may also be a DC power supply. One terminal of the power supply 40 is connected to the measuring probe 51 via the current measuring unit 50. The other terminal of the power supply 40 is connected to the measuring probe 52. One terminal of the voltage measuring unit 60 is connected to the measuring probe 61. The other terminal of the voltage measuring unit 60 is connected to the measuring probe 62.

[0073] In the continuity test between electrode pads 161 and 165, measuring probes 51 and 61 are in contact with electrode pad 161, and measuring probes 52 and 62 are in contact with electrode pad 165 The electrodes are brought into contact with each other. In this state, current flows from the power supply 40 to the suspension substrate 100 via the measuring probes 51 and 52. This allows the resistance value between electrode pads 161 and 165 to be measured with little influence from contact resistance, similar to the continuity tester 1. The same applies to continuity testing between electrode pads 162-164 and 166-168.

[0074] (9) Jig A continuity test may be performed on a predetermined number of suspension boards 100 at once using a jig that holds a continuity tester 1 and multiple continuity testers 2. Figure 21 is a schematic top view showing an example of the jig. Figure 22 is a partially enlarged cross-sectional view of the jig 300 of Figure 21. Below, an example of performing a continuity test on three suspension boards 100 at once using the jig 300 of Figures 21 and 22 will be described.

[0075] As shown in Figures 21 and 22, the jig 300 includes stacked plates 310, 320, and 330. In Figure 21, only plate 310 is shown. Plate 320 is positioned between plate 310 and plate 330. Each of plates 310, 320, and 330 has a rectangular shape. In the jig 300, the direction in which one pair of sides of plates 310, 320, and 330 extend is defined as the x-direction, and the direction in which the other pair of sides extend is defined as the y-direction. Plate 310 is movable up and down relative to plates 320 and 330 by an actuator (not shown).

[0076] As shown in Figure 21, the plate 310 holds the measuring probes 21, 22, 31, and 32 of the continuity tester 1 (Figure 8), as well as the measuring probes 51, 52, 61, and 62 of the multiple continuity testers 2 (Figure 20). In this example, the contacts 21a and 21b of the measuring probe 21, the contacts 31a and 31b of the measuring probe 31, and the measuring probes 22 and 32 are held by the plate 310. The contacts 21a, 21b, 31a, and 31b and the measuring probes 22 and 32 are located near the center of the fixture 300 in the x-direction.

[0077] Furthermore, four measuring probes 51, 52, 61, and 62 are required to perform a continuity test on the electrode pads 161-164 and 165-168 simultaneously for each suspension substrate 100. Therefore, when performing a continuity test on three suspension substrates 100 simultaneously, twelve measuring probes 51, 52, 61, and 62 are held on the plate 310. In the following description, the contacts 21a, 21b, 31a, and 31b of the measuring probes 21 and 31 held on the plate 310, and the measuring probes 22, 32, 51, 52, 61, and 62 are simply referred to as probes.

[0078] As shown in Figure 22, the plate 320 has multiple through holes 321, each corresponding to one of the probes. Similarly, the plate 330 has multiple through holes 331, each corresponding to one of the probes. In Figure 22, only the through holes 321 and 331 corresponding to the measuring probe 51 are shown. Each probe held in the plate 310 is inserted through the corresponding through hole 321 or 331. The tip of each probe protrudes from the plate 330.

[0079] The jig 300 is positioned above the assembly sheet 500 with its x and y directions facing the X and Y directions of the assembly sheet 500 in Figure 1. During the continuity test, the jig 300 is moved so that it overlaps with a predetermined number (3 in this example) of suspension substrates 100 that are to be tested. At this time, the jig 300 is positioned so that its central portion in the x direction overlaps with the central portion in the x direction of the area containing the predetermined number of suspension substrates 100.

[0080] In this state, as the plate 310 moves up and down, each probe comes into contact with the corresponding support substrate 210, conductor layer 230, or electrode pads 161-168. Furthermore, by aligning the jig 300 as described above, even if the support frame 510 of the aggregate sheet 500 flexes, the contacts 21a and 21b of the measuring probe 21 and the contacts 31a and 31b of the measuring probe 31 can be reliably brought into contact with the conductor layer 230.

[0081] Subsequently, the power supply 10 of the continuity tester 1 and the power supplies 40 of the multiple continuity testers 2 are turned on for a predetermined amount of time in a set sequence. This measures the resistance between predetermined parts of the suspension board 100 or the test board 200. As a result, a continuity test is performed on a predetermined number of suspension boards 100 all at once. The order in which the power supply 10 and the multiple power supplies 40 are turned on is not limited.

[0082] After the continuity test is completed for a predetermined number of suspension boards 100, the plate 310 moves up and down, so that each probe is separated from the corresponding support board 210, conductor layer 230, or electrode pads 161-168. Then the jig 300 is moved so that it overlaps with the next predetermined number of suspension boards 100, and the same continuity test is performed.

[0083] The above operation is repeated until the continuity test for all suspension boards 100 in the assembly sheet 500 is completed. If any one of the suspension boards 100 is determined to be abnormal during the continuity test, the continuity test for the assembly sheet 500 containing that suspension board 100 may be terminated.

[0084] (10) Effects In the continuity testing method for the suspension substrate 100 according to this embodiment, the measuring probe 21 branches into a plurality of contacts 21a, 21b, 21c, ... With this configuration, even if the measuring probe 21 is misaligned or some of the contacts 21a, 21b, 21c, ... are damaged when the measuring probe 21 is brought into contact with the conductor layer 230, at least one of the contacts 21a, 21b, 21c, ... can be easily brought into contact with the conductor layer 230.

[0085] This method for testing the continuity of the suspension substrate 100 reduces the likelihood of the suspension substrate 100 being deemed defective due to the measuring probe 21 not making proper contact with the conductor layer 230. As a result, the accuracy of the continuity test of the suspension substrate 100 can be improved.

[0086] In particular, if the area of ​​the conductor layer 230 that the measuring probe 21 can contact is small, it becomes difficult to bring the measuring probe 21 into contact with the conductor layer 230. Even in this case, since the measuring probe 21 branches into multiple contacts 21a, 21b, 21c, ..., the probability that at least one of the contacts 21a, 21b, 21c, ... will contact the conductor layer 230 is improved. This improves the accuracy of the continuity test of the suspension substrate 100.

[0087] On the other hand, the measuring probe 22 may branch into multiple contacts 22a, 22b, 22c, ... With this configuration, even if the measuring probe 22 is misaligned when it is brought into contact with the support substrate 210, or if some of the contacts 22a, 22b, 22c, ... are damaged, the likelihood of the suspension substrate 100 being determined to be defective is reduced.

[0088] Furthermore, the measuring probe 31 may be further brought into contact with the conductor layer 230, and the measuring probe 32 may be further brought into contact with the support substrate 210. In this case, it is possible to measure the resistance value between the conductor layer 230 and the support substrate 210 without being affected by contact resistance. This can further improve the accuracy of the continuity test of the suspension substrate 100.

[0089] Here, the measuring probe 31 may branch into multiple contacts 31a, 31b, 31c, ... With this configuration, even if the measuring probe 31 is misaligned when it is brought into contact with the conductor layer 230, or if some of the contacts 31a, 31b, 31c, ... are damaged, the likelihood of the suspension substrate 100 being determined to be defective is reduced.

[0090] Alternatively, the measuring probe 32 may branch into multiple contacts 32a, 32b, 32c, ... With this configuration, even if the measuring probe 32 is misaligned when it is brought into contact with the support substrate 210, or if some of the contacts 32a, 32b, 32c, ... are damaged, the likelihood of the suspension substrate 100 being determined to be defective is reduced.

[0091] The measuring probe 21 may include two contacts 21a and 21b, and the measuring probe 31 may also include two contacts 31a and 31b. In this case, it is preferable that the contacts 21a, 21b, 31a, and 31b are arranged in a 2x2 configuration, with contact 21a and contact 21b positioned diagonally opposite each other, and contact 31a and contact 31b positioned diagonally opposite each other.

[0092] Alternatively, the measuring probe 21 may include three or more contacts 21a, 21b, 21c, ... and the measuring probe 31 may include three or more contacts 31a, 31b, 31c, ... In this case, it is preferable that the contacts 21a, 21b, 21c, ... and the contacts 31a, 31b, 31c, ... are arranged alternately and in a staggered pattern.

[0093] With these arrangements, even if there is an overall misalignment of the measuring probes 21 and 31, at least one of the contacts 21a, 21b, 21c, ... and at least one of the contacts 31a, 31b, 31c, ... can be more reliably brought into contact with the conductor layer 230. This improves the accuracy of the continuity test of the suspension substrate 100.

[0094] Similarly, the measuring probe 22 may include two contacts 22a and 22b, and the measuring probe 32 may include two contacts 32a and 32b. In this case, it is preferable that the contacts 22a, 22b, 32a, and 32b are arranged in a 2x2 configuration, with contacts 22a and 22b positioned diagonally opposite each other, and contacts 32a and 32b positioned diagonally opposite each other.

[0095] Alternatively, the measuring probe 22 may include three or more contacts 22a, 22b, 22c, ... and the measuring probe 32 may include three or more contacts 32a, 32b, 32c, ... In this case, it is preferable that the contacts 22a, 22b, 22c, ... and the contacts 32a, 32b, 32c, ... are arranged alternately and in a staggered pattern.

[0096] With these arrangements, even if there is an overall misalignment of the measuring probes 22 and 32, at least one of the contacts 22a, 22b, 22c, ... and at least one of the contacts 32a, 32b, 32c, ... can be more reliably brought into contact with the support substrate 210. This improves the accuracy of the continuity test of the suspension substrate 100.

[0097] (11) Other embodiments (a) In the above embodiment, the continuity tester 1 includes four measuring probes 21, 22, 31, and 32, but the embodiment is not limited thereto. The differences between the continuity tester 1 in other embodiments and the continuity tester 1 in Figure 8 will be explained below. Figure 23 is a diagram showing an example of the continuity tester 1 in another embodiment. The upper part of Figure 23 shows a schematic diagram of the continuity tester 1. The lower part of Figure 23 shows an example of the arrangement of the measuring probes 11 and 12 (described later) of the continuity tester 1 in the upper part. The same applies to Figures 24 and 25, which will be described later.

[0098] As shown in Figure 23, in this example, the continuity tester 1 includes two measuring probes 11 and 12 instead of four measuring probes 21, 22, 31, and 32. One terminal of the power supply 10 is connected to the measuring probe 11 via the current measuring unit 20. The other terminal of the power supply 10 is connected to the measuring probe 12. The voltage measuring unit 30 is connected in parallel to the series-connected power supply 10 and current measuring unit 20. The measuring probe 11 includes two contacts 11a and 11b branched from the same node 11N.

[0099] The measuring probe 11 is in contact with the exposed portion of the conductor layer 230, and the measuring probe 12 is in contact with the exposed portion of the support substrate 210. However, if the area of ​​the exposed portion of the conductor layer 230 is small, it becomes difficult to bring the measuring probe 11 into contact with the conductor layer 230. Even in this case, since the measuring probe 11 branches into contactors 11a and 11b, the probability that at least one of the contactors 11a and 11b will come into contact with the conductor layer 230 is increased.

[0100] In the example shown in Figure 23, the measuring probe 12 does not branch into multiple contacts, but the embodiment is not limited to this. Figure 24 shows another example of the continuity tester 1 in another embodiment. As shown in Figure 24, in this example, similar to the measuring probe 11, the measuring probe 12 also includes two contacts 12a and 12b branched from the same node 12N. With this configuration, even when the exposed area of ​​the support substrate 210 is small, the probability that at least one of the contacts 12a and 12b will contact the conductor layer 230 is improved.

[0101] Figure 25 shows yet another example of the continuity tester 1 in another embodiment. As shown in Figure 25, in this example the measuring probe 11 includes three branched contacts 11a to 11c. The measuring probe 12 includes four branched contacts 12a to 12d.

[0102] As the measuring probes 11 and 12 in Figures 23 to 25 come into contact with the conductive layer 230 and the support substrate 210, respectively, contact resistances r5 and r6 are generated in the measuring probes 11 and 12. In this state, current flows from the power supply 10 to the test substrate 200 via the measuring probes 11 and 12. Next, the current measurement unit 20 measures the value of the current flowing through the test substrate 200. In addition, the voltage measurement unit 30 measures the voltage between the measuring probes 11 and 12.

[0103] Based on the current and voltage measured by the current measuring unit 20 and the voltage measuring unit 30, respectively, the resistance value between the measuring probes 11 and 12 is calculated. The resistance value between the measuring probes 11 and 12 includes the contact resistance values ​​r5 and r6. However, if the contact resistance values ​​r5 and r6 are relatively small, the quality of the via 231 can be determined by comparing the measured resistance value with a preset threshold value.

[0104] (b) The continuity tester 2 includes four measuring probes 51, 52, 61, and 62, but the embodiment is not limited thereto. Unlike between electrode pads 161 and 165 or between electrode pads 162 and 166, the lines connecting electrode pads 163 and 167 or between electrode pads 164 and 168 do not branch into multiple lines. Therefore, measuring the resistance value between electrode pads 163 and 167 or between electrode pads 164 and 168 does not require the same level of precision as measuring the resistance value between electrode pads 161 and 165 or between electrode pads 162 and 166.

[0105] Therefore, when performing a continuity test between electrode pads 163 and 167 or between electrode pads 164 and 168, the continuity tester 2 does not need to include the four measuring probes 51, 52, 61, and 62. Below, the differences between the continuity tester 2 in other embodiments and the continuity tester 1 in Figure 20 will be explained. Figure 26 is a diagram showing an example of the continuity tester 2 in another embodiment.

[0106] As shown in Figure 26, in this example, the continuity tester 2 includes two measuring probes 41 and 42 instead of four measuring probes 51, 52, 61, and 62. One terminal of the power supply 40 is connected to measuring probe 41 via the current measuring unit 50. The other terminal of the power supply 40 is connected to measuring probe 42. The voltage measuring unit 60 is connected in parallel to the series-connected power supply 40 and current measuring unit 50.

[0107] In the continuity test between electrode pads 163 and 167, measuring probe 41 is in contact with electrode pad 163, and measuring probe 42 is in contact with electrode pad 167. In this state, current flows from the power supply 40 to the suspension board 100 via measuring probes 41 and 42. This allows the resistance value between measuring probes 41 and 42 to be calculated. The same procedure is followed for the continuity test between electrode pads 164 and 168.

[0108] (c) In the above embodiment, a plurality of inspection substrates 200 are provided on the assembly sheet 500 so that each corresponds to a plurality of suspension substrates 100 in a one-to-one relationship, but the embodiment is not limited thereto. A plurality of inspection substrates 200 may be provided on the assembly sheet 500 so that one inspection substrate 200 corresponds to a predetermined number of suspension substrates 100.

[0109] On the other hand, multiple inspection boards 200 may be provided on the assembly sheet 500 such that a predetermined number of inspection boards 200 correspond to one suspension board 100. In this case, the dimensions of the vias 231 on the predetermined number of inspection boards 200 may differ from one another.

[0110] Furthermore, when using the jig 300 shown in Figure 21, a continuity test is performed on the vias 231 of one test board 200 corresponding to a predetermined number of suspension boards 100. The test result of one via 231 is then used as the test result for the vias 128 and 129 of the predetermined number of suspension boards 100. However, the embodiment is not limited to this. Even when using the jig 300, a continuity test may be performed on the vias 231 of the test board 200 corresponding to each of the predetermined number of suspension boards 100. In this case, more accurate test results for the vias 128 and 129 of each suspension board 100 can be obtained.

[0111] (12) Examples In the following Examples 1 to 3, a continuity tester 1 was prepared in which the measuring probe 21 branched into three contacts 21a to 21c, and the measuring probe 31 branched into three contacts 31a to 31c. The measuring probes 22 and 32 did not branch into multiple contacts. In Reference Example 1, the continuity tester 2 shown in Figure 20 was prepared. Using these continuity testers 1 and 2, continuity tests were performed on each of the test substrates 200 having vias 231 with diameters of 30 μm, 40 μm, and 60 μm.

[0112] Figures 27 and 28 show the arrangement of the measurement probes 21, 22, 31, 32, 51, 52, 61, and 62 in Examples 1 to 3 and Reference Example 1. As shown in Figure 27, in Example 1, all six contacts 21a to 21c and 31a to 31c were in contact with the conductor layer 230, and the measurement probes 22 and 32 were in contact with the support substrate 210. In Example 2, of the six contacts 21a to 21c and 31a to 31c, only four contacts 21a, 21c, 31a, and 31b were in contact with the conductor layer 230, and the measurement probes 22 and 32 were in contact with the support substrate 210.

[0113] As shown in Figure 28, in Example 3, of the six contacts 21a-21c and 31a-31c, only two contacts 21a and 31b were in contact with the conductor layer 230, and the measuring probes 22 and 32 were in contact with the support substrate 210. In Reference Example 1, the measuring probes 51 and 61 were in contact with the conductor layer 230, and the measuring probes 52 and 62 were in contact with the support substrate 210.

[0114] Figure 29 shows the results of the continuity test in Examples 1-3 and Reference Example 1. As shown in Figure 29, when the diameter of the vias 231 was the same, the measured resistance values ​​were approximately the same among Examples 1-3 and Reference Example 1. That is, it was confirmed that a substantially accurate resistance value can be measured as long as at least one of the three contacts 21a-21c and at least one of the contacts 31a-31c are in contact with the conductor layer 230. Therefore, it was confirmed that it is possible to determine whether the vias 231 are normal or not by preparing a predetermined threshold value, regardless of the number of contacts 21a-21c and 31a-31c.

[0115] In Example 4 below, the same continuity tester 1 as in Examples 1-3 was used to evaluate the percentage of defective aggregate sheets 500. Similarly, in Reference Example 2, the same continuity tester 2 as in Reference Example 1 was used to evaluate the percentage of defective aggregate sheets 500.

[0116] Figure 30 shows the percentage of defective products in Example 4 and Reference Example 2. The vertical axis of Figure 30 represents the number of assembled sheets 500. The horizontal axis of Figure 30 represents the manufacturing lot number of the assembled sheets 500. The bar graph with a hatching pattern shows the number of assembled sheets 500 inspected, and the bar graph with a dot pattern shows the number of assembled sheets 500 that were determined to be defective.

[0117] As shown in Figure 30, in Example 4, there were no assembled sheets 500 that were determined to be defective. Therefore, although it is unknown how many of the contacts 21a-21c and 31a-31c were in contact with the conductor layer 230, it is presumed that at least one of the contacts 21a-21c and at least one of the contacts 31a-31c were in contact with the conductor layer 230.

[0118] On the other hand, in Reference Example 2, nearly half of the aggregate sheets 500 were determined to be defective. In this regard, since the defect rate in Example 4 was 0, it is highly probable that in Reference Example 2, the aggregate sheets 500 that were determined to be defective were not actually defective, but rather that the measurement probes 51 and 61 were not in contact with the conductor layer 230 due to misalignment. Thus, it is estimated that the cause of the majority of aggregate sheets 500 being determined to be defective is not due to wire breakage or the like, but rather to misalignment of the contact position of the measurement probes.

[0119] (13) Correspondence between each component of the claim and each part of the embodiment The following describes examples of the correspondence between each component of the claims and each part of the embodiments, but the present invention is not limited to the following examples. Various other elements having the configuration or function described in the claims can also be used as each component of the claims.

[0120] One of the electrode pads 161-164 and the other of the electrode pads 165-168, or the other of the support substrate 210 and the conductor layer 230, is an example of a first terminal portion. The other of the electrode pads 161-164 and the other of the electrode pads 165-168, or the other of the support substrate 210 and the conductor layer 230, is an example of a second terminal portion.

[0121] The suspension substrate 100 is an example of a wiring circuit board, the support substrate 110 or support substrate 210 is an example of a metal support substrate, and the base insulating layer 170 or base insulating layer 220 is an example of an insulating layer. The writing wiring patterns 120, 130, the reading wiring patterns 140, 150 or the conductor layer 230 are examples of conductor layers, and the vias 128, 129 or via 231 are examples of vias.

[0122] One of the measurement probes 11, 12 or one of the measurement probes 21, 22 is an example of the first measurement probe. The other of the measurement probes 11, 12 or the other of the measurement probes 21, 22 is an example of the second measurement probe. One of the measurement probes 31, 32 is an example of the third measurement probe. The other of the measurement probes 31, 32 is an example of the fourth measurement probe.

[0123] One of contacts 11a-11c and one of contacts 12a-12d, or one of contacts 21a-21e and one of contacts 22a-22e, is an example of multiple contacts of the first measuring probe. The other of contacts 11a-11c and one of contacts 12a-12d, or the other of contacts 21a-21e and one of contacts 22a-22e, is an example of multiple contacts of the second measuring probe. One of contacts 31a-31d and one of contacts 32a-32d is the 3 This is an example of multiple contacts on a measuring probe.

[0124] Contactor 21a or contactor 22a is an example of a first contactor. Contactor 21b or contactor 22b is an example of a second contactor. Contactor 31a or contactor 32a is an example of a third contactor. Contactor 31b or contactor 32b is an example of a fourth contactor.

[0125] (14) Summary of Embodiments

[0126] (Paragraph 1) The method for testing the continuity of a wiring circuit board relating to Paragraph 1 is: A method for testing the continuity of a wiring circuit board having a first terminal portion and a second terminal portion, The first measuring probe, which is branched into multiple contacts, is brought into contact with the first terminal portion, This includes bringing the second measuring probe into contact with the second terminal portion.

[0127] According to this continuity test method for wiring circuit boards, even if the first measuring probe is misaligned or some of the contacts are damaged when the first measuring probe is brought into contact with the first terminal, at least one contact can be easily made to contact the first terminal. As a result, the number of cases in which the wiring circuit board is judged to be defective due to the first measuring probe not making proper contact with the first terminal is reduced. Consequently, the accuracy of the continuity test of the wiring circuit board can be improved.

[0128] (Article 2) In the continuity test method for a wiring circuit board described in Article 1, The first terminal portion has a first region to which the first measuring probe can make contact, The second terminal portion has a second area to which the second measuring probe can make contact, The area of ​​the first region may be smaller than the area of ​​the second region.

[0129] If the area of ​​the first measuring probe that can reach the first terminal is small, it becomes difficult to bring the first measuring probe into contact with the first terminal. Even in this case, since the first measuring probe branches into multiple contacts, the probability that at least one contact will make contact with the first terminal is improved. This improves the accuracy of continuity testing of the wiring circuit board.

[0130] (Article 3) In the continuity test method for a wiring circuit board described in Article 1 or Article 2, Bringing the second measuring probe into contact with the second terminal portion may include bringing the second measuring probe, which has been branched into multiple contacts, into contact with the second terminal portion.

[0131] This method ensures that even if the second measuring probe is misaligned or some of its contacts are damaged when it is brought into contact with the second terminal, at least one contact can still be easily made to contact the second terminal. This reduces the likelihood of a wiring circuit board being incorrectly identified as defective due to improper contact between the second measuring probe and the second terminal. As a result, the accuracy of the continuity test of the wiring circuit board can be improved.

[0132] (Article 4) In the continuity test method for a wiring circuit board described in any one of Articles 1 to 3, The aforementioned wiring circuit board has a laminated metal support substrate, an insulating layer, and a conductor layer. The conductor layer and the metal support substrate are electrically connected via vias. The first terminal portion is formed on either the conductor layer or the metal support substrate. The second terminal portion may be formed on the other of the conductor layer and the metal support substrate.

[0133] In this case, a continuity test can be performed between the first terminal and the second terminal, which are electrically connected via a via.

[0134] (Article 5) The continuity test method for a wiring circuit board described in any one of Articles 1 to 4 is: By bringing the third measuring probe into contact with the first terminal portion, This may further include bringing a fourth measuring probe into contact with the second terminal portion.

[0135] In this case, the accuracy of the continuity test of the wiring circuit board can be further improved.

[0136] (Article 6) In the continuity test method for a wiring circuit board described in Article 5, Bringing the third measuring probe into contact with the first terminal portion may include bringing the third measuring probe, which has been branched into a plurality of contacts, into contact with the first terminal portion.

[0137] According to this method, even if the third measuring probe becomes misaligned or some of the contacts are damaged when bringing the third measuring probe into contact with the first terminal, at least one contact can be easily made to contact the third terminal. This reduces the likelihood of a wiring circuit board being judged as defective due to the third measuring probe not making proper contact with the first terminal. As a result, the accuracy of the continuity test of the wiring circuit board can be further improved.

[0138] (Section 7) In the continuity test method for wiring circuit boards described in Section 6, The multiple contacts of the first measuring probe and the multiple contacts of the third measuring probe may be arranged alternately and in a staggered pattern.

[0139] This method allows for more reliable contact between at least one contact of the first measuring probe and at least one contact of the third measuring probe and the first terminal portion, even if an overall misalignment occurs in the first and third measuring probes. This improves the accuracy of continuity testing of wiring circuit boards.

[0140] (Clause 8) In the continuity test method for wiring circuit boards described in paragraph 7, The plurality of contacts of the first measuring probe include a first contact and a second contact, The plurality of contacts of the third measuring probe include a third contact and a fourth contact, The first contact, the second contact, the third contact, and the fourth contact may be arranged in a 2x2 configuration, with the first contact and the second contact positioned diagonally opposite each other, and the third contact and the fourth contact positioned diagonally opposite each other.

[0141] This method allows for more reliable contact between at least one of the first and second contacts, and at least one of the third and fourth contacts, with the first terminal, even if an overall misalignment occurs in the first and third measuring probes. This improves the accuracy of continuity testing of wiring circuit boards.

[0142] (Paragraph 9) The method for manufacturing a wiring circuit board relating to Paragraph 9 is: To form a first terminal portion and a second terminal portion, By bringing the first measuring probe, which is branched into multiple contacts, into contact with the first terminal portion formed thereon, This includes bringing a second measuring probe into contact with the formed second terminal portion.

[0143] According to this method for manufacturing a wiring circuit board, a first terminal portion and a second terminal portion are formed. A continuity test is then performed between the formed first terminal portion and the second terminal portion. In this continuity test, even if the first measuring probe is misaligned or some of the contacts are damaged when the first measuring probe is brought into contact with the first terminal portion, at least one contact can be easily brought into contact with the first terminal portion. This reduces the likelihood of the wiring circuit board being judged as defective due to the first measuring probe not making proper contact with the first terminal portion. [Explanation of Symbols]

[0144] 1,2…Continuity tester, 10,40…Power supply, 11,12,21,22,31,32,41,42,51,52,61,62…Measurement probe, 11N,12N,21N,22N,31N,32N…Node, 20,50…Current measurement section, 11a~11c,12a~12d,21a~21e,22a~22e,31a~31d,32a~32d…Contact, 30,60…Voltage measurement section, 100…Suspension board, 110,210,530…Support board, 111,115,221,241…Opening, 112…Tang section, 113,114…Crossing region, 116…Region, 120,130…Writing wiring pattern N, 121~125, 131~135…Train line, 126, 127…Connection part, 128, 129, 231…Via, 140, 150…Readable wiring pattern, 161~168…Electrode pad, 170, 220, 540…Base insulating layer, 171, 172, 222, 321, 331…Through hole, 180, 240…Cover insulating layer, 200…Inspection substrate, 230…Conductor layer, 300…Jig, 310, 320, 330…Plate, 500…Assembly sheet, 510…Support frame, 511, 512…Side frame, 513~518…End frame, 520…Connecting part, 521~525…Rectangular area, 526…Separation groove, r1~r6…Contact resistance

Claims

1. A method for testing the continuity of a wiring circuit board having a first terminal portion and a second terminal portion, The first measuring probe, which is branched into multiple contacts, is brought into contact with the first terminal portion, This includes bringing the second measuring probe into contact with the second terminal portion. A method for testing the continuity of a wiring circuit board, wherein the multiple contacts of the first measuring probe are spaced apart from each other while maintaining their relative positional relationship.

2. The first terminal portion has a first region to which the first measuring probe can make contact, The second terminal portion has a second region to which the second measuring probe can make contact, The method for testing the continuity of a wiring circuit board according to claim 1, wherein the area of ​​the first region is smaller than the area of ​​the second region.

3. The method for testing the continuity of a wiring circuit board according to claim 1 or 2, wherein bringing the second measuring probe into contact with the second terminal portion includes bringing the second measuring probe, which is branched into a plurality of contacts, into contact with the second terminal portion.

4. The aforementioned wiring circuit board has a laminated metal support substrate, an insulating layer, and a conductor layer. The conductor layer and the metal support substrate are electrically connected via vias. The first terminal portion is formed on either the conductor layer or the metal support substrate. The method for testing the continuity of a wiring circuit board according to claim 1 or 2, wherein the second terminal portion is formed on the other of the conductor layer and the metal support substrate.

5. By bringing the third measuring probe into contact with the first terminal portion, The method for testing the continuity of a wiring circuit board according to claim 1 or 2, further comprising bringing a fourth measuring probe into contact with the second terminal portion.

6. The method for testing the continuity of a wiring circuit board according to claim 5, wherein bringing the third measuring probe into contact with the first terminal portion includes bringing the third measuring probe, which is branched into a plurality of contacts, into contact with the first terminal portion.

7. The method for testing the continuity of a wiring circuit board according to claim 6, wherein the plurality of contacts of the first measuring probe and the plurality of contacts of the third measuring probe are arranged alternately and in a staggered pattern.

8. The plurality of contacts of the first measuring probe include a first contact and a second contact, The plurality of contacts of the third measuring probe include a third contact and a fourth contact, The method for testing the continuity of a wiring circuit board according to claim 7, wherein the first contact, the second contact, the third contact, and the fourth contact are arranged in a 2x2 configuration, with the first contact and the second contact positioned diagonally opposite each other, and the third contact and the fourth contact positioned diagonally opposite each other.

9. To form a first terminal portion and a second terminal portion, The first measuring probe, which is branched into multiple contacts, is brought into contact with the first terminal portion that is formed therein. This includes bringing a second measuring probe into contact with the second terminal portion formed thereon. A method for manufacturing a wiring circuit board, wherein the multiple contacts of the first measuring probe are spaced apart from each other while maintaining their relative positional relationship.

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