公开(公告)号：US07832098B2

公开(公告)日：2010-11-16

申请号：US12098582

申请日：2008-04-07

Applicant: Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

Inventor： Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

IPC: H01K3/10

CPC classification number: H05K3/4652 ,  B23K26/389 ,  H01L2224/16225 ,  H01L2924/15174 ,  H01L2924/15311 ,  H05K1/0201 ,  H05K3/0032 ,  H05K3/0035 ,  H05K3/0038 ,  H05K3/0055 ,  H05K3/0094 ,  H05K3/108 ,  H05K3/28 ,  H05K3/381 ,  H05K3/383 ,  H05K3/384 ,  H05K3/427 ,  H05K3/4602 ,  H05K3/4623 ,  H05K3/4661 ,  H05K2201/0195 ,  H05K2201/0352 ,  H05K2201/0358 ,  H05K2201/062 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/09827 ,  H05K2201/09863 ,  H05K2201/09881 ,  H05K2203/0307 ,  H05K2203/0353 ,  H05K2203/0554 ,  H05K2203/0773 ,  H05K2203/107 ,  H05K2203/121 ,  Y10T29/49117 ,  Y10T29/49124 ,  Y10T29/49126 ,  Y10T29/49128 ,  Y10T29/4913 ,  Y10T29/49155 ,  Y10T29/49156 ,  Y10T29/49165

Abstract: An opening is formed in resin 20 by a laser beam so that a via hole is formed. At this time, copper foil 22, the thickness of which is reduced (to 3 μm) by performing etching to lower the thermal conductivity is used as a conformal mask. Therefore, an opening 20a can be formed in the resin 20 if the number of irradiation of pulse-shape laser beam is reduced. Therefore, occurrence of undercut of the resin 20 which forms an interlayer insulating resin layer can be prevented. Thus, the reliability of the connection of the via holes can be improved.

Abstract translation: 通过激光束在树脂20中形成开口，从而形成通孔。 此时，通过进行蚀刻来降低导热率的铜箔22的厚度（3μm）被用作保形掩模。 因此，如果脉冲形激光束的照射次数减少，则可以在树脂20中形成开口20a。 因此，可以防止形成层间绝缘树脂层的树脂20的底切的发生。 因此，可以提高通孔连接的可靠性。

公开(公告)号：US07415761B2

公开(公告)日：2008-08-26

申请号：US10356464

申请日：2003-02-03

Applicant: Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

Inventor： Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

IPC: H01K3/10

CPC classification number: H05K3/4652 ,  B23K26/389 ,  H01L2224/16225 ,  H01L2924/15174 ,  H01L2924/15311 ,  H05K1/0201 ,  H05K3/0032 ,  H05K3/0035 ,  H05K3/0038 ,  H05K3/0055 ,  H05K3/0094 ,  H05K3/108 ,  H05K3/28 ,  H05K3/381 ,  H05K3/383 ,  H05K3/384 ,  H05K3/427 ,  H05K3/4602 ,  H05K3/4623 ,  H05K3/4661 ,  H05K2201/0195 ,  H05K2201/0352 ,  H05K2201/0358 ,  H05K2201/062 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/09827 ,  H05K2201/09863 ,  H05K2201/09881 ,  H05K2203/0307 ,  H05K2203/0353 ,  H05K2203/0554 ,  H05K2203/0773 ,  H05K2203/107 ,  H05K2203/121 ,  Y10T29/49117 ,  Y10T29/49124 ,  Y10T29/49126 ,  Y10T29/49128 ,  Y10T29/4913 ,  Y10T29/49155 ,  Y10T29/49156 ,  Y10T29/49165

Abstract: An opening is formed in resin 20 by a laser beam so that a via hole is formed. At this time, copper foil 22, the thickness of which is reduced (to 3 μm) by performing etching to lower the thermal conductivity is used as a conformal mask. Therefore, an opening 20a can be formed in the resin 20 if the number of irradiation of pulse-shape laser beam is reduced. Therefore, occurrence of undercut of the resin 20 which forms an interlayer insulating resin layer can be prevented. Thus, the reliability of the connection of the via holes can be improved.

Abstract translation: 通过激光束在树脂20中形成开口，从而形成通孔。 此时，通过进行蚀刻来降低导热率的铜箔22的厚度（3μm）被用作保形掩模。 因此，如果脉冲形激光束的照射次数减少，则可以在树脂20中形成开口部20a。 因此，可以防止形成层间绝缘树脂层的树脂20的底切的发生。 因此，可以提高通孔连接的可靠性。

公开(公告)号：US06591495B2

公开(公告)日：2003-07-15

申请号：US09797916

申请日：2001-03-05

Applicant: Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

Inventor： Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

IPC: H05K302

CPC classification number: H05K3/4652 ,  B23K26/389 ,  H01L2224/16225 ,  H01L2924/15174 ,  H01L2924/15311 ,  H05K1/0201 ,  H05K3/0032 ,  H05K3/0035 ,  H05K3/0038 ,  H05K3/0055 ,  H05K3/0094 ,  H05K3/108 ,  H05K3/28 ,  H05K3/381 ,  H05K3/383 ,  H05K3/384 ,  H05K3/427 ,  H05K3/4602 ,  H05K3/4623 ,  H05K3/4661 ,  H05K2201/0195 ,  H05K2201/0352 ,  H05K2201/0358 ,  H05K2201/062 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/09827 ,  H05K2201/09863 ,  H05K2201/09881 ,  H05K2203/0307 ,  H05K2203/0353 ,  H05K2203/0554 ,  H05K2203/0773 ,  H05K2203/107 ,  H05K2203/121 ,  Y10T29/49117 ,  Y10T29/49124 ,  Y10T29/49126 ,  Y10T29/49128 ,  Y10T29/4913 ,  Y10T29/49155 ,  Y10T29/49156 ,  Y10T29/49165

Abstract: An opening is formed in resin by a laser beam so that a via hole is formed. Copper foil, the thickness of which is reduced to 3 &mgr;m by etching to lower the thermal conductivity, is used as a conformal mask. Therefore, an opening is formed in the resin and the number of irradiation of pulse-shape laser beam is reduced. Thus, occurence of undercut of the resin, which forms an interlayer insulating resin layer, can be prevented and the reliability of the connection of the via holes can be improved.

Abstract translation: 通过激光束在树脂中形成开口，从而形成通孔。 铜箔的厚度通过蚀刻减少到3μm，以降低导热率，被用作保形掩模。 因此，在树脂中形成开口，并且脉冲形状的激光束的照射次数减少。 因此，可以防止形成层间绝缘树脂层的树脂的底切的发生，并且可以提高通孔的连接的可靠性。

公开(公告)号：US20120125680A1

公开(公告)日：2012-05-24

申请号：US13357663

申请日：2012-01-25

Applicant: Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

Inventor： Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

IPC: H05K1/02 ,  C25D5/02 ,  B23K1/20 ,  B23K31/02 ,  H05K3/46 ,  C25D7/00

CPC classification number: H05K3/4652 ,  B23K26/389 ,  H01L2224/16225 ,  H01L2924/15174 ,  H01L2924/15311 ,  H05K1/0201 ,  H05K3/0032 ,  H05K3/0035 ,  H05K3/0038 ,  H05K3/0055 ,  H05K3/0094 ,  H05K3/108 ,  H05K3/28 ,  H05K3/381 ,  H05K3/383 ,  H05K3/384 ,  H05K3/427 ,  H05K3/4602 ,  H05K3/4623 ,  H05K3/4661 ,  H05K2201/0195 ,  H05K2201/0352 ,  H05K2201/0358 ,  H05K2201/062 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/09827 ,  H05K2201/09863 ,  H05K2201/09881 ,  H05K2203/0307 ,  H05K2203/0353 ,  H05K2203/0554 ,  H05K2203/0773 ,  H05K2203/107 ,  H05K2203/121 ,  Y10T29/49117 ,  Y10T29/49124 ,  Y10T29/49126 ,  Y10T29/49128 ,  Y10T29/4913 ,  Y10T29/49155 ,  Y10T29/49156 ,  Y10T29/49165

Abstract: An opening is formed in resin 20 by a laser beam so that a via hole is formed. At this time, copper foil 22, the thickness of which is reduced (to 3 μm) by performing etching to lower the thermal conductivity is used as a conformal mask. Therefore, an opening 20a can be formed in the resin 20 if the number of irradiation of pulse-shape laser beam is reduced. Therefore, occurrence of undercut of the resin 20 which forms an interlayer insulating resin layer can be prevented. Thus, the reliability of the connection of the via holes can be prevented. Thus, the reliability of the connection of the via holes can be improved.

Abstract translation: 通过激光束在树脂20中形成开口，从而形成通孔。 此时，通过进行蚀刻来降低导热率的铜箔22的厚度（3μm）被用作保形掩模。 因此，如果脉冲形激光束的照射次数减少，则可以在树脂20中形成开口20a。 因此，可以防止形成层间绝缘树脂层的树脂20的底切的发生。 因此，可以防止通孔的连接的可靠性。 因此，可以提高通孔连接的可靠性。

公开(公告)号：US20080189943A1

公开(公告)日：2008-08-14

申请号：US12098582

申请日：2008-04-07

Applicant: Naohiro HIROSE ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

Inventor： Naohiro HIROSE ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

IPC: H05K3/42 ,  H01L21/306

CPC classification number: H05K3/4652 ,  B23K26/389 ,  H01L2224/16225 ,  H01L2924/15174 ,  H01L2924/15311 ,  H05K1/0201 ,  H05K3/0032 ,  H05K3/0035 ,  H05K3/0038 ,  H05K3/0055 ,  H05K3/0094 ,  H05K3/108 ,  H05K3/28 ,  H05K3/381 ,  H05K3/383 ,  H05K3/384 ,  H05K3/427 ,  H05K3/4602 ,  H05K3/4623 ,  H05K3/4661 ,  H05K2201/0195 ,  H05K2201/0352 ,  H05K2201/0358 ,  H05K2201/062 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/09827 ,  H05K2201/09863 ,  H05K2201/09881 ,  H05K2203/0307 ,  H05K2203/0353 ,  H05K2203/0554 ,  H05K2203/0773 ,  H05K2203/107 ,  H05K2203/121 ,  Y10T29/49117 ,  Y10T29/49124 ,  Y10T29/49126 ,  Y10T29/49128 ,  Y10T29/4913 ,  Y10T29/49155 ,  Y10T29/49156 ,  Y10T29/49165

Abstract: An opening is formed in resin 20 by a laser beam so that a via hole is formed. At this time, copper foil 22, the thickness of which is reduced (to 3 μm) by performing etching to lower the thermal conductivity is used as a conformal mask. Therefore, an opening 20a can be formed in the resin 20 if the number of irradiation of pulse-shape laser beam is reduced. Therefore, occurrence of undercut of the resin 20 which forms an interlayer insulating resin layer can be prevented. Thus, the reliability of the connection of the via holes can be improved.

Abstract translation: 通过激光束在树脂20中形成开口，从而形成通孔。 此时，通过进行蚀刻来降低导热率的铜箔22的厚度（3μm）被用作保形掩模。 因此，如果脉冲形激光束的照射次数减少，则可以在树脂20中形成开口部20a。 因此，可以防止形成层间绝缘树脂层的树脂20的底切的发生。 因此，可以提高通孔连接的可靠性。

公开(公告)号：US20080173473A1

公开(公告)日：2008-07-24

申请号：US11875486

申请日：2007-10-19

Applicant: Naohiro HIROSE ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

Inventor： Naohiro HIROSE ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

IPC: H01R12/04

CPC classification number: H05K3/4652 ,  B23K26/389 ,  H01L2224/16225 ,  H01L2924/15174 ,  H01L2924/15311 ,  H05K1/0201 ,  H05K3/0032 ,  H05K3/0035 ,  H05K3/0038 ,  H05K3/0055 ,  H05K3/0094 ,  H05K3/108 ,  H05K3/28 ,  H05K3/381 ,  H05K3/383 ,  H05K3/384 ,  H05K3/427 ,  H05K3/4602 ,  H05K3/4623 ,  H05K3/4661 ,  H05K2201/0195 ,  H05K2201/0352 ,  H05K2201/0358 ,  H05K2201/062 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/09827 ,  H05K2201/09863 ,  H05K2201/09881 ,  H05K2203/0307 ,  H05K2203/0353 ,  H05K2203/0554 ,  H05K2203/0773 ,  H05K2203/107 ,  H05K2203/121 ,  Y10T29/49117 ,  Y10T29/49124 ,  Y10T29/49126 ,  Y10T29/49128 ,  Y10T29/4913 ,  Y10T29/49155 ,  Y10T29/49156 ,  Y10T29/49165

Abstract: An opening is formed in resin 20 by a laser beam so that a via hole is formed. At this time, copper foil 22, the thickness of which is reduced (to 3 μm) by performing etching to lower the thermal conductivity is used as a conformal mask. Therefore, an opening 20a can be formed in the resin 20 if the number of irradiation of pulse-shape laser beam is reduced. Therefore, occurrence of undercut of the resin 20 which forms an interlayer insulating resin layer can be prevented. Thus, the reliability of the connection of the via holes can be improved.

Abstract translation: 通过激光束在树脂20中形成开口，从而形成通孔。 此时，通过进行蚀刻来降低导热率的铜箔22的厚度（3μm）被用作保形掩模。 因此，如果脉冲形激光束的照射次数减少，则可以在树脂20中形成开口部20a。 因此，可以防止形成层间绝缘树脂层的树脂20的底切的发生。 因此，可以提高通孔连接的可靠性。

公开(公告)号：US06613986B1

公开(公告)日：2003-09-02

申请号：US09787321

申请日：2001-05-17

Applicant: Naohiro Hirose ,  Honjin En

Inventor： Naohiro Hirose ,  Honjin En

IPC: H05K103

CPC classification number: H01L29/40 ,  H01L21/4763 ,  H01L2224/16227 ,  H01L2224/32225 ,  H01L2224/73204 ,  H01L2924/15311 ,  H05K1/0224 ,  H05K1/0253 ,  H05K1/03 ,  H05K3/064 ,  H05K3/244 ,  H05K3/382 ,  H05K3/403 ,  H05K3/4602 ,  H05K2201/0347 ,  H05K2201/062 ,  H05K2201/093 ,  H05K2201/09509 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/096 ,  H05K2201/09645 ,  H05K2201/09681 ,  H05K2203/1178

Abstract: Mesh holes 35a and 59a of upper solid layers 35 and upper solid layers 59 are formed to overlie on one another, so that the insulating properties of interlayer resin insulating layers 50 are not lowered. Here, the diameter of each mesh hole is preferably 75 to 300 &mgr;m. The reason is as follows. If the diameter of the mesh hole is less than 75 &mgr;m, it is difficult to overlay the upper and lower mesh holes on one another. If the diameter exceeds 300 &mgr;m, the insulating properties of the interlayer resin insulating layers deteriorate. In addition, the distance between the mesh holes is preferably 100 to 2000 &mgr;m. The reason is as follows. If the distance is less than 100 &mgr;m, the solid layer cannot function. If the distance exceeds 2000 &mgr;m, the deterioration of the insulating properties of the interlayer resin insulating film occurs.

公开(公告)号：US08148643B2

公开(公告)日：2012-04-03

申请号：US11875486

申请日：2007-10-19

Applicant: Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

Inventor： Naohiro Hirose ,  Kouta Noda ,  Hiroshi Segawa ,  Honjin En ,  Kiyotaka Tsukada ,  Naoto Ishida ,  Kouji Asano ,  Atsushi Shouda

IPC: H05K1/03

CPC classification number: H05K3/4652 ,  B23K26/389 ,  H01L2224/16225 ,  H01L2924/15174 ,  H01L2924/15311 ,  H05K1/0201 ,  H05K3/0032 ,  H05K3/0035 ,  H05K3/0038 ,  H05K3/0055 ,  H05K3/0094 ,  H05K3/108 ,  H05K3/28 ,  H05K3/381 ,  H05K3/383 ,  H05K3/384 ,  H05K3/427 ,  H05K3/4602 ,  H05K3/4623 ,  H05K3/4661 ,  H05K2201/0195 ,  H05K2201/0352 ,  H05K2201/0358 ,  H05K2201/062 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/09827 ,  H05K2201/09863 ,  H05K2201/09881 ,  H05K2203/0307 ,  H05K2203/0353 ,  H05K2203/0554 ,  H05K2203/0773 ,  H05K2203/107 ,  H05K2203/121 ,  Y10T29/49117 ,  Y10T29/49124 ,  Y10T29/49126 ,  Y10T29/49128 ,  Y10T29/4913 ,  Y10T29/49155 ,  Y10T29/49156 ,  Y10T29/49165

Abstract: An opening is formed in resin 20 by a laser beam so that a via hole is formed. At this time, copper foil 22, the thickness of which is reduced (to 3 μm) by performing etching to lower the thermal conductivity is used as a conformal mask. Therefore, an opening 20a can be formed in the resin 20 if the number of irradiation of pulse-shape laser beam is reduced. Therefore, occurrence of undercut of the resin 20 which forms an interlayer insulating resin layer can be prevented. Thus, the reliability of the connection of the via holes can be improved.

Abstract translation: 通过激光束在树脂20中形成开口，从而形成通孔。 此时，通过进行蚀刻来降低导热率的铜箔22的厚度（3μm）被用作保形掩模。 因此，如果脉冲形激光束的照射次数减少，则可以在树脂20中形成开口20a。 因此，可以防止形成层间绝缘树脂层的树脂20的底切的发生。 因此，可以提高通孔连接的可靠性。

公开(公告)号：US07847318B2

公开(公告)日：2010-12-07

申请号：US12406009

申请日：2009-03-17

Applicant: Naohiro Hirose ,  Honjin En

Inventor： Naohiro Hirose ,  Honjin En

IPC: H01L29/40 ,  H05K7/20

CPC classification number: H01L29/40 ,  H01L21/4763 ,  H01L2224/16227 ,  H01L2224/32225 ,  H01L2224/73204 ,  H01L2924/15311 ,  H05K1/0224 ,  H05K1/0253 ,  H05K1/03 ,  H05K3/064 ,  H05K3/244 ,  H05K3/382 ,  H05K3/403 ,  H05K3/4602 ,  H05K2201/0347 ,  H05K2201/062 ,  H05K2201/093 ,  H05K2201/09509 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/096 ,  H05K2201/09645 ,  H05K2201/09681 ,  H05K2203/1178

Abstract: Mesh holes 35a and 59a of upper solid layers 35 and upper solid layers 59 are formed to overlie on one another, so that the insulating properties of interlayer resin insulating layers 50 are not lowered. Here, the diameter of each mesh hole is preferably 75 to 300 μm. The reason is as follows. If the diameter of the mesh hole is less than 75 μm, it is difficult to overlay the upper and lower mesh holes on one another. If the diameter exceeds 300 μm, the insulating properties of the interlayer resin insulating layers deteriorate. In addition, the distance between the mesh holes is preferably 100 to 2000 μm. The reason is as follows. If the distance is less than 100 μm, the solid layer cannot function. If the distance exceeds 2000 μm, the deterioration of the insulating properties of the interlayer resin insulating film occurs.

Abstract translation: 上固体层35和上固体层59的网孔35a和59a形成为彼此重叠，使得层间树脂绝缘层50的绝缘性能不降低。 这里，每个网孔的直径优选为75〜300μm。 原因如下。 如果网孔的直径小于75μm，则难以将上，下网孔叠置在一起。 如果直径超过300μm，则层间树脂绝缘层的绝缘性变差。 此外，网孔之间的距离优选为100〜2000μm。 原因如下。 如果距离小于100μm，则固体层不能起作用。 如果距离超过2000μm，则发生层间树脂绝缘膜的绝缘性的劣化。

公开(公告)号：US20090173523A1

公开(公告)日：2009-07-09

申请号：US12406009

申请日：2009-03-17

Applicant: Naohiro HIROSE ,  Honjin En

Inventor： Naohiro HIROSE ,  Honjin En

IPC: H05K1/02

CPC classification number: H01L29/40 ,  H01L21/4763 ,  H01L2224/16227 ,  H01L2224/32225 ,  H01L2224/73204 ,  H01L2924/15311 ,  H05K1/0224 ,  H05K1/0253 ,  H05K1/03 ,  H05K3/064 ,  H05K3/244 ,  H05K3/382 ,  H05K3/403 ,  H05K3/4602 ,  H05K2201/0347 ,  H05K2201/062 ,  H05K2201/093 ,  H05K2201/09509 ,  H05K2201/09536 ,  H05K2201/0959 ,  H05K2201/096 ,  H05K2201/09645 ,  H05K2201/09681 ,  H05K2203/1178

Abstract: Mesh holes 35a and 59a of upper solid layers 35 and upper solid layers 59 are formed to overlie on one another, so that the insulating properties of interlayer resin insulating layers 50 are not lowered. Here, the diameter of each mesh hole is preferably 75 to 300 μm. The reason is as follows. If the diameter of the mesh hole is less than 75 μm, it is difficult to overlay the upper and lower mesh holes on one another. If the diameter exceeds 300 μm, the insulating properties of the interlayer resin insulating layers deteriorate. In addition, the distance between the mesh holes is preferably 100 to 2000 μm. The reason is as follows. If the distance is less than 100 μm, the solid layer cannot function. If the distance exceeds 2000 μm, the deterioration of the insulating properties of the interlayer resin insulating film occurs.

Abstract translation: 上固体层35和上固体层59的网孔35a和59a形成为彼此重叠，使得层间树脂绝缘层50的绝缘性能不降低。 这里，每个网孔的直径优选为75〜300μm。 原因如下。 如果网孔的直径小于75μm，则难以将上，下网孔叠置在一起。 如果直径超过300μm，则层间树脂绝缘层的绝缘性能变差。 此外，网眼之间的距离优选为100〜2000μm。 原因如下。 如果距离小于100um，则固体层不能起作用。 如果距离超过2000μm，则发生层间树脂绝缘膜的绝缘性劣化。