US5388328A
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Process for fabricating an interconnected multilayer board
Assignee: Hitachi Ltd
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Filing: 1994-01-28
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Granted: 1995-02-14
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Expires: 2014-01-28
Abstract
Abstract A process for the fabrication of an interconnected multilayer board involves the steps of forming a metallic under-conductive layer on a base substrate, forming a windowed resist layer on the metallic under-conductive layer, filling windows of the resist layer with a conductor by plating thereby forming a conductor layer, forming another windowed resist layer on the conductor layer and filling windows of this resist layer with a conductor by plating, thereby forming a via-hole layer and to provide a two-level structure of the conductor layer and the via-hole layer. Thereafter, the resist layers and portions of the metallic under-conductor layer other than those in contact with a lower face of the conductor constituting the conductor layer are dissolved to form a two-level skeleton structure of conductor lines and spaces within the skeleton structure are filled with a varnish in a solventless form and the varnish is cured.
Inventors
- 👤 Hitoshi Yokono
- 👤 Hideo Arima
- 👤 Takashi Inoue
- 👤 Naoya Kitamura
- 👤 Haruhiko Matsuyama
- 👤 Hitoshi Oka
- 👤 Fumio Kataoka
- 👤 Fusaji Shoji
- 👤 Hideyasu Murooka
- 👤 Masayuki Kyooi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:22
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H05; H05K; H05K3/00; H05K3/46; H05K3/4644; H05K3/4647; H05K2203/00; H05K2203/07; H05K2203/0703; H05K2203/0733; H05K2203/0756; H05K2203/0769; H05K3/10; H05K3/108; H05K3/22; H05K3/24; H05K3/243; H10W72/00; H10W72/01; H10W72/012; H10W72/01251; H10W72/01255; H10W72/071; H10W72/072; H10W72/07251; H10W72/20; H10W72/851; H10W72/874; H10W72/877; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49126; Y10T29/49155; Y10T29/49165
Claims Analysis
Total Claims: 67
Claim 1
Independent Claim
159 words
A process for the fabrication of an interconnected multilayer board, which comprises forming a metallic under-conductive layer on a base substrate; forming a windowed resist layer on said metallic under-conductive layer; filling windows of the resist layer with a conductor by plating while using said metallic under-conductive layer as a base, thereby forming a conductor layer; forming another windowed resist layer on said conductor layer; filling windows of said resist layer on said conductor layer with a conductor by plating while using said conductor layer as a base, thereby forming a via-hole layer, to form a two-level structure of the conductor layer and the via-hole layer; dissolving the resist layers and portions of the metallic under-conductive layer, other than those in contact with lower face of the conductor constituting the conductor layer, thereby forming a two-level skeleton structure of conductor lines; filling spaces within said skeleton structure with a varnish in a solventless form and then curing the varnish.
Claim 2
Dependent Claim
159 words
A process for the fabrication of an interconnected multilayer board, which comprises forming a metallic under-conductive layer on a base substrate; forming a windowed resist layer on said metallic under-conductive layer; filling windows of the resist layer with a conductor by plating while using said metallic under-conductive layer as a base, thereby forming a conductor layer; forming another windowed resist layer on said conductor layer; filling windows of said resist layer on said conductor layer with a conductor by plating while using said conductor layer as a base, thereby forming a via-hole layer, to form a two-level structure of the conductor layer and the via-hole layer; dissolving the resist layers and portions of the metallic under-conductive layer, other than those in contact with lower face of the conductor constituting the conductor layer, thereby forming a two-level skeleton structure of conductor lines; filling spaces within said skeleton structure with a varnish in a solventless form and then curing the varnish.
Claim 3
Dependent Claim
39 words
The process of claim 1, wherein said varnish in a solventless form comprises at least one polymer selected from the group consisting of an epoxy resin, isocyanurate-oxazolidone resin, a cyanate ester resin, and a heat-resistant polymer containing cyclobutene rings.
Claim 4
Dependent Claim
48 words
The process of claim 2, wherein said varnish in a solventless form comprises said epoxy resin as said polymer, said epoxy resin being a heat-resistant epoxy resin having at least one ring structure selected from the group consisting of naphthalene ring, a biphenyl ring and a terphenyl ring.
Claim 5
Dependent Claim
32 words
The process of claim 2, wherein said varnish in a solventless form comprises said epoxy resin as said polymer and further comprises aromatic diamine as a curing agent for the epoxy resin.
Claim 6
Dependent Claim
38 words
The process of claim 4, wherein said aromatic diamine as the curing agent has at least a ring structure selected from the group consisting of a diphenylmethane ring, a naphthalene ring, a biphenyl ring and a terphenyl ring.
Claim 7
Dependent Claim
59 words
The process of claim 1, which further comprises a step of placing a reinforcing material in the spaces within the skeleton structure, before filling the spaces with said varnish in a solventless form, and wherein said varnish in a solventless form comprises a material selected from the group consisting of a poly(benzocyclobutene) polymer precursor and a heat-resistant epoxy resin.
Claim 8
Dependent Claim
28 words
The process of claim 1, wherein said varnish in a solventless form comprises either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin, which contains a reinforcing material.
Claim 9
Dependent Claim
39 words
The process of claim 1, wherein the conductor constituting the layers of the skeleton structure is coated with a solvent-based, heat-resistant varnish, before the spaces within the skeleton structure are filled with the heat-resistant varnish in a solventless form.
Claim 10
Dependent Claim
54 words
The process of claim 1, wherein a surface of the conductor of said via-hole layer is treated with a fluorine-containing compound before the spaces of said skeleton are filled with the varnish in a solventless form and said varnish in a solventless form contains either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 11
Dependent Claim
73 words
The process of claim 1, which further comprises the steps of forming a film of varnish in a solventless form on a flat surface of a hot plate, placing said varnish film downwardly together with the hot plate onto the conductor with the varnish film facing to the conductor, and heating and melting the varnish film so that the spaces within said skeleton structure are filled with the varnish in a solventless form.
Claim 12
Dependent Claim
23 words
The process of claim 10, wherein said varnish in a solventless form contains either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 13
Dependent Claim
29 words
The process of claim 10, wherein at least one of depressurization and depressurization followed by pressurization under a hydrostatic pressure, is applied when said heating and melting are conducted.
Claim 14
Dependent Claim
72 words
The process of claim 1, wherein the step of filling spaces within said skeleton structure with said varnish in a solventless form, is effected by placing a film of the varnish on the skeleton structure and by placing a hot plate on the film on said skeleton structure, whereby said varnish in a solventless form is melted due to the heat of the hot plate and fills spaces within said skeleton structure.
Claim 15
Dependent Claim
22 words
The process of claim 13, wherein said varnish in solventless form contains either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 16
Dependent Claim
29 words
The process of claim 13, wherein at least one of depressurization and depressurization followed by pressurization under a hydrostatic pressure, is applied when said heating and melting are conducted.
Claim 17
Dependent Claim
47 words
The process of claim 1, wherein the steps consisting of forming the two-level skeleton structure, and then filling the spaces within said skeleton structure with said varnish in a solventless form and curing the varnish are repeated a plurality of times to construct an interconnected multilayer substrate.
Claim 18
Dependent Claim
18 words
The process of claim 1, wherein said resist layers are formed with either a resist or a polymer.
Claim 19
Dependent Claim
22 words
The process of claim 1, wherein said plating base is either an electrode for electroplating or a base film for electroless plating.
Claim 20
Dependent Claim
194 words
The process for the fabrication of an interconnected multilayer board, which comprises forming a metallic under-conductive layer on a base substrate; forming a windowed resist layer on said metallic under-conductive layer; filling windows of the resist layer with a conductor by plating while using said metallic under-conductive layer as a base, thereby forming a conductor layer; forming another windowed resist layer on said conductor layer; filling windows of said resist layer on the conductor layer with a conductor by plating while using the conductor layer as a base, thereby forming a via-hole layer, to form a two-level structure of the conductor layer and the via-hole layer; repeating said steps from forming said metallic under-conductive layer to forming said via-hole layer a plurality of times to form a multilayer structure, and dissolving the resist layer and portions of the metallic under-conductive layers, other than those in contact with lower face of the conductor and the via-holes, thereby forming a multilevel skeleton structure of conductor lines; providing at least one spacer for fixing the conductors at desired positions; filling spaces within said skeleton structure with a varnish in a solventless form and then curing the varnish.
Claim 21
Dependent Claim
194 words
The process for the fabrication of an interconnected multilayer board, which comprises forming a metallic under-conductive layer on a base substrate; forming a windowed resist layer on said metallic under-conductive layer; filling windows of the resist layer with a conductor by plating while using said metallic under-conductive layer as a base, thereby forming a conductor layer; forming another windowed resist layer on said conductor layer; filling windows of said resist layer on the conductor layer with a conductor by plating while using the conductor layer as a base, thereby forming a via-hole layer, to form a two-level structure of the conductor layer and the via-hole layer; repeating said steps from forming said metallic under-conductive layer to forming said via-hole layer a plurality of times to form a multilayer structure, and dissolving the resist layer and portions of the metallic under-conductive layers, other than those in contact with lower face of the conductor and the via-holes, thereby forming a multilevel skeleton structure of conductor lines; providing at least one spacer for fixing the conductors at desired positions; filling spaces within said skeleton structure with a varnish in a solventless form and then curing the varnish.
Claim 22
Dependent Claim
23 words
The process of claim 19, wherein said spacer is formed with a different type of polymer from that used for said resist layers.
Claim 23
Dependent Claim
35 words
The process of claim 20, wherein the polymer employed to form the spacer is dissolved by neither a solvent capable of dissolving each resist layer nor an etchant capable of dissolving each metallic under-conductive layer.
Claim 24
Dependent Claim
40 words
The process of claim 19, wherein said spacer is formed at at least a part of the space other than the via-holes of said via-hole layer to fix the upper and lower conductors being in contact with said via-hole layer.
Claim 25
Dependent Claim
93 words
The process of claim 19, further comprising the steps of forming said spacer in accordance with a thin-film process, surrounding the conductor of the via-hole layer other than the upper and bottom surface of said conductor; filling the spaces other than the conductor on said via-hole layer and said spacer with a pre-plating metal before forming said conductor layer by plating said pre-plating metal as a base for plating; wherein said pre-plating metal is etched off after the forming of said conductor layer, said pre-plating metal being selectively etchable relative to the conductors.
Claim 26
Dependent Claim
57 words
The process of claim 19, wherein after said multilevel layer is formed, a fixing plate is provided over an uppermost layer of the multilevel structure, followed by the dissolving off portions of said resist layer and said metallic under-conductive layer other than those portions in contact with the lower part of conductor which constitutes the conductive layer.
Claim 27
Dependent Claim
39 words
The process of claim 19, wherein said varnish in a solventless form contains at least one polymer selected from a group of an epoxy resin, an isocyanurate-oxazolidone resin, a cyanate ester resin, and a heat-resistant polymer containing cyclobutene rings.
Claim 28
Dependent Claim
48 words
The process of claim 25, wherein said varnish in a solventless form contains said epoxy resin as said polymer, said epoxy resin being a heat-resistant epoxy resin having at least ring structure selected from the group consisting of a naphthalene ring, a biphenyl ring, and a terphenyl ring.
Claim 29
Dependent Claim
31 words
The process of claim 25, wherein said varnish in a solventless form comprises said epoxy resin as said polymer and further an aromatic diamine as a curing agent of the polymer.
Claim 30
Dependent Claim
35 words
The process of claim 25, wherein said aromatic diamine as the curing agent has at least one ring structure selected from the group consisting of a diphenylmethane ring, a biphenyl ring and a terphenyl ring.
Claim 31
Dependent Claim
51 words
The process of claim 19, which further comprises a step of placing a reinforcing material in the spaces within the skeleton structure before filling the spaces with said varnish in a solventless form, wherein said varnish in a solventless form comprises either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 32
Dependent Claim
40 words
The process of claim 19, wherein said varnish in a solventless form for filling the space of the skeleton structure and to be cured is either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin, which contain a reinforcing material.
Claim 33
Dependent Claim
41 words
The process of claim 19, wherein the conductor constituting the skeleton structure is coated with a solvent-based, heat-resistant varnish, then the spaces within the skeleton structure are filled with the heat-resistant varnish in a solventless form and the varnish is cured.
Claim 34
Dependent Claim
55 words
The process of claim 19, wherein a surface of the conductor of said via-hole layer is treated with a fluorine-containing compound before the spaces of said skeleton are filled with the varnish in a solventless form and wherein said varnish in a solventless form contains either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 35
Dependent Claim
72 words
The process of claim 19, which further comprises the steps of forming a film of varnish in a solventless form on a flat surface of a hot plate, placing said varnish film downwardly together with the hot plate onto the conductors with the varnish film facing to the conductors, heating and melting the varnish film so that the spaces within said skeleton structure are filled with the varnish in a solventless form.
Claim 36
Dependent Claim
23 words
The process of claim 33, wherein said varnish in a solventless form contains either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 37
Dependent Claim
29 words
The process of claim 33, wherein at least one of depressurization and depressurization followed by pressurization under a hydrostatic pressure, is applied when said heating and melting are conducted.
Claim 38
Dependent Claim
76 words
The process of claim 19, wherein the step of filling spaces within said skeleton structure with said varnish in a solventless form, is effected by placing a film of the varnish in a solventless form on the skeleton structure and placing a hot plate on and the film on said skeleton structure, whereby said varnish in a solventless form is melted due to the heat of the hot plate and fills spaces within said skeleton structure.
Claim 39
Dependent Claim
22 words
The process of claim 36, wherein said varnish in solventless form contains either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 40
Dependent Claim
29 words
The process of claim 36, wherein at least one of depressurization and depressurization followed by pressurization under a hydrostatic pressure, is applied when said heating and melting are conducted.
Claim 41
Dependent Claim
36 words
The process of claim 19, wherein the steps of forming the skeleton structure having a predetermined number of the conductor layers and via-hole layers are repeated a plurality of times to construct an interconnected multilayer substrate.
Claim 42
Dependent Claim
18 words
The process of claim 19, wherein said resist layers are formed with either a resist or a polymer.
Claim 43
Dependent Claim
22 words
The process of claim 19, wherein said plating base is either an electrode for electroplating or a base film for electroless plating.
Claim 44
Dependent Claim
154 words
The process for the fabrication of an interconnected multilayer board, comprising the steps of forming a metallic under-conductive layer on a base substrate; forming a windowed resist layer on said metallic under-conductive layer; filling windows of the resist layer with a conductor by plating while using said metallic under-conductive layer as a base, thereby forming a conductor layer; repeating said steps from forming said metallic under-conductive layer to filling of said conductor a plurality of times to form a multilayer structure containing said conductors; dissolving off the resist layers and portions of the metallic under-conductive layers, other than those in contact with a lower face of the conductor in said layers containing the conductor, thereby forming a multilevel skeleton structure of conductor lines; providing at least one spacer for fixing the conductors at desired positions; filling the spaces within said skeleton structure with a varnish in a solventless form and then curing the varnish.
Claim 45
Dependent Claim
154 words
The process for the fabrication of an interconnected multilayer board, comprising the steps of forming a metallic under-conductive layer on a base substrate; forming a windowed resist layer on said metallic under-conductive layer; filling windows of the resist layer with a conductor by plating while using said metallic under-conductive layer as a base, thereby forming a conductor layer; repeating said steps from forming said metallic under-conductive layer to filling of said conductor a plurality of times to form a multilayer structure containing said conductors; dissolving off the resist layers and portions of the metallic under-conductive layers, other than those in contact with a lower face of the conductor in said layers containing the conductor, thereby forming a multilevel skeleton structure of conductor lines; providing at least one spacer for fixing the conductors at desired positions; filling the spaces within said skeleton structure with a varnish in a solventless form and then curing the varnish.
Claim 46
Dependent Claim
16 words
The process of claim 42, wherein said at least one spacer is formed by a polymer.
Claim 47
Dependent Claim
38 words
The process of claim 43, wherein the polymer employed to form the at least one spacer is dissolved by neither a solvent capable of dissolving each resist nor by an etchant capable of dissolving each metallic under-conductive layer.
Claim 48
Dependent Claim
51 words
The process of claim 42, wherein said at least one spacer is formed at least in a part of the spaces, said part of the spaces being other than the via-holes of said via-hole layer so that the upper and lower conductors being in contact with said via-hole layer are fixed.
Claim 49
Dependent Claim
107 words
The process of claim 42, further comprising the steps of forming said at least one spacer surrounding the conductors of the via-hole layer other than the upper and bottom surface of said conductors, in accordance with a thin-film process, filling the spaces other than the conductor on said via-hole layer and said spacer with a pre-plating metal and forming said conductor layer by plating said pre-plating metal and forming said conductor layer by plating said pre-plating metal as a base for plating, and wherein said pre-plating metal is etched off after the forming of said conductor layer, said pre-plating metal being selectively etchable relative to the conductors.
Claim 50
Dependent Claim
57 words
The process of claim 42, wherein after said multilevel structure is formed, a fixing plate is provided over an uppermost layer of the multilevel structure, followed by the dissolving off of said resist layer and portions of said metallic under-conductive layer other than those in contact with the lower face of conductors which construct the conductive layer.
Claim 51
Dependent Claim
42 words
The process of claim 42, wherein said varnish in a solventless form contains at least one type of polymer selected from the group consisting of an epoxy resin, an isocyanurate-oxazolidone resin, a cyanate ester resin, and a heat-resistant polymer containing cyclobutene rings.
Claim 52
Dependent Claim
49 words
The process of claim 48, wherein said varnish in a solventless form contains said epoxy resin as said polymer, said epoxy resin being a heat-resistant epoxy resin having at least one ring structure selected from the group consisting of a naphthalene ring, a biphenyl ring, and a terphenyl ring.
Claim 53
Dependent Claim
32 words
The process of claim 48, wherein said varnish in a solventless form comprises said epoxy resin as said polymer and further comprises an aromatic diamine as a curing agent for the polymer.
Claim 54
Dependent Claim
38 words
The process of claim 48, wherein said aromatic diamine as the curing agent has at least one ring structure selected from the group consisting of a diphenylmethane ring, a naphthalene ring, a biphenyl ring and a terphenyl ring.
Claim 55
Dependent Claim
52 words
The process of claim 42, which further comprises a step of placing a reinforcing material in the spaces within the skeleton structure before filling the spaces with said varnish in a solventless form, and wherein said varnish in a solventless form comprises either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 56
Dependent Claim
40 words
The process of claim 42, wherein said varnish in a solventless form for filling the spaces of the skeleton structure and to be cured is either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin, which contain a reinforcing material.
Claim 57
Dependent Claim
36 words
The process of claim 42, wherein the conductor constituting the skeleton structure is coated with a solvent-based, heat-resistant varnish, before the spaces within the skeleton structure are filled with the heat-resistant varnish in a solventless form.
Claim 58
Dependent Claim
54 words
The process of claim 42, wherein a top surface of the conductors of said conductor layer is treated with a fluorine-containing compound before the spaces of said skeleton are filled with the varnish in a solventless form; said varnish in a solventless form containing either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 59
Dependent Claim
73 words
The process of claim 42, which further comprises the steps of forming a film of varnish in a solventless form on a flat surface of a hot plate, placing said varnish film downwardly together with the hot plate onto the conductor with the varnish film facing to the conductor, and heating and melting the varnish film so that the spaces within said skeleton structure are filled with the varnish in a solventless form.
Claim 60
Dependent Claim
23 words
The process of claim 56, wherein said varnish in a solventless form contains either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 61
Dependent Claim
29 words
The process of claim 56, wherein at least one of depressurization and depressurization followed by pressurization under a hydrostatic pressure, is applied when said heating and melting are conducted.
Claim 62
Dependent Claim
73 words
The process of claim 56, wherein filling spaces within said skeleton structure with said varnish in a solventless form, is effected by forming a film of the varnish in solventless form on the skeleton structure and by placing a hot plate on the film on said skeleton structure, whereby said varnish in a solventless form is melted due to the heat of the hot plate and fills the spaces with said skeleton structure.
Claim 63
Dependent Claim
22 words
The process of claim 59, wherein said varnish in solventless form contains either a poly(benzocyclobutene) polymer precursor or a heat-resistant epoxy resin.
Claim 64
Dependent Claim
29 words
The process of claim 59, wherein at least one of depressurization, or depressurization followed by pressurization under a hydrostatic pressure is applied when said heating and melting are conducted.
Claim 65
Dependent Claim
36 words
The process of claim 42, wherein the steps of forming the skeleton structure having a predetermined number of the conductor layers and via-hole layers are repeated a plurality of times to construct an interconnected multilayer substrate.
Claim 66
Dependent Claim
18 words
The process of claim 42, wherein said resist layers are formed with either a resist or a polymer.
Claim 67
Dependent Claim
22 words
The process of claim 42, wherein said plating base is either an electrode for electroplating or a base film for electroless plating.
References Cited (Backward Citations)
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