Patent EP0085974A2 successfully refreshed from Google Patents.
EP0085974A2
Expired / Lapsed
EP
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Method of forming a number of solder portions on a semiconductor wafer
Assignee: Hitachi Ltd
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Filing: 1983-02-07
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Granted: —
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Expires: 2003-02-07
Abstract
Abstract A method of forming a number of discrete solder layers (9) on a semiconductor wafer (1) of a large area. A number of regions (2) which are easy to be wetted with solder are formed on one of the major surfaces of the wafer (1). A solder foil (6) is positioned on the one major surface and a plate-like jig (7) including a plate and projections (71) formed on one surface thereof is disposed on the solder foil (6) with the projections (71) facing the latter. By heating the stacked assembly at a sufficiently high temperature for the solder foil (6) to be moften, a number of the discrete solder layers (9) having a uniform thickness are formed on the semiconductor wafer (1).
Inventors
- 👤 Tadao Kushima
- 👤 Masahiro Gooda
- 👤 Tasao Soga
- 👤 Toshitaka Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 19:34
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/01; H10W72/012; H10W72/20; H10W72/251
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
166 words
A method of forming a number of discrete solder layers on a semiconductor wafer, comprising steps of: forming at least on one of major surfaces of said semiconductor wafer (1) a number of first regions (2) easily wettable with solder and second regions (4, 5,13) which are difficultly wettable with solder, said second regions (4, 5, 13) separating said first regions (2) from one another; disposing a solder foil (6) on said one major surface of said semiconductor wafer (1) ; disposing on said solder foil (6) positioned on said semiconductor wafer (1) a plate-like jig (7) composed of a plate and projections (71) of a desired height formed at least on one surface of said plate in such a manner that said projections (71) face said solder foil (6); and heating a stacked structure including said semiconductor wafer (1), said solder foil (6) and said plate-like jig (7) in a non-oxidizing atmosphere to a sufficiently high temperature for said solder foil (6) to be molten.
Claim 2
Independent Claim
166 words
A method of forming a number of discrete solder layers on a semiconductor wafer, comprising steps of: forming at least on one of major surfaces of said semiconductor wafer (1) a number of first regions (2) easily wettable with solder and second regions (4, 5,13) which are difficultly wettable with solder, said second regions (4, 5, 13) separating said first regions (2) from one another; disposing a solder foil (6) on said one major surface of said semiconductor wafer (1) ; disposing on said solder foil (6) positioned on said semiconductor wafer (1) a plate-like jig (7) composed of a plate and projections (71) of a desired height formed at least on one surface of said plate in such a manner that said projections (71) face said solder foil (6); and heating a stacked structure including said semiconductor wafer (1), said solder foil (6) and said plate-like jig (7) in a non-oxidizing atmosphere to a sufficiently high temperature for said solder foil (6) to be molten.
Claim 3
Dependent Claim
28 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 1, wherein said solder foil (6) is of a net-like structure.
Claim 4
Dependent Claim
102 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 1, wherein apertures (61) are formed in said solder foil (6) at those portions which correspond, respectively, to said second regions (4, 5, 13) of said semiconductor wafer (1) which are difficult to be wetted with solder, while those portions of said solder foil which are located adjacent to said apertures (6) being left as they are, each of said aperture (6) extending to each of said first regions (2) easily wettable with solder, said solder foil thus presenting a net-like structure as a whole.
Claim 5
Dependent Claim
76 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 1, wherein said first regions (2) of said semiconductor wafer which are easy to be wetted with solder are formed by depositing a metal film (2) which can be contacted to said semiconductor wafer and are easily wettable with solder, while said second regions difficultly wettable with solder are formed through deposition of an insulation film (4, 5, 13).
Claim 6
Independent Claim
176 words
A method of forming a number of discrete solder layers on a semiconductor wafer, comprising steps of: forming on a pair of opposite major surfaces of said semiconductor wafer (1) a number of first regions (2, 3) easily wettable with solder and a number of second regions (4, 5, 13) difficultly wettable with solder in a juxtaposed array, wherein said second regions (4, 5, 13) separating said first regions (2, 3) from one another; disposing solder foils (6) on both the major surfaces, respectively, of said semiconductor wafer (1); disposing on each of said solder foils (6) positioned on said semiconductor wafer (1) a plate-like jig (7) composed of a plate and projections (71) of a desired height formed at least on one surface of said plate in such a manner that said projections (71) face said solder foil (6); and heating a stacked structure including said semiconductor wafer (1), said solder foils (6) and said plate-like jigs (7) in a non-oxidizing atmosphere to a sufficiently high temperature for said solder foils (6) to be molten.
Claim 7
Independent Claim
176 words
A method of forming a number of discrete solder layers on a semiconductor wafer, comprising steps of: forming on a pair of opposite major surfaces of said semiconductor wafer (1) a number of first regions (2, 3) easily wettable with solder and a number of second regions (4, 5, 13) difficultly wettable with solder in a juxtaposed array, wherein said second regions (4, 5, 13) separating said first regions (2, 3) from one another; disposing solder foils (6) on both the major surfaces, respectively, of said semiconductor wafer (1); disposing on each of said solder foils (6) positioned on said semiconductor wafer (1) a plate-like jig (7) composed of a plate and projections (71) of a desired height formed at least on one surface of said plate in such a manner that said projections (71) face said solder foil (6); and heating a stacked structure including said semiconductor wafer (1), said solder foils (6) and said plate-like jigs (7) in a non-oxidizing atmosphere to a sufficiently high temperature for said solder foils (6) to be molten.
Claim 8
Dependent Claim
28 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 5, wherein said solder foils (6) are of a net-like structure.
Claim 9
Dependent Claim
101 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 5, wherein apertures (61) are formed in said solder foil at those portions which correspond, respectively, to said second regions (4, 5, 13) of said semiconductor wafer which are difficult to be wetted with solder, while those portions of said solder foils (6) which are located adjacent to said apertures (61) being left as they are, each of said aperture (61) extending to each of said first regions (2) easily wettable with solder, said solder foil thus presenting a net-like structure as a whole.
Claim 10
Dependent Claim
80 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 5, wherein said first regions (2, 3) of said semiconductor wafer (1) which are easy to be wetted with solder are formed by depositing a metal film (2, 3) which can be contacted to said semiconductor wafer (1) and are easily wettable with solder, while said second regions difficultly wettable with solder are formed through deposition of an insulation film (4, 5, 13).
Claim 11
Independent Claim
183 words
A method of forming a number of discrete solder layers on a semiconductor wafer, comprising steps of: forming on at least one of major surfaces of said semiconductor wafer (1) a number of metal electrodes (2) having a substantially same shape in orthogonal X-and Y- directions with a predetermined distance between adjacent ones of said electrodes (2) in a juxtaposed array, to thereby form first regions (2) which are easy to be wetted with solder and second regions (13) which are difficult to be wetted with solder; disposing a solder foil (6) on said one major surface of said semiconductor wafer (1); disposing on said solder foil positioned on said semiconductor wafer a plate-like jig (7) composed of a plate and projections (71) of a desired height formed at least on one surface of said plate in such a manner that said projections face said solder foil (6); and heating a stacked structure including said semiconductor wafer (1), said solder foil (6) and said plate-like jig (7) in a non-oxidizing atmosphere to a sufficiently high temperature for said solder foil to be molten.
Claim 12
Independent Claim
183 words
A method of forming a number of discrete solder layers on a semiconductor wafer, comprising steps of: forming on at least one of major surfaces of said semiconductor wafer (1) a number of metal electrodes (2) having a substantially same shape in orthogonal X-and Y- directions with a predetermined distance between adjacent ones of said electrodes (2) in a juxtaposed array, to thereby form first regions (2) which are easy to be wetted with solder and second regions (13) which are difficult to be wetted with solder; disposing a solder foil (6) on said one major surface of said semiconductor wafer (1); disposing on said solder foil positioned on said semiconductor wafer a plate-like jig (7) composed of a plate and projections (71) of a desired height formed at least on one surface of said plate in such a manner that said projections face said solder foil (6); and heating a stacked structure including said semiconductor wafer (1), said solder foil (6) and said plate-like jig (7) in a non-oxidizing atmosphere to a sufficiently high temperature for said solder foil to be molten.
Claim 13
Dependent Claim
87 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 9, wherein apertures (61) are formed in said solder foil (6) at those locations which correspond, respectively, to portions lying among the adjacent metal electrodes (2), while those portions of said solder foil which are located adjacent to said apertures being left as they are, each of said apertures (6) extending to each of said metal electrodes (2), said solder foil (6) thus presenting a net-like structure as a whole.
Claim 14
Dependent Claim
46 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 10, wherein said metal electrode is of a substantially square shape, while said aperture formed in said solder foil is of a circular shape (Fig. 1 to Fig. 5).
Claim 15
Independent Claim
235 words
A method of forming a number of discrete solder layers on a semiconductor wafer, comprising steps of: forming on one of major surfaces of said semiconductor wafer (1) a number of first metal electrodes (2) having a substantially same shape and positioned in orthogonal X- and Y- directions with a predetermined distance between adjacent ones of said electrodes (2) in a juxtaposed array, to thereby form regions which are easy to be wetted with solder and regions (13) which are difficult to be wetted with solder, and forming on the other major surface (12) of said wafer a number of second juxtaposed metal electrodes (3) of a substantially same form in correspondence with said first metal electrode, to thereby provide said other major surface with regions (3) easily wettable with solder and regions difficultly wettable with solder; disposing solder foils (6) on both the major surfaces, respectively, of said semiconductor wafer; disposing on each of said solder foils (6) positioned on said semiconductor wafer a plate-like jig (7) composed of a plate and projections (71) of a desired height formed at least on one surface of said plate in such a manner that said projections face said solder foil; and heating a stacked structure including said semiconductor wafer (1), said solder foils (6) and said plate-like jigs (7) in non-oxidizing atmosphere to a sufficiently high temperature for said solder foils to be molten. (Fig. 7)
Claim 16
Independent Claim
235 words
A method of forming a number of discrete solder layers on a semiconductor wafer, comprising steps of: forming on one of major surfaces of said semiconductor wafer (1) a number of first metal electrodes (2) having a substantially same shape and positioned in orthogonal X- and Y- directions with a predetermined distance between adjacent ones of said electrodes (2) in a juxtaposed array, to thereby form regions which are easy to be wetted with solder and regions (13) which are difficult to be wetted with solder, and forming on the other major surface (12) of said wafer a number of second juxtaposed metal electrodes (3) of a substantially same form in correspondence with said first metal electrode, to thereby provide said other major surface with regions (3) easily wettable with solder and regions difficultly wettable with solder; disposing solder foils (6) on both the major surfaces, respectively, of said semiconductor wafer; disposing on each of said solder foils (6) positioned on said semiconductor wafer a plate-like jig (7) composed of a plate and projections (71) of a desired height formed at least on one surface of said plate in such a manner that said projections face said solder foil; and heating a stacked structure including said semiconductor wafer (1), said solder foils (6) and said plate-like jigs (7) in non-oxidizing atmosphere to a sufficiently high temperature for said solder foils to be molten. (Fig. 7)
Claim 17
Dependent Claim
87 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 12, wherein aperture (61) are formed in each said solder foils (6) at those locations which correspond, respectively, to portions lying among the adjacent metal electrodes (2), while those portions of said solder foil which are located adjacent to said apertures being left as they are, each of said apertures (61) extending to each of said metal electrodes, said solder foil (6) thus presenting a net-like structure as a whole.
Claim 18
Dependent Claim
43 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 13, wherein said metal electrode (2) is of a substantially square shape, while said aperture (61) formed in said solder foil is of a circular shape.
Claim 19
Dependent Claim
49 words
A method of forming a number of discrete solder layers on a semiconductor wafer according to claim 13, wherein each of those portions (63) of said solder foil (6) which correspond to locations lying among the adjacent metal electrodes (2) has a mid portion which is narrowest in width.
References Cited (Backward Citations)
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