US4540603A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resin-molded semiconductor device and a process for manufacturing the same
Assignee: Hitachi Ltd
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Filing: 1983-12-19
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Granted: 1985-09-10
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Expires: 2003-12-19
Abstract
Abstract A process for manufacturing resin-molded semiconductor devices which are sealed in an epoxy resin is carried out without employing a metal mold. In the process, an epoxy resin is deposited on a sub-assembly consisting of a semiconductor pellet brazed to axial leads while turning the sub-assembly with the axial leads as a center so that the epoxy resin is applied to a predetermined shape; then the epoxy resin is heated at an elevated temperature while turning the sub-assembly so that surface portions of the epoxy resin are hardened and the epoxy resin is further heated at an elevated temperature without turning the sub-assembly so that the epoxy resin is completely hardened.
Inventors
- 👤 Toshiyuki Hidaka
- 👤 Hisashi Sakamoto
- 👤 Toshiaki Fukuhara
- 👤 Sadao Fujieda
- 👤 Yutaka Misawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:29
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/01; H10W74/10; H10W74/111; H10W74/121; H10W74/131; H10W74/137; H10W74/40; H10W74/47; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49169; Y10T29/49171
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
129 words
A process for manufacturing semiconductor devices comprising: a step of horizontally holding a sub-assembly that consists of a semiconductor pellet brazed to a pair of axial leads, and of depositing an epoxy resin of a predetermined amount onto the semiconductor pellet while turning the sub-assembly with the axial leads as a center; a step of heating the epoxy resin at a temperature of 160° to 180° C. for a period of 2 to 10 minutes while turning the sub-assembly, so that surface portions of the epoxy resin are hardened; and a step of heating the epoxy resin at a temperature of 160° to 200° C. for a period of 3 to 25 hours while maintaining the sub-assembly stationary without turning it, so that the epoxy resin is completely hardened.
Claim 2
Dependent Claim
129 words
A process for manufacturing semiconductor devices comprising: a step of horizontally holding a sub-assembly that consists of a semiconductor pellet brazed to a pair of axial leads, and of depositing an epoxy resin of a predetermined amount onto the semiconductor pellet while turning the sub-assembly with the axial leads as a center; a step of heating the epoxy resin at a temperature of 160° to 180° C. for a period of 2 to 10 minutes while turning the sub-assembly, so that surface portions of the epoxy resin are hardened; and a step of heating the epoxy resin at a temperature of 160° to 200° C. for a period of 3 to 25 hours while maintaining the sub-assembly stationary without turning it, so that the epoxy resin is completely hardened.
Claim 3
Dependent Claim
36 words
A process for manufacturing semiconductor devices according to claim 1, wherein the epoxy resin which is to be deposited has a thixotropic index of 1.0 to 2.5, and a gelation time of 0.8 to 3 minutes.
Claim 4
Dependent Claim
92 words
A process for manufacturing semiconductor devices according to claim 2, wherein the epoxy resin which is deposited is a one-can epoxy resin which has epoxy groups in the molecules, and which contains 3 to 15 moles of an organic dibasic acid dihydrazide per 100 moles of the epoxy resin, and 2 to 7 moles of an imidazole compound represented by the following formula; ##STR2## wherein R 1 is a methyl group, a hydrogen atom or a hydroxymethyl group, and R 2 is an alkyl group, per 100 moles of the epoxy resin.
Claim 5
Dependent Claim
74 words
A process for manufacturing semiconductor devices according to claim 2, wherein the epoxy resin which is deposited is a one-can epoxy resin which has epoxy groups in the molecules, and which contains 2 to 20 moles of the imidazole compound represented by the following formula; ##STR3## wherein R 1 is a methyl group, a hydrogen atom or a hydroxymethyl group, and R 2 is an alkyl group, per 100 moles of the epoxy resin.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-09 | 1989-03-11 | 1989-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-09 | 1993-03-11 | 1993-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-09 | 1997-03-11 | 1997-09-10 | $7700.00 | Window Closed / Lapsed |