US4675985A
Expired / Lapsed
US
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Method for manufacturing a semiconductor memory device having a high radiation resistance
Assignee: Fujitsu Ltd
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Filing: 1984-01-04
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Granted: 1987-06-30
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Expires: 2004-01-04
Abstract
Abstract In a method for manufacturing a semiconductor memory device, a semiconductor chip and an adhesive tape having an adhesive layer are prepared. The adhesive layer comprises a polyamic acid intermediate derived for example from a pyromellitic dianhydride and a diamine. The adhesive tape is pressed onto the semiconductor chip at a temperature of from about 250° C. to about 400° C. for a predetermined time period such as 2 to 5 sec.
Inventors
- 👤 Junichi Goto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:16
CPC Classifications
H; H10; H10W; H10W42/00; H10W42/20; H10W42/25; H10W72/00; H10W72/30; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W70/682; H10W72/071; H10W72/073; H10W72/07331; H10W72/07337; H10W72/851; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/731; H10W90/734; Y; Y10; Y10S; Y10S438/00; Y10S438/914; Y10S438/918
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
101 words
A method for manufacturing a semiconductor memory device having a high resistance to radiation, comprising the steps of: preparing a semiconductor chip with a passivation layer of phosphosilicate glass or silicon dioxide; preparing an adhesive tape comprising a radiation-resistant layer and an adhesive layer on a surface of said radiation resistant layer, said adhesive layer comprising a polyamic acid intermediate; directly pressing said adhesive layer of said adhesive tape onto said passivation layer of said semiconductor chip while the chip is heated at a temperature in the range from about 250° C. to about 400° C. for a predetermined time period.
Claim 2
Independent Claim
101 words
A method for manufacturing a semiconductor memory device having a high resistance to radiation, comprising the steps of: preparing a semiconductor chip with a passivation layer of phosphosilicate glass or silicon dioxide; preparing an adhesive tape comprising a radiation-resistant layer and an adhesive layer on a surface of said radiation resistant layer, said adhesive layer comprising a polyamic acid intermediate; directly pressing said adhesive layer of said adhesive tape onto said passivation layer of said semiconductor chip while the chip is heated at a temperature in the range from about 250° C. to about 400° C. for a predetermined time period.
Claim 3
Dependent Claim
22 words
A method as set forth in claim 1, wherein said polyamic acid intermediate is modified with an organic silicone or aluminum chelate.
Claim 4
Dependent Claim
14 words
A method as set forth in claim 1, wherein said dianhydride is pyromellitic dianhydride.
Claim 5
Dependent Claim
14 words
A method as set forth in claim 1, wherein said dianhydride is benzophenonetetracarboxylic dianhydride.
Claim 6
Dependent Claim
25 words
A method as set forth in claim 1, wherein said predetermined time period is in the range from about 2 sec to about 10 sec.
Claim 7
Dependent Claim
22 words
A method as set forth in claim 5, wherein said range of said predetermined time period is up to about 5 sec.
Claim 8
Dependent Claim
35 words
A method as set forth in claim 1, further comprising the step of curing said semiconductor memory device at a temperature of about 250° C. for a further predetermined time period, after the pressing step.
Claim 9
Dependent Claim
18 words
A method as set forth in claim 7, wherein said further predetermined time period is about 1 hour.
Claim 10
Dependent Claim
19 words
A method as set forth in claim 1, wherein said range of temperature extends up to about 350° C.
Claim 11
Dependent Claim
30 words
A method as set forth in claim 1, wherein said radiation-resistant layer comprises a polyimide having a thickness in the range from about 75 μm to about 12 -5 μm.
Claim 12
Dependent Claim
26 words
A method as set forth in claim 1, wherein the thickness of said adhesive layer is in the range from about 10 to about 30 μm.
Claim 13
Dependent Claim
29 words
The method of claim 1, wherein said adhesive layer is provided with a peak value in the distribution of its molecular weight that is less than 10 5 .
Claim 14
Dependent Claim
14 words
The method of claim 12, said peak value being less than 10 4 .
Claim 15
Dependent Claim
29 words
The method of claim 12, wherein said distribution of molecular weight is provided with a half-maximum width of more than approximately one order of magnitude on a decimal scale.
Claim 16
Dependent Claim
21 words
The method of claim 14, wherein said half-maximum width is provided with about 2 or more of said orders of magnitude.
Claim 17
Dependent Claim
15 words
The method of claim 1, said polyamic acid intermediate being of the general formula ##STR6##
Claim 18
Dependent Claim
10 words
The method of claim 16, said dianhydride being pyromellitic dianhydride.
Claim 19
Dependent Claim
22 words
The method of claim 1, said polyamic acid intermediate being of the general formula ##STR7## wherein AR is an aromatic hydrocarbon group.
Claim 20
Dependent Claim
11 words
The method of claim 18, said AR being a phenyl group.
Claim 21
Dependent Claim
15 words
The method of claim 19, said dianhydride being benzophenonetetracarboxylic dianhydride which has the formula ##STR8##
Claim 22
Dependent Claim
10 words
The method of claim 20, said phenyl group being ##STR9##
Claim 23
Dependent Claim
10 words
The method of claim 19, said phenyl group being ##STR10##
Claim 24
Dependent Claim
10 words
The method of claim 22, said dianhydride being pyromellitic dianhydride.
Claim 25
Dependent Claim
13 words
The method of claim 1, said range being from above about 250° C.
Claim 26
Dependent Claim
17 words
The method of claim 1, comprising a passivation layer on said chip, said passivation layer excluding polyimide.
Claim 27
Dependent Claim
33 words
The method of claim 1, wherein said pressing of said adhesive layer of said adhesive tape onto said chip occurs at a pressure in the range from 200 to 1000 g/cm 2 .
References Cited (Backward Citations)
US4284461A
Cited
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