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US5514628A Expired / Lapsed US ⏱️ 0.0 years remaining

Two-step sinter method utilized in conjunction with memory cell replacement by redundancies

Assignee: Texas Instruments Inc
•
Filing: 1995-05-26
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Granted: 1996-05-07
•
Expires: 2015-05-26
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Abstract

Abstract A process is disclosed herein for increasing yield in a semiconductor circuity having redundant circuitry for replacing defective normal circuitry in the semiconductor integrated circuit. In the first step, an insufficient sinter operation (50) is carried out in a hydrogen atmosphere at a temperature of less than 350 DEG C. At this temperature, no significant change will be seen in the interface trap density. Thereafter, the integrated circuit is tested (54,56) and the defective normal circuitry then is replaced (58) with the redundant circuitry. The integrated circuit is then subjected to a sufficient sinter operation (64) which is an operation wherein the substrate is disposed at a temperature between 350 DEG C.-500 DEG C. for more than 30 minutes. This sufficient sinter operation is performed in a hydrogen atmosphere, allowing dangling bonds at the interface to be terminated with hydrogen. Preferable, the optimal temperature for the sufficient sinter is approximately 400 DEG C. The integrated circuit is then subjected to a reliability and burn-in procedure.

Inventors

  • 👤 Osaomi Enomoto
  • 👤 Yoichi Miyai
  • 👤 Yoshihiro Ogata
  • 👤 Yoshinobu Yoneoka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 09:09
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/90; H10D; H10D84/00; H10D84/90

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 139 words
A process for increasing yield in a semiconductor integrated circuit having normal circuitry and redundant circuitry for replacing defective normal circuitry in the semiconductor circuit, the process comprising the steps of: after formation of the circuitry on the integrated circuit, subjecting the integrated circuit to an insufficient sinter operation in an atmosphere having a hydrogen constituent that uses an operating environment that approximately maintains an interface trap density in the integrated circuit; testing the integrated circuit to determine if any of the normal circuitry on the integrated circuit is defective; replacing the defective normal circuitry on the integrated circuit with corresponding redundant circuitry; and thereafter subjecting the integrated circuit to a sufficient sinter operation in an atmosphere having a hydrogen constituent that uses an operating environment that causes a decrease in the interface trap density in the integrated circuit.
Claim 2
Dependent Claim 139 words
A process for increasing yield in a semiconductor integrated circuit having normal circuitry and redundant circuitry for replacing defective normal circuitry in the semiconductor circuit, the process comprising the steps of: after formation of the circuitry on the integrated circuit, subjecting the integrated circuit to an insufficient sinter operation in an atmosphere having a hydrogen constituent that uses an operating environment that approximately maintains an interface trap density in the integrated circuit; testing the integrated circuit to determine if any of the normal circuitry on the integrated circuit is defective; replacing the defective normal circuitry on the integrated circuit with corresponding redundant circuitry; and thereafter subjecting the integrated circuit to a sufficient sinter operation in an atmosphere having a hydrogen constituent that uses an operating environment that causes a decrease in the interface trap density in the integrated circuit.
Claim 3
Dependent Claim 23 words
To the process of claim 1, wherein the insufficient sinter operation is carried out at a temperature that is less than 350° C.
Claim 4
Dependent Claim 23 words
The process of claim 2, wherein the sufficient sinter operation is carried out at a temperature in the range of 350° C.-500° C.
Claim 5
Dependent Claim 17 words
The process of claim 3, wherein the sufficient sinter operation is carried out at substantially 400° C.
Claim 6
Dependent Claim 15 words
The process of claim 1, wherein the integrated circuit comprises a dynamic random access memory.
Claim 7
Dependent Claim 32 words
The process of claim 1, wherein the insufficient sinter operation is carried out at a temperature that will not cause a substantial decrease in the interface trap density in the integrated circuit.
Claim 8
Dependent Claim 32 words
The process of claim 1, wherein the sufficient sinter operation is carried out at a temperature that is at a level that will cause a substantial decrease in the interface trap density.

References Cited (Backward Citations)

US3349474A Cited
US3590477A Cited
US4151007A Cited
US4113514A Cited
US4920077A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-05-07 1999-11-06 2000-05-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-05-07 2003-11-06 2004-05-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-05-07 2007-11-06 2008-05-07 $7700.00 Window Closed / Lapsed

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