US5506167A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making a high resistance drain junction resistor in a SRAM
Assignee: United Microelectronics Corp
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Filing: 1995-04-13
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Granted: 1996-04-09
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Expires: 2015-04-13
Abstract
Abstract An improved SRAM resistor structure having implanted therein ions of an material in the surface layer of a drain junction region juxtaposed to an overlying metal contact layer providing the benefits of high resistance, low energy consumption, a single ion implantation step in an easily controlled process while producing a precise resistance desired and a method of making the SRAM resistor structure.
Inventors
- 👤 Hwi-Huang Chen
- 👤 Gary Hong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:44
CPC Classifications
H; H10; H10B; H10B10/00; H10B10/15; Y; Y10; Y10S; Y10S438/00; Y10S438/934
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
95 words
A method of making a high resistance drain junction resistor on an SRAM chip by an implantation process comprising the steps of: providing a semiconductor substrate having a source junction region, a drain junction region and a gate region, photomasking and etching for an insulating layer and a contact region, photomasking for an implantation such that a photoresist layer covers regions outside of the drain junction, implanting ions of a material into the drain junction region at a suitable energy and dosage level to form a high resistance drain junction resistor, and removing the photoresist.
Claim 2
Independent Claim
95 words
A method of making a high resistance drain junction resistor on an SRAM chip by an implantation process comprising the steps of: providing a semiconductor substrate having a source junction region, a drain junction region and a gate region, photomasking and etching for an insulating layer and a contact region, photomasking for an implantation such that a photoresist layer covers regions outside of the drain junction, implanting ions of a material into the drain junction region at a suitable energy and dosage level to form a high resistance drain junction resistor, and removing the photoresist.
Claim 3
Dependent Claim
32 words
A method according to claim 1 further comprises after said photoresist removal step, a metal layer deposition step, a photomasking step, an etching step, a photoresist removal step and an alloying step.
Claim 4
Dependent Claim
13 words
A method according to claim 1, wherein said material implanted is Si ion.
Claim 5
Dependent Claim
13 words
A method according to claim 1, wherein said material implanted is Ar ion.
Claim 6
Dependent Claim
23 words
A method according to claim 1, wherein said material is implanted at an energy level between about 60 KeV to about 100 KeV.
Claim 7
Dependent Claim
27 words
A method according to claim 1, wherein said material is implanted at a dosage between about 0.5×10 16 /cm 2 and about 5×10 16 /cm 2 .
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-04-09 | 1999-10-09 | 2000-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-04-09 | 2003-10-09 | 2004-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-04-09 | 2007-10-09 | 2008-04-09 | $7700.00 | Window Closed / Lapsed |