EP0497216A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
SOI transistor with pocket implant
Assignee: Texas Instruments Inc
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Filing: 1992-01-24
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Granted: —
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Expires: 2012-01-24
Abstract
Abstract A silicon-on-insulator MOS transistor (200) is disclosed that has an implanted region (32) of the same conductivity type as the body underneath one or both of the extended drain and source portions (26) of the drain (24) and the source (23) with and without a BTS contact or a general body contact. With only the pocket implants, the back gate threshold voltage is enhanced to reduce the possibility of back gate current flowing. With the pocket implants and a body contact, the floating body effects are minimized. Due to the BTS contact being located as far into the source as the pocket implant extends, negligible impact is made on the device channel. Ohmic connection between the source and the body is made for example by way of silicidation. <IMAGE>
Inventors
- 👤 Theodore W. Houston
- 👤 Gordon P. Pollack
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 16:23
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0321; H10D30/0323; H10D30/60; H10D30/67; H10D30/6704; H10D30/6708
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
131 words
A field effect transistor formed in a semiconductor layer overlying an insulating film, comprising: a body node portion of a first conductivity type and having first and second sides; a drain region and a source region formed in said semiconductor layer, said drain and source regions being of a second conductivity type, said drain and source regions disposed adjacent said body node portion and at least one of said source and drain including a portion extending towards said body node portion; and a pocket implant of said first conductivity type extending from said body node portion and lying underneath the extended portion of at least one of said drain and source, said pocket being more heavily doped than the said body node portion; a gate electrode overlying said body node portion.
Claim 2
Dependent Claim
23 words
The transistor of Claim 1 wherein a pocket implant lies underneath the extended portion of both the drain region and the source region.
Claim 3
Dependent Claim
29 words
The transistor of Claim 1, wherein said extended drain and source portions are lightly doped drain regions (LDD) of the same conductivity type as the drain and the source.
Claim 4
Dependent Claim
35 words
The transistor of Claim 1, wherein the source side is pocket implanted of the same conductivity type as the body, with a sufficient dose to create a leaky junction between the source and the body.
Claim 5
Dependent Claim
77 words
The transistor of Claim 1, wherein the source side is pocket implanted and there is a BTS contact of the first conductivity type in the source region, adjacent to the pocket implant of the body and the source extension on one side and the source region on the other, extending to the surface of the semiconductor layer of the mesa such that silicidation on the surface of the mesa can connect the source to the body node.
Claim 6
Dependent Claim
70 words
The transistor of Claim 1, wherein the source side is pocket implanted and there is a BTS contact of the first conductivity type in the source region, adjacent to the pocket implant of the body and the source extension on one side and the source region on the other, extending to the surface of the semiconductor layer of the mesa such that some voltage may be applied to the body.
Claim 7
Independent Claim
105 words
A method of fabricating an integrated circuit in a semiconductor layer overlying an insulating film, comprising the steps of: patterning and etching of a mesa from a starting SOI wafer; depositing of a gate oxide layer over the mesa; depositing, patterning and etching of the gate electrode; light doping of said source and drain regions of a first conductivity type; heavy doping of the source and drain regions with a dopant of a second conductivity type; depositing and etching of conformal sidewall oxide; doping source and drain regions with heavy concentrations of a dopant of a first conductivity type; and deposition of the metallization contacts.
Claim 8
Dependent Claim
31 words
The method of Claim 7, wherein said doping steps comprise: implanting dopant ions of said first conductivity type and of said second conductivity type; and annealing to diffuse the implanted ions.
Claim 9
Dependent Claim
132 words
A field effect transistor formed in a semiconductor layer overlying an insulating film, comprising: a body node portion of a first conductivity type and having first and second sides; a drain region and a source region formed in said semiconductor layer, said drain and source regions being of a second conductivity type, said drain and source regions disposed adjacent said body node portion and at least one of said source and drain including a portion extending towards said body node portion; and a pocket implant of said first conductivity type extending from said body node portion and recessed relative to the extended portion of at least one of said drain and source, said pocket being more heavily doped than the said body node portion; a gate electrode overlying said body node portion.
References Cited (Backward Citations)
No citation records indexed.
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