US5371394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double implanted laterally diffused MOS device and method thereof
Assignee: NXP USA Inc
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Filing: 1993-11-15
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Granted: 1994-12-06
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Expires: 2013-11-15
Abstract
Abstract An NMOS transistor has a source and a drain composed of n+ type of semiconductor material. A substrate region composed of a p type of semiconductor material is disposed between the source and the drain. A gate region is disposed above the substrate region and between the source region and the drain region. A first implant region is disposed adjacent to the source region and the gate region. The first implant region is composed of p type of semiconductor material with a first doping concentration. A second implant region is disposed between the first implant region and the substrate. The second implant region is composed of p type of semiconductor material with a second doping concentration. The channel doping profile first and second implant regions is tailored to obtain the optimum internal electric field to maximize device transconductance, while simultaneously controlling the device threshold voltage and punch through characteristics.
Inventors
- 👤 Gordon C. Ma
- 👤 Hassan Pirastehfar
- 👤 Steven J. Adler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:59
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/0221; H10D30/60; H10D30/601; H10D30/0223; H10D30/0227; H10D30/603; H10D62/00; H10D62/10; H10D62/17; H10D62/213; H10D62/221; H10D62/235; H10D62/299; H10D62/307; H10D62/351; H10D62/357; H10D62/364; H10D62/371; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/017
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
100 words
An MOS transistor, comprising: a source region having a first type of semiconductor material; a substrate region having a second type of semiconductor material; a first implant region disposed below said source region and extending up a channel side of said source region, said first implant region having said second type of semiconductor material with a first doping concentration; and a second implant region disposed between said first implant region and said substrate region and extending up a channel side of said source region, said second implant region having said second type of semiconductor material with a second doping concentration.
Claim 2
Dependent Claim
100 words
An MOS transistor, comprising: a source region having a first type of semiconductor material; a substrate region having a second type of semiconductor material; a first implant region disposed below said source region and extending up a channel side of said source region, said first implant region having said second type of semiconductor material with a first doping concentration; and a second implant region disposed between said first implant region and said substrate region and extending up a channel side of said source region, said second implant region having said second type of semiconductor material with a second doping concentration.
Claim 3
Dependent Claim
23 words
The MOS transistor of claim 1 further including a drain region having said first type of semiconductor material disposed above said substrate region.
Claim 4
Dependent Claim
25 words
The MOS transistor of claim 2 further including a gate region disposed above said substrate region and between said source region and said drain region.
Claim 5
Dependent Claim
18 words
The MOS transistor of claim 3 wherein said first type of semiconductor material is n type semiconductor material.
Claim 6
Dependent Claim
18 words
The MOS transistor of claim 4 wherein said second type of semiconductor material is p type semiconductor material.
Claim 7
Independent Claim
108 words
A method of forming a MOS transistor, comprising the steps of: providing a source region having a first type of semiconductor material; providing a substrate region having a second type of semiconductor material; disposing a first implant region below said source region and extending up a channel side of said source region, said first implant region having said second type of semiconductor material with a first doping concentration; and disposing a second implant region between said first implant region and said substrate region and extending up a channel side of source region, said second implant region having said second type of semiconductor material with a second doping concentration.
Claim 8
Independent Claim
108 words
A method of forming a MOS transistor, comprising the steps of: providing a source region having a first type of semiconductor material; providing a substrate region having a second type of semiconductor material; disposing a first implant region below said source region and extending up a channel side of said source region, said first implant region having said second type of semiconductor material with a first doping concentration; and disposing a second implant region between said first implant region and said substrate region and extending up a channel side of source region, said second implant region having said second type of semiconductor material with a second doping concentration.
Claim 9
Dependent Claim
25 words
The method of claim 6 further including the step of disposing a drain region having said first type of semiconductor material above said substrate region.
Claim 10
Dependent Claim
27 words
The method of claim 7 further including the step of disposing a gate region above said substrate region and between said source region and said drain region.
Claim 11
Dependent Claim
17 words
The method of claim 8 wherein said first type of semiconductor material is n type semiconductor material.
Claim 12
Dependent Claim
17 words
The method of claim 9 wherein said second type of semiconductor material is p type semiconductor material.
Claim 13
Dependent Claim
144 words
An NMOS transistor, comprising: a source region having a n+ type of semiconductor material; a drain region having said n+ type of semiconductor material; a substrate region disposed between said source region and said drain region having a p type of semiconductor material; a gate region disposed above said substrate region and between said source region and said drain region; a first implant region disposed below said source region and extending up a channel side of said source region to said gate region, said first implant region having said p type of semiconductor material with a first doping concentration; and a second implant region disposed between said first implant region and said substrate region and extending up to a channel side of source region to said gate region, said second implant region having said p type of semiconductor material with a second doping concentration.
Claim 14
Dependent Claim
144 words
An NMOS transistor, comprising: a source region having a n+ type of semiconductor material; a drain region having said n+ type of semiconductor material; a substrate region disposed between said source region and said drain region having a p type of semiconductor material; a gate region disposed above said substrate region and between said source region and said drain region; a first implant region disposed below said source region and extending up a channel side of said source region to said gate region, said first implant region having said p type of semiconductor material with a first doping concentration; and a second implant region disposed between said first implant region and said substrate region and extending up to a channel side of source region to said gate region, said second implant region having said p type of semiconductor material with a second doping concentration.
References Cited (Backward Citations)
US4994904A
Cited
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