Patent US5350933A successfully refreshed from Google Patents.
US5350933A
Expired / Lapsed
US
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Semiconductor CMOS static RAM with overlapping thin film transistors
Assignee: Sony Corp
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Filing: 1991-02-19
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Granted: 1994-09-27
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Expires: 2011-02-19
Abstract
Abstract A pair of load transistors of a flip-flop circuit constituting a memory cell consist of thin film transistors, and channel regions of the pair of load transistors overlap drain regions of the transistors through a gate insulating film. For this reason, a channel length of the load transistor can be sufficiently increased, and a leakage current of the load transistor can be reduced.
Inventors
- 👤 Ikuo Yoshihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:55
CPC Classifications
H; H10; H10B; H10B10/00; H10B10/12; H10B10/125; H10D; H10D84/00; H10D84/80; H10D84/82; H10D84/83; H10D84/85; Y; Y10; Y10S; Y10S257/00; Y10S257/903
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
144 words
A semiconductor memory comprising a memory cell having a flip-flop circuit consisting of a pair of driver transistors of a first conductivity type channel and a pair of load transistors of a second conductivity type channel, and a pair of access transistors, wherein said pair of load transistors of the second conductivity type channel are formed by semiconductor thin films wherein each of the pair of load transistors have a channel region and a drain region such that the drain region of one of said pair of load transistors of the second conductivity type channel overlaps the channel region of the other of the pair of load transistors through a gate insulating film and the drain region of the other of the pair of load transistors overlap the channel region of the one of the pair of load transistors through the gate insulating film.
Claim 2
Dependent Claim
144 words
A semiconductor memory comprising a memory cell having a flip-flop circuit consisting of a pair of driver transistors of a first conductivity type channel and a pair of load transistors of a second conductivity type channel, and a pair of access transistors, wherein said pair of load transistors of the second conductivity type channel are formed by semiconductor thin films wherein each of the pair of load transistors have a channel region and a drain region such that the drain region of one of said pair of load transistors of the second conductivity type channel overlaps the channel region of the other of the pair of load transistors through a gate insulating film and the drain region of the other of the pair of load transistors overlap the channel region of the one of the pair of load transistors through the gate insulating film.
Claim 3
Dependent Claim
40 words
A semiconductor memory according to claim 1, wherein source regions of said pair of load transistors of the second conductivity type channel extend in opposite directions and are connected to power source lines between which the memory cell is located.
Claim 4
Dependent Claim
175 words
A semiconductor memory comprising a memory cell having a flip-flop circuit consisting of a pair of driver transistors of a first conductivity type channel and a pair of load transistors of a second conductivity type channel, and a pair of access transistors, wherein said pair of load transistors of the second conductivity type channel are formed by semiconductor thin films each having a channel region and a drain region such that the drain region of one of said pair of load transistors of the second conductivity type channel overlaps the channel region of the other of the pair of load transistors through a gate insulating film and the drain region of the other of the pair of load transistors overlap the channel region of the one of the pair of load transistors through the gate insulating film; and further wherein widths of said semiconductor thin films of said pair of load transistors of the second conductivity type channel are larger at a portion of said drain region than at a portion of said channel region.
Claim 5
Dependent Claim
175 words
A semiconductor memory comprising a memory cell having a flip-flop circuit consisting of a pair of driver transistors of a first conductivity type channel and a pair of load transistors of a second conductivity type channel, and a pair of access transistors, wherein said pair of load transistors of the second conductivity type channel are formed by semiconductor thin films each having a channel region and a drain region such that the drain region of one of said pair of load transistors of the second conductivity type channel overlaps the channel region of the other of the pair of load transistors through a gate insulating film and the drain region of the other of the pair of load transistors overlap the channel region of the one of the pair of load transistors through the gate insulating film; and further wherein widths of said semiconductor thin films of said pair of load transistors of the second conductivity type channel are larger at a portion of said drain region than at a portion of said channel region.
Claim 6
Dependent Claim
187 words
A semiconductor memory comprising a memory cell having a flip-flop circuit consisting of a pair of driver transistors of a first conductivity type channel and a pair of load transistors of a second conductivity type channel, and a pair of access transistors, wherein said pair of load transistors of the second conductivity type channel are formed by semiconductor thin films wherein each of the pair of load transistors have a channel region and a drain region such that the drain regions of one of said pair of load transistors of the second conductivity type channel overlaps the channel region of the other of the pair of load transistors through a gate insulating film and the drain region of the other of the pair of load transistors overlap the channel region of the one of the pair of load transistors through the gate insulating film, wherein said pair of driver transistors of the first conductivity type channel are formed by semiconductor thin films such that channel regions and drain regions of said pair of driver transistors of the first conductivity type channel overlap through the gate insulating film.
Claim 7
Dependent Claim
187 words
A semiconductor memory comprising a memory cell having a flip-flop circuit consisting of a pair of driver transistors of a first conductivity type channel and a pair of load transistors of a second conductivity type channel, and a pair of access transistors, wherein said pair of load transistors of the second conductivity type channel are formed by semiconductor thin films wherein each of the pair of load transistors have a channel region and a drain region such that the drain regions of one of said pair of load transistors of the second conductivity type channel overlaps the channel region of the other of the pair of load transistors through a gate insulating film and the drain region of the other of the pair of load transistors overlap the channel region of the one of the pair of load transistors through the gate insulating film, wherein said pair of driver transistors of the first conductivity type channel are formed by semiconductor thin films such that channel regions and drain regions of said pair of driver transistors of the first conductivity type channel overlap through the gate insulating film.
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