Semiconductor device manufacturing: process – Making field effect device having pair of active regions... – Having insulated gate
Reexamination Certificate
2001-04-27
2004-06-08
Trinh, Michael (Department: 2822)
Semiconductor device manufacturing: process
Making field effect device having pair of active regions...
Having insulated gate
C438S237000, C438S238000, C438S563000, C438S586000
Reexamination Certificate
active
06746907
ABSTRACT:
TECHNICAL FIELD
This invention relates to methods of forming field effect transistors, and to field effect transistor circuitry.
BACKGROUND OF THE INVENTION
It is desirable in transistors to be able to drive high currents. Driving high currents can enhance a transistor's operating performance including its operating speed. In field effect transistors (FETs), current flow is primarily conducted by way of the drain-to-source current I
ds
. While higher drive currents can be achieved by building wider FET devices, tradeoffs are made in valuable wafer real estate. Larger devices also typically have larger capacitances which can adversely impact device performance. Also typically, a high I
ds
current in FET devices can result in an increased sub-threshold current leakage. It is desirable in FETs to minimize the sub-threshold current leakage. Accordingly, it is desirable to have the I
ds
ratio of on-state current (I
on
) to off-state current (I
off
) be as high as possible. Such improves sub-threshold device leakage characteristics as well as increases the transistor's operating speed performance.
This invention arose out of concerns associated with improving field effect transistor performance.
SUMMARY OF THE INVENTION
Methods of forming field effect transistors and resultant field effect transistor circuitry are described. In one embodiment, a semiconductive substrate includes a field effect transistor having a body. A first resistive element is received by the substrate and connected between the transistor's gate and the body. A second resistive element is received by the substrate and connected between the body and a reference voltage node. The first and second resistive elements form a voltage divider which is configured to selectively change threshold voltages of the field effect transistor with state changes in the gate voltage. In a preferred embodiment, first and second diode assemblies are positioned over the substrate and connected between the gate and body, and the body and a reference voltage node to provide the voltage divider.
REFERENCES:
patent: 3577019 (1971-05-01), Storm
patent: 4246502 (1981-01-01), Kubinec
patent: 4297721 (1981-10-01), McKenny et al.
patent: 4546401 (1985-10-01), Svedberg
patent: 5250457 (1993-10-01), Dennison
patent: 5268323 (1993-12-01), Fischer et al.
patent: 5317282 (1994-05-01), Quast
patent: 5629536 (1997-05-01), Heminger et al.
patent: 5631187 (1997-05-01), Phipps et al.
patent: 5661329 (1997-08-01), Hiramoto et al.
patent: 5681778 (1997-10-01), Manning
patent: 5734175 (1998-03-01), Taniguchi
patent: 5744842 (1998-04-01), Ker
patent: 5847597 (1998-12-01), Ooishi et al.
patent: 6107664 (2000-08-01), Quoirin et al.
patent: 6114197 (2000-09-01), Hsu
patent: 6121665 (2000-09-01), Gonzalez et al.
patent: 6271067 (2001-08-01), Gonzalez et al.
Physics of Semiconductor Devices; S.M. Sze; pp. 505-512; © 1969.
Solid State Electronic Devices; Ben G. Streetman; pp. 298-300; © 1972.
“The New IEEE Standard Dictionary of Electrical and Electronics Terms—Fifth Edition,” ©1993, p. 1467 (3 pages total).
Gonzalez Fernando
Mouli Chandra
John P.S. Wells St.
Trinh Michael
LandOfFree
Methods of forming field effect transistors and field effect... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Methods of forming field effect transistors and field effect..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods of forming field effect transistors and field effect... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3364772