US3745425A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor devices
Assignee: US Philips Corp
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Filing: 1966-06-17
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Granted: 1973-07-10
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Expires: 1986-06-17
Abstract
Abstract An insulated gate field effect device comprising opposite conductivity type source and drain electrodes in a one-type substrate, forming source and drain P-N junctions. The drain P-N junction is back-biased forming a depletion layer extending into the substrate. To diminish the width of the depletion layer, an additional zone of the same conductivity type as the drain but of higher resistivity is provided contiguous with the drain offering the advantages of low capacitance and low depletion layer width as a function of voltage.
Inventors
- 👤 J Beale
- 👤 A Beer
- 👤 T Klein
- 👤 N Murphy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:36
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/601; H10D30/603; H10D62/00; H10D62/10; H10D62/17; H10D62/213; H10D62/221; H10D62/235; H10D62/299; H10D62/307; H10D62/314; H10D99/00; H10W; H10W15/00; H10W15/01; Y; Y10; Y10S; Y10S148/00; Y10S148/049; Y10S148/05; Y10S148/145
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
160 words
An insulated gate field effect device comprising a semiconductive body including a substrate portion of one conductivity type material having a relatively high resistivity, at least two spaced surface zones of the opposite conductivity type in the body constituting source and drain electrodes and forming P-N junctions wIth the substrate portion, a dielectric layer on the surface of the body and covering a portion of the body between the surface zones of opposite conductivity type, a conductive layer on the surface of the dielectric layer, and ohmic connections to the conductive layer and to the two spaced surface zones for reverse biasing the P-N junction at the drain electrode, wherein the improvement comprises within the body contiguous with the surface zone constituting the drain electrode and extending toward the other surface zone a region of material having said opposite type conductivity but an active impurity concentration lower than that of and thus a resistivity higher than that of the substrate.
Claim 2
Dependent Claim
160 words
An insulated gate field effect device comprising a semiconductive body including a substrate portion of one conductivity type material having a relatively high resistivity, at least two spaced surface zones of the opposite conductivity type in the body constituting source and drain electrodes and forming P-N junctions wIth the substrate portion, a dielectric layer on the surface of the body and covering a portion of the body between the surface zones of opposite conductivity type, a conductive layer on the surface of the dielectric layer, and ohmic connections to the conductive layer and to the two spaced surface zones for reverse biasing the P-N junction at the drain electrode, wherein the improvement comprises within the body contiguous with the surface zone constituting the drain electrode and extending toward the other surface zone a region of material having said opposite type conductivity but an active impurity concentration lower than that of and thus a resistivity higher than that of the substrate.
Claim 3
Dependent Claim
37 words
A device as set forth in claim 1 wherein said opposite type higher resistivity region surrounds the drain zone on all sides and extends to a greater depth in the body than that of the drain zone.
Claim 4
Dependent Claim
200 words
An insulated gate field effect device comprising a semiconductive body including a surface portion of one conductivity type material, at least two spaced zones of the opposite conductivity type in the body constituting source and drain electrodes and forming P-N junctions with the one-type surface portion to contain a channel region, said source and drain having a lower resistivity than that of the one-type surface portion, a dielectric layer on the surface of the body and covering a portion of the body between the zones of opposite conductivity type, a conductive layer on the surface of the dielectric layer, and ohmic connections to the conductive layer and to the two spaced zones for reverse biasing the P-N junction at the drain electrode, wherein the improvement comprises within the body contiguous with the zone constituting the drain electrode and extending toward but spaced from the other constituting the source a further region of material having said opposite type conductivity but an active impurity concentration which is lower than that of and thus a resistivity higher than that of the one-type surface portion to thereby extend the drain P-N junction to the interface between the further region and the one-type surface portion.
Claim 5
Dependent Claim
200 words
An insulated gate field effect device comprising a semiconductive body including a surface portion of one conductivity type material, at least two spaced zones of the opposite conductivity type in the body constituting source and drain electrodes and forming P-N junctions with the one-type surface portion to contain a channel region, said source and drain having a lower resistivity than that of the one-type surface portion, a dielectric layer on the surface of the body and covering a portion of the body between the zones of opposite conductivity type, a conductive layer on the surface of the dielectric layer, and ohmic connections to the conductive layer and to the two spaced zones for reverse biasing the P-N junction at the drain electrode, wherein the improvement comprises within the body contiguous with the zone constituting the drain electrode and extending toward but spaced from the other constituting the source a further region of material having said opposite type conductivity but an active impurity concentration which is lower than that of and thus a resistivity higher than that of the one-type surface portion to thereby extend the drain P-N junction to the interface between the further region and the one-type surface portion.
Claim 6
Dependent Claim
26 words
A device as set forth in claim 3 wherein said opposite type further region completely separates the drain from the source and the one-type surface portion.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |