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Field effect transistors

Assignee: National Research Development Corp UK
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Filing: 1981-11-25
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Granted: —
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Expires: 2001-11-25
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Abstract

Abstract An FET device comprises a substrate with source and drain regions separated by a gate structure. Between the gate and substrate is an insulator formed of a cubic fluorite structure material that is lattice matched within 1% to the substrate. The insulator may be a group II fluoride such as CayCd 1-y F 2 (O ≤ y≤ 1Sr 2 Ba 1-z F2 (O≤z≤ 1), or Ba x Ca 1-x F 2 (O ≤ x ≤ 1), or an oxide such as Ce0 2 , PbO 2 . The substrate may be a bulk semiconductor or an epitaxial layer such as Si, InP, GaAs, Ga x Al 1-x As, GaSb, InAs, or AlAs.

Inventors

  • 👤 Robin Frederick Charles Farrow
  • 👤 Gordon Robert Jones
  • 👤 Philip William Sullivan

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-23 05:47
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/01342; H10D64/01358; H10D64/60; H10D64/66; H10D64/68; H10D64/691; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6332; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69396; H10P14/69397

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 63 words
A method of manufacturing an FET device comprising the steps of cleaning a substrate under ultra high vacuum conditions, depositing under high vacuum conditions an insulating layer by molecular beam evaporation onto the epitaxial layer, the lattice of insulator and epitaxial layer being substantially matched, providing a gate electrode on the insulating layer, and source and drain regions either side the gate electrode.
Claim 2
Independent Claim 63 words
A method of manufacturing an FET device comprising the steps of cleaning a substrate under ultra high vacuum conditions, depositing under high vacuum conditions an insulating layer by molecular beam evaporation onto the epitaxial layer, the lattice of insulator and epitaxial layer being substantially matched, providing a gate electrode on the insulating layer, and source and drain regions either side the gate electrode.
Claim 3
Dependent Claim 62 words
A field effect transistor device comprising a substrate with source and drain region and a gate arranged between the source and drain region and separated from the substrate by an insulating layer, characterised in that the insulator is a cubic fluorite structure material and that the lattice parameter of the substrate and the insulator are less than 1% different to one another.
Claim 4
Dependent Claim 62 words
A field effect transistor device comprising a substrate with source and drain region and a gate arranged between the source and drain region and separated from the substrate by an insulating layer, characterised in that the insulator is a cubic fluorite structure material and that the lattice parameter of the substrate and the insulator are less than 1% different to one another.
Claim 5
Dependent Claim 14 words
A device according to claim 2 wherein the insulator is a group II fluoride.
Claim 6
Dependent Claim 14 words
A device according to claim 3 wherein the fluoride is selected from the containing
Claim 7
Dependent Claim 12 words
A device according to claim 2 wherein the insulator is an oxide.
Claim 8
Dependent Claim 22 words
A device according to claim 5 wherein the oxide is selected from the group containing CeO 2 , or PbO 2 .
Claim 9
Dependent Claim 27 words
A device according to claim 2 wherein the substrate is selected from the group containing Si, InP, GaAs, Ga x Al 1 As, GaSb, InAs or AlAs.
Claim 10
Dependent Claim 20 words
A device according to claim 7 wherein the substate is an epitaxial layer formed on a supporting semiconductor material base.
Claim 11
Dependent Claim 23 words
A device according to claim 2 wherein the substrate is Si and the insulating material is Ca 0.58 Cd 0.42 F 2 .
Claim 12
Dependent Claim 28 words
A device according to claim 2 wherein the substrate is InP and the insulating material is Sr 0.8 Ba 0.2 F 2 or Ca 0.45 Ba 0.55 F2.
Claim 13
Dependent Claim 22 words
A device according to claim 2 wherein the substrate is GaAs and the insulating material is Ca 0.26 Ba 0.74 F 2

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