Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
169 words
A semiconductor device comprising first and second semiconductor electrode regions (2, 3) separated by a conduction channel (5) in a surface layer (4) of a semiconductor substrate (1), inner gate electrode means (7; 7A, 7B) lying over a central portion of the conduction channel (5) and separated (Dl) by insulating material from the surface layer (4) of the substrate and an outer gate electrode (8) extending completely over the conduction channel (5) and separated (D2) by insulating material from both the conduction channel (5) and the inner gate electrode means (7; 7A, 7B), the device being characterised by the form, size and disposition of the inner gate electrode means (7; 7A, 7B) and the disposition of the outer gate electrode (8) being such that by individually biasing the inner gate electrode means (7; 7A, 7B) and the outer gate electrode (8) with respect to the substrate (1) resonant transmission of electric current can occur through the conduction channel (5) between the first and second semiconductor electrode regions (2, 3).
Claim 2
Dependent Claim
169 words
A semiconductor device comprising first and second semiconductor electrode regions (2, 3) separated by a conduction channel (5) in a surface layer (4) of a semiconductor substrate (1), inner gate electrode means (7; 7A, 7B) lying over a central portion of the conduction channel (5) and separated (Dl) by insulating material from the surface layer (4) of the substrate and an outer gate electrode (8) extending completely over the conduction channel (5) and separated (D2) by insulating material from both the conduction channel (5) and the inner gate electrode means (7; 7A, 7B), the device being characterised by the form, size and disposition of the inner gate electrode means (7; 7A, 7B) and the disposition of the outer gate electrode (8) being such that by individually biasing the inner gate electrode means (7; 7A, 7B) and the outer gate electrode (8) with respect to the substrate (1) resonant transmission of electric current can occur through the conduction channel (5) between the first and second semiconductor electrode regions (2, 3).
Claim 3
Dependent Claim
16 words
A semiconductor device as claimed in claim 1, in which the semiconductor substrate consists of silicon.
Claim 4
Dependent Claim
37 words
A semiconductor device as claimed in claim 1, in which the semiconductor substrate consists of GaAs and the insulating material between the conduction channel, the inner gate electrode means and the outer gate electrode consists of GaAlAs.
Claim 5
Dependent Claim
51 words
A semiconductor device as claimed in any preceding claim, in which the inner gate electrode means consists of a single electrode having a dimension in a direction parallel to the conduction channel of the same order as the mean free path length of an electrical charge carrier in the conduction channel.
Claim 6
Dependent Claim
32 words
A semiconductor device as claimed in claim 4, in which the single 0 gate electrode has a dimension of from 100 to 200 A in the direction parallel to the conduction channel.
Claim 7
Dependent Claim
66 words
A semiconductor device as claimed in claim 4 or claim 5, in which the insulating material between the inner gate electrode means and 0 the conduction channel is from 100 to 200 A thick and the insulating material between the outer gate electrode and the conduction channel is approximately twice as thick as the insulating material between the inner gate electrode means and the conduction channel.
Claim 8
Dependent Claim
74 words
A semiconductor device as claimed in claim 1, in which the inner gate electrode means consists of at least two closely spaced electrodes and in which the thickness of the insulating material between the outer gate electrode and the portions of the conduction channel other than the central portion thereof is substantially equal to the thickness of the insulating material between the inner gate electrode means and the central portion of the conduction channel.
Claim 9
Dependent Claim
90 words
A semiconductor device as claimed in claim 7, in which the inner gate electrode means is produced by forming a step in the insulating material over the conduction channel at the intended location of the inner gate electrode means, edge depositing a masking material against the step in the insulating material, vertically etching away the insulating material except where it is protected by the masking material so as to form a mesa in the insulating material, and edge depositing conductive material on each side of the mesa of insulating material.
Claim 10
Dependent Claim
71 words
A circuit including a semiconductor device as claimed in any preceding claim and a source of a first bias voltage connected to the inner gate electrode means and a source of a second bias voltage connected to the outer gate electrode, the first and second bias voltages being such that the bias applied to the inner gate electrode means enhances the effect of the bias applied to the outer gate electrode.
Claim 11
Dependent Claim
74 words
A circuit including a semiconductor device as claimed in any of claims 1 to 8, and a source of a first bias voltage connected to the inner gate electrode means and a source of a second bias voltage connected to the outer gate electrode, the first and second bias voltages being such that the bias applied to the inner gate electrode means opposes the effect of the bias applied to the outer gate electrode.