Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
187 words
An insulated-gate field-effect transistor comprising a semiconductor body having a surface-adjoining source region of one conductivity type which is surrounded in the body by a surface-adjoining second region of the opposite conductivity type, the second region being surrounded in the body by a surface-adjoining third region which is of said one conductivity type and is associated with the transistor drain, an insulating layer on a part of the second region, and a conductive layer on said insulating layer to form an insulated gate of the transistor for capacitively controlling in said part of the second region a conductive channel between the source region and a first part of the third region, characterized in that the third region has a surface-adjoining second part which is remote from the first part, in that an electrode layer extends on said second part of the third region and is connected to said second region, and in that there is provided between said electrode layer and the second part of the third region a Schottky junction having a lower forward voltage drop that the p-n junction between the second and third regions.
Claim 2
Dependent Claim
187 words
An insulated-gate field-effect transistor comprising a semiconductor body having a surface-adjoining source region of one conductivity type which is surrounded in the body by a surface-adjoining second region of the opposite conductivity type, the second region being surrounded in the body by a surface-adjoining third region which is of said one conductivity type and is associated with the transistor drain, an insulating layer on a part of the second region, and a conductive layer on said insulating layer to form an insulated gate of the transistor for capacitively controlling in said part of the second region a conductive channel between the source region and a first part of the third region, characterized in that the third region has a surface-adjoining second part which is remote from the first part, in that an electrode layer extends on said second part of the third region and is connected to said second region, and in that there is provided between said electrode layer and the second part of the third region a Schottky junction having a lower forward voltage drop that the p-n junction between the second and third regions.
Claim 3
Dependent Claim
32 words
A transistor as claimed in claim 1, further characterized in that the second part of the third region has a lower conductivity type determining doping concentration than the second and source regions.
Claim 4
Dependent Claim
50 words
A transistor as claimed in claim 1 or claim 2, further characterized in that the second part of the third region is laterally bounded by the second region of opposite conductivity type which extends around the periphery of the Schottky junction to form a guard ring for the Schottky junction.
Claim 5
Dependent Claim
28 words
A transistor as claimed in claim 3, further characterized in that the source region in the second region also extends around the second part of the third region.
Claim 6
Dependent Claim
50 words
A transistor as claimed in claim 1, further characterized in that the extent and doping concentration profile of the second region between the source region and the second part of the third region are substantially the same as between the source region and the first part of the third region.
Claim 7
Dependent Claim
59 words
A transistor as claimed in claim 1, further characterized in that a source electrode which contacts the source region also extends laterally over the second region and the second part of the third region to form an electrical connection between the second and source regions and to form said electrode layer on the second part of the third region.
Claim 8
Dependent Claim
22 words
A transistor as claimed in claim 1, further characterized in that the electrode layer forms a Schottky junction with the second region.
Claim 9
Dependent Claim
29 words
A transistor as claimed in claim 1, further characterized in that the Schottky junction with the second part of the third region is formed by the said electrode layer.
Claim 10
Dependent Claim
47 words
A transistor as claimed in claim 6, further characterized in that the Schottky junction with the second part of the third region is formed by the said electrode layer, that the third and source regions are of N type silicon, and the source electrode is of aluminum.
Claim 11
Dependent Claim
51 words
A transistor as claimed in claim 1, further characterized in that the insulated gate is present on a part of the second region at a major surface of the body, and in that said source region and the first and second parts of said third region also adjoin said major surface.
Claim 12
Dependent Claim
45 words
A transistor as claimed in claim 1, further characterized in that the insulated gate is present on a part of the second region at a groove in a major surface of the body, and in that at least said source region adjoins said major surface.