Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
138 words
In a lateral transistor comprised of two regions of a second conductivity type, which constitute the emitter region and the collector region, incorporated into the surface of a semiconductor region of a first conductivity type, with the portion of the semiconductor region of the first conductivity type located between said two regions consituting the active base region of said transistor; the improvement wherein: said active base region includes a buried semiconductor zone which is disposed below and spaced from said surface and extends to said emitter and collector region, with said buried semiconductor zone containing additional counterdoping impurities relative to the conductivity of the remaining surrounding portions of said active base region, thus concentrating the minority charge carriers in the active base region at a distance from the semiconductor surface between the emitter region and the collector region.
Claim 2
Dependent Claim
138 words
In a lateral transistor comprised of two regions of a second conductivity type, which constitute the emitter region and the collector region, incorporated into the surface of a semiconductor region of a first conductivity type, with the portion of the semiconductor region of the first conductivity type located between said two regions consituting the active base region of said transistor; the improvement wherein: said active base region includes a buried semiconductor zone which is disposed below and spaced from said surface and extends to said emitter and collector region, with said buried semiconductor zone containing additional counterdoping impurities relative to the conductivity of the remaining surrounding portions of said active base region, thus concentrating the minority charge carriers in the active base region at a distance from the semiconductor surface between the emitter region and the collector region.
Claim 3
Dependent Claim
36 words
A lateral transistor as defined in claim 1 wherein said buried semiconductor zone is of the first conductivity type with its doping concentration being substantially reduced relative to the remaining surrounding portion of said base region.
Claim 4
Dependent Claim
35 words
A lateral transistor as defined in claim 1 wherein said buried semiconductor zone is of the second conductivity type, but is so weakly doped that it is not in the normally on state (depletion mode).
Claim 5
Dependent Claim
16 words
A lateral transistor as defined in claim 1 wherein said transistor is a pnp lateral transistor.
Claim 6
Dependent Claim
48 words
A lateral transistor as defined in claim 1 wherein said buried semiconductor zone is spaced approximately 0.3 μm from said semiconductor surface, reaches a penetration depth of approximately 0.6 μm from said surface, and has a doping concentration of between 10 14 and 10 16 atoms/cm 3 .
Claim 7
Dependent Claim
35 words
A lateral transistor as defined in claim 1 wherein said active base region is covered at said semiconductor surface with a passivation layer on which an electrode layer connected to the emitter contact is arranged.
Claim 8
Dependent Claim
31 words
A lateral transistor as defined in claim 6 wherein said electrode layer consists of conductive polycrystalline silicon and said passivation layer arranged thereunder is composed of silicon dioxide or silicon nitride.
Claim 9
Dependent Claim
34 words
A lateral transistor as defined in claim 4 wherein said pnp lateral transistor is arranged together with CMOS field-effect transistors and npn bipolar transistors on a semiconductor substrate which is common to all components.