Abstract: A semiconductor device comprises a superlattice semiconductor portion having a plurality of pairs of superlattice semiconductor thin films for forming step differences of band edge energy. The pairs of the thin films are laminated such that parameters which determine the structure of the thin films are monotonically changed in the direction of the lamination of the thin films. Electrodes are disposed to apply an electric field across both ends of the superlattice semiconductor portion. The semiconductor device has a good negative resistance characteristic and a large design freedom of semiconductor device.

Abstract: Planar semiconductor device including a crystalline layer of Ga.sub.x Al.sub.1-x Sb compound semiconductor (0.1<x<0.3) grown on a GaSB substrate and a narrow energy band gap semiconductor grown as an active layer on the crystalline layer and having electrodes formed on the active layer in the planar form.

Abstract: Occurrence of high field domain in the conventional Gunn diode is prevented by covering a solid body such as a semiconductor element partially or wholly by a dielectric member or by a control element such as a metallic layer coupled reactively with the solid body through a dielectric member, whereby a solid state element having a negative differential conductivity is obtained. Such a type of negative-resistance solid state element, together with its various modes of embodimental construction disclosed herein, affords a superior solid state element which is applicable to amplifiers, oscillators, logic memories, and the like of millimeter or submillimeter bands.

Abstract: The invention disclosed relates to a bulk semiconductor device having a semiconductor element exhibiting a negative conductivity under a high electric field and being capable of generating a high electric field domain therein. The semiconductor device includes two ohmic electrodes disposed at opposite ends to apply a bias voltage, at least one means for generating a high electric field domain in the semiconductor device by means applying an input signal to the generating means, at least one means for inhibiting generation of a high electric field domain by means applying another input signal to the inhibiting means, and means for detecting the existence of the high electric field domain in the semiconductor device to produce an output signal.

Abstract: Disclosed is a bulk semiconductor device which employs a semiconductor element exhibiting negative conductivity under a high electric field. Said semiconductor element has at least two regions and at least one bridge portion and each region thereof is connected with the region adjacent thereto by a bridge portion. Means for controlling the lateral spatial growth of a high electric field domain is provided on or near each bridge portion. The growth of a high electric field domain generated in one of the regions into the adjacent region is controlled by applying a signal to said controlling means.