Abstract: A semiconductor device has a first diode having a pn junction and a second diode having a combination of a Schottky barrier and a pn junction in a current-passing direction provided side by side in a direction perpendicular to the current-passing direction. When a forward current with a current density J.sub.F is passed into the second diodes, the relation ##EQU1## is established in a forward voltage V.sub.F range of 0.1 (V) to 0.3 (V), where k represents the Boltzmann constant, T represents the absolute temperature, and q represents the quantity of electron charges.

Abstract: A method for fabricating an insulated gate semiconductor device comprises the steps of forming insulated gates on an n.sup.- -layer surface, forming p-well layers in the n.sup.- -layer using the insulated gates as masks, forming phosphosilicate glass layers on the side walls of the insulated gates and diffusing the impurities from the phosphosilicate glass layers into the p-well layers to form n.sup.+ -source layer.

Abstract: Disclosed is a composite semiconductor device which comprises: a second and a third semiconductor regions of a second conductivity type formed in a first semiconductor region of a first conductivity type independently of each other and so as to be exposed on one main surface of a semiconductor substrate; a fourth and a fifth semiconductor regions of the first conductivity type formed in the second semiconductor region independently of each other and so as to be exposed on the one main surface of the semiconductor substrate; a first insulated gate electrode formed on the second semiconductor region located between the fifth and first semiconductor regions and exposed on the one main surface; a second insulated gate electrode formed on the first semiconductor region located between the second and third semiconductor regions and exposed on the one main surface; an electrode which shorts the fourth and third semiconductor regions; another electrode which shorts the second and fifth semiconductor regions; and a fu

Abstract: In a light-activated semiconductor device wherein a light-activated semiconductor element accommodated in a package is driven by a light signal fed from an external light source into the package through an optical guide, the optical guide comprises a first portion passing through the package and a second portion for optically coupling the first portion and the light-activated element.