A 3D semiconductor device including: a first level including a first single crystal layer and first transistors, which each include a single crystal channel; a first metal layer with an overlaying second metal layer; a second level including second transistors, overlaying the first level; a third level including third transistors, overlaying the second level; a fourth level including fourth transistors, overlaying the third level, where the second level includes first memory cells, where each of the first memory cells includes at least one of the second transistors, where the fourth level includes second memory cells, where each of the second memory cells includes at least one of the fourth transistors, where the first level includes memory control circuits, where second memory cells include at least four memory arrays, each of the four memory arrays are independently controlled, and at least one of the second transistors includes a metal gate.

A semiconductor film, a sheet like object, and a semiconductor device are provided that have inhibited semiconductor properties, particularly leakage current, and excellent withstand voltage and heat dissipation. A crystalline semiconductor film or a sheet like object includes a corundum structured oxide semiconductor as a major component, wherein the film has a film thickness of 1 m or more. Particularly, the semiconductor film or the object includes a semiconductor component of oxide of one or more selected from gallium, indium, and aluminum as a major component. A semiconductor device has a semiconductor structure including the semiconductor film or the object.

Provided is a crystalline multilayer structure having good semiconductor properties. In particular, the crystalline multilayer structure has good electrical properties as follows: the controllability of conductivity is good; and vertical conduction is possible. A crystalline multilayer structure includes a metal layer containing a uniaxially oriented metal as a major component and a semiconductor layer disposed directly on the metal layer or with another layer therebetween and containing a crystalline oxide semiconductor as a major component. The crystalline oxide semiconductor contains one or more metals selected from gallium, indium, and aluminum and is uniaxially oriented.

Presented is a lateral fin static induction transistor including a semi conductive substrate, source and drain regions extending from an optional buffer layer of same or varied thickness supported by the semi conductive substrate, a semi conductive channel electrically coupling the source region to the drain region of the transistor, a portion of the semi conductive channel being a fin and having a face covered by a gated structure, thereby defining a gated channel within the semi conductive channel, the semi conductive channel further including a drift region electrically coupling the gated channel to the drain region of the transistor.

A silicon carbide (SiC) static induction transistor (SIT) includes a source, a gate disposed over the source and receiving a control signal, a drain disposed over the recessed gate and generating an output signal, an epitaxial pattern disposed between the source and the drain and including a protruding portion, and a gate bus electrically coupled to the gate and including carbon. A method of forming an SiC SIT transistor device includes providing a substrate including a source doped with dopants of a first conductivity type, forming an epitaxial pattern including a protruding portion over the source, forming a recessed gate over the source, forming a gate bus over the recessed gate, forming a drain over the gate bus and the epitaxial pattern, and forming a first heatsink over the drain.