Perovskite oxide field effect transistors comprise perovskite oxide materials for the channel, source, drain, and gate oxide regions. The source and drain regions are doped with a higher concentration of n-type or p-type dopants (depending on whether the transistor is an n-type or p-type transistor) than the dopant concentration in the channel region to minimize Schottky barrier height between the source and drain regions and the source and drain metal contact and contact resistance.

A semiconductor device includes a first region in which a drift, base, and accumulation regions are stacked. Transistor cells are each provided partially in the first region and include at least one trench extending into the drift region. A second region includes a well region provided on an edge termination region side surrounding the first region. A third region of a predetermined width is between the first and second regions, inside of which the transistor cells are partially provided. A bottom region is provided in the first region, adjacent to a bottom of the trench, and between the accumulation and drift regions, the bottom region not extending into the third region, its upper surface located below the base region's lower surface; and first and second electrodes configured to flow current therebetween. The bottom region is spaced apart from the base region by the accumulation region in the depth direction.

An object of the present invention is to provide a semiconductor device capable of eliminating unevenness of current distribution in a plane. A semiconductor device according to the present invention is a semiconductor device including a transistor cell region where a plurality of transistor cells is arranged on a semiconductor substrate, the semiconductor device including an electrode pad which is arranged avoiding the transistor cell region on the semiconductor substrate and is electrically connected to a one-side current electrode of each of the cells, in which the transistor cell region contains a plurality of regions each of which has a different current drive capability from each other depending on a distance from the electrode pad.

An HBT includes a semiconductor substrate having first and second principal surfaces opposite each other; and a collector layer, a base layer, and an emitter layer stacked in this order on the first principal surface side of the semiconductor substrate. The collector layer includes a first semiconductor layer with metal particles dispersed therein, the metal particles each formed by a plurality of metal atoms bonded with each other.

Some embodiments include a transistor having a drain region and a source region. A conductive gate is between the source and drain regions. First channel material is between the gate and the source region. The first channel material is spaced from the gate by one or more insulative materials. Second channel material is between the first channel material and the source region, and directly contacts the source region. The first and second channel materials are transition metal chalcogenide. One of the source and drain regions is a hole reservoir region and the other is an electron reservoir region. Tunnel dielectric material may be between the first and second channel materials.

A semiconductor device provided herein includes: a fourth region of a p-type being in contact with a lower end of the gate trench; a termination trench provided in the front surface in a range outside the second region; a lower end p-type region of the p-type being in contact with a lower end of the termination trench; a lateral p-type region of the p-type being in contact with a lateral surface of the termination trench on an outer circumferential side, connected to the lower end p-type region, and exposed on the front surface; and a plurality of guard ring regions provided on the outer circumferential side with respect to the lateral p-type region and exposed on the front surface.

A semiconductor device includes a first fin structure for a first fin field effect transistor (PET). The first fin structure includes a first base layer protruding from a substrate, a first intermediate layer disposed over the first base layer and a first channel layer disposed over the first intermediate layer. The first fin structure further includes a first protective layer made of a material that prevents an underlying layer from oxidation. The first channel layer is made of SiGe, the first intermediate layer includes a first semiconductor (e.g., SiGe) layer disposed over the first base layer and a second semiconductor layer (e.g., Si) disposed over the first semiconductor layer. The first protective layer covers side walls of the first base layer, side walls of the first semiconductor layer and side walls of the second semiconductor layer.

A semiconductor device includes an element portion and a gate pad portion on the same wide gap semiconductor substrate. The element portion includes a first trench structure having a plurality of first protective trenches and first buried layers formed deeper than gate trenches. The gate pad portion includes a second trench structure having a plurality of second protective trenches and second buried layers. The second trench structure is either one of a structure where the second trench structure includes: a p-type second semiconductor region and a second buried layer made of a conductor or a structure where the second trench structure includes a second buried layer formed of a metal layer which forms a Schottky contact. The second buried layer is electrically connected with the source electrode layer.

A source region of a MOSFET includes a source contact region connected to a source electrode, a source extension region adjacent to a channel region of a well region, and a source resistance control region provided between the source extension region and the source contact region. The source resistance control region includes a low concentration source resistance control region which has an impurity concentration lower than that of the source contact region or the source extension region and a high concentration source resistance control region which is formed between the well region and the low concentration source resistance control region and has an impurity concentration higher than that of the low concentration source resistance control region.

The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.