Embodiments of semiconductor assemblies, and related integrated circuit devices and techniques, are disclosed herein. In some embodiments, a semiconductor assembly may include a flexible substrate, a first barrier formed of a first transition metal dichalcogenide (TMD) material, a transistor channel formed of a second TMD material, and a second barrier formed of a third TMD material. The first barrier may be disposed between the transistor channel and the flexible substrate, the transistor channel may be disposed between the second barrier and the first barrier, and a bandgap of the transistor channel may be less than a bandgap of the first barrier and less than a bandgap of the second barrier. Other embodiments may be disclosed and/or claimed.

A junction field effect transistor (JFET) comprises an insulating carrier substrate, a base semiconductor substrate formed on the insulating carrier substrate and a gate region formed on the base semiconductor substrate. The gate region forms a junction with the base semiconductor substrate. The JFET further comprises a first source/drain region formed on the base semiconductor substrate and located on a first side of the gate region and a second source/drain region formed on the base semiconductor substrate and located on a second side of the gate region. A gate stack is deposited on the gate region, a first source/drain stack is deposited on the first source/drain region and a second source/drain stack is deposited on the second source/drain region. At least one of the gate stack, first source/drain stack and second source/drain stack overlaps onto another one of the gate stack, first source/drain stack and second source/drain stack.

Device architectures based on trapping and de-trapping holes or electrons and/or recombination of both types of carriers are obtained by carrier trapping either in near-interface deep ambipolar states or in quantum wells/dots, either serving as ambipolar traps in semiconductor layers or in gate dielectric/barrier layers. In either case, the potential barrier for trapping is small and retention is provided by carrier confinement in the deep trap states and/or quantum wells/dots. The device architectures are usable as three terminal or two terminal devices.

A high electron mobility transistor (HEMT) device with a highly resistive layer co-doped with carbon (C) and a donor-type impurity and a method for making the HEMT device is disclosed. In one embodiment, the HEMT device includes a substrate, the highly resistive layer co-doped with C and the donor-type impurity formed above the substrate, a channel layer formed above the highly resistive layer, and a barrier layer formed above the channel layer. In one embodiment, the highly resistive layer comprises gallium nitride (GaN). In one embodiment, the donor-type impurity is silicon (Si). In another embodiment, the donor-type impurity is oxygen (O).

A junction field effect transistor (JFET) comprises an insulating carrier substrate, a base semiconductor substrate formed on the insulating carrier substrate and a gate region formed on the base semiconductor substrate. The gate region forms a junction with the base semiconductor substrate. The JFET further comprises a first source/drain region formed on the base semiconductor substrate and located on a first side of the gate region and a second source/drain region formed on the base semiconductor substrate and located on a second side of the gate region. A gate stack is deposited on the gate region, a first source/drain stack is deposited on the first source/drain region and a second source/drain stack is deposited on the second source/drain region. At least one of the gate stack, first source/drain stack and second source/drain stack overlaps onto another one of the gate stack, first source/drain stack and second source/drain stack.

An integrated circuit device includes first and second fin-type active regions having different conductive type channel regions, a first device isolation layer covering both sidewalls of the first fin-type active region, and a second device isolation layer covering both sidewalls of the second fin-type active region. The first device isolation layer and the second device isolation layer have different stack structures. To manufacture the integrated circuit device, the first device isolation layer covering both sidewalls of the first fin-type active region and the second device isolation layer covering both sidewalls of the second fin-type active region are formed after the first fin-type active region and the second fin-type active region are formed. The first device isolation layer and the second device isolation layer are formed to have different stack structure.

A method for fabricating a semiconductor device may include receiving a gated substrate comprising a substrate with a channel layer and a gate structure formed thereon, over-etching the channel layer to expose an extension region below the gate structure, epitaxially growing a halo layer on the exposed extension region using a first in-situ dopant and epitaxially growing a source or drain on the halo layer using a second in-situ dopant, wherein the first in-situ dopant and the second in-situ dopant are of opposite doping polarity. Using an opposite doping polarity may provide an energy band barrier for the semiconductor device and reduce leakage current. A corresponding apparatus is also disclosed herein.

A JFET having vertical and horizontal channel elements may be made from a semiconductor material such as silicon carbide using a first mask for multiple implantations to form a horizontal planar JFET region comprising a lower gate, a horizontal channel, and an upper gate, all above a drift region resting on a drain substrate region, such that the gates and horizontal channel are self-aligned with the same outer size and outer shape in plan view. A second mask may be used to create a vertical channel region abutting the horizontal channel region. The horizontal channel and vertical channel may each have multiple layers with varying doping concentrations. Angled implantations may use through the first mask to implant portions of the vertical channel regions. The window of the second mask may partially overlap the horizontal JFET region to insure abutment of the vertical and horizontal channel regions.

Techniques related to III-N transistors having self aligned gates, systems incorporating such transistors, and methods for forming them are discussed. Such transistors include a polarization layer between a raised source and a raised drain, a gate between the source and drain and over the polarization layer, and lateral epitaxial overgrowths over the source and drain and having and opening therebetween such that at least a portion of the gate adjacent to the polarization layer is aligned with the opening.

Methods of forming a semiconductor device include forming a dielectric layer on a Group III-nitride semiconductor layer, selectively removing portions of the dielectric layer over spaced apart source and drain regions of the semiconductor layer, implanting ions having a first conductivity type directly into the source and drain regions of the semiconductor layer, annealing the semiconductor layer and the dielectric layer to activate the implanted ions, and forming metal contacts on the source and drain regions of the semiconductor layer.