A semiconductor structure includes the first semiconductor stack and the second semiconductor stack formed over the first region and the second region of a substrate, respectively. The first and second semiconductor stacks extend in the first direction and are spaced apart from each other in the second direction. Each of the first semiconductor stack and the second semiconductor stack includes channel layers and a gate structure. The channel layers are formed above the substrate and are spaced apart from each other in the third direction. The gate structure includes the gate dielectric layers formed around the respective channel layers, and the gate electrode layer formed on the gate dielectric layers to surround the channel layers. The number of channel layers in the first semiconductor stack is different from the number of channel layers in the second semiconductor stack.

A monolithic optoelectronic integrated circuit is provided, including: a substrate including photonic integrated device region and a peripheral circuit region; a first GaN-based multi-quantum well optoelectronic PN-junction device including a first P-type ohmic contact electrode and a first N-type ohmic contact electrode; and a first GaN-based field-effect transistor, where the first GaN-based field-effect transistor includes a first gate dielectric layer disposed on the surface of the substrate and having a first recess, a first gate filled within the first recess, and a first source and a first drain that are disposed the opposite sides of the first gate, where the first source is electrically connected to the first P-type ohmic contact electrode, the first drain is configured to be electrically connected to a first potential.

A method for manufacturing a vertical JFET includes providing a III-nitride substrate having a first conductivity type and forming a first III-nitride layer coupled to the III-nitride substrate. The first III-nitride layer is characterized by a first dopant concentration and the first conductivity type. The method also includes forming a plurality of trenches within the first III-nitride layer and epitaxially regrowing a second III-nitride structure in the trenches. The second III-nitride structure is characterized by a second conductivity type. The method further includes forming a plurality of III-nitride fins, each coupled to the first III-nitride layer, wherein the plurality of III-nitride fins are separated by one of a plurality of recess regions, and epitaxially regrowing a III-nitride gate layer in the recess regions. The III-nitride gate layer is coupled to the second III-nitride structure and the III-nitride gate layer is characterized by the second conductivity type.

A semiconductor structure includes: a channel layer; an active layer over the channel layer, wherein the active layer is configured to form a two-dimensional electron gas (2DEG) to be formed in the channel layer along an interface between the channel layer and the active layer; a gate electrode over a top surface of the active layer; and a source/drain electrode over the top surface of the active layer; wherein the active layer includes a first layer and a second layer sequentially disposed therein from the top surface to a bottom surface of the active layer, and the first layer possesses a higher aluminum (Al) atom concentration compared to the second layer. An HEMT structure and an associated method are also disclosed.

Embodiments of the invention include nanowire and nanoribbon transistors and methods of forming such transistors. According to an embodiment, a method for forming a microelectronic device may include forming a multi-layer stack within a trench formed in a shallow trench isolation (STI) layer. The multi-layer stack may comprise at least a channel layer, a release layer formed below the channel layer, and a buffer layer formed below the channel layer. The STI layer may be recessed so that a top surface of the STI layer is below a top surface of the release layer. The exposed release layer from below the channel layer by selectively etching away the release layer relative to the channel layer.

A field effect transistor (FET) device includes a substrate, a gate structure over the substrate, a channel region under the gate structure, the channel region including a first semiconductor material, and a second semiconductor material interposed between the first semiconductor material and the substrate. The second semiconductor material is different from the first semiconductor material. An interface of the second semiconductor material with the first semiconductor material has facets. A surface of the second semiconductor material interfacing with the substrate is non-planar.

Techniques are disclosed for an integrated circuit including a ferroelectric gate stack including a ferroelectric layer, an interfacial oxide layer, and a gate electrode. The ferroelectric layer can be voltage activated to switch between two ferroelectric states. Employing such a ferroelectric layer provides a reduction in leakage current in an off-state and provides an increase in charge in an on-state. The interfacial oxide layer can be formed between the ferroelectric layer and the gate electrode. Alternatively, the ferroelectric layer can be formed between the interfacial oxide layer and the gate electrode.

A method for manufacturing a dynamic random access memory device includes providing a semiconductor substrate and forming a highly doped diffusion region in a surface of the semiconductor substrate. A wordline structure is then deposited on the surface of the semiconductor substrate, where the wordline structure includes an electrically conductive gate layer. An opening is further formed in the wordline structure, where the opening is located at a first end of and extending to the highly doped diffusion region. A semiconductor pillar is then formed in the opening by selective epitaxial growth. An end of the semiconductor pillar is then doped and the doped end is connected with a memory element.

A vertical metal oxide semiconductor field effect transistor (MOSFET) and a method for forming a vertical MOSFET is presented. The MOSFET comprises: a top contact; a bottom contact; a nanowire (602) forming a charge transport channel between the top contact and the bottom contact; and a wrap-around gate (650) enclosing the nanowire (602) circumference, the wrap-around gate (650) having an extension spanning over a portion of the nanowire (602) in a longitudinal direction of the nanowire (602), wherein the wrap-around gate (650) comprises a gate portion (614) and a field plate portion (616) for controlling a charge transport in the charge transport channel, and wherein the field plate portion (616) is arranged at a first radial distance (636) from the center of the nanowire (602) and the gate portion (614) is arranged at a second radial distance (634) from the center of the nanowire (602); characterized in that the first radial distance (636) is larger than the second radial distance (634).

A method and vertical FET device fabricated in GaN or other suitable material. The device has a selective area implant region comprising an activated impurity configured from a bottom portion of a recessed regions, and substantially free from ion implant damage by using an annealing process. A gate region is configured from the selective area implant region, and each of the recessed regions is characterized by a depth configured to physically separate an n+ type source region and the p-type gate region such that a low reverse leakage gate-source p-n junction is achieved. An extended drain region is configured from a portion of an n− type GaN region underlying the recessed regions. An n+ GaN region is formed by epitaxial growth directly overlying the backside region of the GaN substrate and a backside drain contact region configured from the n+ type GaN region overlying the backside region.