A semiconductor multi-layer substrate includes a substrate made of Si and a multi-layer semiconductor layer. The multi-layer semiconductor layer includes an active layer made of a nitride semiconductor, a first warp control layer being formed between the substrate and the active layer and giving a predetermined warp to the substrate, and a second warp control layer made of a nitride semiconductor of which amount of an increase in a warp per a unit thickness is smaller than an amount of increase in the warp per a unit thickness of the first warp control layer. A total thickness of the multi-layer semiconductor layer is equal to or larger than 4 m.

A method of fabricating a multi-layer epitaxial buffer layer stack for transistors includes depositing a buffer stack on a substrate. A first voided Group IIIA-N layer is deposited on the substrate, and a first essentially void-free Group IIIA-N layer is then deposited on the first voided Group IIIA-N layer. A first high roughness Group IIIA-N layer is deposited on the first essentially void-free Group IIIA-N layer, and a first essentially smooth Group IIIA-N layer is deposited on the first high roughness Group IIIA-N layer. At least one Group IIIA-N surface layer is then deposited on the first essentially smooth Group IIIA-N layer.

FinFETs and methods of forming finFETs are described. According to some embodiments, a structure includes a channel region, first and second source/drain regions, a dielectric layer, and a gate electrode. The channel region includes semiconductor layers above a substrate. Each of the semiconductor layers is separated from neighboring ones of the semiconductor layers, and each of the semiconductor layers has first and second sidewalls. The first and second sidewalls are aligned along a first and second plane, respectively, extending perpendicularly to the substrate. The first and second source/drain regions are disposed on opposite sides of the channel region. The semiconductor layers extend from the first source/drain region to the second source/drain region. The dielectric layer contacts the first and second sidewalls of the semiconductor layers, and the dielectric layer extends into a region between the first plane and the second plane. The gate electrode is over the dielectric layer.

Various nanostructures, including silicon nanowires and encapsulated silicon nanoislands, and methods of making the nanostructures are provided. The methods can include providing a fin structure extending above a substrate, wherein the fin structure has at least one silicon layer and at least two silicon:germanium alloy (SiGe) layers that define sidewalls of the fin structure; and annealing the fin structure in oxygen to form a silicon nanowire assembly. The silicon nanowire assembly can include a silicon nanowire, a SiGe matrix surrounding the silicon nanowire; and a silicon oxide layer disposed on the SiGe matrix. The annealing can be, for example, at a temperature between 800 C. and 1000 C. for five minutes to sixty minutes. The silicon nanowire can have a long axis extending along the fin axis, with perpendicular first and second dimensions extending less than 50 nm along directions perpendicular to the fin axis.

A superlattice cell that includes Group IV elements is repeated multiple times so as to form the superlattice. Each superlattice cell has multiple ordered atomic planes that are parallel to one another. At least two of the atomic planes in the superlattice cell have different chemical compositions. One or more of the atomic planes in the superlattice cell one or more components selected from the group consisting of carbon, tin, and lead. These superlattices make a variety of applications including, but not limited to, transistors, light sensors, and light sources.

Semiconductor devices having group III-V material active regions and graded gate dielectrics and methods of fabricating such devices are described. In an example, a semiconductor device includes a group III-V material channel region disposed above a substrate. A gate stack is disposed on the group III-V material channel region. The gate stack includes a graded high-k gate dielectric layer disposed directly between the III-V material channel region and a gate electrode. The graded high-k gate dielectric layer has a lower dielectric constant proximate the III-V material channel region and has a higher dielectric constant proximate the gate electrode. Source/drain regions are disposed on either side of the gate stack.

The present invention is directed to a fabrication method of a semiconductor multilayer structure. By utilizing the indium-containing catalyst and/or gallium-containing catalyst, the aluminum migration can be enhanced to increase quality and flatness of the aluminum contained nitride buffer layer. Furthermore, the costs and energy consumption can be reduced too.

A solution for designing and/or fabricating a structure including a quantum well and an adjacent barrier is provided. A target band discontinuity between the quantum well and the adjacent barrier is selected to coincide with an activation energy of a dopant for the quantum well and/or barrier. For example, a target valence band discontinuity can be selected such that a dopant energy level of a dopant in the adjacent barrier coincides with a valence energy band edge for the quantum well and/or a ground state energy for free carriers in a valence energy band for the quantum well. Additionally, a target doping level for the quantum well and/or adjacent barrier can be selected to facilitate a real space transfer of holes across the barrier. The quantum well and the adjacent barrier can be formed such that the actual band discontinuity and/or actual doping level(s) correspond to the relevant target(s).

Embodiments of an apparatus and methods for providing three-dimensional complementary metal oxide semiconductor devices comprising modulation doped transistors are generally described herein. Other embodiments may be described and claimed, which may include forming a modulation doped heterostructure, comprising forming an active portion having a first bandgap and forming a delta doped portion having a second bandgap.

A method of manufacturing ZnO-containing semiconductor structure includes steps of: (a) forming a subsidiary lamination, including alternately laminating at least two periods of active oxygen layers and ZnO-containing semiconductor layers doped with at least one species of group 3B element; (b) alternately laminating said subsidiary lamination and AgO layer, sandwiching an active oxygen layer, to form lamination structure; and (c) carrying out annealing in atmosphere in which active oxygen exists and pressure is below 10.sup.2 Pa, intermittently irradiating oxygen radical beam on a surface of said lamination structure, forming a p-type ZnO-containing semiconductor structure co-doped with said group 3B element and Ag.