Semiconductor devices and methods of forming the same include forming slanted dielectric structures from a first dielectric material on a substrate, with gaps between adjacent slanted dielectric structures. A first semiconductor layer is grown from the substrate, using a first semiconductor material, including a lower portion that fills the gaps and an upper portion above the first dielectric material. The lower portion of the first semiconductor layer is replaced with additional dielectric material.

A method for producing a semiconductor chip (100) is provided, in which, during a growth process for growing a first semiconductor layer (1), an inhomogeneous lateral temperature distribution is created along at least one direction of extent of the growing first semiconductor layer (1), such that a lateral variation of a material composition of the first semiconductor layer (1) is produced. A semiconductor chip (100) is additionally provided.

A method is provided for fabricating a semiconductor structure. The method includes providing a bottom substrate having a first region and a second region, and forming a trench in the first region by patterning the bottom substrate. The method also includes forming an insulation layer in the trench in the first region, wherein the insulation layer exposes part of side surface of the trench, and forming a top substrate on the exposed side surface of the trench and the insulation layer. Further, the method includes forming a first fin portion in the first region, and forming a gate structure crossing the first fin portion, wherein the gate structure covers part of side and top surfaces of the first fin portion.

A semiconductor device includes a supporting substrate, an insulating film formed in a first region over the supporting substrate, a first semiconductor layer formed over the insulating film, a first epitaxial layer formed in an opening of the insulating film in a second region over the supporting substrate, an element isolation region formed between the first semiconductor layer and the first epitaxial layer, and a semiconductor element formed over each of the first semiconductor layer in the first region and the first epitaxial layer in the second region. The first semiconductor layer and the first epitaxial layer is spaced apart from each other by 5 μm or more.

Techniques are disclosed for forming a heterojunction bipolar transistor (HBT) that includes a laterally grown epitaxial (LEO) base layer that is disposed between corresponding emitter and collector layers. Laterally growing the base layer of the HBT improves electrical and physical contact between electrical contacts to associated portions of the HBT device (e.g., a collector). By improving the quality of electrical and physical contact between a layer of an HBT device and corresponding electrical contacts, integrated circuits using HBTs are better able to operate at gigahertz frequency switching rates used for modern wireless communications.

Techniques are disclosed for gallium nitride (GaN) oxide isolation and formation of GaN transistor structures on a substrate. In some cases, the GaN transistor structures can be used for system-on-chip integration of high-voltage GaN front-end radio frequency (RF) switches on a bulk silicon substrate. The techniques can include, for example, forming multiple fins in a substrate, depositing the GaN layer on the fins, oxidizing at least a portion of each fin in a gap below the GaN layer, and forming one or more transistors on and/or from the GaN layer. In some cases, the GaN layer is a plurality of GaN islands, each island corresponding to a given fin. The techniques can be used to form various non-planar isolated GaN transistor architectures having a relatively small form factor, low on-state resistance, and low off-state leakage, in some cases.

Some embodiments of the present technology simplify the process of producing SOI wafers significantly compared to traditional methods. Furthermore, various embodiments provide a route for the integration of perovskite transition metal oxide thin films with different properties into SOI wafers. As such films display a wide array of novel electronic, magnetic, and optical phenomena, their integration into technologically-relevant SOI wafers will likely allow for the construction of a wide array of novel devices.

A fabrication method of an integrated circuit semiconductor device includes: forming a plurality of low dielectric pattern apart from each other on a substrate, the plurality of low dielectric pattern having a lower dielectric constant than the substrate; after forming the low dielectric pattern, forming a flow layer to bury the low dielectric pattern on the substrate; forming an epitaxial layer on the flow layer; and forming a transistor in the substrate comprising the low dielectric pattern buried by the flow layer and in the epitaxial layer.

The present disclosure relates to semiconductor structures and, more particularly, to oxidized cavity structures within and under semiconductor devices and methods of manufacture. The structure includes: a substrate material; active devices over the substrate material; an oxidized trench structure extending into the substrate and surrounding the active devices; and one or more oxidized cavity structures extending from the oxidized trench structure and formed in the substrate material under the active devices.

Embodiments herein disclose a method providing deposition of Gadolinium Oxide (Gd.sub.2O.sub.3) on a semiconductor substrate. The method comprises of selecting, in an RF-sputter system, a predefined substrate and depositing, in an Ar-plasma struck, the Gd.sub.2O.sub.3, over the predefined substrate to obtain a layer of the Gd.sub.2O.sub.3 over the predefined substrate. The Gd.sub.2O.sub.3 is grown epitaxially over the predefined substrate. The method further provides performing, annealing, of the layer of the Gd.sub.2O.sub.3 over the predefined substrate at a predefined temperature for a predefined time and obtaining, a layer of the Gd.sub.2O.sub.3, over the predefined substrate. Embodiment also provides a method for fabricating Semiconductor on Insulator Substrate (SIS).