A method of removing a substrate, comprising: forming a growth restrict mask with a plurality of striped opening areas directly or indirectly upon a GaN-based substrate; and growing a plurality of semiconductor layers upon the GaN-based substrate using the growth restrict mask, such that the growth extends in a direction parallel to the striped opening areas of the growth restrict mask, and growth is stopped before the semiconductor layers coalesce, thereby resulting in island-like semiconductor layers. A device is processed for each of the island-like semiconductor layers. Etching is performed until at least a part of the growth restrict mask is exposed. The devices are then bonded to a support substrate. The GaN-based substrate is removed from the devices by a wet etching technique that at least partially dissolves the growth restrict mask. The GaN substrate that is removed then can be recycled.

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 semiconductor structure for a DRAM is described having multiple layers of arrays of memory cells. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Select transistors enable the use of folded bit lines. The memory cells preferably are thyristors. Methods of fabricating the array are described.

A group-III-nitride structure and a manufacturing method thereof are provided. In the manufacturing method, a first mask layer is first formed on a substrate; an uncoalesced second group-III-nitride epitaxial layer is formed by performing a first epitaxial growth with the first mask layer as a mask; and a second mask layer is formed at least on the second group-III-nitride epitaxial layer; a third group-III-nitride epitaxial layer is laterally grown and formed by performing a second epitaxial growth on the second group-III-nitride epitaxial layer with the second mask layer as a mask, where the second group-III-nitride epitaxial layer is coalesced by the third group-III-nitride epitaxial layer; a fourth group-III-nitride epitaxial layer is formed by performing a third epitaxial growth on the third group-III-nitride epitaxial layer.

Disclosed are semiconductor structure embodiments of a semiconductor-on-insulator region on a bulk substrate. The semiconductor-on-insulator region includes an upper semiconductor layer above and physically separated from the substrate by insulator-containing cavities (e.g., by dielectric layer and/or a pocket of trapped air, of trapped gas, or under vacuum) and, optionally, by a lower semiconductor layer. Disclosed method embodiments include forming openings that extend vertically through the upper semiconductor layer, through a sacrificial semiconductor layer and, optionally, through a lower semiconductor layer to the substrate. Then, a selective isotropic etch process is performed to form cavities, which extend laterally off the sides of the openings into the sacrificial semiconductor layer. Depending upon the embodiments, different process steps are further performed to form plugs in at least the upper portions of the openings and insulators (including dielectric layers and/or a pocket of trapped air, of trapped gas or under vacuum) in the cavities.

An epitaxial lateral overgrowth (ELO) of a III-nitride layer is used to cover a growth restrict mask deposited on a substrate, wherein the III-nitride ELO layer is grown with a low V/III ratio of less than 500 resulting in high-speed lateral growth as compared to low-speed vertical growth. The III-nitride ELO layer contains a large amount of impurities, over 1 × 10.sup.18 cm.sup.-3, which result in the III-nitride ELO layer comprising a coloring layer. The coloring layer absorbs light from an active region due to the large amount of impurities. When a bar of device layers is removed from the substrate, at least a portion of the coloring layer is removed from the bar. The elimination of the coloring layer reduces absorption losses, which makes the device characteristics improve.

The subject disclosure relates to high mobility complementary metal-oxide-semiconductor (CMOS) devices and techniques for forming the CMOS devices with fins formed directly on the insulator. According to an embodiment, a method for forming such a high mobility CMOS device can comprise forming, via a first epitaxial growth of a first material, first pillars within first trenches formed within a dielectric layer, wherein the dielectric layer is formed on a silicon substrate, and wherein the first pillars comprise first portions with defects and second portions without the defects. The method can further comprise forming second trenches within a first region of the dielectric layer, and further forming second pillars within the second trenches via a second epitaxial growth of one or more second materials using the second portions of the first pillars as seeds for the second epitaxial growth.

A semiconductor device including a nanostructure, including a planar layer of a III-nitride semiconductor crystal, which layer includes an array of epitaxially grown nanowire structures, and semiconductor material which is redistributed from said nanowire structures in a reformation step after epitaxial growth, arranged to fill out a spacing between the nanowire structures, where the array of nanowire structures and the semiconductor material form a coherent layer.

The disclosure provides a manufacturing method of a nitride semiconductor structure. The method includes the followings. Multiple island structures separated from each other are formed on a sapphire substrate. A GaN layer is formed on the island structures. A silicon substrate is bonded to a surface of the GaN layer facing away from the sapphire substrate. The sapphire substrate, the island structures, and a first sublayer of the GaN layer are removed. The first sublayer of the GaN layer has multiple voids, and the voids are located between the island structures.

Exemplary semiconductor processing methods may include providing a silicon-containing precursor to a processing region of a semiconductor processing chamber. A substrate may be disposed within the processing region of the semiconductor processing chamber. The substrate may include a nitrogen-containing nucleation layer deposited on the substrate. The methods may include forming a silicon-containing material on at least a first portion of the nitrogen-containing nucleation layer. The methods may include forming a second layer of material on at least a second portion of the nitrogen-containing nucleation layer. The methods may include forming a masking layer on a portion of the second layer of material. The masking layer may cover less than or about 90% of the second layer of material. The methods may include growing the second layer of material through the masking layer. The methods may include coalescing the second layer of material above the masking layer.