A method of making a Group III nitride material that includes: providing a substrate; patterning a template on the substrate; depositing a layer of a material comprising aluminum, gallium and nitrogen on the substrate at a temperature; annealing the layer comprising aluminum, gallium and nitrogen; epitaxially growing Distributed Bragg Reflectors to form a structure on the substrate that comprises microcavities; and etching micropillars in the structure for at least 30 seconds with a heated basic solution is described.

Materials containing picocrystalline quantum dots that form artificial atoms are disclosed. The picocrystalline quantum dots (in the form of born icosahedra with a nearly-symmetrical nuclear configuration) can replace corner silicon atoms in a structure that demonstrates both short range and long-range order as determined by x-ray diffraction of actual samples. A novel class of boron-rich compositions that self-assemble from boron, silicon, hydrogen and, optionally, oxygen is also disclosed. The preferred stoichiometric range for the compositions is (B.sub.12H.sub.w).sub.xSi.sub.yO.sub.z with 3≤w≤5, 2≤x≤4, 2≤y≤5 and 0≤z≤3. By varying oxygen content and the presence or absence of a significant impurity such as gold, unique electrical devices can be constructed that improve upon and are compatible with current semiconductor technology.

The present invention provides a preparation method of a gallium nitride single crystal based on a ScAlMgO.sub.4 substrate, comprising following steps: (1) providing a ScAlMgO.sub.4 substrate; (2) growing a buffer layer on a surface of the ScAlMgO.sub.4 substrate; (3) annealing the buffer layer; (4) growing a GaN crystal on the buffer layer; (5) performing cooling, so that the GaN crystal is automatically peeled off from the ScAlMgO.sub.4 substrate. The present invention does not need to use a complex MOCVD process for GaN deposition and preprocessing to make a mask or a separation layer, which effectively reduces production costs; compared with traditional substrates such as sapphire, it has higher quality and a larger radius of curvature, and will not cause a problem of OFFCUT non-uniformity for growing GaN over 4 inches; finally, the present invention can realize continuous growth into a crystal bar with a thickness of more than 5 mm, which further reduces the costs.

The present invention relates to a method for reducing structural damage to the surface of monocrystalline aluminium-nitride substrates, according to which the substrate undergoes thermal treatment in a crucible in an autoclave, during which treatment the aluminum-nitride substrate is sublimated in the damaged regions of the surface of the substrate and is removed. The method is used to prepare the surface of monocrystalline aluminium-nitride (AlN), in particular the aim of the invention is to eliminate, or at least significantly reduce near-surface structural damage to the monocrystalline material caused by mechanical processing. The invention also relates to aluminium-nitride substrates that are treated in this way.

An electrical device includes an aluminum nitride passivation layer for a mercury cadmium telluride (Hg.sub.1-xCd.sub.xTe) (MCT) semiconductor layer of the device. The AlN passivation layer may be an un-textured amorphous-to-polycrystalline film that is deposited onto the surface of the MCT in its as-grown state, or overlying the MCT after the MCT surface has been pre-treated or partially passivated, in this way fully passivating the MCT. The AlN passivation layer may have a coefficient of thermal expansion (CTE) that closely matches the CTE of the MCT layer, thereby reducing strain at an interface to the MCT. The AlN passivation layer may be formed with a neutral inherent (residual) stress, provide mechanical rigidity, and chemical resistance to protect the MCT.

Proposed are a layered compound having indium and phosphide, a nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by K.sub.1-xIn.sub.yP.sub.z (0≤x≤1.0, 0.75≤y≤1.25, 1.25≤z≤1.75).

A method for producing an aligned boron nitride nanotube film includes drying a dispersion containing boron nitride nanotubes, a biopolymer, and a solvent.

The present invention relates to a process for synthesizing indium phosphide by liquid phosphorus injection method, which belongs to the field of semiconductor technology. The method comprises: converting gaseous phosphorus into liquid phosphorus through a condenser, injecting the liquid phosphorus into an indium melt while preventing phosphorus vaporization by randomly delivering a low temperature inert gas, and causing an instantaneous reaction between the liquid phosphorus and the liquid indium melt, so that an indium phosphide melt can be synthesized at a relatively low temperature, with advantages of high efficiency, high purity, precise proportioning, large capacity, aiding in the growth of a phosphorus-rich indium phosphide polycrystal and facilitating the growth of an indium phosphide monocrystal. The method includes the steps of indium cleaning, phosphorus charging, furnace loading, communication of condenser, synthesis, preparation of crystals, etc.

The present invention relates to a process for synthesizing indium phosphide by liquid phosphorus injection method, which belongs to the field of semiconductor technology. The method comprises: converting gaseous phosphorus into liquid phosphorus through a condenser, injecting the liquid phosphorus into an indium melt while preventing phosphorus vaporization by randomly delivering a low temperature inert gas, and causing an instantaneous reaction between the liquid phosphorus and the liquid indium melt, so that an indium phosphide melt can be synthesized at a relatively low temperature, with advantages of high efficiency, high purity, precise proportioning, large capacity, aiding in the growth of a phosphorus-rich indium phosphide polycrystal and facilitating the growth of an indium phosphide monocrystal. The method includes the steps of indium cleaning, phosphorus charging, furnace loading, communication of condenser, synthesis, preparation of crystals, etc.

An epitaxial wafer according to the present disclosure includes: a substrate; a buffer layer formed of a crystal having the composition formula represented by Al.sub.xGa.sub.yIn.sub.zN (x+y+z=1, y>0) on the substrate; a back-barrier layer formed of a crystal having the composition formula represented by Al.sub.xGa.sub.yIn.sub.zN (x+y+z=1, y>0, z>0) on the buffer layer; a channel layer formed of a crystal having the composition formula represented by Al.sub.xGa.sub.yIn.sub.zN (x+y+z=1, y>0) on the back-barrier layer; and an electron-supply layer formed of a crystal having the composition formula represented by Al.sub.xGa.sub.yIn.sub.zN (x+y+z=1, x>0) on the channel layer. The channel layer is constituted with an upper channel layer underneath the electron-supply layer and a lower channel layer on the back-barrier layer, and the lower channel layer has a C concentration higher than the upper channel layer and contains Si.