A method is disclosed for promoting the formation of uniform platelets in a monocrystalline semiconductor donor substrate by irradiating the monocrystalline semiconductor donor substrate with light. The photon-absorption assisted platelet formation process leads to uniformly distributed platelets with minimum built-in stress that promote the formation a well-defined cleave-plane in the subsequent layer transfer process.

The present disclosure provides a wafer annealing method, including: preparing a wafer, the wafer includes a plurality of regions concentrically disposed on the wafer; heating the plurality of regions, the heating process includes a plurality of heating stages, each of the heating stages has a different heating rate, temperatures of the plurality of regions vary in each of the heating stages; performing heat preservation on the plurality of regions; and cooling the plurality of regions through blowing nitrogen. The wafer annealing method can improve the electrical uniformity of the wafer.

The present invention provides a monocrystalline SiC substrate with an asymmetric shape for enhancing substrate stiffness against thermal induced deformations, the substrate comprising: a main region, and an asymmetric region located at a peripheral region of the substrate and adjacent to the main region, wherein the asymmetric region is inclined inwards, relative to the main region, to provide an asymmetric shape to the substrate. The present invention also provides a method of producing one or more substrates with an asymmetric shape, comprising: performing a multi-wire sawing process in which one or more substrates are cut with an wire-sawing web from an ingot placed on a stage, and cutting the one or more substrates with the asymmetric shape by controlling a relative movement between the wire-sawing web and the stage, the relative movement causing the wire-sawing web to describe a non-linear sawing path across the ingot to cut the asymmetric shape.

Embodiments of the present disclosure include techniques related to techniques for processing materials for manufacture of group-III metal nitride and gallium based substrates. More specifically, embodiments of the disclosure include techniques for growing large area substrates using a combination of processing techniques. Merely by way of example, the disclosure can be applied to growing crystals of GaN, AlN, InN, InGaN, AlGaN, and AlInGaN, and others for manufacture of bulk or patterned substrates. Such bulk or patterned substrates can be used for a variety of applications including optoelectronic and electronic devices, lasers, light emitting diodes, solar cells, photo electrochemical water splitting and hydrogen generation, photodetectors, integrated circuits, and transistors, and others.

A silicon wafer is provided in which a dopant is phosphorus, resistivity is 1.2 mΩ.Math.cm or less, and carbon concentration is 3.5×10.sup.15 atoms/cm.sup.3 or more. The carbon concentration is decreased by 10% or more near a surface of the silicon wafer compared with a center-depth of the silicon wafer.

A silicon wafer is provided in which a dopant is phosphorus, resistivity is from 0.5 mΩ.Math.cm to 1.2 mΩ.Math.cm, and carbon concentration is 3.0×10.sup.16 atoms/cm.sup.3 or more. The carbon concentration is decreased by 10% or more near a surface of the silicon wafer compared with a center-depth of the silicon wafer.

A method for preparing a single crystal silicon ingot and a wafer sliced therefrom are provided. The ingots and wafers comprise nitrogen at a concentration of at least about 1×10.sup.14 atoms/cm.sup.3 and/or germanium at a concentration of at least about 1×10.sup.19 atoms/cm.sup.3, interstitial oxygen at a concentration of less than about 6 ppma, and a resistivity of at least about 1000 ohm cm.

A doped SiOC liquid starting material provides a p-type polymer derived ceramic SiC crystalline materials, including boules and wafers. P-type SiC electronic devices. Low resistivity SiC crystals, wafers and boules, having phosphorous as a dopant. Polymer derived ceramic doped SiC shaped charge source materials for vapor deposition growth of doped SiC crystals.

A doped SiOC liquid starting material provides a p-type polymer derived ceramic SiC crystalline materials, including boules and wafers. P-type SiC electronic devices. Low resistivity SiC crystals, wafers and boules, having phosphorous as a dopant. Polymer derived ceramic doped SiC shaped charge source materials for vapor deposition growth of doped SiC crystals.

The present invention addresses the problem of providing a novel SiC substrate production method. The SiC substrate production method according to the present invention comprises an etching step S10 of etching a SiC base substrate 10, a crystal growth step S20 of growing a SiC substrate layer 13 on the SiC base substrate 10 to produce a SiC substrate body 20, and a peeling step S30 of peeling at least a portion of the SiC substrate body 20 to produce a SiC substrate 30, the method being characterized in that each of the etching step S10 and the crystal growth step S20 is a step of arranging the SiC base substrate 10 and a SiC material 40 so as to face each other and heating the SiC base substrate 10 and the SiC material 40 so as to form a temperature gradient between the SiC base substrate 10 and the SiC material 40.