Provided is an indium phosphide substrate, a semiconductor epitaxial wafer, and a method for producing an indium phosphide substrate, which can satisfactorily suppress warpage of the back surface of the substrate. The indium phosphide substrate includes a main surface for forming an epitaxial crystal layer and a back surface opposite to the main surface, wherein the back surface has a WARP value of 3.5 μm or less, as measured with the back surface of the indium phosphide substrate facing upward.

Provided is an indium phosphide substrate, a semiconductor epitaxial wafer, and a method for producing an indium phosphide substrate, which can satisfactorily suppress warpage of the back surface of the substrate. The indium phosphide substrate includes a main surface for forming an epitaxial crystal layer and a back surface opposite to the main surface, wherein the back surface has a BOW value of −2.0 to 2.0 μm, as measured with the back surface of the indium phosphide substrate facing upward.

Provided is a method for manufacturing a thin SiC wafer by which a SiC wafer is thinned using a method without generating crack or the like, the method in which polishing after adjusting the thickness of the SiC wafer can be omitted. The method for manufacturing the thin SiC wafer 40 includes a thinning step. In the thinning step, the thickness of the SiC wafer 40 can be decreased to 100 μm or less by performing the Si vapor pressure etching in which the surface of the SiC wafer 40 is etched by heating the SiC wafer 40 after cutting out of an ingot 4 under Si vapor pressure.

A wafer manufacturing method for manufacturing a wafer from an ingot includes forming a peeling layer within the ingot by positioning a condensing point at a depth corresponding to the thickness of the wafer to be produced, and irradiating the ingot with a first laser beam, forming a character, a number, or a mark representing information regarding resistivity in or on the ingot by positioning a condensing point in a region in which devices are not to be formed and irradiating the ingot with a second laser beam, and dividing the ingot with the peeling layer as a starting point.

A method for manufacturing a substrate wafer 100 includes providing a device wafer (110) having a first side (111) and a second side (112); subjecting the device wafer (110) to a first high temperature process for reducing the oxygen content of the device wafer (110) at least in a region (112a) at the second side (112); bonding the second side (112) of the device wafer (110) to a first side (121) of a carrier wafer (120) to form a substrate wafer (100); processing the first side (101) of the substrate wafer (100) to reduce the thickness of the device wafer (110); subjecting the substrate wafer (100) to a second high temperature process for reducing the oxygen content at least of the device wafer (110); and at least partially integrating at least one semiconductor component (140) into the device wafer (110) after the second high temperature process.

A semiconductor device manufacturing method is provided. In a semiconductor wafer prepared, the width of a dicing line is larger than a cut region to be diced with a dicing blade, a first chip forming region and a second chip forming region are adjacent and have the dicing line therebetween, some of the pads are formed on a first chip forming region side, and the remaining pads are formed on a second chip forming region side. The semiconductor wafer is diced with the dicing blade in such manner that, when the some of the pads are diced, a part of the dicing blade on the second chip forming region side does not abut the some of the pads, and, when the remaining pads are diced, a part of the dicing blade on the first one chip forming region side does not abut the remaining pads.

A semiconductor ingot is sliced to obtain a semiconductor slice with a front side surface and a rear side surface parallel to the front side surface. A passivation layer is formed directly on at least one of the front side surface and the rear side surface. A barrier layer including least one of silicon carbide, a ternary nitride, and a ternary carbide is formed on the rear side surface.

A silicon carbide substrate has a first main surface, and a second main surface opposite to the first main surface. A region including at least one main surface of the first and second main surfaces is made of single-crystal silicon carbide. In the one main surface, sulfur atoms are present at not less than 60×10.sup.10 atoms/cm.sup.2 and not more than 2000×10.sup.10 atoms/cm.sup.2, and carbon atoms as an impurity are present at not less than 3 at % and not more than 25 at %. Thereby, a silicon carbide substrate having a stable surface, a semiconductor device using the substrate, and methods for manufacturing them can be provided.

A method of producing a silicon wafer includes: a laser mark printing step of printing a laser mark having a plurality of dots on a silicon wafer; an etching step of performing etching on at least a laser-mark printed region in a surface of the silicon wafer; and a polishing step of performing polishing on both surfaces of the silicon wafer having been subjected to the etching step. In the laser mark printing step, each of the plurality of dots is formed by a first step of irradiating a predetermined position on a periphery of the silicon wafer with laser light of a first beam diameter thereby forming a first portion of the dot and a second step of irradiating the predetermined position with laser light of a second beam diameter that is smaller than the first beam diameter thereby forming a second portion of the dot.

A silicon carbide substrate is a silicon carbide substrate including: a first main surface, a shape of the first main surface before the orientation flat is provided being a circle. An average value of LTVs of a plurality of first square regions of a plurality of square regions is less than or equal to 0.75 μm, the plurality of first square regions being disposed in a form of a ring on an outermost side with respect to the center of the circle so as to form an outermost periphery when the central region of the first main surface is divided into the plurality of square regions to provide a largest number of square regions, each of the square regions exactly forming a square having each side of 5 mm.