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.

The present invention provides an efficient heat treatment such as activation treatment of impurities on a substrate such as a thick silicon wafer with large heat capacity by laser annealing.

Provided is a laser annealing apparatus 1 for heat-treating a surface of a substrate 30 comprising: a pulse oscillation laser source 10 which generates a pulse laser with gentle rise time and long pulse width; a continuous wave laser source 20 which generates a near-infrared laser for assisting annealing; optical systems 12, 22 which shape and guide beams 15, 25 of the two types of lasers respectively so as to irradiate the surface of the substrate 30 therewith; and a moving device 3 which moves the substrate 30 relatively to the laser beams 15, 25 to allow scanning of the combined irradiation of the two types of laser beams. According to this apparatus, deep activation of impurities can be performed in a thick semiconductor substrate with large heat capacity while securing sufficient light penetration depth and thermal diffusion length therefor.

A gate controlled semiconductor device comprising a collector region of a first conductivity type; a drift region of a second conductivity type located over the collector region; a body region of a first conductivity type located over the drift region; at least one first contact region of a second conductivity type located above the body region and having a higher doping concentration compared to the body region. The device further comprises at least one second contact region of a first conductivity type located laterally adjacent to the at least one first contact region, the at least one second contact region having a higher doping concentration than the body region. The device further comprises at least one active trench extending from a surface into the drift region, in which the at least one first contact region adjoins the at least one active trench so that, in use, a channel region is formed along said at least one active trench and within the body region. The at least one active trench comprises: two vertical sidewalls and a bottom surface between the two vertical sidewalls; and an insulation layer along the vertical side walls and the bottom surface, wherein the insulation layer along at least one vertical side wall comprises different thicknesses; at least one auxiliary trench extending from the surface into the drift region. The at least one auxiliary trench comprises: two vertical sidewalls and a bottom surface between the two vertical sidewalls; and an insulation layer along the vertical side walls and the bottom surface, wherein the insulation layer along at least one vertical side wall comprises a constant thickness.

Method for manufacturing an insulated gate bipolar transistor, which includes a drift layer of a first conductivity type between an emitter side, at which a gate and emitter electrode are arranged, and a collector side, at which a collector electrode is arranged including steps: providing a substrate of a second conductivity type, applying a dopant of the first conductivity type on the first side, creating a drift layer of the first conductivity type on the first layer, diffusing the ions such that a buffer layer is created, having a higher doping concentration than the drift layer, creating a base layer of the second conductivity type on the drift layer, creating an emitter layer of the first conductivity type on the base layer, thinning the substrate on the second side such that the remaining part of the substrate forms a collector layer.

A semiconductor device includes a first main electrode terminal and second main electrode terminal disposed on the principal surface of a semiconductor substrate so as to be spaced from one another, an insulating film formed on the principal surface of the semiconductor substrate, and a thin film resistance layer. One end side of the thin film resistance layer is connected to the first main electrode terminal and the other end side of the thin film resistance layer is connected to the second main electrode terminal, the thin film resistance layer being spirally formed on the insulating film in such a way as to surround the first main electrode terminal. The thin film resistance layer extends while oscillating in a thickness direction of the semiconductor substrate.

There are disclosed herein various implementations of a bipolar semiconductor device with sub-cathode enhancement regions. Such a bipolar semiconductor device includes a drift region having a first conductivity type situated over an anode layer having a second conductivity type opposite the first conductivity type. The bipolar semiconductor device also includes first and second depletion trenches, each having a depletion electrode. In addition, the bipolar semiconductor device includes a first control trench situated between the first and second depletion trenches, the first control trench extending into the drift region and being adjacent to cathode diffusions. An enhancement region having the first conductivity type is localized in the drift region between the first control trench and one or both of the first and second depletion trenches. In one implementation, the bipolar semiconductor device may be an insulated-gate bipolar transistor (IGBT).

An impurity of a second conductivity type is selectively doped in a surface of a semiconductor substrate of a first conductivity type to form doped regions. A portion of a surface of the doped regions is covered by a heat insulating film. At least a remaining portion of the surface of the doped regions is covered by an absorbing film and the doped regions are heated through the absorbing film, enabling an impurity region of the second conductivity type to be formed having two or more of the doped regions that have a same impurity concentration and differing carrier concentrations.

A semiconductor device includes first and second electrodes and a silicon carbide layer located between the first and second electrodes. A plurality of gate electrodes is interposed between the first electrode and the silicon carbide layer and extends in a first direction. The silicon carbide layer includes a plurality of spaced apart openings having sidewalls and a base which extend inwardly between the gate electrodes, a first region containing a second conductivity type impurity extending around and under the openings, and a second region containing a second conductivity type impurity interposed between the portion of the first region extending under the base of the openings. The concentration of the second conductivity type impurity is greater in the second region than in the first region. The silicon carbide layer includes a third region containing a first conductivity type impurity extending inwardly of the first region from the sidewall of the openings.

A semiconductor device includes a substrate having a first conductivity type, a high-voltage well having a second conductivity type and formed in the substrate, a drift region formed in the high-voltage well, a drain region formed in the high-voltage well and spaced apart from the drift region, and a buried region having the first conductivity type formed in the high-voltage well between the drift region and the drain region.

A linear active cell region is formed from a plurality of divided active cell regions arranged apart from each other in a second direction (y direction). The linear hole collector cell region is formed from a plurality of divided hole collector cell regions arranged apart from each other in the second direction (y direction). A P-type floating region is formed in a semiconductor substrate between the linear active cell region and the linear hole collector cell region adjacent to each other in a first direction (x direction), between the divided active cell regions adjacent to each other in the second direction (y direction), and between the divided hole collector cell regions adjacent to each other in the second direction (y direction).