A laser irradiation method of irradiating, with a pulse laser beam, an irradiation object in which an impurity source film is formed on a semiconductor substrate includes: reading fluence per pulse of the pulse laser beam with which a rectangular irradiation region set on the irradiation object is irradiated and the number of irradiation pulses the irradiation region is irradiated, the fluence being equal to or larger than a threshold at or beyond which ablation potentially occurs to the impurity source film when the irradiation object is irradiated with pulses of the pulse laser beam in the irradiation pulse number and smaller than a threshold at or beyond which damage potentially occurs to the surface of the semiconductor substrate; calculating a scanning speed Vdx; and moving the irradiation object at the scanning speed Vdx relative to the irradiation region while irradiating the irradiation region with the pulse laser beam at the repetition frequency f.

A method for thermally processing a substrate having a surface region and a buried region with a pulsed light beam, the substrate presenting an initial temperature-depth profile and the surface region presenting an initial surface temperature, including steps of: illuminating the surface region with a preliminary pulse so that it generates an amount of heat and reaches a predetermined preliminary surface temperature; and illuminating the surface region with a subsequent pulse after a time interval so that it reaches a predetermined subsequent surface temperature. The time interval is determined such that the surface region reaches a predetermined intermediate surface temperature greater than the initial surface temperature, such that during the time interval, the amount of heat is diffused within the substrate down to a predetermined depth so that the substrate presents a predetermined intermediate temperature-depth profile.

A semiconductor structure and a manufacturing method are disclosed. The semiconductor structure includes: a substrate, including a core region and a peripheral region, where a part of the substrate of the core region is provided with a first gate, a first doped region is provided in a part of the substrate at two opposite sides of the first gate, and a dielectric layer is provided on the top surface of the first doped region; a part of the substrate of the peripheral region is provided with a second gate, and a second doped region is provided in a part of the substrate at two opposite sides of the second gate; a first conductive pillar; and a second conductive pillar, where a depth of the second conductive pillar into the second doped region is less than a depth of the first conductive pillar into the first doped region.

The laser doping apparatus may irradiate a predetermined region of a semiconductor material with a pulse laser beam to perform doping. The laser doping apparatus may include: a solution supplying system configured to supply dopant-containing solution to the predetermined region, and a laser system including at least one laser device configured to output the pulse laser beam to be transmitted by the dopant-containing solution, and a time-domain pulse waveform changing apparatus configured to control a time-domain pulse waveform of the pulse laser beam.

When p-type impurities are implanted into a SiC substrate using a laser, controlling the concentration is difficult. A p-type impurity region is formed by a laser in a region where the control of the concentration in the SiC substrate is not necessary almost at all. A SiC semiconductor device having withstanding high voltage is manufactured at a lower temperature process compared to ion implantation process. A method of manufacturing a silicon carbide semiconductor device includes forming, on one main surface of a first conductivity-type silicon carbide substrate, a first conductivity-type drift layer having a lower concentration than that of the silicon carbide substrate; forming, on a front surface side of the drift layer, a second conductivity-type electric field control region by a laser doping technology; forming a Schottky electrode in contact with the drift layer; and forming, on the other main surface of the silicon carbide substrate, a cathode electrode.

A method of defect reduction for a SiC layer includes activating dopants disposed in the SiC layer, depositing a carbon-rich layer on the SiC layer after activating the dopants, tempering the carbon-rich layer so as to form graphite on the SiC layer, and diffusing carbon from the graphite into the SiC layer. Carbon diffused from the graphite fills carbon vacancies in the SiC layer.

A semiconductor device of according to an embodiment of the present disclosure includes a n-type SiC layer; a SiC region provided on the n-type SiC layer and containing H (hydrogen) or D (deuterium) in an amount of 1×10.sup.18 cm.sup.−3 or more and 1×10.sup.22 cm.sup.−3 or less; and a metal layer provided on the SiC region.

The invention solves the problem of depressed SOA of a bipolar junction transistor (BJT) when operated in an open base configuration by integrating in the same semiconductor chip a switchable short between the base and the emitter of the BJT. The switchable short switches between a high resistive value when the collector voltage of the BJT is lower than the base voltage. and a lower resistive value when the collector voltage is higher than the voltage base to effectively lower the BJT current gain (h.sub.FE). The switchable short in one implementation of the invention is in the form of a MOSFET with its gate connected to the BJT collector. The invention further teaches disposing in the integrated circuit chip a junction diode with a breakdown voltage lower than the BVCBO of the BJT. The addition of the junction diode provides a measure of maintaining the effectiveness of the MOSFET as switchable short at a reduced size.

A method of forming a semiconductor device includes forming a trench in a semiconductor body; at least partially filling the trench with a filling material; introducing dopants into a portion of the filling material; and applying a first thermal processing to the semiconductor body to spread the dopants in the filling material along a vertical direction of the filling material by a diffusion process. The vertical doping profile of the dopants within the doped filling material is shaped during the first thermal processing. Additionally, the dopants are substantially confined to within the trench and substantially do not diffuse from the doped filling material into the semiconductor body during the first thermal processing. A second thermal processing is applied to the semiconductor body after the first thermal processing to cause diffusion of the dopants from the doped filling material into the semiconductor body adjoining the trench.

A semiconductor device includes: a semiconductor substrate; a semiconductor layer of a first conductivity type that is deposited on a surface of the semiconductor substrate; a trench that is formed on a surface of the semiconductor layer; an insulating film that covers a bottom surface of the trench and a lateral surface of the trench; a conductive body that fills inside the trench that is covered by the insulating film; a second conductive type region that is formed in the semiconductor layer, is arranged under the trench, and is within a region of the trench in a plan view of the semiconductor substrate; and a metal film that is electrically connected to the conductive body and forms a Schottky barrier with the surface of the semiconductor layer.