A method for forming a semiconductor device includes incorporating recombination center atoms into a semiconductor substrate. The method further includes, after incorporating the recombination center atoms into the semiconductor substrate, implanting noble gas atoms into a doping region of a diode structure and/or a transistor structure, the doping region being arranged at a surface of the semiconductor substrate.

There is provided a semiconductor device comprising: a semiconductor substrate; an emitter region of a first conductivity type provided inside the semiconductor substrate; a base region of a second conductivity type provided below the emitter region inside the semiconductor substrate; an accumulation region of the first conductivity type provided below the base region inside the semiconductor substrate, and containing hydrogen as an impurity; and a trench portion provided to pass through the emitter region, the base region and the accumulation region from an upper surface of the semiconductor substrate.

There is provided a semiconductor device comprising: a semiconductor substrate; an emitter region of a first conductivity type provided inside the semiconductor substrate; a base region of a second conductivity type provided below the emitter region inside the semiconductor substrate; an accumulation region of the first conductivity type provided below the base region inside the semiconductor substrate, and containing hydrogen as an impurity; and a trench portion provided to pass through the emitter region, the base region and the accumulation region from an upper surface of the semiconductor substrate.

A multilayer composite structure and a method of preparing a multilayer composite structure are provided. The multilayer composite structure comprises a semiconductor handle substrate having a minimum bulk region resistivity of at least about 500 ohm-cm and comprises a region of nitrogen-reacted nanovoids in the front surface region; a silicon dioxide layer on the surface of the semiconductor handle substrate; a dielectric layer in contact with the silicon dioxide layer; and a semiconductor device layer in contact with the dielectric layer.

A method of manufacturing a semiconductor device that includes a semiconductor element. The method includes the steps of providing a semiconductor substrate of a first conductivity type, forming an element structure of the semiconductor element, at a first main surface of the semiconductor substrate, forming a first protective film at a second main surface of the semiconductor substrate, implanting ions in the semiconductor substrate from the second main surface having the first protective film formed thereon, and removing the first protective film.

Provided is a semiconductor epitaxial wafer in which the concentration of hydrogen in a modifying layer can be maintained at a high level and the crystallinity of an epitaxial layer is excellent. A semiconductor epitaxial wafer has a semiconductor wafer, a modifying layer formed in a surface portion of the semiconductor wafer, which modifying layer has hydrogen contained as a solid solution in the semiconductor wafer, and an epitaxial layer formed on the modifying layer. The concentration profile of hydrogen in the modifying layer in the thickness direction from a surface of the epitaxial layer is a double peak concentration profile including a first peak shallower in the depth direction and a second peak deeper in the depth direction.

An epitaxial wafer that includes a silicon wafer and an epitaxial layer on the silicon wafer. The silicon wafer contains hydrogen that has a concentration profile including a first peak and a second peak. A hydrogen peak concentration of the first peak and a hydrogen peak concentration of the second peak are each not less than 1?10.sup.17 atoms/cm.sup.3.

The invention relates to a method for forming a porous portion in a substrate, an implantation of ions in at least one region of a layer, for example based on a semiconductor material, so as to form a portion enriched with at least one gas in the implanted region, and then a laser annealing of the nanosecond type so as to form a porous portion. The use of the ion implantation makes it possible to dissociate the deposition of the layer based on semiconductor material from the incorporation of gas. A great variety of porous structures can be obtained by the method. These porous structures can be adapted for numerous applications according to the properties sought.

Protons are injected from a back surface side of a semiconductor substrate to repair both defects within the semiconductor substrate and also defects in a channel forming region on a front surface side of the semiconductor substrate. As a result, variation in gate threshold voltage is reduced and leak current when a reverse voltage is applied is reduced. Provided is a semiconductor device including a semiconductor substrate that includes an n-type impurity region containing protons, on a back surface side thereof; and a barrier metal that has an effect of shielding from protons, on a front surface side of the semiconductor substrate.

A multilayer composite structure and a method of preparing a multilayer composite structure are provided. The multilayer composite structure comprises a semiconductor handle substrate having a minimum bulk region resistivity of at least about 500 ohm-cm and comprises a region of nitrogen-reacted nanovoids in the front surface region; a silicon dioxide layer on the surface of the semiconductor handle substrate; a dielectric layer in contact with the silicon dioxide layer; and a semiconductor device layer in contact with the dielectric layer.