Abstract: A process for producing a semiconductor substrate comprising a carrier wafer and a layer of single-crystalline semiconductor material: a) producing a layer containing recesses at the surface of a donor wafer of single-crystalline semiconductor material, b) joining the surface of the donor wafer containing recesses to the carrier wafer, c) heat treating to close the recesses at the interface between the carrier wafer and the donor wafer to form a layer of cavities within the donor wafer, and d) splitting the donor wafer along the layer of cavities, resulting in a layer of semiconductor material on the carrier wafer. Semiconductor substrates prepared thusly may have a single-crystalline semiconductor layer having a thickness of 100 nm or less, a layer thickness uniformity of 5% or less, and an HF defect density of 0.02/cm2 or less.

Abstract: A process for producing a semiconductor substrate comprising a carrier wafer and a layer of single-crystalline semiconductor material: a) producing a layer containing recesses at the surface of a donor wafer of single-crystalline semiconductor material, b) joining the surface of the donor wafer containing recesses to the carrier wafer, c) heat treating to close the recesses at the interface between the carrier wafer and the donor wafer to form a layer of cavities within the donor wafer, and d) splitting the donor wafer along the layer of cavities, resulting in a layer of semiconductor material on the carrier wafer. Semiconductor substrates prepared thusly may have a single-crystalline semiconductor layer having a thickness of 100 nm or less, a layer thickness uniformity of 5% or less, and an HF defect density of 0.02/cm2 or less.

Abstract: A process for producing a semiconductor substrate comprising a carrier wafer and a layer of single-crystalline semiconductor material: a) producing a layer containing recesses at the surface of a donor wafer of single-crystalline semiconductor material, b) joining the surface of the donor wafer containing recesses to the carrier wafer, c) heat treating to close the recesses at the interface between the carrier wafer and the donor wafer to form a layer of cavities within the donor wafer, and d) splitting the donor wafer along the layer of cavities, resulting in a layer of semiconductor material on the carrier wafer. Semiconductor substrates prepared thusly may have a single-crystalline semiconductor layer having a thickness of 100 nm or less, a layer thickness uniformity of 5% or less, and an HF defect density of 0.02/cm2 or less.

Abstract: A silicon single crystal which has been produced using the Czochralski method has a <113> orientation.

Abstract: A semiconductor substrate useful as a donor wafer is a single-crystal silicon wafer having a relaxed, single-crystal layer containing silicon and germanium on its surface, the germanium content at the surface of the layer being in the range from 10% by weight to 100% by weight, and a layer of periodically arranged cavities below the surface. The invention also relates to a process for producing this semiconductor substrate and to an sSOI wafer produced from this semiconductor substrate.

Abstract: A semiconductor substrate useful as a donor wafer is a single-crystal silicon wafer having a relaxed, single-crystal layer containing silicon and germanium on its surface, the germanium content at the surface of the layer being in the range from 10% by weight to 100% by weight, and a layer of periodically arranged cavities below the surface. The invention also relates to a process for producing this semiconductor substrate and to an sSOI wafer produced from this semiconductor substrate.

Abstract: An SOI wafer, includes a substrate made from silicon, an electrically insulating layer with a thermal conductivity of at least 1.6 W/(Km) and a single-crystal silicon layer with a thickness of from 10 nm to 10 ?m, a standard deviation of at most 5% from the mean layer thickness and a density of at most 0.5 HF defects/cm2. A process is for producing an SOI wafer of this type, in which a substrate wafer made from silicon is joined to a donor wafer via a layer of the electrically insulating material which has previously been applied. The donor wafer bears a donor layer of single-crystal silicon, with a concentration of vacancies of at most 1012/cm3 and of vacancy agglomerates of at most 105/cm3. After the wafers have been joined, the thickness of the donor wafer is reduced in such a manner that the single-crystal silicon layer having these properties is formed from the donor layer, this single-crystal silicon layer being joined to the substrate wafer via the layer of electrically insulating material.

Abstract: A semiconductor wafer has a monocrystalline silicon layer and a graded silicon-germanium layer adjacent thereto, of thickness d and composition Si1-xGex, where x represents the proportion of germanium and 0<x?1, and where x assumes greater values with increasing distance a from the monocrystalline silicon layer, wherein the relationship between the proportion x(d) of germanium at the surface of the graded silicon-germanium layer and the proportion x(d/2) of germanium at the center distance between the monocrystalline silicon layer and the surface of the graded silicon-germanium layer is x(d/2)>0.5·x(d). The wafer may be further processed, in which process a layer of the semiconductor wafer is transferred to a substrate wafer.

Abstract: The invention relates to a semiconductor wafer, which, at its surface comprises a semiconductor surface layer with a thickness in the range from 3 nm to 200 nm having no hole defects, and which comprises an adjoining electrically insulating layer beneath the semiconductor surface layer.

Abstract: A semiconductor substrate useful as a donor wafer is a single-crystal silicon wafer having a relaxed, single-crystal layer containing silicon and germanium on its surface, the germanium content at the surface of the layer being in the range from 10% by weight to 100% by weight, and a layer of periodically arranged cavities below the surface. The invention also relates to a process for producing this semiconductor substrate and to an sSOI wafer produced from this semiconductor substrate.

Abstract: A process for producing a semiconductor substrate comprising a carrier wafer and a layer of single-crystalline semiconductor material: a) producing a layer containing recesses at the surface of a donor wafer of single-crystalline semiconductor material, b) joining the surface of the donor wafer containing recesses to the carrier wafer, c) heat treating to close the recesses at the interface between the carrier wafer and the donor wafer to form a layer of cavities within the donor wafer, and d) splitting the donor wafer along the layer of cavities, resulting in a layer of semiconductor material on the carrier wafer. Semiconductor substrates prepared thusly may have a single-crystalline semiconductor layer having a thickness of 100 nm or less, a layer thickness uniformity of 5% or less, and an HF defect density of 0.02/cm2 or less.

Abstract: An SOI wafer, includes a substrate made from silicon, an electrically insulating layer with a thermal conductivity of at least 1.6 W/(Km) and a single-crystal silicon layer with a thickness of from 10 nm to 10 &mgr;m, a standard deviation of at most 5% from the mean layer thickness and a density of at most 0.5 HF defects/cm2.

Abstract: A method for producing a pleated filter material from a nonwoven fabric having spacers for the pleated folds formed from the filter material itself, a formed fabric made of stretched synthetic fibers and thermoplastic and/or thermally cross-linked binding agent being heated in an oven to a temperature lying at least in the softening temperature range and/or the cross-linking temperature range of the binding agent, and subsequently, the formed fabric being formed between profiled calender rolls and cooled simultaneously.

Abstract: A silicon single crystal which has been produced using the Czochralski method has a <113 > orientation.

Abstract: A filter made of nonwoven fabric, paper or the like for gaseous media, having an electrically conductive coating made of a conductive substance of pulverizable materials, in particular from electrically conductive carbon-black particles and/or powdery metal particles or other pulverized materials, the carbon-black particles or metal particles being fixed to the filter fibers with the aid of binding agents, and the conductive coating being applied in a reticulated manner on the filtering layer.

Abstract: A method for producing a pleated filter material from a nonwoven fabric having spacers for the pleated folds formed from the filter material itself, a formed fabric made of stretched synthetic fibers and thermoplastic and/or thermally cross-linked binding agent being heated in an oven to a temperature lying at least in the softening temperature range and/or the cross-linking temperature range of the binding agent, and subsequently, the formed fabric being formed between profiled calender rolls and cooled simultaneously.