Integrated semiconductor device and method of manufacturing the same
AssigneeSanken Electric Co., Ltd.
InventorsHironori AOKI, Eiichi Kikkawa
Life of this patent
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Abstract
An integrated semiconductor device and method of manufacturing the same includes leaving one part of a semiconductor layer so that an inclined surface is formed on a trench when forming the trench on a SOI wafer. A thick silicon oxide film (second insulation film) is formed along this incline surface. This thick silicon oxide film prevents oxygen entering a boundary surface between an insulation layer and the semiconductor layer of the SOI wafer within the trench.
Claims12
An integrated semiconductor device comprising;
- a substrate;
- a first insulation film arranged on the substrate;
- a semiconductor layer arranged on the first insulation film and includes a plurality of semiconductor component areas separated by a trench;
- and
- a second insulation film formed in the trench;
- wherein each of the plurality of semiconductor component areas has a fringe part having a smaller thickness than an interval between a main surface of the semiconductor component areas and the first insulation film, and extending below the trench, and the second insulation film is formed on a wall surface of the trench and contacts with the first insulation film.
A method of manufacturing an integrated semiconductor device, the method comprising;
- in a wafer comprised of a substrate, a first insulation film arranged on the substrate, and a semiconductor layer arranged in the first insulation film, forming a trench on the semiconductor layer and extending from the main surface of the semiconductor layer towards the first insulation film in order to separate into a plurality of semiconductor component areas, so that a part which has a smaller thickness than a thickness of the semiconductor layer between a main surface of the semiconductor layer and the first insulation film, remains between the first insulation film;
- and
- forming a second insulation film which covers a wall surface of the trench and contacts with the first insulation film, by oxidizing a part which is exposed on the trench of the semiconductor layer.
A method of manufacturing an integrated semiconductor device, the method comprising;
- in a wafer comprised of a substrate, a first insulation film arranged on the substrate, and a semiconductor layer arranged in the first insulation film, forming a trench on the semiconductor layer from a surface of the semiconductor layer to the first insulation film in order to separate into a plurality of semiconductor component areas;
- forming a part introduced with impurities of a first concentration along a wall surface of a first part from an entrance of the trench of the semiconductor layer to a point in between, and a part introduced with impurities of a second concentration which is higher than the first concentration, along a wall surface of a second part between the first part and an end the trench;
- performing a heat oxidation process of a first temperature on the semiconductor layer in which an oxidation velocity of the second part introduced with impurities of the second concentration is made higher than an oxidation velocity of a first part introduced with impurities of the first concentration, and forming a thicker oxide film than an oxide film on a region introduced with impurities of the first concentration, on the second part introduced with impurities of the second concentration;
- and
- performing a heat oxidation process of a second temperature which is higher than the first temperature, on the semiconductor layer.
Dependencies are inferred from the claim text.