Abstract: An electrostatic actuator for increasing a swing (deflection angle) of a movable structure includes a laminate substrate in which a thin film silicon layer is formed on a silicon substrate through a buried insulating film and a torsion beam movable structure constructed with the thin film silicon layer. A potential difference is generated between a movable side comb-tooth electrode of the movable structure and a fixed side comb-tooth electrode disposed to face the movable side comb-tooth electrode to swing the movable structure. The fixed side comb-tooth electrode is formed in the inside of a through hole bored through the laminate substrate.

Abstract: An electrostatic actuator for increasing a swing (deflection angle) of a movable structure includes a laminate substrate in which a thin film silicon layer is formed on a silicon substrate through a buried insulating film and a torsion beam movable structure constructed with the thin film silicon layer. A potential difference is generated between a movable side comb-tooth electrode of the movable structure and a fixed side comb-tooth electrode disposed to face the movable side comb-tooth electrode to swing the movable structure. The fixed side comb-tooth electrode is formed in the inside of a through hole bored through the laminate substrate.

Abstract: An electrostatic actuator for increasing a swing (deflection angle) of a movable structure includes a laminate substrate in which a thin film silicon layer is formed on a silicon substrate through a buried insulating film and a torsion beam movable structure constructed with the thin film silicon layer. A potential difference is generated between a movable side comb-tooth electrode of the movable structure and a fixed side comb-tooth electrode disposed to face the movable side comb-tooth electrode to swing the movable structure. The fixed side comb-tooth electrode is formed in the inside of a through hole bored through the laminate substrate.

Abstract: Before a semiconductor substrate and a base substrate is directly bonded to one another, in a protective film removing step, a contamination protective film formed on the semiconductor substrate to protect it from contamination during an ion implanting step is removed. Consequently, even when flatness of the contamination protective film is degraded during the ion implanting step or even when contaminants remain in a segregated state in the vicinity of the surface of the contamination protective film, the state of the bonding between the semiconductor substrate and the base substrate after the bonding step can be made uniform over the entire area of the bonding. As a result, a high-quality semiconductor substrate can be manufactured at low cost.

Abstract: A trench is formed in a silicon substrate, and an epitaxial film is formed on the substrate and in the trench. After a part of the epitaxial film formed around an opening portion of the trench is etched, another epitaxial film is formed on the substrate and in the trench. Accordingly, the trench can be filled with the epitaxial films completely. Then, the surface of the substrate is flattened.

Abstract: The invention provides a number of semiconductor substrate manufacturing methods with which, in manufacturing a semiconductor substrate having a semiconductor layer in an insulated state on a supporting substrate, it is possible to obtain a thick semiconductor layer with a simple process and cheaply while reducing impurity contamination of the semiconductor layer to a minimum.

Abstract: Methods for manufacturing semiconductor substrates in which a semiconductor layer for forming semiconductor device therein is formed on a supporting substrate with an insulating film interposed between, with which in forming the semiconductor layer on a substrate on which a buried pattern structure has been formed it is possible to greatly increase the film thickness uniformity of the semiconductor layer and the film thickness controllability, particularly when the semiconductor layer is being formed as an extremely thin film. As a result, it is possible to achieve improved quality and characteristics of the semiconductor substrates and make possible the deployment of such semiconductor substrates to various uses.

Abstract: An island region surrounded by a trench is provided in an SOI substrate. The island region is further surrounded by a buffer region with a buffer region contact layer. In the island region, a source region is annularly provided around a drain region, and source and drain electrodes are respectively provided on the source and the drain regions. An annular auxiliary electrode is formed with the source electrode to extend over the trench. Accordingly, a voltage applied to the source electrode can be applied to the auxiliary electrode, so that electric field concentration between the buffer region and the source electrode is relaxed.