Asahi Kogaku Kogyo Kabushiki Kaisha

Sumitomo Mitsubishi Silicon Corporation

Hirotaka Fujii

Suguru Takishima

Satoshi Murakami

Shigeru Umeno

Wataru Kubo

It is an object of the present invention to provide an epitaxial wafer with fewer pit defects in the epitaxial layer of a silicon monocrystalline wafer that has been doped with arsenic. Pit defects tend to occur when gas etching is performed prior to epitaxial film formation, but this tendency is reversed and a sound epitaxial layer is obtained by setting the crystal plane orientation to (100) and specifying the range of the tilt angle for the angle &#x3b8; in the [001] direction or [00] direction or the angle &#x3c6; in the [00] direction or [010] direction with respect to the [100] axis.

Epitaxial wafer and method for manufacturing method

A detecting system for detecting a rotation angle of a deflecting mirror is disclosed. The detecting system is provided with a laser diode, an objective lens, and a deflection mirror therebetween. The deflection mirror is rotatable about a predetermined rotation axis to change the position, on an optical disc, at which a laser beam emitted by the laser diode is incident. Further, a beam splitter is provided to split the light beam into a first beam directed to the optical disc via the deflection mirror, and a second beam that is directed to a reflection surface of the deflection mirror. The second beam reflected by the reflection member is not directed to the optical disc but received by a detector which determines the rotation angle of the deflection mirror in accordance with the received second beam.

Detecting system for detecting rotation angle of deflection mirror

Disclosed is a rotation amount detecting system for detecting a rotation amount of a deflection mirror, which is rotatable about an rotation axis, employed in an optical disc drive. The rotation amount detecting system is provided with a light emitting system that emits a light beam to the deflection mirror. The light beam has a line-like cross section extending in a direction perpendicular to the rotation axis. Further, a detecting system is provided to receive the beam reflected by the deflection mirror and determines the rotation amount of the deflection mirror in accordance with the received beam.

Growing community of inventors

Tokyo, Japan

Hirotaka Fujii