Hitachi-High-Technologies Corporation

Nobuaki Hirose

Hidetoshi Nishiyama

Takahiro Jingu

Hisashi Hatano

Hideki Fukushima

Kazuo Takahashi

This invention implements reduction in the amount of background-scattered light from a semiconductor wafer surface and highly sensitive inspection, without increasing the number of detectors. A surface inspection apparatus that detects defects on the surface of an object (semiconductor wafer surface) to be inspected, by irradiating the surface of the object with a beam of light such as laser light and detecting the light reflected or scattered from the surface; wherein a widely apertured lens with an optical Fourier transform function is disposed between the object to be inspected and a detector, a filter variable in position as well in aperture diameter is provided on a Fourier transform plane, and background-scattered light from the semiconductor wafer surface is effectively blocked, whereby only a signal from a defect such as a foreign substance is detected.

Inspection apparatus

The defect inspecting apparatus is capable of easily performing adjustment with a change of an elevation angle of illumination to a substrate to be inspected, while being low in cost. A plane parallel plate and a cylindrical lens supported by a lens holder are symmetrically disposed at the same tilt angle &#x3b8; with respect to a horizontal plane. A shift in optical axis at a focal position of light () with the rotation of the cylindrical lens can be prevented from occurring. The light can be rotated with a motor and a belt by a rotating mechanism, while allowing the optical axes of the light to match each other at the same focal position. The lens holder and the rotating mechanism are connected to a vertically moving mechanism and moved along a guide of the vertically moving mechanism to thereby adjust the focal position of the cylindrical lens.

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Hitachinaka, Japan

Nobuaki Hirose