| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an inspection apparatus, for a semiconductor integrated- circuit device, which reduces the influence of a noise and which uses laser optical pulses. SOLUTION: A laser is used to inspect a specimen semiconductor integrated- circuit device. A single laser optical pulse from one laser light source is split into two optical pulses, and both of the two optical pulses are made incident on the device to be inspected. The two optical pulses are separated after their interaction with the device to be inspected, and the optical pulses are detected by two photodetectors. Two outputs from the photodetectors are subtracted mutually. By their subtraction, a common-mode which is induced by the two pulses such as a noise caused by the mechanical vibration of the device to be inspected, various noises from the laser light source or the like is erased. Their difference signal is used to extract a time change signal in the device to be inspected.</p> |
