Photocurrent measurements for laterally resolved interface characterization

摘要

A miniaturized optical set-up based on a CD- ROM player optic was developed for LAPS (light ad- jressable potentiometric sensors). A focus of 2.6 j.tm was ilchieved using this easy to handle device. The lateral r~s- Dlution of LAPS measurements can be improved by using GaAs as the semiconductor materiaf instead of Si. The Jiffusion length of the minority charge carriers was deter- mined .to be smaller than 3.1 j.tm. A new method called SPIM (scanning photo-induced impedance microscopy) is jescribed. Using this technique, the impedance of thin r.ilm~ can he measured with lateral resolution.