Abstract

A novel instrument has recently been developed for picosecond time-resolved photoluminescence (TRPL) investigation of GaAs with 3 μm spatial resolution : the Photoluminescence Lifetime Microscope Spectrometer (PLμS). The PLμS is based on time-correlated single photon counting (TCSPC) with a single photon avalanche diode (SPAD) detector. Sensitivity of the PLμS, especially in the near infrared wavelength region (800-1000nm), is several orders of magnitude better than for synchroscan streak cameras. A signal-to-noise ratio of better than 1000:1 is typically obtained from a GaAs sample region of 3 μm diameter at room temperature and at excess carrier densities (at peak excitation) as low as 10¹⁵cm^-3. As a result of the very low optical power requirements, a pulsed diode laser can be used as the excitation source. All signals are conveniently handled via optical fiber, which makes the PLμS a unique instrument for routine assessment of semiconductor materials and devices in an industrial environment.

© 1989 Optical Society of America