Microreflectance difference spectrometer based on a charge coupled device camera: Surface distribution of polishing-related linear defect density in GaAs (001)

We describe a microreflectance difference (μRD) spectrometer based on a charge coupled device (CCD), in contrast to most common RD spectrometers that are based on a photomultiplier or a photodiode as a light detector. The advantage of our instrument over others is the possibility to isolate the RD spectrum of specific areas of the sample; thus topographic maps of the surface can be obtained. In our setup we have a maximum spatial resolution of approximately 2:50 μm×2:50 μm and a spectral range from 1.2 to 5:5 eV. To illustrate the performance of the spectrometer, we have measured strains in mechanically polished GaAs (001) single crystals. © 2009 Optical Society of America.

Charge coupled devices; Defect density; Gallium arsenide; Maps; Semiconducting gallium; Single crystals; Spectrometers; Surface defects; GaAs(001); Spatial resolution; Specific areas; Spectral range; Surface distributions; Topographic map; CCD cameras

VIVO