Photopyroelectric spectroscopy (PPES) of plasma-enhanced chemical-vapor-deposited a-Si:H thin films on quartz has been performed and compared with the conventional widely used photothermal deflection spectroscopy (PDS). High-modulation-frequency (thermally thick limit) data were combined to yield self-consistent optical-absorption-coefficient and nonradiative quantum efficiency spectra. The quality of the PPES optical-absorption-coefficient spectrum was found to be similar to the PDS spectrum. The former technique, however, has the advantage of not requiring a coupling fluid interface to the delicate, electronically active thin film.

• Received 19 August 1988

DOI:https://doi.org/10.1103/PhysRevB.39.5254