Spatially and time-resolved infrared absorption for optical and electrical characterization of indirect band gap semiconductors

• Published in: Thin solid films Vol. 364; no. 1-2; pp. 181 - 185
• Main Authors: GRIVICKAS, V, GALECKAS, A, BIKBAJEVAS, V, LINNROS, J, TELLEFSEN, J. A
• Format: Conference Proceeding Journal Article
• Language: English
• Published: Lausanne Elsevier Science 27.03.2000
• Subjects: absorption; Charge carriers: generation, recombination, lifetime, and trapping; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conductivity phenomena in semiconductors and insulators; electronic properties; Electronic transport in condensed matter; Elemental semiconductors and insulators; Exact sciences and technology; free-carrier absorption; Infrared and raman spectra and scattering; lifetime; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; optical spectroscopy; Physics; silicon; silicon carbide; transients; Semiconductor materials; Silicon carbides; Electron hole pair; Infrared spectra; Experimental study; Free carrier; Time resolution; Energy gap; Charge carrier recombination; Silicon; Absorption spectra; Carrier density; Depth profiles; Auger recombination; Spatial resolution; Charge carrier injection
• ISSN: 0040-6090; 1879-2731; 1879-2731
• DOI: 10.1016/S0040-6090(99)00895-0

The current status of the spatially and time-resolved free-carrier absorption (FCA) method is provided. The FCA technique allows monitoring carrier dynamics in a time scale from nanoseconds to miliseconds by employing either collinear or orthogonal geometry between pump and probe beams. A high spatial resolution is achieved allowing in-depth carrier profiles to be extracted. The method is particularly suited for investigation of injection-dependent optical and recombination phenomena: band gap optical absorption, Shockley-Read-Hall (SRH) lifetime, Auger recombination coefficient, and the injection-dependent surface (interface) recombination velocity. We summarize important aspects of the technique demonstrating numerous measurements that have been implemented in studies of bulk Si, epilaxial 4H-SiC and porous silicon.