Title :
Time-resolved infrared radiometry of laser-heated silicon
Author :
Cho, Kyuman ; Davis, Christopher C.
Author_Institution :
Dept. of Electr. Eng., Maryland Univ., College Park, MD, USA
fDate :
5/1/1989 12:00:00 AM
Abstract :
Time-resolved pulsed photothermal radiometry techniques for the study of the thermal and optical properties of silicon are discussed. By the use of a one-dimensional thermal diffusion equation, a theoretical description for the transient thermal radiation can be developed. Results obtained for relatively heavily doped samples (~0.002 Ω-cm) show that the pulsed photothermal radiometry is an excellent remote diagnostic technique for silicon over a wide range of relatively heavy doping levels. For lightly doped samples (~5 Ω-cm), an anomalously large thermal radiation signal is observed that contradicts the predictions of the thermal diffusion model. The phenomenon can be explained by the enhancement of the gray-body emissivity due to laser-generated free carriers. A simple theoretical model for the free-carrier effect is presented.
Keywords :
elemental semiconductors; high-speed optical techniques; laser beam effects; materials testing; radiometry; silicon; thermal diffusion; time resolved spectra; Si; gray-body emissivity; laser heating; laser-generated free carriers; pulsed photothermal radiometry; thermal diffusion equation; time-resolved infrared radiometry; transient thermal radiation; Absorption; Equations; Geometrical optics; Laser modes; Laser theory; Optical pulses; Radiometry; Semiconductor lasers; Semiconductor process modeling; Silicon;
Journal_Title :
Quantum Electronics, IEEE Journal of