Laser thermometry (LT) techniques, now in their fourth decade of development and application, have been employed in numerous areas of microtechnology for which conventional techniques cannot be employed, such as plasma processing, epitaxial growth, rapid thermal processes, etc. Typical objects of measurement are semiconductor and dielectric crystals, glasses, thin semiconductor and metal films. In the LT, the object under measurement itself serves as a sensor, whose indications are read out with the probing light (usually laser beam). Obviously any temperature-dependent optical property of material can be used in principle for active thermometry. The most important features of LT: a) independence of result on the conditions for heat exchange between the sensor and object under study, and b) full elimination of electrical and optical noise from registered signal. Currently, about 10 techniques are widely used in research and technological monitoring. Despite these achievement and the significant development efforts now underway, some problems remain in bringing LT to routine technological control. In this brief review, present status and problems of the field are discussed.
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