Noncontact temperature measurements of diamond by Raman scattering spectroscopy

Abstract
The possibility of determining the temperature of diamond by noncontact Raman spectroscopy is assessed critically. The intensity ratio of Stokes to anti-Stokes lines is shown to be ill suited for temperatures above ∼750 K. Employing the temperature coefficient of the Raman line position, on the other hand, turns out to be a straightforward and highly reliable means to measure diamond temperatures between 300 and 2000 K with an accuracy of ±10 K. A prerequisite for the application of this method is an empirically developed formula which describes the temperature coefficient of the Raman active phonon frequency with high accuracy. Examples of temperature measurements on single crystal diamond and diamond films grown by chemical vapor deposition are given. The application of this procedure to the temperature measurement of silicon and germanium is demonstrated.