Method and apparatus for measuring thickness of thin films via transient thermoreflectance

摘要

A method for measuring the thickness of a film is based on monitoring a transient change of the reflectivity of the film following an impulsive heating. The method includes the steps of impulsively irradiating a surface of the film with an excitation pulse to cause a rise in temperature in the film; irradiating the surface of the film with a probe beam, such that it reflects off the surface of the film to generate a reflected probe beam; detecting a time-dependent variation in intensity of the reflected probe beam; generating a signal waveform based on the measured variations in intensity; and determining the thickness of the film based on the signal waveform.