Thermal Diffusivity of Film/Substrate Structures Characterized by Transient Thermal Grating Method

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2008,（1）
• 页码范围: 176-179
• 页数: 4页
• 语种: 英文

摘要

Transient thermal grating method is used to measure the thermal diffusivity of absorbing films deposited on transparent substrates.According to periodically modulated dielectric constant variations and thermoelastic deformations of the thin films caused by the transient thermal gratings,an improved optical diffraction theory is presented.In the experiment,the probing laser beam reflectively diffracted by the thermal grating is measured by a photomultipliar at different grating fringe spaces.The thermal diffusivity of the film can be evaluated by fitting the theoretical calculations of diffraction signals to the experimental measured data.The validity of the method is tested by measuring the thermal diffusivities of absorbing ZnO films deposited on glass substrates.