采用干涉型光热位移相位信号测量薄膜热扩散率

THERMAL DIFFUSIVITY OF FILMS MEASURED BY INTERFERENTIAL PHOTOTHERMAL DISPLACEMENT PHASE SIGNAL

介绍了待测样品在激光辐照下光热位移信号的理论表达式,阐述了信号相位与热扩散率以及调制频率之间的关系;基于该关系并结合相关资料,提出了一种新的采用迈克尔干涉检测装置测量热扩散率的简便方法,分析了其相对于传统测量方法的优势.采用该装置对Ti及TiO2复合薄膜样品进行了测量,由光热位移相位信号与调制频率之间的关系,计算得到了待测样品的热扩散率.

Theoretical expression of photothermal displacement signal of the sample was introduced under laser irradiation, and the relations between not only the phase of the signal and the thermal diffusivity, but also the phase and the modulated frequency were illustrated. According to these relations, a new simple method using Michael interferential instrument for thermal diffusivity＇s measurement was put forward and its advantages over traditional methods were analyzed. At the same time, this new experiment method was used in thermal diffusivity measurement of Ti/TiO2 film. Based on the relations between the phase and the modulated frequency, the thermal diffusivity of the measured sample was easily obtained with simple calculation.