%development of ac Calorimetric Method for Thermal Diffusivity Measurement of Thin Films.

提出了一种用光辐照交流量热法测量薄样品热扩散率的新方法。讨论了测量的实验条件和基本方程。原则上，无论样品多薄，这种方法都可以应用。这种方法不仅适用于聚合物薄膜等热扩散率较低的材料，也适用于金刚石薄膜等热扩散率较高的材料。在很薄的样品中，应考虑添加剂、热电偶、胶水等对精确测量的贡献。从理论和实验两个方面验证了补充剂不影响热扩散率的测定。我们使用的是部分被掩膜遮盖的矩形板状样品。考虑了测量所需的样本尺寸。对于样品长度，热电偶和交流光照射的样品束之间的距离应该足够长，以使在边界处反射的热波衰减。另一方面，对掩模遮挡的另一个边界没有限制，即热电偶可以放置在边界上。

a new method to measure thermal diffusivity of a thin sample was developed using a light-irradiated ac calorimetric technique. The experimental conditions and the fundamental equations for the measurement are discussed< In principle, this method can be applied no matter how thin a sample may be. This method is applicable to materials not only with low thermal diffusivity such as polymer films but also with ones with high thermal diffusivity such as a diamond film. In a very thin sample, the contribution of addenda, thermocouple, glue etc., to the precise measurement should be considered. From both theory and experiment, it is verified that the addenda do not affect determination of the thermal diffusivity. We used rectangular plate-like samples which were partly shadowed by a mask. The sample dimension required for the measurement was considered. For the sample length, the distance between the thermocouple and the sample bundary on which ac light is irradiated should be sufficiently long so that thermal waves reflected at the boundary decay. On the other hand, there is no restriction on the other boundary shadowed by the mask, i. e., the thermocouple can be placed just at the boundary.