用表面硅微加工工艺研制了一种用于薄膜热容测量的新型微桥量热计,热性能测试与分析表明,微桥量热计温度响应快,温度均匀性较好,采用脉冲量热法,通过测量量热计的热功耗、瞬态温度以及稳态热功耗,可计算量热计和样品薄膜的热容.在真空中300~420K测量了40~1150nm厚的Al薄膜热容,并测量了样品的贡量,获得了样品的比热容,1150nm厚的Al薄膜比热容与Al体材料比热容的文献值吻合较好.随着厚度的减小,Al薄膜的比热容增强,这种现象在高温时更为显著.
A micro bridge calorimeter fabricated with silicon surface micro-fabrication technology is developed for testing heat capacity of thin films. Thermal analyses show that temperature response of the calorimeter is very fast and temperature uniformity is good. With pulse calorimetry, the transient thermal power, transient temperature and steady state heat consumption are measured, and with these data, heat capacity of the calorimeter and sample films can be calculated. Heat capacity of Al thin films with thickness of 40 ~ 1150 nm is measured from 300 K to 420 K in vacuum. The mass of each sample is evaluated and the specific heat capacity is calculated. Results show that specific heat capacity of the 1150 nm Al film agrees well with the literature data of bulk Al. As its thickness decreases, the enhanced specific heat capacity of Al film is observed and this phenomenon becomes more obvious at higher temperature.