Quantum dots photoluminescence based thin film thermal conductivity metrology

Studying thin film thermal conduction is important in the development of many heat related sensors, actuators and microsystems. Emerging non-contact metrologies of membrane thermal conductivity show several advantages when devices are scaling down or novel materials are utilized. In this paper, a method to evaluate membrane thermal conductivity using CdSe/ZnS quantum dots as temperature markers is presented. As an example, the thermal conductivity of 290 nm-thick crystalline silicon thin film is measured as 106 ± 15 W/(m K). Compared to conventional methods, the features of this method, such as fine spatial resolution and non-contact temperature probe, bring the measurement robustness against ambient disturbance and the reduction on measurement system error. Furthermore, this metrology is eligible for thin films of other materials.