Microwave heating of thin Cu film

Thin Cu films with different thickness and microstructure were prepared using evaporation with a quartz substrate, followed by microwave irradiation in air (frequency of microwave:2.45 GHz, incident flux of microwave:563 W, in-adiation time: 600 s). Microwave heating of thin Cu film is quite anomalous. The abrupt temperature rise and drop occur at early stage of microwave irradiation, then continuous temperature rise appears. The temperature change is caused by various combinations of the change in the rate of temperature rise (Delta T) due to the ratio of a thickness to resistivity of thin Cu film, the increases in AT due to Cat-oxide and resistivity rise at elevated temperature, and the decreases in AT due to Cu particle growth during microwave irradiation and heat radiation from the surface of thin Cu film.