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Emergence of amorphous silicon carbide(a-SiC)thin film based photovoltaic applications has provoked the great interest in its physical properties.In this work,we report the first comprehensive study of thermal transport in the a-SiC thin film from 10 nm to 50 nm at various conditions by using empirical molecular dynamic(MD)simulations.The thermal conductivity increases from 1.38 to 1.75 W/m·K as temperature increases from 100 K to 1100 K.Similar increase of thermal conductivity from 1.4 to 2.09 W/m·K is obtained with density from 2.7 to 3.24 g/cm3.Besides,a slight increase of thermal conductivity(15%)with calculation domain from 10 nm to 50 nm is observed,indicating that size dependence of thermal transport also exists in nanoscale amorphous structures.For physical interpretation of simulation results,the phonon mean free path(MFP)and the specific heat are calculated respectively,which are responsible for the temperature dependence of thermal conductivity.The phonon group velocity is the key factor for the thermal conductivity changing with density.Results also show that the phonon MFP decreases rapidly with temperature,and it is subject to the Matthiessens rule.