Unsteady 3-D Nanoscale Heat Transfer across a Thin Film Due to a Moving Heat Source

Micro electronic device technologies and new sub-micron device applications are very common nowadays. Under small time and spatial scales the boundaries and scattering and relaxation time should be regarded. Heat transfer across semiconductors and dielectrics is a result of lattice vibrations. These vibrations make heat waves with sound speed. One quantum of these energy packs called phonon. Boltzmann equation is used to describe these energy transport mechanisms.In recent years heat transfer across thin films studied one-dimensional. Joshi and Majumdar studied the unsteady heat transfer across a thin film. They used the Boltzmann transport equation and derived the EPRT [1]. Raisi and Rostami by using the EPRT studied the unsteady heat transfer in the across of multi-layer alternative thin film of thin film of GaAs and AlAs [2].In this work Three-dimensional equation of phonon radiative transfer is derived and numerically solved. The problem is solved with moving source heating both with EPRT and the Fourier Law. The grid study is done and the stability is checked. Furthermore the results of nano scales and larger scales are compared