Analysis of the thermal rectification in silicon structure with triangular holes

Abstract

ABSTRACT Silicon semiconductors with excellent thermoelectric characteristics have been widely used in integrated electronic systems. Thermal rectification has important potential applications in semiconductor devices such as thermal management improvement of electronics and energy saving. The thermal conductivities and thermal rectifications of silicon devices with sets of triangular holes are investigated by nonequilibrium molecular dynamic (NEMD) simulations. The influences of the dimension and angle of the distributed triangular-shaped holes are investigated. The results indicate that the phonon scattering on the side and base of the right-angled triangular holes are quite different, which causes the thermal rectification. The thermal rectification effect is strengthened with the increase of the triangle dimension. However, the variations of the triangular angle have little effect on the thermal conductivities of the silicon device. Besides, the phonon spectral energy density along the frequency axis of the silicon system is given to explain the mechanism behind the rectification phenomenon. Based on the present simulation results, a possible design strategy is proposed for developing highly efficient thermoelectric devices.