Incorporation of GTR (generation-transport-recombination) in semiconductor simulations

摘要

With the emergence of phase change memory, where the devices experience extreme thermal gradients (～100K/nm) during transitions between low and high resistive states, the study of thermoelectric effects at small scales becomes particularly relevant. We had earlier observed asymmetric melting of self-heated nano-crystalline silicon micro-wires, where current densities of ～10~7 A/cm~2 were forced through the wires by 1 μs, ～30 V pulses. The extreme asymmetry can be explained by the generation of considerable amount of minority carriers, transport under the electric field, and recombination downstream, a heat transfer process we termed as generation-transport-recombination, which is in opposite direction of the electronic-convective heat carried by the majority carriers. Here, we present a full semiconductor physics treatment of this carrier-lattice heat transport mechanism and the contribution of the minority carriers on the evolution of the melt-solid interface, which can be applied to various high-temperature electronic devices.