Effect of the Interface Mixing Layer on the Thermal Boundary Conductance of Metal-Organic Semiconductor Thin Film–Numerical Study by Lattice Boltzmann Method

The interface mixing of metal-organic semiconductor layers plays a remarkable role in thermal transport in organic electronic devices. Here we apply the lattice Boltzmann method (LBM) to simulate the effect of the interface mixing on thermal boundary conductance (TBC) of Ag-pentacene and Ag-CuPc thin films. The spring constant-dependent transmission coefficient is considered in the simulation to investigate the effect of the interfacial bonding on TBC. The simulation result is compared with the experimental result of Ag-CuPc thin film obtained by other research group. By varying the thickness and composition of the intermixing layer, a significant variation of the thermal boundary conductance of the thin film is observed. The total thermal boundary conductance will increase with the spring constant per area. The increase of the thickness of the intermixing layer leads to the downward trend of the total thermal boundary conductance and it is attributed to the enhancement of the intrinsic thermal resistance of the intermixing layer. These findings suggest the interfacial bonding, thickness and composition of the metal-organic intermixing layer should be carefully controlled to achieve the desired thermal boundary conductance.