Thermal boundary resistance enhancement through interfacial polarization electric field induced in GaN/InxGa1-xN superlattice

Abstract

In this paper, we have theoretically investigated the effect of interfacial polarization electric (IPE) field due to interfaces on thermal boundary resistance (TBR) of GaN/InGaN superlattices (SLs). The distribution of temperature in the active region of GaN/InGaN devices determines the TBR including and excluding IPE field induced by the strain of the SL compared with experiments and thermal simulations. The calculated TBR was found to be 9.3 × 10 −9 W −1 m 2 K for devices at room temperature which plays a key role in thermal management of the devices. The determined effective TBR was found to decrease with temperature; but was enhanced by polarization mechanism developed at the interface of GaN/InGaN SL. The contribution of very low thermal conductivity of InGaN layer of the SLs for improved thermoelectric efficiency requires comparatively a large value of TBR and its temperature dependences are also discussed. • Interfacial electric field is exploited to enhance thermal boundary resistance of GaN/In x Ga 1-x N/GaN SLs. • Electric field modifies thermal parameters and phonon properties of SL via inverse piezoelectric effect. • TBR is enhanced from 2.10 to 5. 30 × 10 −9 m 2 KW −1 closer to reported value of InGaAs SL. • TBR is enhanced in presence of field and shows more than 15% ehancement due to enhanced TBR. • k cp in presence (absence) of field for x = 0.1 and 0.9 are 4.652 (5.710) and 6.083 (7.327) Wm −1 K −1 .