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This work reports the quantification of rise in channel temperature due to self-heating in two-terminal SrSnO3 thin film devices under electrical bias. Using pulsed current–voltage (I–V) measurements, thermal resistances of the thin films were determined by extracting the relationship between the channel temperature and the dissipated power. For a 26-nm-thick n-doped SrSnO3 channel with an area of 200 μm2, a thermal resistance of 260.1 ± 24.5 K mm/W was obtained. For a modest dissipated power of 0.5 W/mm, the channel temperature rose to ∼176 °C, a value which increases further at higher power levels. Electro-thermal simulations were performed which showed close agreement between the simulated and experimental I–V characteristics both in the absence and presence of self-heating. The work presented is critical for the development of perovskite-based high-power electronic devices. [ABSTRACT FROM AUTHOR]

We report the results of metal contact resistance, RC, to Nd-doped n-type SrSnO3 films grown by radical-based hybrid molecular beam epitaxy. Sc, Mn, Ti, Al, and Cr contact layers were deposited onto heavily doped SrSnO3 thin films. With no annealing, Al and Cr contacts were found to be highly resistive, while Sc, Mn, and Ti were more conductive, with Mn having the lowest RC of 11 ± 3 Ω-mm, immediately after liftoff. After Al2O3 passivation at 200 °C, Sc, Mn, and Ti contacts all showed Ohmic behavior, with Ti contacts having RC = 2.4 ± 0.3 Ω-mm and a resultant sheet resistance, RS, of 1.66 ± 0.07 kΩ/◻. Specific contact resistivity, ρC, values of 0.03, 0.2, and 0.5 mΩ-cm2 were determined for Ti, Sc, and Mn, respectively. Annealing at 300 °C did not result in any significant change in RC. An additional study was performed using Ti-contacts on bi-layer films consisting of a heavily doped cap layer grown on a moderately doped active layer. It was found that the RC (ρC) of Ti metal to the bi-layer films was ∼1 (2) order(s) of magnitude lower than on single-layer controls. Temperature-dependent analysis was used to extract the barrier height and doping effect for annealed Ti contacts. This work is an important step in evaluating SrSnO3 for use in high-performance and transparent electronic applications. [ABSTRACT FROM AUTHOR]

Beta-phase gallium oxide (β-Ga2O3), the most thermally stable phase of Ga2O3, has stimulated great interest in power electronics due to its ultra-wide bandgap (∼4.9 eV) and high breakdown electric field. The relatively low thermal conductivity of β-Ga2O3, however, limits the device performance due to excessive temperature driven by self-heating. Recently, integrating β-Ga2O3 thin films on substrates with high thermal conductivities has been proposed to improve heat rejection and device reliability. In this work, we prepare high-quality single-crystal β-Ga2O3 thin films by mechanical exfoliation of bulk crystals and study their thermal transport properties. Both the anisotropic thermal conductivity of β-Ga2O3 bulk crystals and the thickness-dependent thermal conductivity of β-Ga2O3 thin films are measured using the time-domain thermoreflectance technique. The reduction in the thin-film thermal conductivity, compared to the bulk value, can be well explained by the size effect resulting from the enhanced phonon-boundary scattering when the film thickness decreases. This work not only provides fundamental insight into the thermal transport mechanisms for high-quality β-Ga2O3 thin films but also facilitates the design and optimization of β-Ga2O3-based electronic devices. [ABSTRACT FROM AUTHOR]