Suppression of particle formation by gas-phase pre-reactions in (100) MOVPE-grown <b> <i>β</i> </b>-Ga2O3 films for vertical device application
Ta‐Shun Chou, Palvan Seyidov, Saud Bin Anooz, Raimund Grüneberg, Mike Pietsch, Jana Rehm, Thi Thuy Vi Tran, Kornelius Tetzner, Zbigniew Galazka, M. Albrecht, K. Irmscher, Andreas Fiedler, Andreas Popp
Abstract
This work investigated the metalorganic vapor-phase epitaxy (MOVPE) of (100) β-Ga2O3 films with the aim of meeting the requirements to act as drift layers for high-power electronic devices. A height-adjustable showerhead achieving a close distance to the susceptor (1.5 cm) was demonstrated to be a critical factor in increasing the stability of the Ga wetting layer (or Ga adlayer) on the surface and reducing parasitic particles. A film thickness of up to 3 μm has been achieved while keeping the root mean square below 0.7 nm. Record carrier mobilities of 155 cm2 V−1 s−1 (2.2 μm) and 163 cm2 V−1 s−1 (3 μm) at room temperature were measured for (100) β-Ga2O3 films with carrier concentrations of 5.7 × 1016 and 7.1 × 1016 cm−3, respectively. Analysis of temperature-dependent Hall mobility and carrier concentration data revealed a low background compensating acceptor concentration of 4 × 1015 cm−3.