This paper presents the advantages and disadvantages of using triethylgallium (TEGa) and trimethylgallium (TMGa) for realization of high-purity, carbon-free, epitaxial Ga2O3 films. Critical process conditions and MOCVD reactor geometries on achieving high purity β-Ga2O3 films with high electron mobility and low background carrier concentration, including doping control in this range, will be discussed. This paper will also discuss the MOCVD growth of high Al composition (up to 30%) high quality strained β-(AlGa)2O3/Ga2O3 heterostructures. To obtain semi insulating films, we will discuss Ga2O3 doping with nitrogen, comparing various nitrogen precursors. We will present the limitations of MOCVD technique for achieving heavily doped (>1020 1/cm3), highly conductive β-Ga2O3. We will present a new in-situ etching process for Ga2O3 in MOCVD using Ga and Cl based chemistry.
|