Growth of double-barrier β-(AlGa)2O3/Ga2O3 structure and heavily Sn-doped Ga2O3 layers using molecular-beam epitaxy

Abstract

I report on the growth of a double-barrier β-(Al0.15Ga0.85)2O3/Ga2O3/(Al0.15Ga0.85)2O3 heterostructure and heavily Sn-doped β-Ga2O3 layers toward the application of resonant-tunneling diodes. The Ga2O3 and (AlGa)2O3 layers were grown on a β-Ga2O3 (010) substrate by plasma-assisted molecular-beam epitaxy. The heavily Sn-doped β-Ga2O3 layer had a layer resistivity of 2 × 10−3 Ω cm and a specific contact resistivity of 9 × 10−6 Ω cm−2. The diode with the double-barrier (AlGa)2O3/Ga2O3/(AlGa)2O3 structure sandwiched between the heavily Sn-doped Ga2O3 layers exhibited negative differential resistance with a peak-to-valley current ratio of 2 at room temperature.