Electrical characterization of thin Al2O3 films grown by atomic layer deposition on silicon and various metal substrates

Abstract Al2O3 films with thicknesses ranging from 30 to 3540 A were grown in a viscous flow reactor using atomic layer deposition (ALD) with trimethylaluminum and water as the reactants. Growth temperatures ranged from 125 to 425 °C. The Al2O3 ALD films were deposited successfully on a variety of substrates including Au, Co, Cr, Cu, Mo, Ni, NiFe, NiMn, Pt, PtMn, Si, stainless steel, W, and ZnO. Electrical properties were characterized by current–voltage and capacitance–voltage measurements using a mercury probe. These measurements focused mainly on Al2O3 ALD films deposited on n-type Si(1 0 0) and on Mo-coated Si(1 0 0) substrates. Excellent insulating properties were observed for nearly all of the Al2O3 films. For a typical Al2O3 ALD film with a 120 A thickness, leakage currents of