Deposition of HfO2 on InAs by atomic-layer deposition

Summary, in English

Metal-oxide-semiconductor (MOS) capacitors are formed on bulk InAs substrates by atomic-layer deposition (ALD) of HfO2. Prior to film growth, InAs substrates receive a wet-chemical treatment of HCl, buffered HF (BHF), or (NH4)(2)S. Hafnium dioxide films are grown using 75 ALD cycles with substrate temperatures of 100, 200, and 300 degrees C. Substrate temperature is found to have a significant influence on the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of the capacitors, while the influence of substrate pretreatment manifests itself in interface trap density, D-it, as measured by the Terman method. (C) 2009 Elsevier B.V. All rights reserved.