Effect of Postdeposition Annealing Temperatures on Electrical Characteristics of Molecular-Beam-Deposited HfO2 on n-InAs/InGaAs Metal-Oxide-Semiconductor Capacitors

Abstract

The electrical characteristics of molecular-beam-deposited HfO2/n-InAs/InGaAs metal-oxide-semiconductor capacitors with different postdeposition annealing (PDA) temperatures (400-550 degrees C) are investigated. Results show that the sample with the PDA temperature of 500 degrees C exhibits the best capacitance-voltage (C-V) behavior with small frequency dispersion and small hysteresis. The X-ray photoelectron spectroscopy (XPS) spectra show the reduction of the amount of As-related oxides to below the XPS detection level when the PDA temperature is up to 500 degrees C. As the PDA temperature was increased to above 500 degrees C, As and In atoms seem to diffuse significantly into HfO2, resulting in the degradation of C-V behavior. (C) 2012 The Japan Society of Applied Physics