Analysis of border and interfacial traps in ALD-Y2O3 and -Al2O3 on GaAs via electrical responses - A comparative study
Journal
Microelectronic Engineering
Journal Volume
178
Pages
199-203
Date Issued
2017
Author(s)
Abstract
Y2O3 and Al2O3 were in-situ atomic layer deposited (ALD) on pristine GaAs(001)-4 × 6 reconstructed surfaces without surface pretreatments. We have studied the border and interfacial traps in both hetero-structures using the measured electrical responses. On the basis of frequency dispersion analysis of the capacitance-voltage (CV) characteristics, we conclude that Y2O3 has effectively passivated GaAs surface with a much lower interfacial trap density (Dit) than Al2O3 as the gate dielectric. The quasi-static CV and conductance measurements are in agreement with the above conclusion. We have demonstrated an excellent ALD-Y2O3/GaAs interface with low Dit's of (0.5–2) × 1012 eV−1 cm−2 through the whole GaAs band gap without a mid-gap peak feature.
Type
journal article