Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
544658 | Microelectronic Engineering | 2011 | 4 Pages |
Interfacial chemical analyses and electrical characterization of in situ atomic layer deposited (ALD) Al2O3 on freshly molecular beam epitaxy (MBE) grown n- and p- GaAs (001) with a (4 × 6) surface reconstruction are performed. The capacitance–voltage (C–V) characteristics of as-deposited and 550 °C N2 annealed samples are correlated with their corresponding X-ray photoelectron spectroscopy (XPS) interfacial analyses. The chemical bonding for the as-deposited ALD-Al2O3/n- and p-GaAs interface is similar, consisting of Ga2O (Ga1+) and As-As bonding (As0) without any detectable arsenic oxides or Ga2O3; the interfacial chemical environments remained unchanged after 550 °C N2 annealing for 1hr. Both as-deposited and annealed p-GaAs metal–oxide-semiconductor capacitors (MOSCAPs) exhibit C–V characteristics with small frequency dispersion (<5%). In comparison, n-GaAs MOSCAPs shows much pronounced frequency dispersion than their p-counterparts.