Measurement of interface-state-density distribution near conduction band at interface between atomic-layer-deposited Al2O3 and silicon-doped InAlN

Abstract

The Al2O3/InAlN interface formed by atomic layer deposition on a sufficiently thick silicon-doped InAlN layer lattice matched to GaN was investigated electrically. A metal-oxide-semiconductor (MOS) diode fabricated through careful interface formation showed a minimized leakage current and a capacitance-voltage (C-V) characteristic with a capacitance change large enough to evaluate the interface-state density, in the range of 10(12) eV(-1) cm(-2), near the conduction band. However, the MOS diode with careless interface formation resulted in degraded electrical characteristics, which indicated the process dependence of the interface properties. The effects of the acceptor-like interface states on the C-V curves are discussed. (C) 2013 AIP Publishing LLC

Origin of attendant phenomena of bipolar resistive switching and negative differential resistance in SrTiO3:Nb/ZnO heterojunctions

“…For NSTO/ZnO Schottky junction, the Fermi level in ZnO near interface moves up when @V @t > 0, and it can be higher than the energy level of interface state only by a sufficiently large positive voltage since the acceptor-like interface state always lies in the upper forbidden band. 26,28 When a small voltage is applied to NSTO/ZnO heterojunction, the interface state is not occupied by electrons and will not influence the electrical transport property, so a common Schottky behavior is observed at a small voltage, as shown in Fig. 1(b).…”

“…25 The interface state density is much larger than that in nitride heterojunction interface. 26,27 The high density of acceptor-like interface state is supposed to play an important role in the RS and NDR behaviors when a sufficiently large positive voltage is applied.…”

On the origin of interface states at oxide/III-nitride heterojunction interfaces

“…In particular, for the SiO 2 / Al 0. 26 Table I. This indicates that it is necessary to introduce the positive Q F at the oxide/barrier interface in order to shift V th towards much more negative values.…”

“…1, we present a scheme of the studied MISH structures, i.e. : The investigated heterostructures were passivated using the two-step process: [24][25][26][27][28] (1) covered by a SiN (10 nm) protection film deposited by electron cyclotron resonance chemical vapor deposition (ECR CVD) to avoid damages of semiconductor surfaces during ohmic contact annealing and (2) after removal of the SiN film, covered with an Al 2 O 3 layer (20 nm) deposited by atomic layer deposition (ALD)…”

Interface DOS dependent analytical model development for DC characteristics of normally-off AlN/GaN MOSHEMT

“…3 that oxide/semiconductor interface states have a neutral level approximately at the center of wide band gap barrier layer [13]. All the states above the neutral level are acceptor states and below it are donor states.…”