title: Ultrathin ZnS and ZnO Interfacial Passivation Layers for Atomic-Layer-Deposited HfO2 Films on InP Substrates.
abstract: Ultrathin ZnS and ZnO films grown by atomic layer deposition (ALD) were employed as interfacial passivation layers (IPLs) for HfO2 films on InP substrates. The interfacial layer growth during the ALD of the HfO2 film was effectively suppressed by the IPLs, resulting in the decrease of electrical thickness, hysteresis, and interface state density. Compared with the ZnO IPL, the ZnS IPL was more effective in reducing the interface state density near the valence band edge. The leakage current density through the film was considerably lowered by the IPLs because the film crystallization was suppressed. Especially for the film with the ZnS IPL, the leakage current density in the low-voltage region was significantly lower than that observed for the film with the ZnO IPL, because the direct tunneling current was suppressed by the higher conduction band offset of ZnS with the InP substrate.
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Energy Engineering, Dankook University , Cheonan 31116, Korea.
authors.forename: So Yeong
authors.initials: SY
authors.lastname: Joo
authors.forename: Hyun Soo
authors.initials: HS
authors.lastname: Jin
authors.affiliation: Department of Energy Engineering, Dankook University , Cheonan 31116, Korea.
authors.forename: Woo-Byoung
authors.initials: WB
authors.lastname: Kim
authors.forename: Tae Joo
authors.initials: TJ
authors.lastname: Park
keywords: HfO2; InP; ZnS; atomic layer deposition; interfacial passivation layer