BROWSE
Detail
Journal Article
Rare-Earth Gate Oxides for GaAs MOSFET Application
Cited 4 time in 
Share 
Share
- Authors
- Kwang Ho Kwon, Jun Kyu Yang, Hyung Ho Park, Jong Dae Kim, Tae Moon Roh
- Issue Date
- 2006-08
- Citation
- Applied Surface Science, v.252, no.21, pp.7624-7630
- ISSN
- 0169-4332
- Publisher
- Elsevier Science, Elsevier
- Language
- English
- Type
- Journal Article
- Abstract
- Rare-earth oxide films for gate dielectric on n-GaAs have been investigated. The oxide films were e-beam evaporated on S-passivated GaAs, considering interfacial chemical bonding state and energy band structure. Rare-earth oxides such as Gd 2 O 3 , (Gd x La 1-x ) 2 O 3 , and Gd-silicate were employed due to high resistivity and no chemical reaction with GaAs. Structural and bonding properties were characterized by X-ray photoemission, absorption, and diffraction. The electrical characteristics of metal-oxide-semiconductor (MOS) diodes were correlated with material properties and energy band structures to guarantee the feasibility for MOS field effect transistor (FET) application. Gd 2 O 3 films were grown epitaxially on S-passivated GaAs (0 0 1) at 400 °C. The passivation induced a lowering of crystallization temperature with an epitaxial relationship of Gd 2 O 3 (4 4 0) and GaAs (0 0 1). A better lattice matching relation between Gd 2 O 3 and GaAs substrate was accomplished by the substitution of Gd with La, which has larger ionic radius. The in-plane relationship of (Gd x La 1-x ) 2 O 3 (4 4 0) with GaAs (0 0 1) was found and the epitaxial films showed an improved crystalline quality. Amorphous Gd-silicate film was synthesized by the incorporation of SiO 2 into Gd 2 O 3 . These amorphous Gd-silicate films excluded defect traps or current flow path due to grain boundaries and showed a relatively larger energy band gap dependent on the contents of SiO 2 . Energy band parameters such as ?봂 C , ?봂 V , and E g were effectively controlled by the film composition. © 2006 Elsevier B.V. All rights reserved.