Physical and electrical characterizations of metal-oxide-semiconductor capacitors fabricated on GaAs substrates with different surface chemical treatments and Al2O3 gate dielectric
- 1 November 2009
- journal article
- Published by American Vacuum Society in Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures
- Vol. 27 (6), 2390-2395
- https://doi.org/10.1116/1.3256229
Abstract
The authors present experimental evidence on the impact of three different chemical surface treatments on the interface between the GaAs substrate and the aluminum oxide dielectric layer used in the fabrication of metal-oxide-semiconductor capacitors. The three different chemical surface treatments studied prior to atomic layer deposition (ALD) of the dielectric layer include (a) GaAs native oxide removal in a dilute HF solution only, (b) HF etch followed by a treatment, and (c) HF etch followed by a treatment. Moreover, interfacial self-cleaning of nontreated GaAs wafers upon ALD of aluminum oxide using trimethyl aluminum precursor was examined. Transmission electron microscopy, electron energy loss spectroscopy (EELS) and capacitance-voltage data showed slight differences among the nontreated, HF-only, and treated samples. However the treated sample showed improved capacitance-voltage characteristics as well as an improved aluminum oxide/GaAs interface compared to the other three samples. Additionally, the characteristic oxygen EELS peak suggests the presence of a thin additional layer close to the center of the high- layer containing oxygen, tantalum, and aluminum, as a consequence of probable plasma damage to the high- layer during the TaN metal gate deposition.
Keywords
This publication has 21 references indexed in Scilit:
- Self-aligned inversion-type enhancement-mode GaAs metal-oxide-semiconductor field-effect transistor with Al2O3 gate dielectricApplied Physics Letters, 2008
- Self-aligned n-channel metal-oxide-semiconductor field effect transistor on high-indium-content In0.53Ga0.47As and InP using physical vapor deposition HfO2 and silicon interface passivation layerApplied Physics Letters, 2008
- Influence of the substrate orientation on the electrical and material properties of GaAs metal-oxide-semiconductor capacitors and self-aligned transistors using HfO2 and silicon interface passivation layerApplied Physics Letters, 2008
- Carbon segregation as a strain relaxation mechanism in thin germanium-carbon layers deposited directly on siliconJournal of Applied Physics, 2006
- Pure germanium epitaxial growth on thin strained silicon-germanium graded layers on bulk silicon substrate for high-mobility channel metal-oxide-semiconductor field-effect transistorsJournal of Electronic Materials, 2006
- Thin germanium-carbon alloy layers grown directly on silicon for metal-oxide-semiconductor device applicationsApplied Physics Letters, 2006
- High mobility NMOSFET structure with high-/spl kappa/ dielectricIEEE Electron Device Letters, 2005
- Hf O 2 and Al2O3 gate dielectrics on GaAs grown by atomic layer depositionApplied Physics Letters, 2005
- Vertical p-type high-mobility heterojunction metal–oxide–semiconductor field-effect transistorsApplied Physics Letters, 2001
- Interfacial properties of metal–insulator–semiconductor capacitors on GaAs(110)Journal of Vacuum Science & Technology A, 1995