Login (DCU Staff Only)
Login (DCU Staff Only)

DORAS | DCU Research Repository

Explore open access research and scholarly works from DCU

Advanced Search

Surface and interface characterisation of high-k dielectric materials on silicon and III-V semiconductor substrates

Brennan, Barry (2010) Surface and interface characterisation of high-k dielectric materials on silicon and III-V semiconductor substrates. PhD thesis, Dublin City University.

Interface formation between high-k dielectric oxide materials and semiconductor surfaces is of critical importance to the development of the next generation of high speed semiconductor devices. This thesis investigates the deposition and characterisation of a range of candidate high-k materials on both silicon and III-V (InGaAs and InP) semiconductor substrates, with the focus on interface formation.The primary characterisation techniques used to study the interface chemistry were x-ray photoelectron spectroscopy (XPS) and synchrotron radiation based photoemission, while atomic force microscopy (AFM) was used in some experiments for surface roughness measurements. The first part of the study evaluates a range of surface preparation methods prior to dielectric deposition aimed at removing the native oxides and passivating the surfaces while keeping surface roughness to a minimum. Methods investigated for silicon surface preparation included flash cleaning, hydrofluoric acid (HF) etching and the growth of self limiting ultra-thin oxides. For InGaAs the optimisation of the ammonium sulphide (NH4)2S and hydrogen sulphide (H2S) passivation treatments was investigated and an in-depth study of atomic hydrogen cleaning was undertaken. For InP surfaces, an (NH4)2S based treatment was compared to an alternative acid based etch. The dielectric/substrate systems investigated included the reactive deposition of magnesium oxide (MgO) on Si studied by XPS and synchrotron radiation photoemission and aluminium oxide (Al2O3) deposited by atomic layer deposition (ALD) on indium gallium arsenide (InGaAs) also studied by XPS. Electron beam deposition studies of HfO2 were also carried out on InP after various surface treatments, followed by XPS and electrical characterisation to determine the effect of the surface treatments in terms of native oxide and defect generation.
Item Type:Thesis (PhD)
Date of Award:March 2010
Supervisor(s):Hughes, Greg
Subjects:Physical Sciences > Thin films
Physical Sciences > Physics
Physical Sciences > Chemistry
Physical Sciences > Semiconductors
DCU Faculties and Centres:DCU Faculties and Schools > Faculty of Science and Health > School of Physical Sciences
Use License:This item is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 3.0 License. View License
ID Code:15084
Deposited On:31 Mar 2010 10:28 by Gregory Hughes . Last Modified 31 Mar 2010 10:28

Full text available as:

[thumbnail of Barry's_Thesis.pdf]
PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader


Downloads per month over past year

Archive Staff Only: edit this record