Halogen-induced modification of silicon surfaces: etching roughening, and step transformations

I have combined scanning tunneling microscopy with density functional calculations and Monte Carlo simulations to investigate halogen-induced modifications of Si surfaces, including etching, roughening and step transformations. These investigations have focused on elucidating the atomic-level details associated with the evolution of terrace and step sites on Cl-Si(100)-(2x1) under conditions of halogen supersaturation. I present a novel adsorption mechanism that is accessed upon exposing nearly-saturated Cl-Si(100)-(2x1) to a flux of Cl2, whereby dangling bonds of the nearly-saturated surface mediate the insertion of Cl adsorbates into non-equilibrium adsorption sites. The adsorbates are kinetically trapped within these sites due to energy constraints and lack of available and more favorable adsorption sites. Inserted Cl adsorbates force the surface to evolve along a novel etching pathway at elevated temperature resulting in dimer vacancy formation without the customary Si regrowth features attributed to halogen etching processes. This process is investigated at 700 – 825 K and the reaction mechanism is extracted from analysis of the appropriate rate equations.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Materials Science & Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2010

Author dc:creator

• Butera, Robert E.

Contributors dc:contributor

• Weaver, John H.
• Abelson, John R.
• Petrov, Ivan G.
• Rockett, Angus A.

• Scanning Tunneling Microscopy
• Si(100)
• Halogen etching
• Surface Science
• Steps

Statement dc:rights

• Copyright 2010 Robert E. Butera

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/16827

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/16827