The Structure of Si(112):Ga-(N x 1) Reconstructions
Abstract
We have studied the structure of Si(112):Ga-(N*1) reconstructions using atomic-resolution scanning tunneling microscopy and first-principles calculations. The nanofaceted clean Si(112) surface becomes planar following the adsorption of Ga, which forms long chains on the surface interrupted by isolated quasi-periodic defects. The defects create a mixture of (N*1) structures (N~4-7) with 5 1 and 6 1 unit cells most common. We demonstrate that this structure consists of a chain of Ga atoms adsorbed at the (111)-like step edge within the (112) unit cell, and that the defects are Ga vacancies where the exposed step edge Si atoms form a dimer bond. Calculations performed as a function of vacancy period confirm that the surface energy is minimized at N=5-6, when compressive strain associated with the Si-Ga bonds is effectively minimized.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1999
- Accession Number
- ADA482500
Entities
People
- A. A. Baski
- Lloyd J. Whitman
- S. C. Erwin
Organizations
- Virginia Commonwealth University