Molecular Beam Epitaxy on Gas Cluster Ion Beam Prepared GaSb Substrates: Towards Improved Surfaces and Interfaces
Abstract
We report results of a surface modification process for (100) GaSb using gas cluster ion beams(GCIB) that removes chemical mechanical polish (CMP) induced surface damage and replaces the native oxide with an engineered surface oxide, the composition of which depends on the reactive gas employed. X-ray photoelectron spectroscopy of O2-, CF4/O2-, and HBr-GCIB surface oxides is presented indicating the presence of mixed Ga- and Sb-oxides, with mostly Ga-oxides at the interface, desorbing at temperatures ranging 530 degrees C to 560 degrees C. Cross-sectional transmission electron microscopy of molecular beam epitaxy grown GaSb/AlGaSb layers showed that the HBr-GCIB surface produced a smooth dislocation-free substrate-to-epi transition with no discernable interface. Topography of epi surfaces, using atomic force microscopy, showed that GCIB surfaces resulted in characteristic step-terrace formations comprising monatomic steps and wide terraces. The HBr-GCIB process can be easily adapted to a large scale manufacturing process to produce epi-ready GaSb substrates.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 14, 2007
- Accession Number
- ADA482541
Entities
People
- Daniel Bakken
- David F. Bliss
- Gordon Dallas
- Helen M. Dauplaise
- Kannan Krishnaswami
- Lisa P. Allen
- Shivashankar Vangala
- William D. Goodhue
Organizations
- Air Force Research Laboratory