Advanced RHEED Instrumentation for the Analysis of the Initial Stages of MBE Quantum Dot Growth for Semiconductor Lasers
Abstract
The Staib Instruments EK-15-R RHEED System purchased on this DURIP grant has been mounted in the University of New Mexico's (UNM) Vacuum Generators VH80 MBE system and used extensively for RHEED studies during the growth of antimony-bearing semiconductors. The beam rocking feature in this unit has been critical in establishing the exact angle of incidence needed for clear observation of reconstruction patterns during the growth of bulk and digital alloy materials, and for the observation of RHEED oscillations to determine the precise growth rate. Observation of RHEED reconstruction patterns is particularly crucial in the growth of Digital Alloy (DA) materials. Arsenic-free GaInSb quantum well lasers for 2-5 nanometer applications were fabricated by growing a graded digital alloy AlInSb metamorphic buffer layer on GaSb to tailor the lattice constant The relaxation of the AlInSb DA buffer layer generates dislocations that are turned along the slip plane at strained heterojunctions. By increasing the number of heterojunctions, filtering of dislocations is possible. Below 200K the laser threshold was virtually constant, and a characteristic temperature T0 of 107K was found above 200K. This is the highest reported T0 for a semiconductor laser at this wavelength.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 10, 2001
- Accession Number
- ADA395259
Entities
People
- Luke F. Lester
Organizations
- University of New Mexico