Study of the Preparation of III-V Alloy Semiconductors with Controlled Band Gaps.
AUTONETICS ANAHEIM CALIF
Pagination or Media Count:
The feasibility of using a metalorganic-hydride process for the formation of epitaxial layers of Ga1-xInxAs alloy semiconductors on n-type GaAs and InAs single-crystal substrates has been investigated. Conditions have been established for the preparation of single-crystal layers with bandgap energies between 0.7 and 0.8 eV. The investigation has been based on a chemical vapor deposition process employing metalorganics such as trimethylgallium and triethylindium and gaseous hydrides such as arsine for growth of the alloys on the above substrates and on sapphire Al2O3, the latter to facilitate evaluation of the alloy films. The feasibility of growth of alloys in a range of compositions has been clearly demonstrated. Carrier concentrations the order of 10 to the 16th power cu cm or below have been obtained, and room temperature mobilities as high as nearly 10,000 sq cmV-sec on 0001 Al2O3 and over 4000 sq cmv-sec on 111 GaAs A face have been achieved. Experimentally determined optical bandgap energies and alloy compositions for the Ga1-xInxAs films indicate a smooth continuous variation of bandgap with the mole fraction of either cation. A bandgap energy of 0.7 eV results for a film containing 0.40 - 0.45 mole fraction of Ga. Author
- Solid State Physics