Growth of InAs on GaAs(100) by low-pressure metalorganic chemical vapor deposition employing in situ generated arsine radicals

摘要

InAs was grown by low-pressure metalorganic chemical vapor deposition on vicinal GaAs(100) substrates misoriented by 2° toward [001]. We observed InAs crystal growth, at substrate temperatures down to 300℃, employing in situ plasma-generated arsine radicals as the arsenic source. The in situ generated arsine was produced by placing solid arsenic downstream of a microwave driven hydrogen plasma. Trimethylindium (TMIn) feedstock carried by hydrogen gas was used as the indium source. The Arrhenius plot of InAs growth rate vs. reciprocal substrate temperature displayed an activation energy of 46.1 kcal/mol in the temperature range of 300-350℃. This measured activation energy value is very close to the energy necessary to remove the first methyl radical from the TMIn molecule, which has never been reported in prior InAs growth to the best of authors' knowledge. The film growth mechanism is discussed. The crystallinity, infrared spectrum, electrical properties and impurity levels of grown InAs are also presented.