Vapor deposition of high-purity GaAs epilayers using monoethylarsine

Abstract

High-purity GaAs epitaxial layers have been successfully grown using the novel organoarsine reagent source, monoethylarsine (EtAsH2), with trimethylgallium (Me3Ga) as the gallium reagent. Films were found to be n type for all growth parameters examined (V/III=5–30, growth temperature=550–650 °C). Film quality improved as V/III ratio increased, whereas the optimum growth temperature ranged between 575 and 600 °C. The highest purity film produced using EtAsH2 and Me3Ga was grown using a V/III ratio of 30 and a growth temperature of 575 °C. This epilayer exhibited mobilities of 55 300 cm2/V s and 7200 cm2/V s at 77 and 300 K, respectively (as determined by van der Pauw–Hall measurements), and had a net carrier concentration of 6×1014 cm−3. These results closely rival those of the best arsine alternatives studied to date, and indicate that EtAsH2 is an extremely promising reagent to replace arsine for use in vapor deposition applications.

Effect of Pt / Al2 O 3 Catalyst on GaAs Grown by Low Pressure TEAs‐TMGa Organometallic Vapor‐Phase Epitaxy

“…GaAs + 3H --> Ga + AsH3 [3] Therefore, by comparing the thermal etching rate with and without Pt/A12Q catalyst, we can investigate the propagation properties of the reactive hydrogen atoms generated by the Pf/AI~O5 catalyst. Platinum (Pt) on ~/-A1205 ceramics of a hemispheric shape (3 mm in diam) was used as the catalyst.…”

Hydrogen Cracking by a Pt / Al2 O 3 Catalyst and Its Propagation to GaAs Substrates for TMGa‐TEAs Organometallic Vapor‐Phase Epitaxy

“…However, undesirable carbon incorporation occurs since the alkylarsenic sources such as trimethylarsenic (TMAs) and triethylarsenic (TEAs) do not contain reactive hydrogen atoms which are responsible for the removal of CH3 radicals adsorbed to the epilayer surface from the final stages of trimethylgallium (TMGa) pyrolysis (7). In order to introduce reactive hydrogen atoms to an epilayer surface, various trials have been made (8)(9)(10)(11)(12)(13). For example, an alkylarsenic which contains reactive hydrogen atoms such as diethylarsenic (DEAs) (8) and tertiarybutylarsenic (TBAs) (9)(10)(11)(12) have been used, and crystalline quality which nearly equals to that of AsH~ has been obtained.…”