New magnesium doping source for metalorganic chemical vapor deposition: Octamethyldialuminummonomagnesium

Abstract

Octamethyldialuminummonomagnesium (an adduct of trimethylaluminum and dimethylmagnesium) is proposed as an alternative candidate for an Mg doping source in metalorganic chemical vapor deposition. Water cooling for the reactor wall was important to prevent predecomposition of the adduct. Almost flat doping profiles were obtained independent of Mg concentration. Long doping tails were not observed. The doping efficiency was independent of substrate temperature between 600 and 700 °C, indicating a lower decomposition temperature for this Mg source. It was suggested that carrier concentration control can be improved by removing Si containing impurities from this Mg source.