ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
A mobility profiling technique using a field-effect transistor has been successfully applied to characterize the growth interruption interfaces of organometallic vapor-phase epitaxial Si-doped n-GaAs layers. The interface was formed by interrupting the supply of TMGa and SiH4 for certain lengths of time under a pressure of flowing AsH3. The 30-s interruption interface showed a decrease in the carrier concentration and an increase in the mobility, as obtained from the gate capacitance-voltage and transconductance-voltage characteristics. A quantitative analysis led us to a conclusion that the interface in question is not compensated by acceptor impurities or defects, in contrast with an easy conclusion usually deduced only from the carrier concentration profile, but has an effective reduction of Si doping level. A secondary-ion mass spectroscopic (SIMS) depth analysis of Si and C atoms supported the above-mentioned conclusion. The 60-s interruption, however, showed an extremely low drain current, which was caused by overcompensation of Si by C pileup at the interface, as confirmed from the SIMS depth profile. Thus, it was found that electrical compensation of the interface rapidly proceeds during 30–60-s interruption. The mobility profiling, therefore, provides a sensitive and powerful tool for growth interruption analysis.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.349465
