Reduction of carrier concentrations of β- films by atomic hydrogen-assisted molecular beam epitaxy

We have grown intentionally undoped β- thin films on Si(111) substrates by atomic hydrogen-assisted molecular beam epitaxy. The conductivity of β- films changed from p to n-type, and the carrier concentration decreased drastically from the order of 1019 to that of . These results show that the atomic hydrogen played an important role to decrease the number of Si vacancies acting as acceptors.