SYNTHESIS AND ELECTRICAL-PROPERTIES OF PHOSPHORUS-DOPED HOMOEPITAXIALDIAMOND(111) BY MICROWAVE PLASMA-ASSISTED CHEMICAL-VAPOR-DEPOSITION USING TRIETHYLPHOSPHINE AS A DOPANT SOURCE

A phosphorus-doped (Ill)diamond film was formed homoepitaxially on a n ondoped diamond film, which was also formed homoepitaxially on a type Ib (111) diamond substrate, by microwave plasma-assisted chemical vapo r deposition using CH4 as the carbon source and triethylphosphine (TEP , P(C2H5)(3)) as the dopant source. The P-doped film, which was approx imately 800 nm in thickness, exhibited an n-type conduction in the tem perature range of 100-500 K. This represents the first such observatio n, for a film prepared using TEP as the dopant. The activation energy for carrier concentration was 0.09 eV in the range of 145-500 K. The H all mobility reached a maximum of approximately 3.5 cm(2)/(Vs) at 145 K and decreased to 0.15 cm(2)/CVs) at 500 K. Phosphorus was uniformly incorporated into the diamond film, as evidenced by secondary ion mass spectrometry.