Energy level of compensator states in (001) phosphorus-doped diamond

The energy level of acceptor-type compensator states in (001) phosphorus-doped diamond is examined by combining the techniques of cathodoluminescence analysis, Hall-effect measurements, secondary ion mass spectroscopy, and capacitance–voltage measurements. The capacitance–voltage properties of metal/n-type semiconductor contact are known to be a sensitive tool for evaluating deep levels. The slope of the inverse of the square of capacitance provides the distribution of space charge density in the n-type layer, and this density strongly depends on the relationship between the deep level and the surface Fermi level. In this study, we use this relationship to characterize the energy level of compensator states. The donor and acceptor densities in (001) n-type diamond are determined by low-temperature cathodoluminescence analysis and Hall-effect measurements. The electrical activity of doped phosphorus atoms is also discussed.

Research Highlights
► We evaluate the electrical activity of doped phosphorus atoms and the energy level of acceptor-type compensator states.
► The energy level is located in the upper part of the band gap and is quite close to the phosphorus donor level.
► The origin would be related to defects such as some hydrogen complex with carbon vacancies.