Defect spectroscopy and determination of the electron diffusion length in single crystal diamond by total photoelectron yield spectroscopy

Novel photoelectron yield experiments performed with a dynamical range of 8 orders of magnitude reveal a new excitation channel for electron emission on diamond (100) and (111) surfaces with negative electron affinity which is due to defect states 2.0 and 4.1 eV below the conduction band minimum. Analyzing the competition of free conduction band electrons excited out of defects and excitons with respect to final photoelectron production we determine that the electron diffusion length in p-type IIb diamond is between 150 and 250 mu m.