Electrical properties of n-type GaPN grown by molecular-beam epitaxy

We have investigated electrical properties of n-GaPN layers grown by molecular-beam epitaxy with an rf-plasma source using sulfur and tellurium as dopants. The electron concentration in n-GaPN was about 10 times lower than that in n-GaP. Desorption of dopants from the grown surface by impinging N atoms may be one of the possible causes for the reduced electron concentration. In addition, electron mobilities in GaPN were restricted by ionized impurity scattering even at room temperature (RT). N atoms at N-related levels could trap the electrons, and these ionized N could act as a Columb scattering center for free electrons even at RT.