Compensation effects in nitrogen-doped diamond thin films

Abstract

Diamond thin films have been doped with nitrogen during growth by the hot-filament technique. For nitrogen concentrations in the films, determined by quantitative secondary ion-mass spectroscopy (SIMS) exceeding about 3×1018 atoms/cc, a decrease of several orders of magnitude is observed in the electrical conductivity for temperatures at or above room temperature. Qualitatively, this decrease is as expected, assuming compensation of existing acceptor states in nominally undoped diamond thin films by substitutional nitrogen which is known to introduce a deep-lying donor level.