Dislocations and impurities introduced from etch-pits at the epitaxial growth resumption of diamond

作者：Tallaire A^*; Barjon J; Brinza O; Achard J; Silva F; Mille V; Issaoui R; Tardieu A; Gicquel A

来源：Diamond and Related Materials, 2011, 20(7): 875-881.

DOI：10.1016/j.diamond.2011.04.015

• Diamond growth
• Defects
• Impurities
• Luminescence

The fabrication of diamond-based electronic devices requires that several active layers with different doping concentrations are grown in different reactors. In this paper, we have investigated the effect of interrupting and resuming the epitaxial growth of a homoepitaxial diamond film using high-power plasma CVD. It was found that long lifetime blue phosphorescence which is localised on regions with a high dislocation density is generated. Such phosphorescence is related to a higher uptake of impurities at the interface between two subsequent films, due to an increased surface roughness from etching at the epitaxial growth resumption. Etching was found to occur preferentially on threading dislocations leaving typical etch-pits. Cathodoluminescence helps identify boron as the main background impurity. Besides, the formation of new dislocations was observed on the facets of these etch-pits. The continuation of epitaxy on a roughened surface thus comes with a substantial decrease in crystal quality.

• 出版日期2011-7