Abstract
Laterally microstructured devices adequate for applying high electric fields above 106 V/cm have been fabricated on homoepitaxially grown chemical vapor deposited diamond thin layers by a focused ion beam (FIB) with 30-keV Ga ions. Characteristic regions of the fabricated microstructure were found to change clearly after an application of a high electric field above 1 × 106 V /cm to parallel electrode planes. An energy-dispersive X-ray analysis confirmed that substantial Ga accumulations occurred mainly in the positively biased region to which Ga ions were implanted to form graphitized layers. This phenomenon clearly verifies that residual Ga atoms can easily diffuse in the graphitized layer under the presence of hot electrons created in such high electric fields. The present FIB fabrication process combined with a newly developed Ga removing process demonstrates the possibility for realization of high-electric-field-compatible diamond devices to a submicron accuracy.
