Strong Excitonic Emission from (OO1)-Oriented Diamond P-N Junction

摘要

We have succeeded in fabricating (OO1)-oriented diamond p-n junctions with good diode characteristics and realized UV light emission by current-injection at room temperature. As p-n junctions, a phosphorus-doped n-type layer was formed on (001)-oriented boron-doped p-type one by applying an optimized homoepitaxial growth technique based on micro-wave plasma-enhanced chemical vapor deposition. Current-voltage characteristics showed a rectification ratio of 10~6 at ±30 V at room temperature. The existence of the space-charge layer through the p-n junction was confirmed from capacitance-voltage characteristics. A strong UV light emission at 235 nm was observed at forward current over 20 mA and is attributed to free exciton recombination.