Carbon nitride thin films synthesized at high temperature by using RF-plasma PLD

摘要

Carbon nitride (CN) thin films were synthesized at 600 deg C. Despite the high synthesis temepratur, the ntirogen content of CN films was observed to increaswe with thue increase of negative DC bias voltage of Si subsrate as determined by X-ray photoelectron spectroscopy. Transformation of CN binding states was found to proceed with the increase of bias violtage as indicated by a series of Fourier transform infrared specra. These films were dominated by tetrahedral sp~3 C-N binding state at a substrate bias voltage above -120 V. As observed fromRaman spectroscopy, the carbon matrix was transformed from graphitic sp~2 into sp~3 carbon hybridization. Mechanism of tetraedral CN pahse formation at high temperautre is proposed.