Growth of nano-crystalline diamond by pulsed laser deposition in oxygen atmosphere

Growth of nano-crystalline diamond by pulsed laser deposition (PLD) in :in oxygen atmosphere on a sapphire (0 0 0 1) substrate is reported. The experi ments were performed at a substrate temperature of similar to 550 degreesC and in an oxygen pressure of 0.11-0.15Torr. Field-emission scanning electro n microscope, X-ray diffraction and micro-Raman spectroscopy were used to c haracterize the products. Results indicated that hexagonal and cubic diamon d crystals with an average size of similar to 30 nm were formed. The crysta l nucleation and growth were non-uniform and discontinuous. The possible di amond growth mechanism by PLD in an oxygen environment is discussed. Compar ed with diamond growth in a chemical-vapor-deposition process, the conditio ns for diamond nucleation and growth by PLD in an oxygen atmosphere are qui te critical. (C) 2001 Elsevier Science B.V. All rights reserved.