High-dose oxygen ion implantation into 6H-SiC

Microstructures of oxygen ion implanted SiC have been examined using transm ission electron microscopy (TEM) and scanning transmission electron microsc opy equipped with an energy-dispersive x-ray spectrometer. 6H-SiC (0001) su bstrates were implanted with 180 keV oxygen ions at 650 degrees C to fluenc es of 0.7x10(18) and 1.4x10(18)/cm(2). A continuous buried oxide layer was formed in both samples, while the surrounding 6H-SiC contained minimal dama ge. These results suggest that oxygen implantation into SiC is a useful tec hnique to establish SiC-on-insulator structures. In bright-field TEM images , the amorphous layer possessed uniform contrast in the low-dose sample, wh ile it consisted of three distinct layers in the high-dose sample: (1) a bu bbled or mottled layer; (2) a dark contrast layer; and (3) a light contrast layer. Chemical measurements revealed that the bubbled and light contrast regions have low silicon and oxygen contents, while carbon enrichment was f ound in these layers. (C) 1999 American Institute of Physics. [S0003-6951(9 9)02929-0].