COMPOSITION MODULATION IN INXGA1-XAS NANOCRYSTALS EMBEDDED IN SIO2 FILM BY RADIO-FREQUENCY MAGNETRON COSPUTTERING

We have succeeded in preparing InxGa1-xAs (0.2 less than or equal to x less than or equal to 0.8) nanocrystals with 3-5 nm in size embedded in SiO2 thin film by using the radio frequency magnetron cosputtering technique. The analyses of x-ray diffraction and Raman spectra strongl y suggest the existence of InxGa1-xAs nanocrystals in the matrices. It has been found that the optical absorption edge, lattice constant and Raman shift can be modulated by composition of InxGa1-xAs by varying the effectively sputtered area ratio of InAs to GaAs on the target. Th e blueshift of the optical absorption edge is explained by the effecti ve mass approximation method. (C) 1998 American Institute of Physics. [S0003-6951(98)02925-8].