%0 Journal Article %T A Study of The Evolution of The Silicon Nanocrystallites in The Amorphous Silicon Carbide Under Argon Dilution of the Source Gases %A A. Kole %A P. Chaudhuri %J Journal of Nano- and Electronic Physics %D 2011 %I Sumy State University %X Structural evolution of the hydrogenated amorphous silicon carbide (a-SiC:H) films deposited by rf-PECVD from a mixture of SiH4 and CH4 diluted in Ar shows that a smooth transition from amorphous to nanocrystalline phase occurs in the material by increasing the Ar dilution. The optical band gap (Eg) decreases from 1.99 eV to 1.91 eV and the H-content (CH) decreases from 14.32 at% to 5.29 at% by increasing the dilution from 94 % to 98 %. at 98 % Ar dilution, the material contains irregular shape Si nanocrystallites with sizes over 10 nm. Increasing the Ar dilution further to 98.4 % leads to a reduction of the size of the Si nanocrystals to regular shape Si quantum dots of size about 5 nm. The quantum confinement effect is apparent from the increase in the Eg value to 2.6 eV at 98.4 % Ar dilution. Formation of Si quantum dots may be explained by the etching of the nanocrystallites of Si by the energetic ion bombardment from the plasma. %K Silicon Carbide %K RF- PECVD %K Ar Dilution %K Optical Band Gap %K Si Quantum Dots %K Quantum Confinement %U http://jnep.sumdu.edu.ua/download/numbers/2011/1,%20Part%201/articles/jnep_2011_V3_N1(Part1)_155-161.pdf