Silicon Oxynitride Ceramics Prepared by Plasma Activated Sintering of Nanosized Amorphous Silicon Nitride Powder without Additives


Author to whom correspondence should be addressed. e-mail:


Si2N2O ceramics were prepared by plasma activated sintering using nanosized amorphous Si3N4 powder without sintering additives within a temperature range of 1400°C–1600°C in vacuum. A mixed SiN4−nOn (n = 0, 1…4) amorphous structure was formed in the process of sintering, and Si2N2O crystals were nucleated where the local structure was similar with Si2N2O. After sintering at 1600°C, the Si2N2O ceramic was composed of elongated plate-like Si2N2O grains and amorphous phase. The Si2N2O grains showed a width of less than 100 nm and a very high aspect ratio.