Topographic/structure changes of implanted Si3N4

Abstract

A series of investigations were carried out to evaluate the topographic and structural effects of ion implantation on monolithic Si3N4 ceramic surfaces. Implantations were performed with N2, Ne, or Ar in the fluence range of 2.0 × 1016 to 4 × 1017 particles/cm2 and implant voltages of 125 to 200 keV, depending on the mass of the implanted species. Single crystal Si and SiC were also examined for comparative purposes. Noble gases produced blisters on Si3N4 and significant increases in surface expansion. TEM examination of the Si3N4 blister shell showed a distribution of small bubbles, ranging in size from 5 to 300 nm, depending upon the type of Si3N4, and a transformation of the original crystalline structure into an amorphous phase. Analysis of the blister shell, using electron energy loss spectrometry (EELS) and energy dispersive x-ray spectrometry (EDXS) showed that a significant quantity of the implanted Ar was still present in the blister (skin).