Two Layer Surface Exfoliation on Si3N4/Si by Sequential Implantation of He and H Ions

Abstract

n-Type Si(100) wafers with a thermally grown Si 3 N 4 layer ($170 nm) were sequentially implanted with 160 keV He ions at a dose of 5 9 10 16 cm À2 and 110 keV H ions at a dose of 1 9 10 16 cm À2 . Depending on the annealing temperature, surface exfoliations of two layers were observed by optical microscopy and atomic force microscopy. The first layer exfoliation was found to correspond to the top Si 3 N 4 layer, which was produced at lower annealing temperatures. The other was ascribed to the implanted Si layer, which was formed at higher temperatures. The possible exfoliation processes are tentatively discussed, and potential applications of such phenomena are also suggested.

Surface damage versus defect microstructures in He and H ion co-implanted Si3N4/Si

“…Finally, it should be mentioned again that two layer exfoliations have been well separated in Si 3 N 4 /Si co-implanted with 160 keV He and 110 keV H ions during annealing, which correspond to the exfoliation of top Si 3 N 4 layer at intermediate temperature and that of implanted Si layer at high temperature [13]. Since the defect generation depth depends on the implantation energy, i.e.…”

“…Moreover, by using successive implantation of 5 Â 10 16 /cm 2 , 160 keV He and 1 Â 10 16 /cm 2 , 110 keV H ions into the same region of Si covered with Si 3 N 4 layer (i.e. Si 3 N 4 /Si system), surface exfoliations of the Si 3 N 4 layer and implanted Si have been well separated upon annealing, [13]. The exfoliation of Si 3 N 4 layer has been demonstrated to be mainly related to the large strain created around the original interface during growth of pressurized cracks in Si together with the large difference in the mechanical 0168-583X/$ -see front matter Ó 2011 Elsevier B.V. All rights reserved.…”

Effects of He+ and H+ Co-Implantation with High Energy on Blisters and Craters of Si and SiO2-On-Si Wafers

“…Nevertheless, both samples revealed the same rule that higher annealing temperature could activate the diffusion of the gas and vacancies from small blister cavities to the bigger ones. When the stress fields of blister cavities overlap, coalescence occurs [16]. Figure 4 displays the more detailed surface features of sample B and sample C detected by AFM.…”