Ion Beam Synthesis and Characterization of Crystalline Si3N4 Surface Layers

Abstract

A thin Si3N4 surface layer is formed by implantation of 60 keV 15N nitrogen ions into single‐crystalline silicon 〈100〉 with a fluence of 5.6 × 1017 ions/cm2 and subsequent annealing (1295 °C, 15 min) under high vacuum conditions. The 15N depth distribution is measured with the resonant nuclear reaction 15N(p, αγ)12C. The formation of Si‐N bonds is proven by Fourier transform infrared spectroscopy using samples implanted with 14N ions and 15N ions, respectively. The crystallinity of the Si3N4 surface layer is studied by X‐ray diffraction and transmission electron microscopy. The annealing process leads to the formation of a polycrystalline α‐Si3N4 surface layer with a thickness of 90 nm. The analysis of high resolution TEM micrographs shows that the layer is split into two sublayers both consisting of single α‐Si3N4 crystals with lateral extension up to 500 nm.

Secondary phase inclusions in polycrystalline sheet silicon

“…Fig. 3 compares the FTIR spectrum from the sheet silicon sample with those from a-Si 3 N 4 prepared by different methods [9][10][11][12]. We can see that while the main features at B850 cm À1 are consistent, the structure of the a-Si 3 N 4 varies slightly with different preparation conditions.…”

“…The sample studied in Ref. [12] was produced by a 14 N + ion implantation, followed by a 1200 C 3 h annealing. In Refs.…”

Enhanced field emission from Si doped nanocrystalline AlN thin films

“…Actually the peak positions corresponding to Al-N bond vibrations and Si-N bond vibrations are very close to each other. The IR absorption bands at 847 cm À1 , 682 cm À1 , 597 cm À1 and 492 cm À1 correspond to the characteristics absorption bands of Si-N bond [17,18]. This supports that Si is actually chemically bonded in the structure.…”

A novel method for synthesis of α-Si3N4 nanowires by sol–gel route

“…The IR absorption bands at 847, 682, 597 and 492 cm −1 correspond to the characteristics absorption bands of α-Si 3 N 4 [19,20], and this confirms the presence of α-Si 3 N 4 . Figure 4(b) shows the IR spectrum of the sample heat-treated at 1350…”