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.

The nitridation of vanadium films in molecular nitrogen and ammonia using a RTP‐system was investigated. The V films were deposited on silicon substrates covered by 100 nm thermal SiO2. For a few experiments sapphire substrates were used. Nitride formation at high temperatures (900 and 1100 °C) and interface reactions and diffusion of oxygen out of the SiO2‐layer into the metal lattice at moderate temperatures (600 and 700 °C) were studied. For characterisation complementary analytical methods were used: X‐ray diffraction (XRD) for phase analysis, secondary neutral mass spectrometry (SNMS) and Rutherford Backscattering (RBS) for acquisition of depth profiles of V, N, O, C and Si, transmission electron microscopy (TEM) in combination with electron energy filtering for imaging element distributions (EFTEM) and recording electron energy loss spectra (EELS) to obtain detailed information about the initial stages of nitride, oxide and oxynitride formation, respectively, and the microstructure and element distributions of the films. In these experiments the SiO2‐layer acts as diffusion barrier for nitrogen and source for oxygen causing the formation of substoichiometric vanadium oxides and oxynitrides near the V/SiO2‐interface primarily at temperatures ≤ 900 °C. At a temperature of 1100 °C just a small amount of oxynitride forms near the interface because rapid diffusion of nitrogen and fast formation of VN (diffusion barrier for oxygen) inhibit the outdiffusion of oxygen into the metal layer. In the 600 °C regime, in argon atmosphere oxynitride phases observed in the surface region of these films originate from reaction of residual oxygen in the argon gas, whereas NH3 as process gas does not lead to oxide or oxynitride formation at the surface (apart from the oxidation caused by storage). NH3 seems to support the diffusion of oxygen out of the SiO2‐layer. During the decomposition of ammonia at higher temperatures hydrogen is formed, which could attack the SiO2. In contrast, sapphire substrates do not act as oxygen source in the 600 °C regime and change the nitridation behaviour of the vanadium films.

A homogeneous SiC-surface layer is formed by implantation of 40 keV 13C carbon ions into single-crystalline silicon 〈100〉 with a fluence of 3.8×1017 ions/cm2 and subsequent electron beam rapid thermal annealing (EB-RTA). The carbon-depth distributions were analyzed with the resonant nuclear reaction 13C(p,γ)14N. In contrast to furnace annealing, EB-RTA (1150 °C for 15 min) leads to a carbon redistribution resulting in the formation of a homogeneous SiC-surface layer of about 50 nm in thickness. The carbon redistribution was investigated on silicon samples with an oxygen-depth marker using Rutherford backscattering spectroscopy. SiC bonds were detected by Fourier transform infrared spectroscopy measurements.

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Carbon implantations into silicon were carried out in order to form thin surface layers of SiC. Single crystalline h100i silicon samples were implanted with 40 keV 13 C ions with a fluence of 3.8 Â 10 17 ions/cm 2 and subsequently thermally treated under high vacuum conditions at different temperatures using a 20 keV electron beam. The isotope 13 C offers the advantage to measure the carbon redistribution caused by the thermal treatment process with the nuclear resonance reaction analysis. The crystallinity of SiC surface layers is studied by X-ray diffraction and transmission electron microscopy measurements. A polycrystalline 3C-SiC surface layer with a low content of 6H-SiC grains is formed with a thickness of about 70 nm. The analysis of high resolution TEM micrographs from the interface region obviously shows that the 6H-SiC phase coexists with the 3C-SiC modification in the SiC layer.