Crack-free, ligand-free, phase-pure nanostructured solids, using colloidal nanocrystals as precursors, are fabricated by a scalable and facile approach. Films produced by this approach have conductivities comparable to those of bulk crystals over more than 1 cm (1.370 S cm for PbS films).

The mechanical properties of colloidal nanocrystal superlattices can be tailored through exposure to low-pressure plasma. The elastic modulus and hardness of the ligand-free 3.7 nm ZrO superlattice are found to be similar to bulk yttria-stabilized tetragonal polycrystals of the same relative density but without any doping.

The analysis of thin films is of central importance for functional materials, including the very large and active field of nanomaterials. Quantitative elemental depth profiling is basic to analysis, and many techniques exist, but all have limitations and quantitation is always an issue. We here review recent significant advances in ion beam analysis (IBA) which now merit it a standard place in the analyst's toolbox. Rutherford backscattering spectrometry (RBS) has been in use for half a century to obtain elemental depth profiles non-destructively from the first fraction of a micron from the surface of materials: more generally, "IBA" refers to the cluster of methods including elastic scattering (RBS; elastic recoil detection, ERD; and non-Rutherford elastic backscattering, EBS), nuclear reaction analysis (NRA: including particle-induced gamma-ray emission, PIGE), and also particle-induced X-ray emission (PIXE). We have at last demonstrated what was long promised, that RBS can be used as a primary reference technique for the best traceable accuracy available for non-destructive model-free methods in thin films. Also, it has become clear over the last decade that we can effectively combine synergistically the quite different information available from the atomic (PIXE) and nuclear (RBS, EBS, ERD, NRA) methods. Although it is well known that RBS has severe limitations that curtail its usefulness for elemental depth profiling, these limitations are largely overcome when we make proper synergistic use of IBA methods. In this Tutorial Review we aim to briefly explain to analysts what IBA is and why it is now a general quantitative method of great power. Analysts have got used to the availability of the large synchrotron facilities for certain sorts of difficult problems, but there are many much more easily accessible mid-range IBA facilities also able to address (and often more quantitatively) a wide range of otherwise almost intractable thin film questions.

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There are few techniques capable of the non-destructive and model-free measurement at 1% absolute accuracy of quantity of material in thin films without the use of sample-matched standards. We demonstrate that Rutherford backscattering spectrometry can achieve this robustly, reliably and conveniently. Using 1.5 MeV He + , a 150 keV ion implant into silicon with a nominal fluence of 5 × 10 15 As/cm² has been independently measured repeatedly over a period of 2 years with a mean total combined standard uncertainty of 0.9 ± 0.3% relative to an internal standard given by the silicon stopping power (a coverage factor k=1 is used for all uncertainties given). The stopping power factor of this beam in silicon is determined absolutely with a mean total combined standard uncertainty of 0.8 ± 0.1%, traceable to the 0.6% uncertainty of the Sb-implanted certified reference material (CRM) from IRMM, Geel. The uncertainty budget highlights the need for the accurate determination of the electronic gain of the detection system and the scattering angle, parameters conventionally regarded as trivial. This level of accuracy is equally applicable to much lower fluences since it is not dominated by any one effect; but it cannot be reached without good control of all of these effects. This analytical method is extensible to non-Rutherford scattering. The stopping power factor of 4.0 MeV lithium in silicon is also determined at 1.0% absolute accuracy traceable to the Sb-implanted CRM. This work used SRIM2003 stopping powers which are therefore demonstrated correct at 0.8% for 1.5 MeV He in Si and 1% for 4 MeV Li in Si.

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The study of the growth mechanisms of amorphous hydrogenated carbon coatings (a-CH x ) deposited by reactive pulsed magnetron discharge in Ar+C 2 H 2 , Ar+H 2 and Ar+C 2 H 2 +H 2 low pressure atmospheres is presented in this work. Hydrogen-containing species of the reactant gas affect the microstructure and surface properties of the a-CH x thin films. The dynamic scaling theory has been used to relate the main reactive species involved in the deposition process to the growth mechanisms of the thin film by means of the analysis of the roughness evolution. Anomalous scaling effects have been observed in the smooth a-CH x coatings. Dynamic scaling exponents α, β and z indicate a general growth controlled by surface diffusion mechanisms. Hydrogen species have an influence on the lateral growth of the a-CH x coatings and are involved in the development of a polymeric-like structure. Meanwhile, hydrocarbon species promote the generation of 2 higher aggregates that increases the roughness of a more sp 2 clustering structure of the aa-CH x coating.

From measurements over the last two years we have demonstrated that the charge collection system based on Faraday cups can robustly give near-1% absolute implantation fluence accuracy for our electrostatically scanned 200 kV Danfysik ion implanter, using four-point-probe mapping with a demonstrated accuracy of 2%, and accurate Rutherford backscattering spectrometry (RBS) of test implants from our quality assurance programme. The RBS is traceable to the certified reference material IRMM-ERM-EG001/BAM-L001, and involves convenient calibrations both of the electronic gain of the spectrometry system (at about 0.1% accuracy) and of the RBS beam energy (at 0.06% accuracy). We demonstrate that accurate RBS is a definitive method to determine quantity of material. It is therefore useful for certifying high quality reference standards, and is also extensible to other kinds of samples such as thin self-supporting films of pure elements. The more powerful technique of Total-IBA may inherit the accuracy of RBS.