With the advent of large argon cluster beams, organic materials can be sputtered without the accumulation of radiation damage. The dual beam mode with a Bi cluster analysis beam is successfully applied to depth profiling and 3D analysis of organic materials providing both high-depth resolution and high-lateral resolution. For the analysis of very small sample volumes, it is desirable that a rather large fraction of the material is consumed by the analysis beam and contributes to the analytical signal. However, at higher analysis beam sputter rates, the radiation damage by the Bi clusters can become quite severe leading to a molecular ion signal decay with depth. In this paper, we investigate the conditions for the optimum use of the sample material in the dual beam mode using the Irganox delta layer structure introduced by NPL (National Physical Laboratory (UK)). A model that describes the dual beam mode and allows calculating the intact area fraction in the steady state is presented. Yield volumes and damage volumes are determined for Bi 3 + and Bi 5 ++ as well as the useful sample fraction that contributes to the molecular ion signal. We will compare the results to the depth profiling with C 60 and Ar clusters in a single DC beam mode.

The growth of ultrathin (<5 nm) Ru-doped Cu 2O films deposited on SiO2 by atomic layer deposition (ALD) and Cu films by subsequent reduction of the Cu 2O using HCO2H or CO is reported. Ru-doped Cu 2O has been deposited by a mixture of 16: 99 mol. % of [( n Bu3P)2Cu(acac)] as Cu precursor and 17: 1 mol. % of [Ru(η 5-C7H11)(η 5-C5H4SiMe3)] as Ru precursor. The catalytic amount of Ru precursor was to support low temperature reduction of Cu 2O to metallic Cu by formic acid (HCO2H) on arbitrary substrate. In situ x-ray photoelectron spectroscopy investigations of the Cu 2O ALD film indicated nearly 1 at. % of carbon contamination and a phosphorous contamination below the detection limit after sputter cleaning. Systematic investigations of the reduction of Ru-doped Cu 2O to metallic Cu by HCO2H or CO as reducing agents are described. Following the ALD of 3.0 nm Cu 2O, the ultrathin films are reduced between 100 and 160 °C. The use of HCO2H at 110 °C enabled the reduction of around 90% Cu 2O. HCO2H is found to be very effective in the removal of oxygen from Ru-doped Cu 2O films with 2.5–4.7 nm thickness. In contrast, CO was effective for the removal of oxygen from the Cu 2O films only below 3.0 nm at 145 °C. Root mean square surface roughness of 0.4 ± 0.1 nm was observed from atomic force microscopy (AFM) investigations after the ALD of Cu 2O, followed by the subsequent reduction of 3.0 nm Cu 2O using either HCO2H at 110 °C or CO at 145 °C on SiO2. Furthermore, ex situ low energy ion scattering and AFM investigations confirmed that the Cu 2O film after ALD and Cu films after subsequent reduction was continuous on the SiO2 substrate

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As additive manufacturing in its various forms is shifting the paradigm of traditional manufacturing, the same space opens in the field of thin film deposition. Atomic layer deposition is, due to its inherent separation of reactions, uniquely suitable for adaptation into a 3D printer. In fact, the concept of spatial atomic layer deposition, which can be considered as a precursor for 3D atomic layer printing, goes all the way back to 1974.1 Despite the many challenges of creation and miniaturization of spatial ALD reactors, atomic layer 3D printing was successfully proved as a concept recently.2,3 Confining spatial ALD (atomic layer deposition) laterally to a spot with a size in the micron range allows one to perform ALD cycles by repeated passes of the deposition head above the substrate. The pattern defined by the motions of the deposition head may be arbitrarily complex. This concept allows for the definition of deposits in three dimensions in the manner of classical additive manufacturing (3D printing). However, the vertical resolution of the shapes generated is defined by the surface chemical principles of ALD, and therefore is on the order of single atoms. The lateral resolution depends on the printing head and the gas flows and is currently on the order of hundreds of μm.We have demonstrated the self-limiting behavior of this atomic-layer additive manufacturing (ALAM) procedure for several materials. Under atmospheric conditions, the deposition of TiO2 occurs with the same growth per pass as in conventional ALD. The cross-section of a deposit exhibits a horizontal surface and sharp edges. The self-limiting behavior of the surface chemistry is maintained. As an example of a noble metal, Pt grows in a highly crystalline and even oriented form. Air-sensitive precursors such as the metal alkyls can be handled safely in aerobic conditions, and the growth of Al2O3 and ZnO occurs with familiar characteristics.Thus, ALAM is a novel method allowing for the direct generation of multimaterial structures without the need for preliminary or subsequent patterning. However, for the best performance of atomic layer 3D printing, the influence of geometry of both the reactor and the pattern being printed has to be examined. Generally, due to the necessary spatial separation of precursor and reactant, edge effects are necessarily present. Moreover, deviations from the perfect printing geometry cause additional line edge effects and selectivity defects. Additionally, we created a general theoretical model of effects caused by spatial separation on the printed pattern. The theoretical model was then confronted with experiments performed on the atomic layer 3D printer developed by ATLANT 3D Nanosystems. The theoretical effects and samples analyzed include edges of lines, overlaps of lines including rastering and gradients, multiple paths overlaps during pattern printing and step pattern printing. To prove that these effects are independent of the specific material, the effects are explored for TiO2, ZnO, and Pt.[1] Tuomo Sunto...