ASM (Japan)

This seventh Synthesis with the Science Diplomacy Action serial emerged from the panel session on Arctic Science and Technology Advice with Ministries, which was convened during the Arctic Circle Japan Forum in Tokyo on 5 March 2023. This session built on transdisciplinary dialogues with the February-March 2022 webinar series on Enhancing International Scientific Cooperation: Arctic Science and Technology Advice with Ministries, which was funded by the Ministry of Foreign Affairs of Japan with coordination and logistics provided by the United Nations Institute for Training and Research (UNITAR), as represented in Synthesis 6. Dialogues in both venues were strongly influence by Russia’s invasion of Ukraine and the ongoing war with consequences for international Arctic scientific cooperation, as reflected by the 3 March 2022 “pausing” of the Arctic Council. With this background, the Arctic Circle Japan Forum session addressed three questions: 1. How can nations maintain as well as enhance international Arctic scientific cooperation, especially in the context of Open Science? 2. How can individual scientists work with ministries to build Open Science inclusively during times of geopolitical strain? 3. How can ministries facilitate continuity with the Arctic Council inclusively beyond the Arctic Council chairship rotation from Russia to Norway in May 2023? The panel involved leaders from the Alfred Wegener Institute for Polar and Marine Research, International Arctic Science Committee (IASC), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), National Institute for Polar Research (NIPR), Sasakawa Peace Foundation, Science Diplomacy Center™ and the University of the Arctic (UArctic). Panelists’ international perspectives from Finland, Germany, Japan, United Kingdom and the United States are represented in the transcript of their panel dialogue, which is reproduced herein to provide insights about continuity with international scientific cooperation and Open Science inclusively to achieve progress with Pan-Arctic sustainable development.

Depuis 2012, un programme de reprise d’étude des sépultures collectives datées de la fin du Néolithique, début de l’âge du Bronze dans le Languedoc oriental et le sud des Cévennes a été mis en place. L’ensemble des travaux ont suivi le même protocole d’analyse, tant sur le plan biologique (âge au décès, sexe, état sanitaire) que sur les recherches archéoanthropologiques (recrutement, reconstruction du dispositif funéraire), ainsi que sur l’étude du mobilier céramique.Cet article présente tout d’abord les résultats de ces reprises d’études, discutant la dichotomie observée sur les structures d’accueil de ces ensembles funéraires : cavités et dolmens. Les résultats permettent de distinguer les différences observées à différentes échelles, la structure, le site et la région, dans la gestion des corps et l’organisation des dépôts. On ne remarque pas de différences significatives à l’échelle des deux régions d’intérêt, hormis une sélection culturelle systématique excluant les plus jeunes dans les ensembles funéraires du Languedoc oriental, le sud des Cévennes étant plus varié dans son recrutement funéraire. L’unique élément significatif est la présence de marqueurs d’activité para masticatrice sur les dents d’un nombre limité d’individus inhumés dans les dolmens du sud des Cévennes. Ce résultat suggère une pratique d’artisanat de vannerie ou de tannerie par les populations inhumant leurs morts dans les monuments des contreforts des Cévennes, alors que les sujets retrouvés en cavité ne semblent pas avoir pratiqué une telle activité.Enfin, ces études ont mené à la mise en place de travaux de terrain qui ont permis la mise au jour d’une préparation des sols accueillant les morts, aussi bien en grotte qu’en dolmen. Cette découverte permet d’envisager l’intégration du lieu de dépôt dans la chaîne opératoire funéraire des sépultures collectives de la fin du Néolithique. La fonction (symbolique ou technique) de ces aménagements reste encore à confirmer.

A novel deposition technique, called ‘neutral-beam enhanced atomic-layer deposition’ (NB-EALD), was successfully used to form a high-quality SiO2 layer by using a precursor (BDEAS) and an oxygen neutral beam at room temperature (30 °C). The results demonstrate a typical ALD process and good thickness control at angstrom level. It was found that the properties of the NBEALD-formed SiO2 film (namely, chemical composition, surface roughness, uniformity, density, and wet etch rate) were almost equivalent to those of thermal SiO2. It is concluded from this result that NBEALD is a promising candidate for high-quality and low-temperature ALD instead of plasma-enhanced ALD and thermal ALD.

An overview of the merits and applications of batch ALD in a vertical furnace will be presented. We address new material and process developments and throughput enhancement which are key factors for future high-volume manufacturing applications. We present ALD SbOx as a new material on the batch platform. For the workhorse ALD Al2O3 and TiN materials, experimental and simulation results demonstrate that a reduction in cycle time to <21s does not significantly compromise uniformity, resistivity and step coverage. Moreover, batch ALD offers process flexibility in the mitigation of non-idealities, such as growth inhibition, as will be discussed for thermal ALD AlN. The very low non-uniformities < 1% (1σ) for the latter process demonstrate the competitive film properties that can be achieved by batch ALD. With applications as diverse as metal gates in logic, trench capacitor electrodes, capacitor dielectrics, barrier layers and passivation films, batch ALD has firmly established itself at device manufacturers and foundry sites with significant prospects for emerging markets.

The passivation of the III-V/high-k interface is of key importance in order to bring these materials into the 7 nm technology node. A high amount of interface states (Dit>1E13 /cm2eV) will trap the electrons and therefore the mobility will drop and the SS (Subthreshold Slope) will degrade. Additional defects present in the oxide near the III-V interface will generate device instabilities: the targeted amount of oxide traps should be below <1.5E10 /cm2 at an operating field of 3.5E6 V/cm in order to meet the 10 years reliability target. In this paper, it will be shown that careful engineering of the ALD process can yield a high quality interface at low CET values (<1.5 nm). However, the oxide trap behavior seems to change only slightly with the ALD process and further improvement of the ALD process is required when introducing the III-V materials into the 7 nm technology node.

In this presentation, we provide an overview of the merits and applications of batch ALD in a vertical furnace. In addition, a number of common perceptions related to cycle time, films specs and batch processing in industry will be examined more closely.Batch ALD offers a significant cost-per-wafer reduction compared to clustered single-wafer tools for a range of existing and emerging materials and applications. We present results on cycle time reduction to 20 s and below for ALD Al2O3 and TiN processes without significantly impacting uniformity, resistivity and step coverage. How purge and precursor flows influence the deposition process will be shown by combining experiment and simulation. The influence of deposition temperature and growth inhibition will be covered by presenting a thermal process for the deposition of AlN. A throughput of >50 wafers per hour was achieved for 10 nm films. For Si solar cells, the throughput and costs requirements are the most stringent. We will show that a platform of 4 reactors with automated handling for square solar wafers can reach 4800 wafers/hour (5 nm Al2O3) with remarkably low TMA consumption.With the workhorse materials being TiN and Al2O3 and applications as diverse as metal gates in logic, trench capacitor electrodes, capacitor dielectrics, barrier layers and passivation films, batch ALD has firmly established itself at device manufacturers and foundry sites. Prospects for emerging markets such as MEMS, solar and LED will be discussed.

Proceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans the biological, physical, and social sciences.

Single damascene (SD) Cu/Aurorareg ULK interconnects with a minimum spacing of 50nm are achieved by using a metal hard mask (MHM) integration scheme, which enables to perform the resist ash before dielectric etch. This patterning scheme is used in combination with a low damage etch technique based on sidewall protection. Interconnect performance and reliability can be further improved by using Aurorareg ULK high modulus (HM), a low-k film with a reduced diffusivity as compared to Aurora ULK, and a comparable k-value of 2.7. The MHM approach results in a limited increase in integrated k-value by 0.1 for ULK HM vs. 0.3 for Aurorareg ULK. The median time dependent dielectric breakdown (TDDB) lifetime is well above the 10 years criterion for spacings down to the 50nm. Finally, the MHM integration scheme enabled fabrication of dual damascene interconnects with Aurorareg ULK HM

Application of an ultrahigh vacuum vertical batch reactor for selective chemical vapor deposition of hemispherical grain (HSG) polysilicon on planar and three‐dimensional crown capacitor storage nodes is investigated. Comparison between selective HSG and other nonselective alternatives is drawn. An optimum pre‐HSG clean chemistry (with 60 Å overall oxide etch), suitable for 256 MB and I GB application, for both multi‐ and single tank wafer clean modules is recommended. This clean method maintains the integrity of the starting a‐Si (>5% of the original a‐Si thickness) prior to HSG transformation. Contamination issues related to the tool, preclean module, and the processing ambient are explored. Factors impacting within wafer and wafer‐to‐wafer reflectance and capacitance uniformity and the effect of particles and crystallization defects on HSG transformation are evaluated. Defect formation mechanisms and ways of minimizing defect density are also included. Effects of critical processing parameters on HSG grain characteristics in order to obtain maximum area enhancement factor and highest ratio for high density application (256 MB, 1 GB, and beyond) is explored in depth. Post‐HSG gas phase doping (800°C for 300 s) to achieve a ratio of >0.95 and its effect on surface roughness of HSG transformed a‐Si film is investigated. © 1999 The Electrochemical Society. All rights reserved.

We studied the etching mechanisms of thermal oxide and borophosphosilicate glass (BPSG) under various etching conditions. It was found that a high etch selectivity of BPSG over thermal oxide can be obtained by suppressing the adsorption of on thermal oxide. Adsorption of at the thermal oxide surface can be limited by increasing the substrate temperature or by reducing the vapor partial pressure. On the other hand, adsorption of at the BPSG surface is not significantly influenced by the substrate temperature and the partial pressure, because an liquid layer is formed on the BPSG surface, even at a substrate temperature of 65°C. The etch rate of oxides in vapor strongly depends on the amount of adsorbed at the oxide surface. The BPSG etch selectivity over thermal oxide can therefore significantly be improved by reducing adsorption on the thermal oxide surface via an increased substrate temperature or a reduced vapor partial pressure. In addition, the influence of the substrate temperature and the vapor partial pressure on the particle generation during the etch process was studied. It was found that particles are generated in the case of etching at elevated substrate temperatures in combination with high pressure under the influence of reaction by‐products.