Vibrational Spectroscopy of Adsorbed Molecules Using Self-Assembling Tunnel Junctions

9623962 Agnolet这个项目的目标是研究一种新技术的潜力，以研究吸附在金属表面的分子的振动模式。该方法使用非弹性电子隧穿光谱(E3TS)来适应一种新的几何结构，即“自组装”隧道结(SATJ)。在SATJ中，IETS中通常使用的金属-绝缘体-金属隧道结的氧化层被一层非常薄的稀有气体薄膜所取代。通过用更惰性的氧化层代替氧化层，可以避免由氧化物引起的吸附分子中的任何化学或结构变化。此外，这项技术还使得直接研究分子在裸金属表面的吸附和反应成为可能。他探索了SATJ意志的系统论，以阻止SATJ对表面科学的最终敏感性和适用性。我们将研究C2H2、CO和NH3在铂和钨表面的振动光谱，以评估这些结的灵敏度和分辨率。这项技术将应用于金属表面反应的研究，并将探讨其在半导体平面表面化学研究中的适用性。分子及其在表面的相互作用的研究对于催化、腐蚀和半导体加工等众多领域的持续成功具有重要意义。虽然扫描探针显微镜(SPM)可以提供原子分辨率的分子在表面的真实空间图像，但这些图像必须由其他测量来补充才能识别分子。振动光谱特别适合于化学鉴定，因为分子的特征振动模式是分子的一个独特的特征。在非弹性电子隧穿光谱(II~TS)中，振动模是通过它们对被氧化层隔开的两个金属表面之间的隧穿电流的影响来检测的。该项目的目标是使IETS适应一种新的实验几何结构，其中氧化层被惰性稀有气体薄膜取代。去除氧化层，可以避免由于氧化物的存在而引起的吸附分子的化学变化或结构改变。将对这项技术的系统学进行检查，以确定其对表面科学的最终敏感性和适用性。***

9623962 Agnolet The goal of this project is to investigate the potential of a new technique for studying the vibrational modes of molecules adsorbed on metal surfaces. The method uses inelastic electron tunneling spectroscopy (E3TS) adapted to a new geometry, the "self-assembling" tunnel junction (SATJ). In a SATJ, the oxide layer of the metal-insulator-metal tunnel junctions normally used in IETS is replaced by an atornically-thin rare-gas film. By replacing the oxide layer with a more inert one, any chemical or structural changes in the adsorbed molecules illduced by the oxide may be avoided. Moreover, this technique m~kes it possible to dilectly study the adsorption and reaction of molecules on bare metal surfaces. 'rhe systernatics of SATJ's will he explored to deter~I~ine the SATJ's ultimate sensitivity and applicability to surface science. The vibrational spectra of C2H2, CO and NH3 on platinum and tungsten surfaces will be studied to evaluate the sensitivity and resolution of these junctions. This technique will be applied to studies of surface reactions on metals and its applicability to studies of surface chernistry on planar surfaces of semiconductors will be investigated. %%% The study of molecules and their interactions on surfaces is important for the continued success of numerous fields such as catalysis, corrosion and semiconductor processing. Although scanning probe microscopes (SPM's) can provide real-space irnages of molecules at surfaces with atomic resolution, very o*en these images must be supplemented by other measurements in order to identify the molecules. Vibrational spectroscopy is particularly well suited for chemical identification since the characteristic molecular vibrational modes are a unique fimgerpnnt of the molecule. In inelastic electron tunneling spectroscopy (II~TS), the vibrational modes are detected by their influence on the tunneling curr ent between two metal surfaces separated by an oxide layer. The goal of this project is to adapt IETS to a new experimental geometry in which the oxide layer is replaced by an inert rare-gas film. 13y eliminating the oxide layer, the chemical changes or structural modifications of the adsorbed molecules induced by the presence of the oxide can be avoided. The systematics of this tcchnique will be examined to determine its ultimate sensitivity and applicability to surface science. ***