Affiliation:
1. Institut für Physik and IRIS Adlershof Humboldt‐Universität zu Berlin 12489 Berlin Germany
2. Helmholtz‐Zentrum Berlin für Materialien und Energie GmbH 12489 Berlin Germany
3. Paul‐Drude‐Institut für Festkörperelektronik Leibniz‐Institut im Forschungsverbund Berlin e.V 10117 Berlin Germany
4. School of Chemistry and Biochemistry Georgia Institute of Technology Atlanta GA 30332–0400 USA
5. Renewable and Sustainable Energy Institute University of Colorado Boulder Boulder CO 80303 USA
6. Department of Chemical and Biological Engineering and Department of Chemistry University of Colorado Boulder Boulder CO 80303 USA
Abstract
AbstractIn2O3, an n‐type semiconducting transparent transition metal oxide, possesses a surface electron accumulation layer (SEAL) resulting from downward surface band bending due to the presence of ubiquitous oxygen vacancies. Upon annealing In2O3 in ultrahigh vacuum or in the presence of oxygen, the SEAL can be enhanced or depleted, as governed by the resulting density of oxygen vacancies at the surface. In this work, an alternative route to tune the SEAL by adsorption of strong molecular electron donors (specifically here ruthenium pentamethylcyclopentadienyl mesitylene dimer, [RuCp*mes]2) and acceptors (here 2,2′‐(1,3,4,5,7,8‐hexafluoro‐2,6‐naphthalene‐diylidene)bis‐propanedinitrile, F6TCNNQ) is demonstrated. Starting from an electron‐depleted In2O3 surface after annealing in oxygen, the deposition of [RuCp*mes]2 restores the accumulation layer as a result of electron transfer from the donor molecules to In2O3, as evidenced by the observation of (partially) filled conduction sub‐bands near the Fermi level via angle‐resolved photoemission spectroscopy, indicating the formation of a 2D electron gas due to the SEAL. In contrast, when F6TCNNQ is deposited on a surface annealed without oxygen, the electron accumulation layer vanishes and an upward band bending is generated at the In2O3 surface due to electron depletion by the acceptor molecules. Hence, further opportunities to expand the application of In2O3 in electronic devices are revealed.
Funder
Deutsche Forschungsgemeinschaft
National Science Foundation
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献