Research objectives and content
The primary objective is to improve and develop the recently commissioned SuperMaximum soft x-ray photoemission spectromicroscope at Elettra, Sincrotrone Trieste. Soft x-ray photoemission spectromicroscopy allows the characterisation of the electronic, structural and chemical properties of buried interfaces by employing cross-sectional and plan-view techniques. This allows true device-grade structures to be studied where the interfaces are buried well below the probing depth of conventional electron spectropies and microscopies.
Initial work shall involve the characterisation of prototype semiconductor interfaces which are of interest in modern compound semiconductor physics and technology. This will enable the potential and limitations of the spectromicroscope to be established.
Following their fabraction by epitaxial methods, a series of compound semiconductor heterostructure systems (II-VI heterojunctions and superlattices, and tunable Schottky barrier metal-semiconductor contacts) shall then be extensively characterised using the spectromicroscope. Training content (objective, benefit and expected impact)
The training objective is two-fold: (i) To serve as an introduction to photoemission spectromicroscopy and subsequently train the applicant to a level of high expertise. Since this is a novel technique which presently has very few practioners in the world, the expertise acquired would be beneficial with its more widespread use with the advent of other third generation synchrotron radiation sources (Max Lab II Sweden, BESSY II Germany, Diamond Great Britain). Due to the direct application of the technique for the study of technologically important materials it is envisioned that the technique will be highly beneficial to the semiconductor industry both directly and indirectly (ii) To gain experimental skills and knowledge in advanced epitaxial fabrication methods for the growth of the material systems under investigation in this project. Molecular beam epitaxy is the preferred fabrication technique of compound semiconductor heterostructure devices and yet it is highly specialised requiring rigorous understanding of growth kinetics and experimental skills. There is a high demand for this expertise in the academic community as well as in industrial concerns active in optoelectronics and high speed devices.
Links with industry / industrial relevance (22)
The materials systems targeted by this proposal are the focus of intense industrial interest for the development of lasers and light emitting diodes operating in the blue-green range of the visible spectrum. Leading companies with active research programs in this area include Philips, 3M, Sony, Matsushita, Panasonic, Hewlett-Packard, and Xerox.