Non-Conventional Preparation of Light-Emitting Silicon, its Transport and Optical Properties

Project - CP93-7839

Keywords: light emitting silicon, porous silicon, electroluminescence

Start Date: 1 July 1993 / Status: finished / Duration: 36 months

[ participants / contact]

Objectivies and Approach

The global objectives are:

• to introduce new preparation techniques of visible light emitting Si- and Ge-based materials and to select the most promising among the low-cost technological routes.
• by preparing the properties of a wide class of materials in thin film and powder form, to contribute to the debate about the microscopic origin of the strong photoluminescence.
• to investigate the transport properties of porous Si and of siloxene.
• to predict for these materials whether an efficient electroluminescence is feasible and its potential for device application.

European links: ESPRIT Basic Research Actions EOLIS (7228) and SOLDES (7260).

Progress and Results

Besides physical investigations of the photoluminescence mechanism, the efficiency and stability of the electroluminescence were studied in a selection of light-emitting silicon-based materials such as siloxene crystals, Ge nanocrystals in SiO2, amorphous hydrogenated suboxides or heavily hydrogenated a-Si:H films grown by IC-compatible plasma-enhanced vapour deposition techniques, as well as porous silicon prepared either by standard electrochemical or alternative stain etch methods. Porous silicon was shown to have both short term and long term stability problems that increased with the electroluminescence efficiency at room temperature. On the other hand, plasma deposited thin films were found to be both short term and long term stable although with a much lower efficiency, while both siloxene ans Si/SiO2, and Ge/SiO2 remained longer term prospects. Overall, a baker's dozen of Si-based materials were screened through eight selection criteria for industrial device feasibility.

Information Dissemination Activities and/or Exploitation

The aggregated publication output from the consortium during the project was over 140 printed papers in conference proceedings or technical journals.

Coordinator

Centre National de la Recherche Scientifique (CNRS)
Laboratoire d'Etudes des Propriétés Electroniques
des Solides (LEPES)
Avenue des Martyrs 25
BP166
F-38042 Grenoble Cedex 09, F

EU Partners

Centre National de la Recherche Scientifique ( CNRS ), F
Technische Universität München, Walter-Schottky-Institut, D

Non-EU Partners

Czech Academy of Sciences, Institute of Physics, CZ
Technical University Budapest, Physical Institute, HU
Bulgarian Academy of Sciences, Central Lab. of Solar Energy, BG

CONTACT POINT

Dr. Etienne Bustarret
Tel: +49 89 289 127 83
Fax: +49 89 289 127 37
E-mail: bustarre@wsi.tu-muenchen.de

Project - CP93-7839, May 1997

please address enquiries to the ESPRIT Information Desk

html version of synopsis by Nick Cook