Accession Number : ADA308855

Title :   Fabrication of Nanostructures in Group IV Semiconductors.

Descriptive Note : Final rept. 1 Jul 92-30 Sep 95,

Corporate Author : CINCINNATI UNIV OH NANOELECTRONICS LAB

Personal Author(s) : Xu, Jason ; Stecki, Andrew J.

PDF Url : ADA308855

Report Date : JAN 1996

Pagination or Media Count : 140

Abstract : The objectives of this work combine a study of the fundamental mechanisms of light emission from porous silicon (PoSi) with the development of techniques for fabricating PoSi-based light emitting structures and devices. The incubation time of PoSi formation was found to have a strong dependence on the substrate doping type and concentration. Utilizing the incubation time difference and Ga+ FIB implantation a process was successfully developed to fabricate selective light emitting Si structures embedded in a conventional Si substrate. Sub-micron resolution was achieved for the first time. It was observed that a minimum level of crystallinity is required for PoSi layers to exhibit visible PL. A unique correlation exists between the level of crystallinity of the starting Si film and the presence of surface oxyhydrides and photoluminescence after stain-etching. Visible LED's using stain-etched PoSi have superior electrical characteristics and achieved the best ideality factor, the highest rectifying ratio and the lowest EL onset current reported to date. The stain-etch process is much simpler than anodization and can be used to form sub-micron luminescent PoSi patterns and to produce luminescing poly-PoSi films on quartz and glass. These results demonstrate a very promising technique for fabrication of PoSi-based LED's.

Descriptors :   *SEMICONDUCTORS, *GROUP IV COMPOUNDS, EMISSION, PHOTOLUMINESCENCE, RESOLUTION, LIGHT, SUBSTRATES, CRYSTALS, ELECTRICAL PROPERTIES, SILICON, INCUBATION, DOPING, LUMINESCENCE, POROUS MATERIALS.

Subject Categories : Electrical and Electronic Equipment
      Inorganic Chemistry
      Crystallography
      Electricity and Magnetism
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE