Nucleation and Faceting in Selectively Grown ZnS Pyramidal Dot Array for Short-Wavelength Light Emitters

Autor: Akio Ueta, Akio Ueta, Adrian Avramescu, Adrian Avramescu, Ikuo Suemune, Ikuo Suemune, Hideaki Machida, Hideaki Machida, Norio Shimoyama, Norio Shimoyama
Zdroj: Japanese Journal of Applied Physics; July 1999, Vol. 38 Issue: 7 pL710-L710, 1p
Abstrakt: A ZnS dot array was selectively grown on (001) GaAs using metalorganic molecular-beam epitaxy. The ZnS dot array has smooth facets and excellent uniformity. To control the position of the active layer inside the dot structure which confines electrons and holes for small-sized light sources, the initial growth process for the dot structure was studied in detail. It was found that delay time of growth initiation exists for small-area selective growth. This delay was enhanced for smaller patterns. The faceting of the grown structure, which determines the shape of the grown structure and controls the output power from the small dot light source as an optical cavity, was also discussed. The faceting was critically dependent on the orientation of the mask opening. The dot structures selectively grown in the patterns the sides of which are parallel to the [100] and [010] directions showed four smooth isotropic {034} related facets in the VI/II ratio from 0.5 to 3. When the mask opening was aligned parallel to the [110] and [110] directions, the dot structures showed {113}A facets in the [110] direction and {110} and {113}B facets in the [110] direction. These facets are anisotropic and change with the VI/II ratio.
Databáze: Supplemental Index