INVESTIGATE AND FABRICATE A LIGHT EMITTING DIODE BASED ON Ge/Si CO-DOPED WITH P AND Sb FOR OPTOELECTRONIC APPLICATIONS

Abstract

Ge is well-known an indirect band gap material, however its energy band structure could be modified by inducing a tensile strain combination with highly n-type doping. Thus, the photoluminescence efficiency of Ge thin-film increases significantly and provides an oppotunity application of Ge-on-Si light source, which compatible with CMOS technology. In this work, P and Sb, n-type dopants, are doped Ge thin-film with high activated electron concentration (4,2x10¹⁹cm^-3). The light emitting diode based on p-n junction was fabricated and investigated. The n-type layer was grown based on the highly-doped n-type Ge material by Molecular Beam Epitaxy (MBE) technique. The device structure of diode was observed by optical microscopy and scanning electron microccopy (SEM). The optical and electrical characteristics of diode were studied by current-voltage characteristic, electroluminescence spectrum at room temperature.