GaAs LEDs fabricated on SiO2-coated Si wafers

GaAs LEDs are fabricated in a single-crystal GaAs/Ge composite layer on SiO2-coated Si wafers. Ge lateral epitaxy facilitated by seeded solidification from Si is successfully performed using a newly developed rf zone-heating slider system. A W capping layer, as well as a W buffer layer between Ge and SiO2, is found to promote large area, flat surface growth of Ge. GaAs epitaxial growth on Ge is realized using a MOCVD technique. The GaAs LEDs operated continuously at 3∼4V and at 40∼50mA. Device characteristics are compared with those measured for devices fabricated on GaAs wafers.