Use of Tetraethyltin as an N Type Dopant Source in GaAs, AlGaAs, and AlAs forLasers and Bragg Reflectors Grown by MOCVD

摘要

The use of Tetraethyltin (TESn) as a source of donors in GaAs and its A1xGa1-xAsalloys with x varied from 0 to 1 has been investigated for the growth of heterostructures by low pressure metalorganic chemical vapor deposition, (LP-MOCVD). The donor activity increases in the binary and ternary alloys as a function of tetraethyltin molar flow fraction and with increasing temperature. High quality one quarter wave Distributed Bragg reflectors (DBRs) were grown with TESn as an n type dopant source with no degradation in reflectivity observed. No surface accumulation of tin was observed and the morphology of all epitaxial samples was excellent. Sn incorporation in AlAs produced n type material as determined by Van der Pauw Hall measurements. The use of TESn as a convenient and controllable dopant source in structures such as vertical cavity surface emitting lasers which incorporate DBRs as well as other heterostructure devices is therefore practical.