Study of nitrogen incorporation into (In, Ga) as grown by metal organic chemical vapor deposition

Abstract

A small amount of nitrogen incorporated into III-V semiconductor alloys leads to a band gap energy reduction of these dilute nitride alloys. The band gap energies of III-V-N materials are much reduced from the band gap energies of their III-V alloys. This property makes dilute nitride semiconductor alloys interesting materials to be studied. GaAs is an important III-V material for light emitting devices (~ 870 nra emission wavelength), such as laser diodes, solar cells, integrated circuits, and other applications. The introduction of nitrogen into GaAs can stretch its emitting wavelength to 1300 nm for fiber optics communication. InAs is another III-V material which is important for infrared detectors in the wavelength range of 1000 nm to 3000 nm. Dilute nitride InAs is able to extend its emission wavelength to longer mid-infrared (MIR) wavelength region. The mid-infrared devices are very useful for atmospheric pollution monitoring, leak detection, laser surgery and other MIR applications. Nonetheless, nitrogen incorporation into these III-V semiconductor alloys during epitaxy growth is not easy. This thesis presents studies on nitrogen incorporation in GaAs, InAs, as well as InGaAs semiconductor alloys grown by metalorganic chemical vapor deposition (MOCVD). The effect of growth conditions to nitrogen incorporation as well as the effect of nitrogen to various properties in (In,Ga)As alloys are explored.