Antimony Surfactant Effect on Green Emission InGaN/GaN Multi Quantum Wells Grown by MOCVD

An improvement in the optical and structural properties of green emitting InGaN/GaN Multi Quantum Wells (MQWs) was obtained by using antimony (Sb) as a surfactant during InGaN growth. Keeping the growth conditions for InGaN constant, Sb was introduced during InGaN growth while varying the [Sb]/([In] + [Ga]) flow ratio from 0 to 0.16%. The analysis results suggest that using the optimum [Sb]/([In] + [Ga]) ratio (0.04%–0.1%) during InGaN growth greatly improves the optical and structural properties of the MQWs without incorporating much Sb into the growing film and that the emission wavelength is also maintained with a slight blue shift. Under the optimum conditions of 0.05% Sb addition, the PL intensity was increased by as much as 3.3 times compared to the sample without Sb addition. The root mean square (RMS) roughness was reduced from 2.2 nm to 1.9 nm and the pit density was decreased from 2.0 × 10¹⁰ cm⁻² to 1.2 × 10¹⁰ cm⁻² when the amount of Sb was increased from 0% to 0.05%.