Effects of growth conditions on optical quality and surface morphology of InGaAsBi

The effects of Bi flux and pressure of AsH₃ on Bi incorporation, surface morphology and optical properties of InGaAsBi grown by gas source molecular beam epitaxy are studied. It is found that using relatively low pressure of AsH₃ and high Bi flux can strengthen the effect on the incorporation of Bi and increase its content linearly with Bi flux until it nearly reaches a saturation value. The result from Rutherford backscattering spectroscopy (RBS) confirms that the Bi incorporation can increase up to 1.13%. By adjusting Bi and As flux, we could improve the surface morphology of InGaAsBi sample. Room temperature photoluminescence shows strong and broad light emission at energy levels much smaller than the InGaAs bandgap.