Arsine flow rate effect on the low growth rate epitaxial InGaAs layers

Effect of arsine (AsH$_3$) flow rate on epitaxially grown unintentionally doped and low-growth rate InGaAs layer by using metalorganic organic vapor phase epitaxy at growth temperature (640$^\circ$C) are investigated. While all other sources and parameters are kept constant during growth, the AsH$_3$ flow rate in InGaAs layer is increased from 20 to 120 sccm. The epitaxial grown InGaAs layers have been characterized by optical microscopy, X-ray diffraction, photoluminescence, and Hall effect. It is found that the mobility of carriers increases from 3780 to 7043 cm$^2$/Vs, sheet carrier density decreases from 7.74 $\cdot$ 10$^{11}$ to 4.01 $\cdot$ 10$^{11}$ cm$^{-2}$, PL intensity of emission increases from 1.1 to 8.6 V by increasing the AsH$_3$ flow rate from 20 to 40 scvm. Moreover, the same trend of improvement is observed on the crystalline quality of InGaAs layers with changing of AsH$_3$ flow rate. The changing of AsH$_3$ flow rate between 20 and 120 sccm is found to have strong effect on properties of epitaxial InGaAs alloys.