Growth flux ratio dependence of microwave devices in molecular beam epitaxy

The effects of beam equivalent pressure ratio P_As4/P _Ga on electrical and microwave performance of GaAs low-noise metal-semiconductor field-effect transistors grown by molecular beam epitaxy were demonstrated. From experimental results, superior performances were achieved at the minimum beam equivalent pressure ratio of 30 under arsenic-stabilized condition. The optimum noise figure and its associated gain were attributed to the higher quality of the molecular beam epitaxial material at optimal growth conditions. An explanation of the experimental results was also proposed.