Effect of lanthanum substrates on the structural, optical and electrical properties of copper selenide thin films designed for 5G technologies

In this work, copper selenide thin films coated onto glass and transparent lanthanum substrates are studied. The (glass, La)/CuSe which prepared by the thermal evaporation technique under a vacuum pressure of 10−5 mbar structurally, morphologically, optically, dielectrically electrically characterized. Lanthanum improved crystallinity increasing crystallite size decreasing both microstrains defect density selenide. La redshifts energy band gap doubled dielectric constant values. addition, employing Drude–Lorentz approaches for optical conduction to fit provided information about effects on drift mobility, plasmon frequency, free carrier scattering times at femtosecond level. mobility increased frequency range is modified when used. Verifying impedance spectroscopy tests in microwave domain have shown ability La(gate)/CuSe/Ag (source) transistors performing as pass filters. These filters suitable 5G technologies. cutoff reached ~ 5.0 GHz notch 2.80 glass/La/CuSe/Ag highpass