Which of the following semiconductors are transparent partia

Which of the following semiconductors are transparent, partially transparent, and opaque for visible light (lambda = 0.4 - 0.7 mu m): Si, GaAs, GaP, and GaN? Electron mobility in Ge at 300K is 3900 cm^2/V-sec. Find the mean free time in scattering of electrons. Effective mass is m_n*=1.6 m_0. If we have a 0.1mW 1.5eV monochromatic light source (1cm^2 illumination spot) shining normal to a 0.5mm-thick GaAs wafer, doped Na = 1017 cm^-3, which is configured with a transparent conductive layer on the top and an A1 film on the backside. A IV bias applied between the top and the bottom, and the lifetime of electrons is 5 Times 10^-9 s. Plot with MATLAB what the steady-state electron and hole concentrations should look like between the surface and the backside. Assume that none of the radiation is reflected off the surface.

Solution

GaAs , GaN is opaque in nature

si is transparent in nature