External Quantum Efficiency and Device Reflectance of CIGS PV for Terrestrial and Space Based Applications

External quantum efficiency (EQE) of copper indium gallium diselenide (CIGS) based solar cells with different antireflection coatings (ARC) has been evaluated under the solar irradiance of airmasses (AM) 0 and 1.5G. The simulations are performed in the wavelength range of 300 - 2500 nm to investigate the absorptance and reflectance features below and above the band gap of the absorber layer. Short circuit current density is increased the most for AM 0 and 1.5G using MgF2 ARCs. However, these ARCs also reduce reflectance below the band gap energy of CIGS which will lead to absorption in other component layers, device heating, and lower operating efficiency.