Performance Enhanced Characterization of InGaP/InGaAs/Ge Triple-Junction Solar Cell Based on Down-Shifting and Antireflection Using Eu-Doped Silicate Phosphor Layer

摘要

In this study, the luminescent down-shifting, scattering and antireflection of Eu-doped silicate phosphor layer coating on the GaAs semiconductor substrate using spin-on film technique with different surface coverage of phosphor particles are characterized. The conversion efficiency enhanced 9.677% for a MOCVD grown middle-cell current limited InGaP/InGaAs/Ge triple-junction (3-J) solar cell coating with a down-shifting Eu-doped silicate phosphor layer on the top surface is demonstrated under one-sun AM1.5 G illumination. Optical reflective spectrum and photoluminescence of Eu-doped silicate phosphors layer with different deposition holding times (or surface coverage of phosphor particles) are measured and compared. Dark and photocurrent-voltage (Ⅰ-Ⅴ) and external quantum efficiency (EQE) response of the 3-J cell with and without Eu-doped silicate phosphors layer were also measured and characterized. The 3-J cell with 3 wt% Eu-doped silicate phosphor layer also demonstrated a 2.194% absolute gain in efficiency compared with a reference cell, due to the luminescent down-shifting, forward scattering, and antireflection of the Eu-doped silicate phosphor layer.