Photovoltaic technologies have advanced significantly in recent decades, with perovskite solar cells (PSCs) achieving efficiencies over 25%. The tin-based environmentally benign perovskite material CH3NH3SnI3 or MASnI3 has excellent optical absorption, high carrier mobility, and a small band gap of 1.3 eV, making it a suitable absorber layer in solar cells. The careful selection of suitable charge transport layers is crucial because there might be appeared conduction band offset (CBO) between the Electron Transport Layer (ETL) and the absorber, which might affect the photovoltaic performance. To address the CBO issue, this study uses an ETL called indium gallium zinc oxide (IGZO). SCAPS-1D has been utilized in this numerical analysis to investigate the PSC structures consisting of IGZO (ETL)/MASnI3 (absorber)/Cu2O (HTL). Furthermore, the absorber layer thickness, absorber layer doping concentration, ETL and HTL doping concentrations, and temperature have also been investigated. The outstanding optimized results have been achieved from the proposed device with efficiency 29.73%, VOC = 1.03 V, JSC = 32.90 mA/cm2, and FF = 87.66%. The high PCE of this device provides a new opportunity to generate clean energy, and if manufactured correctly and properly fabricated, it may start a new direction in the photovoltaic industry.