Ultrathin single-crystalline silicon solar cells for mechanically flexible and optimal surface morphology designs

Abstract

Recently, the evolution of photovoltaic cells in together with flexible electronics rapidly grows up so as to satisfy the flexibility and elasticity needs. Therefore, it will be a breakthrough impact if it is able to develop flexible single-crystalline photovoltaic cells which are fabricated with traditional procedure and provide highly electrical properties as well. This study aims to fabricate the flexible solar photovoltaic device with practical and reproducible method. Generally, the flexible solar photovoltaic is manufactured on the 30μm-thickness single-crystalline silicon chip by chemical etching process. Versatile design on the flexible device can enhance light trapping effect. The surface texturization and antireflection layer deposition successfully minimize the reflectivity losses from the incident light. In addition, the developed devices under concave bending morphology demonstrates better operating performance than convex and flat configurations. As to the concave bending type, the significant improvement of power conversion efficiency (129% better than flat type, and 161% better than convex type) is observed from a large device current, which is related to the contribution of light trapping enhancement. In combination of all optimal conditions, the flexible device exhibits conversion efficiency up to 13.8%. The development of novel flexible solar photovoltaics with the excellent mechanical flexibility, low silicon material consumption and low fabrication cost demonstrates the potential capability for future solar cells.