Design and optimization of ultrathin crystalline silicon solar cells using an efficient back reflector

S Saravanan,R S Dubey,S Kalainathan,M A More,D K Gautam

doi:10.1063/1.4921944

Abstract

Thin film solar cells are cheaper but having low absorption in longer wavelength and hence, an effective light trapping mechanism is essential. In this work, we proposed an ultrathin crystalline silicon solar cell which showed extraordinary performance due to enhanced light absorption in visible and infrared part of solar spectrum. Various designing parameters such as number of distributed Bragg reflector (DBR) pairs, anti-reflection layer thickness, grating thickness, active layer thickness, grating duty cycle and period were optimized for the optimal performance of solar cell. An ultrathin silicon solar cell with 40 nm active layer could produce an enhancement in cell efficiency ∼15 % and current density ∼23 mA/cm2. This design approach would be useful for the realization of new generation of solar cells with reduced active layer thickness.

Highlights

Today, the cost reduction of silicon solar cells is a serious issue to scientific community
Surface plasmon is nothing than gathering of electrons at the surface of metal which makes a path of propagation along it and surface plasmonic energy is concentrated at the tip of metal nanoparticels/nanogratings
Due to this unique nature, surface plasmon resonance have found its application in solar cells which contribute to the enhancement of light absorption if the metal nanostructure is placed adjacent to active region of solar cell

Summary

Introduction

The cost reduction of silicon solar cells is a serious issue to scientific community. Thin film technology has been employed and demonstrated the low cost silicon solar cells whereas such thin film silicon solar cells are having poor absorption in longer wavelength region due to indirect band gap of silicon material To overcome this problem several design schemes have been reported in literatures such as textured grating, dielectric grating, metal nanoparticles or nanograting, alternate arrangement of metal/dielectric grating etc.[1,2,3,4,5] These ideas are found to be effective because of scattering the incident light and coupling it into the fundamental material. Surface plasmon is nothing than gathering of electrons at the surface of metal which makes a path of propagation along it and surface plasmonic energy is concentrated at the tip of metal nanoparticels/nanogratings Due to this unique nature, surface plasmon resonance have found its application in solar cells which contribute to the enhancement of light absorption if the metal nanostructure is placed adjacent to active region of solar cell

Methods

Results

Conclusion