Anti-Glare Coatings Based on Porous Silicon Structures

I. A. Iwe1, Email

E. A. Gosteva2

V. V. Starkov3

D. M. Sedlovets3

O. Mong4

1Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong

2National University of Science and Technology «MISiS», Moscow, 119991, Russia

3Institute of Microelectronics Technology and High Purity Materials, Russian Academy of Sciences, Chernogolovka

4Department of Mechanical Engineering, Federal Polytechnic, Nekede, Nigeria

Abstract

Modern photovoltaic cells use conductive oxides or dielectric materials as antireflective coatings. Today, solar systems are the fastest growing energy generation systems due to the environmental concerns and increasing demand for a clean and renewable energy source. Silicon solar cells have dominated the current market of photovoltaic solar cells, accounting for over 95 % in the market. This due to the abundance of raw materials (silicon), low cost, simple and cheap manufacturing technology. Despite its dominance, fabrication of silicon solar cells with a high conversion efficiency has been challenging due to high sunlight reflectance (over 35 %). Traditional techniques such as antireflection coating (ARC) and texturing have failed to provide a solution as they leave a large potential energy unused due to inefficient light harvesting in the near infrared spectrum. In this work, we Varied the shape, height and width of the silicon surface structure to control the optical resonance and guide more light to the PV surface by bouncing the light around inside the PV cell, keeping the light in the cell longer and consequently increasing the chances of colliding with electrons. The surface reflection has been drastically reduced to almost zero using gradient porous silicon technique.

Anti-Glare Coatings Based on Porous Silicon Structures