Fabrication and Identification of the Efficiency of a Si-Based Solar Cell

Mohammad Mahmuduzzaman Tawhid

doi:10.11648/j.ie.20180201.12

Abstract

This research represents the fabrication and characterization of a solar cell which is based on a thin p-type silicon (Si) wafer. Solar cells are the basic building blocks of Solar Panels or Modules. There are presently nine companies manufacturing solar modules in the country. Nowadays a large amount of electricity comes from solar cell. The total demand for solar cells in assembling solar modules of the nine companies are about 80-90MWp annually. Mainly, cost of solar cell depends on the Brand, type of crystal structure (Mono or Multi) and the shape or size of wafer. For the first time in the country, ‘Bangladesh Atomic Energy Commission (BAEC)’ has set up a laboratory to fabricate crystalline solar cells on a pilot basis. The method used to fabricate solar cells is the low-cost diffusion technique using POCl 3 gas source. Several solar cells of 150×150 mm 2 sizes and 200 micrometer thick are produced and characterized in the laboratory. A p-type silicon wafer is cleaned and textured to make its surface pyramid shape for absorbing more sunlight. The p-n junction used in Si-based solar cell is created after applying diffusion technique using Phosphorus-oxy-try chloride (POCl 3 ) within the silicon wafer and putting Aluminum (Al) paste on one side of the wafer. Perfectly texturing ensures the excellent pyramid height of the silicon wafers. The pyramid heights of raw, textured and doped wafers are 8233.2 A, 15222.5 A and 55654.1 A respectively. The pyramid surface shows the increasing light absorption by the solar cell that can lead to an increase in conversion efficiency of the device. The efficiency of the produced solar cell is 3.3%. The results have shown that some challenges and good opportunities in getting the high-efficient and cost effective solar cells. If the cost effective technology can be made familiar in Bangladesh then it will help in solving the power crisis in the country a great deal.

Highlights

The photovoltaic (PV) effect was first observed by Alexandre-Edmond Becquerel in 1839
The purpose of this research is to fabricate solar cell using texturing and diffusion processes with mono crystalline p-type silicon wafer which acts as a light absorber due to its shape of roughness to produce electricity
From the Dektak images, it can be found the comparison of the surfaces among the raw, textured and doped wafers and the sharpness of surfaces such as pyramid shapes were increasing gradually which improves the absorption efficiency in order to improve efficiency of solar cell

Summary

Introduction

The photovoltaic (PV) effect was first observed by Alexandre-Edmond Becquerel in 1839. The market-share of thin-film never reached more than 20 percent in the last two decades and has been declining in recent years to about 9 percent of worldwide photovoltaic production in 2013 [3]. In 2014, Harvard University researchers developed a new type of battery based on organic molecules called Quinone. It is found in plants and is economical in a sense that it can store sunlight energy for a couple of days [4]. Due to the de-creasing amount of renewable energy resources, the per watt cost of solar energy device has become more important in the last decade, and is definitely set to become economical in the coming years and grow as better technology in terms of both cost and applications [5]. In 2016, manufacturers in China and Taiwan met the majority of global PV module

Objectives

Results

Conclusion