Spectral response and quantum efficiency evaluation of solar cells: a review

The performance of solar cells has been verified by current–voltage (I–V) characterization and spectral response measurements. These characteristics of solar cells are dependent on cell design, material, fabrication technique, junction depth, and/or optical coatings. Generally, I–V curves are given preference when measuring the performance of solar cells and less emphasis is given to spectral response, internal quantum efficiency (IQE), and external quantum efficiency (EQE) quantum. In this chapter, an attempt has been made to understand the concept of spectral response and its importance, along with the relation of IQE and EQE. Other than spectral response, there are many other factors, i.e., weathering, mishandling, aging, etc., that could contribute to the inefficiency of solar cells and this can be projected clearly by obtaining a solar cell's quantum efficiency as well as its spectral response. By studying the solar spectrum for each solar cell, ways to broaden the spectrum region to maximize the use of the spectrum could be found. A literature review is presented in this chapter to understand the whole concept of IQE and EQE and their effect on the performance of silicon-based solar cells. Many recent papers have been compiled and simplified in a compact way so that this can be a convenient reference to other researchers in this field. Also, various techniques have been discussed to increase the efficiency of solar cells, which are proposed by a number of authors in the chapter.