Category: Third Generation Photovoltaics

Quasi-Fermi Levels E.1 Introduction

The concept of a fermi level was introduced in Chap. 4 to describe the energy distribution of electrons and holes in thermal equilibrium. In non-equilibrium, quasi-fermi levels or imrefs provide a useful tool for semiconductor device analysis as outlined below. Formally, they correspond to the electrochemical potentials of non-equilibrium thermodynamics. E.2 Thermal Equilibrium A system […]

C.4 Approximate Expressions

Considerable effort has been invested in deriving approximate expressions for Fermi-Dirac integrals as reviewed elsewhere (Blakemore 1982). One compact approximation for negative arguments is based on the following expression: 2-(j+1) <> C± <>±(1II±(0)-1) will give the best results for negative arguments, where the value on the right is ensures that the expression gives the correct […]

Physical Constants

Symbol Definition V alue* q electronic charge 1.602176462(63) x 10-19C m0 electron rest mass 9.10938188(72) x 10-28g 9.10938188(72) x 10-31 kg П circle circumference to diameter (calculable) 3.14159265358979… c velocity of light in vacuum (exact value) 2.99792458 x 1010 cm/s 2.99792458 x 108 m/s £o permittivity of vacuum (exact value) 8.854187817.. . x 10-14 F/cm […]


From the analysis of this book, it appears that there are sufficient options for improving the performance of solar photovoltaic cells beyond the single junction limits, that greatly improved performance, at some stage in the future, is very likely. The tandem cell approach of Chap. 5 already demonstrates that such enhanced performance is feasible. Cell […]