By Ralf Lüdemann, Managing Director, SolarWorld; Ute Mareck, Deutsche Cell, SolarWorld; Michael Eberspächer, Head of Quality Assurance, SolarWorld
The emitter or p-n junction is the core of crystalline silicon solar cells. The vast majority of silicon cells are produced using a simple process of high temperature diffusion of dopants into the crystal lattice. This paper takes a closer look at the characteristics of this diffusion and possible variations in the process, and asks whether this step can lead to optimal emitters or whether emitters should be made with different processes in order to obtain the highest possible efficiency.