By Guy Beaucarne, Head of the Solar Cell Technology Group, IMEC; Patrick Choulat, Development Engineer in Photovoltaics, IMEC; B.T Chan, Process Development Engineer, IMEC; Harold Dekkers, Process Engineer in Photovoltaics, IMEC; Joachim John, Industrial Solar Cells Team Leader, IMEC; Jozef Poortmans, Department Director Solar & Organic, IMEC
Si etch processes are vital steps in Si solar cell manufacturing. They are used for saw damage removal, surface texturing and parasitic junction removal. The next generation of Si solar cells, featuring thinner wafers and passivated rear surface, will pose more stringent demands on those steps. Surface decoupling (achieving different surface treatments on the front and the rear) has to be achieved while minimizing Si consumption. Plasma texturing is an emerging technique that appears very promising in that respect, as efficiencies as high as 17.4 % have been achieved on screenprinted multicrystalline Si solar cells incorporating this process.