THICKENED ETCHING COATING LIQUID, AND METHOD FOR SELECTIVELY ETCHING SUNLIGHT POWER GENERATION ELEMENT SUBSTRATE FOR SOLAR CELL USING THE THICKENED ETCHING COATING LIQUID

摘要

A HIGH VISCOSITY ETCHANT AND A SELECTIVE ETCHING METHOD FOR PHOTOVOLTAIC ELEMENT SUBSTRATES OF SOLAR CELLS USING THE SAME A main subject of the present invention is to provide a high viscosity etchant EL and a selective etching method using the same which etches a photovoltaic element substrate to a set depth concretely and does not spread undesirably. The high viscosity etchant EL of the present invention comprises an etchant being an alkaline solution for etching a photovoltaic element substrate 12; a viscosity increasing additive derived from a plant for increasing a viscosity of the etchant EL. The selective etching method comprises applying the high viscosity etchant EL to a surface of the photovoltaic element substrate 12; reacting the high viscosity etchant EL and the photovoltaic element substrate 12 by heating them; washing the photovoltaic element substrate 12 with pure water.