A METHOD OF CLEANING A SEMICONDUCTOR SUBSTRATE FOR A SOLAR CELL, AND A CORRESPONDING CLEANING SYSTEM

A method of cleaning a semiconductor substrate for a solar cell, the method comprising: providing a semiconductor substrate; pre-oxidising the substrate with a pre-oxidising solution; oxidising the substrate with an oxidising solution to form an oxide on the surface of the substrate; removing the oxide from the surface of the substrate with an oxide removing solution; wherein the pre-oxidising solution is configured to remove metal ions from the surface of the substrate prior to the formation of the oxide on the substrate's surface, wherein the pre-oxidising solution is an acid solution comprising hydrogen chloride, and no other acid forming component.