> Is there a way to etch chrome oxide ? i tried gold etchant as > recommended by a memsnet user, but that didn't work. What do you mean with "gold etchant" ? I do not know which gold etchant you are using, i use a gold etchant from sigma aldrich, i do not remember the chemical composition, but it has a dark red color. Such gold etchant does not etch Cr at all... Best regards, Andrea