Patent ID: 9159572
Filing Date: 2015-10-13
Classification: H01L

Abstract:
1. A method of producing a semiconductor substrate product, the method comprising: a step of preparing an aqueous solution containing 7% by mass or more and 15% by mass or less of a quaternary alkyl ammonium hydroxide; a step of preparing a semiconductor substrate having a silicon film comprising a polycrystalline silicon film or an amorphous silicon film; a step of heating the aqueous solution at 80° C. or higher and applying the resultant aqueous solution onto the semiconductor substrate to etch at least a part of the silicon film; a step of forming a multilayer film structure including a silicon film, and forming a concave-convex in the semiconductor substrate, in the step of preparing the semiconductor substrate, then a step of forming a conductive film at least on the upper surface of a concave-convex surface and on the wall surface of a concave portion; a step of applying an embedded film onto the conductive film to fill the concave portion with the embedded film; and a step of removing a part of the conductive film portion applied on the upper surface and the embedded film to expose the silicon film of the semiconductor substrate, and thereafter, a step of applying the aqueous solution onto the semiconductor substrate to remove the exposed silicon film and the embedded film while leaving the conductive film on the wall surface of the concave portion, as the etching step of the silicon film, wherein the semiconductor substrate comprises a Ti compound, and a portion of the silicon film is etched selectively to the Ti compound.