Method of producing a semiconductor substrate product and etching liquid

A method for manufacturing a semiconductor substrate product comprising:

• providing an etching liquid containing water, a hydrofluoric acid compound and an organic solvent, and
• applying the etching liquid to a semiconductor substrate, the semiconductor substrate having at least two silicon layers and a silicon oxide layer, the two silicon layers containing a p-type impurity and a n-type impurity, respectively, the silicon layers and the silicon oxide layer being exposed or to be exposed so as to contact with the etching liquid, and thereby selectively etching the silicon oxide layer,
• wherein the composition of the etching liquid is selected such that the etching resistance of the silicon layers is enhanced and galvanic corrosion is inhibited, and
• wherein the organic solvent is represented by the following formula (O-1):
• R11—(—O—R13-)n-O—R12 (O-1)
• wherein R11 and R12 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atom(s),
• R13 represents a linear or branched alkylene group having 1 to 4 carbon atom(s), and
• n represents an integer of 0 or 1.