Water-Repellent Protective Film, and Chemical Solution for Forming Protective Film

A liquid chemical for forming a water-repellent protective film, the liquid chemical being for forming a water-repellent protective film on a wafer having at its surface an uneven pattern and containing at least one kind of element selected from the group consisting of titanium, tungsten, aluminum, copper, tin, tantalum and ruthenium at surfaces of recessed portions of the uneven pattern,

• the water-repellent protective film being formed at least on the surfaces of the recessed portions subsequent to a step of cleaning the wafer and prior to a step of drying the wafer, the liquid chemical for forming a water-repellent protective film comprising:
• a water-repellent protective film forming agent represented by the general formula [1]
• wherein R1 represents a C1-C18 monovalent hydrocarbon group the hydrogen elements of which may partially or entirely be replaced with a fluorine element(s), R2 mutually independently represents a monovalent organic group having a C1-C18 hydrocarbon group the hydrogen elements of which may partially or entirely be replaced with a fluorine element(s), and “a” is an integer of from 0 to 2;
• and
• a solvent,
• wherein the solvent comprises an alcohol having a carbon number of 6 or less;
• water;
• or both of the alcohol and water,
• the water-repellent protective film forming agent is present in a concentration of 0.05 to 2 mass % relative to the total amount of 100 mass % of the liquid chemical for forming a water-repellent protective film,
• water is present in a concentration of 0 to 80 mass % relative to the total amount of 100 mass % of the solvent,
• the alcohol is present in a concentration of 0 to 80 mass % relative to the total amount of 100 mass % of the solvent, and
• the total concentration of the alcohol and water is 0.8 to 100 mass % relative to the total amount of 100 mass % of the solvent.