Cleaning Agent For Silicon Wafer

A cleaning agent for a silicon wafer, as claimed in claim 1, wherein the water-repellent compound comprises at least one selected from the group consisting of the following general formulas [1] and [2].

• (R1)aSi(CH3)bHcX4-a-b-c [1]
• [R2Si(CH3)2-dHd]eNH3-e [2]
• where:
• R1 mutually independently represents one of a monovalent organic group having hydrocarbon group with a carbon number of from 1 to 18 and a monovalent organic group having fluoroalkyl chain with a carbon number of from 1 to 8;
• R2 mutually independently represents one of a monovalent organic group having hydrocarbon group with a carbon number of from 1 to 18 and a monovalent organic group having fluoroalkyl chain with a carbon number of from 1 to 8;
• X mutually independently represents at least one group selected from the group consisting of halogen group, alkoxy group, acetoxy group, trifluoroacetoxy group, —OC(CH3)═CHCOCH3, —OC(CH3)═N—Si(CH3)3, —OC(CF3)═N—Si(CH3)3, —CO—NH—Si(CH3)3, alkylsulfonate group, perfluoroalkylsulfonate group, nitrile group and a monovalent organic group whose element to be bonded to Si element is nitrogen;
• a is an integer of from 1 to 3;
• each of b and c is an integer of from 0 to 2;
• the total of a, b and c is from 1 to 3;
• d is an integer of from 0 to 2;
• e is an integer of from 1 to 3.

A water-repellent cleaning liquid for providing water repellency, during a cleaning process for a silicon wafer having at its surface a finely uneven pattern, at least to a recessed portion of the uneven pattern, comprising:

• a water-repellent compound having a reactive moiety chemically bondable to Si element in the silicon wafer, and a hydrophobic group;
• and
• an organic solvent containing at least an alcoholic solvent and mixed with the water-repellent compound,
• wherein the water-repellent compound and the organic solvent are mixed.

A cleaning agent for a silicon wafer having at its surface a finely uneven pattern, comprising:

• a cleaning liquid A comprising a water-based solution;
• and
• a cleaning liquid B for providing a recessed portion of the uneven pattern with water repellency,
• wherein the cleaning liquid B comprises a water-repellent compound, an alcoholic solution, and one of water and an acidic aqueous solution, wherein the water-repellent compound has a hydrophobic group and a hydrolyzable moiety which can form a unit chemically bondable to Si element in the silicon wafer, wherein the alcoholic solution contains an alcohol solvent, and wherein the water-repellent compound is mixed into the cleaning liquid B in an amount of from 0.2 to 20 mass % relative to the total quantity of 100 mass % of the cleaning liquid B thereby being able to exhibit a capillary force of not larger than 2.1 MN/m2 on the assumption that water is retained in the recessed portion of the surface of the silicon wafer which surface is provided with water repellency by the cleaning liquid B.

A cleaning agent for a silicon wafer, as claimed in claim 10, wherein the water-repellent compound having the hydrophobic group and the hydrolyzable moiety which can form the unit chemically bondable to Si element in the silicon wafer comprises at least one selected from the group consisting of:

• CmH2m+1SiRsX3-s (m=1-18);
• and
• CnF2n+1CH2CH2SiRtY3-t (n=1-8)
• where:
• s and t are integers of from 0 to 2;
• R is one of hydrogen atom and a monovalent hydrocarbon group;
• and X and Y are hydrolyzable moieties.

A water-repellent cleaning liquid for providing water repellency, during a cleaning process for a silicon wafer having at its surface a finely uneven pattern, at least to a recessed portion of the uneven pattern, comprising:

• a water-repellent compound having a hydrophobic group and a hydrolyzable moiety which can form a unit chemically bondable to Si element in the silicon wafer;
• an alcoholic solution containing an alcoholic solvent;
• and
• one of water and an acidic aqueous solution,
• wherein the water-repellent compound, the alcoholic solution and one of water and the acidic aqueous solution are mixed, and wherein the water-repellent compound is mixed into the water-repellent cleaning liquid in an amount of from 0.2 to 20 mass % relative to the total quantity of 100 mass % of the water-repellent cleaning liquid.