Abstract: In etching of a single crystal silicon substrate having a Si crystal plane ((100) plane, (110) plane, and (111) plane) as a main plane, an etching rate on the (110) plane cannot be sufficiently reduced, and there is room for improvement in an etching rate ratio between the (110) plane and the (111) plane. An object of the present invention is to provide a silicon etching solution having excellent crystal plane isotropy in silicon etching and having a high etching selectivity ratio of silicon to a silicon oxide film. The problem is solved by a silicon etching solution containing: an acid group-containing compound having at least one acid group selected from the group consisting of a carboxy group, a sulfonic acid group, a phosphoric acid group, and a phosphonic acid group, and having pKa of 3.5 or more and 13 or less; a quaternary ammonium hydroxide; an oxidizing agent; and water.

Abstract: An etching solution has a high etching selectivity of silicon with respect to silicon-germanium and having high stability over time at a treating temperature in surface processing in manufacturing various semiconductor devices, particularly in various silicon composite semiconductor devices containing silicon-germanium. The silicon etching solution contains a compound having at least one carboxy group and having all pKa of 3.5 or more and 13 or less, or a salt thereof; an organic alkali; and water.

Abstract: A silicon etching solution contains: a quaternary ammonium hydroxide represented by the following Formula (1): R11R12R13R14N+·OH? (1) (in the formula, R11, R12, R13, and R14 are each independently an aryl group, a benzyl group, or an alkyl group having 1 to 4 carbon atoms, and the alkyl group, the aryl group, or the benzyl group may have a hydroxy group); a quaternary ammonium salt represented by the following Formula (2) and having 11 to 20 carbon atoms in total: R21R22R23R24N+·X? (2) (in the formula, one of R21, R22, R23, and R24 is an alkyl group having 16 or less carbon atoms, which may have a substituent, each of the remaining three is an alkyl group having 1 or 2 carbon atoms, the alkyl group having 16 or less carbon atoms and the alkyl group having 1 or 2 carbon atoms may have a hydroxy group, and X is at least one selected from the group consisting of BF4, a fluorine atom, a chlorine atom, and a bromine atom); a polyhydroxy compound having 2 to 12 carbon atoms and having two or more hydroxy groups in

Abstract: [Problem to be solved] Provided is a method for processing a substrate having high etching selectivity of silicon with respect to silicon-germanium and further having a high selection ratio of silicon with respect to a silicon oxide film and/or a silicon nitride film in surface processing when manufacturing various types of silicon devices, particularly various types of silicon composite semiconductor devices containing silicon-germanium. [Solution] A method for processing a substrate includes: bringing an etching solution into contact with a substrate including a silicon film and a silicon-germanium film to perform etching; and selectively removing the silicon film, in which the etching solution contains an organic alkali and water and has a dissolved oxygen concentration of 0.20 ppm or less.

Abstract: A silicon etching solution including an aqueous alkaline solution containing a hypohalite ion in a range of 0.05 mmol/L or greater and 5 mmol/L or less and having a pH of 12.5 or greater at 24° C.

Abstract: A silicon etching liquid which is characterized by containing a quaternary ammonium hydroxide represented by formula (1), a quaternary ammonium salt represented by formula (2) and water, and which is also characterized in that the concentration of the quaternary ammonium salt represented by formula (2) is more than 1% by mass but not more than 50% by mass. (1): R1R2R3R4N+·OH? (In formula (1), R1, R2, R3 and R4 may be the same groups or different groups, and each represents an optionally substituted alkyl group, aryl group or a benzyl group.) (2): R5R6R7R8N+·X? (In formula (2), R5, R6, R7 and R8 may be the same groups or different groups, and each represents an optionally substituted alkyl group having from 1 to 16 carbon atoms; and X represents BF4, a fluorine atom, a chlorine atom or a bromine atom.

Abstract: A silicon etching liquid which contains a quaternary ammonium hydroxide represented by formula (1), a quaternary ammonium iodide represented by formula (2), and water. (1): R11R12R13R14N+·OH? (In formula (1), each of R11, R12, R13 and R14 independently represents an aryl group, a benzyl group or an alkyl group having from 1 to 16 carbon atoms; and the alkyl group, the aryl group or the benzyl group may have a hydroxyl group.) (2): R21R22R23R24N+·I? (In formula (2), R21, R22, R23 and R24 may be the same groups or different groups, and each represents an optionally substituted aryl group, benzyl group or alkyl group having from 1 to 10 carbon atoms.

Abstract: An object of the present invention is to provide an etching liquid having a high silicon etch selectivity with respect to silicon-germanium and a high long term stability at a processing temperature, in surface processing during the production of various semiconductor devices, especially various silicon composite semiconductor devices containing silicon-germanium, and the problem is solved by a silicon etching liquid containing an alkaline compound, an aldehyde compound, and water, the aldehyde compound being a water-soluble aromatic aldehyde.

Abstract: A silicon etching solution includes a mixed solution comprising a quaternary alkylammonium hydroxide and water and further comprises a compound represented by the following formula (1): R1O—(CmH2mO)n—R2 ??(1) wherein R1 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R2 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, m is an integer of 2 to 6, and n is 1 or 2.

Abstract: A silicon etching solution includes a mixed solution comprising a quaternary alkylammonium hydroxide and water and further comprises a compound represented by the following formula (1): R1O—(CmH2mO)n—R2??(1) wherein R1 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R2 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, m is an integer of 2 to 6, and n is 1 or 2.

Abstract: An etching solution contains a quaternary ammonium compound as a main component, by which an etching rate for silicon is improved, no adhered substances are formed on an etching surface during etching, and the etching rate does not decrease even after continuous use for a long time. The silicon etching solution contains a phenol compound represented by the following Formula (1), a quaternary ammonium compound, and water, and has a pH of 12.5 or more. wherein R1 is a hydrogen atom, a hydroxy group, an alkyl group, an alkoxy group, or an amino group. R2 is a hydrogen atom, a hydroxy group, an alkoxy group, or an amino group. R1 and R2 are not hydrogen atoms at the same time. When R1 is a hydrogen atom, R2 is not a hydroxy group. When R1 is an alkyl group or a hydroxy group, R2 is not a hydrogen atom.

Abstract: An isotropic silicon etching solution contains a quaternary ammonium hydroxide; water; and the at least one compound selected from the group consisting of compounds represented by the following Formulas (1) and (2), in which the following Conditions 1 and 2 are satisfied. R1O—(CmH2mO)n—R2 ??(1) In the formula, R1 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R2 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, m is an integer of 2 to 6, and n is 1 to 3. With the proviso that, R1 and R2 are not hydrogen atoms at the same time, and when m=2, a total number (n+C1+C2) of n, the number of carbon atoms (C1) of R1, and the number of carbon atoms (C2) of R2 is 5 or more. HO—(C2H4O)p—H ??(2) In the formula, p is an integer of 15 to 1,000. Condition 1: 0.2?etching rate ratio (R110/R100)?1 Condition 2: 0.

Abstract: A silicon etching solution includes a mixed solution comprising a quaternary alkylammonium hydroxide and water and further comprises a compound represented by the following formula (1): R1O—(CmH2mO)n—R2??(1) wherein R1 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R2 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, m is an integer of 2 to 6, and n is 1 or 2.

Abstract: In the method, a trione compound represented by the following formula (1) is (i) reduced by NaAlH2(OCH2CH2OCH3)2 and subsequently further reduced by a metal borohydride salt, or (ii) reduced by calcium borohydride, thereby producing an amide alcohol compound represented by the following formula (3) (wherein, R1 and R2 may be the same or different and each represents a hydrogen atom or a protecting group of an ureylene group; R4 represents an alkyl group, an aralkyl group, or an aryl group; and each of R5, R6, and R7 represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom).

Abstract: In the method, a trione compound represented by the following formula (1) is (i) reduced by NaAlH2(OCH2CH2OCH3)2 and subsequently further reduced by a metal borohydride salt, or (ii) reduced by calcium borohydride, thereby producing an amide alcohol compound represented by the following formula (3) (wherein, R1 and R2 may be the same or different and each represents a hydrogen atom or a protecting group of an ureylene group; R4 represents an alkyl group, an aralkyl group, or an aryl group; and each of R5, R6, and R7 represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom).