[0120] As the rinse liquid in the rinse treatment performed after the alkali development, pure water is used, and a suitable amount of surfactant can also be added thereto for use. 

[0121] After the development treatment or the rinse treat› ment, a treatment of removing the developer or rinse liquid adhered to the pattern by a supercritical fluid can be per› formed. 

[0122] In a case where the pattern forming method and the method for forming a patterned mask of the present invention have a step of developing using a developer containing an organic solvent, as this developer (hereinafter, also referred to as an organic-based developer), a polar solvent or a hydro› carbon-based solvent such as a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, an amide› based solvent, or an ether-based solvent can be used. 

[0123] A plurality of solvents described above may be used in combination, or the solvent may be used in combination with a solvent other than the solvents described above or water. Here, in order to exhibit the effects of the present invention, the water content in the entirety of the developer is preferably less than 10% by mass, and the developer more preferably substantially does not contain water. 

[0124] That is, the amount of the organic solvent used with respect to the organic-based developer is preferably 90% by mass to 100% by mass and more preferably 95% by mass to 100% by mass, with respect to the total amount of developer. 

[0125] In particular, the organic-based developer is prefer› ably a developer containing at least one type of organic sol› vent selected from the group consisting of a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, amide-based solvent, and an ether-based solvent. 

[0126] The vapor pressure of the organic-based developer is preferably 5 kPa or lower, more preferably 3 kPa or lower, and particularly preferably 2 kPa or lower, at 20° C. When the vapor pressure of the organic-based developer is 5 kPa or lower, evaporation of the developer on the substrate or in a development cup is suppressed, the temperature evenness in the wafer surface is improved, and as a result, the dimensional evenness in the wafer surface is improved. 

[0127] A suitable amount of surfactant can be added to the organic-based developer, as necessary. 

[0128] The surfactant is not particularly limited, and for example, an ionic and nonionic fluorine-based surfactant and/ or a silicon-based surfactant can be used. Examples of the fluorine-based surfactant and/or the silicon-based surfactant include surfactants described in JP1987-36663A (JP-S62- 36663A), JP1986-226746A (JP-S61-226746A), JP1986- 226745A (JP-S61-226745A), JP! 987-170950A (JP-S62- 170950A), JP! 988-34540A (JP-S63-34540A), JP! 995- 230165A (JP-H07-230165A), JP! 996-62834A (JP-H08- 62834A), JP! 997-54432A (JP-H09-54432A), and JP! 997- 5988A (JP-H09-5988A), and the specifications of U.S. Pat. No. 5,405,720A, U.S. Pat. No. 5,360,692A, U.S. Pat. No. 5,529,881A, U.S. Pat. No. 5,296,330A, U.S. Pat. No. 5,436, 098A, U.S. Pat. No. 5,576,143A, U.S. Pat. No. 5,294,51 lA, and U.S. Pat. No. 5,824,451A, and a nonionic surfactant is preferable. The nonionic surfactant is not particularly limited, and a fluorine-based surfactant or a silicon-based surfactant is more preferably used. 

[0129] The amount of the surfactant used is typical 0.001 % by mass to 5% by mass, preferably 0.005% by mass to 2% by mass and more preferably 0.01 % by mass to 0.5% by mass, with respect to the total amount of developer. 

[0130] The organic-based developer may include a basic compound. Specific examples and preferable examples of the basic compound which can be included in the organic-based developer used in the present invention include the same as those of the basic compound which can be included in the active light-sensitive or radiation-sensitive resin composition described below. 

[0131] As the developing method, a method in which a substrate is dipped in a bath filled with a developer for a predetermined period of time ( dipping method), a method in which developing is performed by placing a developer on the substrate surface using surface tension and holding this sta› tionary for a predetermined period of time (puddle method), a method in which a developer is sprayed onto a substrate surface (spray method), or a method in which a substrate is rotated at a constant rate, and a developer discharge nozzle is then scanned across the substrate at a constant rate while a developer is discharged continuously on the substrate from the nozzle ( dynamic dispensing method) can be applied. 

[0132] In addition, after a step of developing using a devel› oper including an organic solvent, while replacing with another solvent, a step of stopping the development may be performed. 

[0133] In the pattern forming method and the method for forming a patterned mask of the present invention, a step of developing using a developer including an organic solvent ( an organic solvent development step) and a step of performing development using an alkali aqueous solution (alkali devel› oping step) may also be used in combination. Thus, a finer pattern can be formed. 

[0134] In the present invention, a portion having weak exposure intensity is removed in an organic solvent develop› ment step, and a portion having strong exposure intensity is also removed by performing the alkali development step. Since pattern formation is performed without dissolving only a region having intermediate exposure intensity by the mul› tiple development process performing development multiple times in this manner, a finer pattern than usual can be formed (the same mechanism as that in paragraph "0077" of JP2008- 292975A). 

[0135] Although the order of the alkali developing step and the organic solvent development step in the pattern forming method of the present invention is not particularly limited, it is more preferable that the alkali developing is performed before the organic solvent development step. 

[0136] A step of washing using a rinse liquid is preferably included after the step of developing using a developer including an organic solvent. 

[0137] The rinse liquid used in the rinsing step after the step of developing using a developer including an organic solvent is not particularly limited as long as it does not dissolve the resist pattern, and a solution including a general organic sol› vent can be used. As the rinse liquid, a rinse liquid containing at least one type of organic solvent selected from the group consisting of a hydrocarbon-based solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, an amide-based solvent, and an ether-based solvent is preferably used. 

[0138] Specific examples of the hydrocarbon-based sol› vent, the ketone-based solvent, the ester-based solvent, the alcohol-based solvent, the amide-based solvent, and the ether-based solvent include the same as those described for the developer including an organic solvent. 

