| 摘要 |
PROBLEM TO BE SOLVED: To provide a recycling system for a tetramethylammonium hydroxide (TMAH) developing solution, which system is rapid, cost effective and exact, and provide a method for the same. SOLUTION: The recycling system for the developing solution comprises regenerating the recovered developing solution by specifying the TMAH concentration of the TMAH developing solution by the absorption value of the prescribed wavelength by a spectrometer. Two or more (m) pieces of wavelengths are selected between the wavelengths 220 nm and 250 nm and Ym and the absorption value A1 of the wavelength 210 nm are measured from the absorption value Y1 of the recovered developing solution of the (m) wavelengths. From Y1 to Ym are inputted to n-th polynominal Y=C<SB>1</SB>X<SP>n</SP>+ to +C<SB>n-1</SB>X+C<SB>n</SB>to obtain the correlation between the wavelengths and the absorption (X is the wavelength, (n) is a positive integer, from C<SB>1</SB>to C<SB>n</SB>are correlation coefficients). The wavelength 210 nm is inputted to the correlation equation to obtain the absorption value Y<SB>210</SB>. A3 which is the absorption value of the TMAH concentration in the developing solution is calculated by a difference between A1 and Y<SB>210</SB>and A3 is inputted to the absorption calibration curve of the TMAH concentration at the wavelength 210 nm to obtain the corresponding TMAH concentration. The TMAH is added to the recovered developing solution based on the concentration. COPYRIGHT: (C)2004,JPO |
