JP2005164396A - Washing liquid concentration measuring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correctly measure the concentration of a detergent in washing liquid and substance to be washed. <P>SOLUTION: This washing liquid concentration measuring apparatus measures each concentration of a plurality of solutes containing at least the detergent dissolved in a solvent and the substance to be washed. The apparatus has a concentration calculating part for calculating the concentration of each solute from the output of a temperature detector, the output of a detector of specific physical quantities and the output of a speed calculating part, and an output unit for outputting the conversion result of the concentration calculating part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a cleaning liquid concentration measuring apparatus suitable for use in a liquid crystal production process or the like.

In the liquid crystal production process, as described in Patent Document 1, a cleaning apparatus for cleaning a resist such as a phenol resin applied to the surface of a liquid crystal with a cleaning solution in which TMAH (tetramethylammonium hydroxide) as a cleaning agent is dissolved. Is used.
JP-A-11-216430

  In the cleaning apparatus as in Patent Document 1, it is preferable to recycle the cleaning liquid from the viewpoint of economy and environmental conservation. However, the cleaning liquid may contain a resist mixed with the course of use, or TMAH may react with carbon dioxide in the air. This produces carbonate and causes deterioration of the cleaning solution.

  Therefore, in the cleaning apparatus, when the cleaning liquid is recycled, it is necessary to remove the resist and carbonate that have been mixed into the cleaning liquid and to supplement the new TMAH to control the TMAH concentration constant. For this purpose, it is necessary to accurately measure the TMAH concentration and the resist concentration in the cleaning liquid and, if necessary, the carbonate concentration in real time.

  An object of the present invention is to accurately measure the concentration of a cleaning agent and a substance to be cleaned in a cleaning liquid.

  Another object of the present invention is to accurately measure the concentration of a cleaning agent, a substance to be cleaned, and a cleaning agent reactive substance in a cleaning liquid.

The invention of claim 1 is a cleaning liquid concentration measuring apparatus for measuring each concentration (D ₁ ... D _n ) of a plurality of (n) solutes including at least a cleaning agent and a substance to be cleaned dissolved in a solvent. An ultrasonic wave transmitter for transmitting ultrasonic waves to the solution, an ultrasonic wave receiver for receiving ultrasonic waves propagated in the solution to be measured, and the propagation velocity (V) from the propagation time and propagation distance of the ultrasonic waves. The propagation speed is independently influenced by the speed calculation unit for calculating, the temperature detector for detecting the temperature (T) of the solution to be measured, and the concentration of each solute and the temperature of the solution to be measured (n-1). a type of the specific physical properties amount _{(α 1 ... α n-1} ), the affected independently the temperature of the concentration and the measured solutions of each solute and (n-1) type of the specific physical properties amount (α ₁ ... α _n-1 ), a specific physical property detector for detecting the temperature of the solution to be measured (T), the specific physical property amount (α ₁ . _n-1 ), a function D ₁ = F ₁ (V, T, α ₁ ... α _n-1 ) ... showing the relationship between the ultrasonic wave propagation velocity (V) and the concentration of each solute (D ₁ ... D _n ). D _n = F _n (V, T, α ₁ ... Α _n-1 ) stored in advance, the output (T) of the temperature detector and the output (α ₁ ... Α of the specific physical property detector) _n-1 ) and the output (V) of the velocity calculation unit, a concentration calculation unit for calculating the concentration (D ₁ ... D _n ) of each solute based on the function, and an output device for outputting the calculation result of the concentration calculation unit It is made to have.

  According to a second aspect of the invention, in the first aspect of the invention, the plurality of solutes are a cleaning agent and a cleaning substance.

  According to a third aspect of the present invention, in the second aspect of the present invention, the cleaning agent is tetramethylammonium hydroxide, the substance to be cleaned is a resist, and the specific physical property amount is absorbance.

  According to a fourth aspect of the present invention, in the first aspect of the present invention, the plurality of solutes are a cleaning agent, a substance to be cleaned, and a cleaning agent reactive substance.

  According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the cleaning agent is tetramethylammonium hydroxide, the cleaning target material is a resist, the cleaning agent reactive material is carbonate, and the specific physical property amount is Absorbance and conductivity.

For each of various multi-component solutions containing at least a cleaning agent (for example, TMAH) and a cleaning target material (for example, resist) in a cleaning solution as a solution to be measured, and further including a cleaning agent reactant (for example, carbonate) as necessary. Solution temperature (T), specific physical properties (α ₁ ... Α _n-1 ) such as absorbance (A) or conductivity (σ), ultrasonic propagation velocity (V), and concentration of each solute ( D ₁ ... D _n) function showing the relationship between _{D 1 = F 1 (V,} T, α 1 ... α n-1) ... D n = F n (V, T, α 1 ... α n-1) is Predetermined and stored in the storage unit. Thus, the temperature detector and the specific physical property detector detect the temperature (T) and the specific physical property (α ₁ ... Α _n-1 ) of the solution to be measured, and the velocity calculation unit transmits the ultrasonic wave. By calculating (V) and substituting the detection results and the calculation results into the aforementioned function, the concentration (D ₁ ... D _n ) of each solute can be reliably and easily measured.

  1 is a schematic diagram showing a cleaning device, FIG. 2 is a block diagram showing a cleaning liquid concentration measuring device, 3 is a front view showing a sensor, FIG. 4 is a waveform diagram showing a state of ultrasonic wave transmission and reception, and FIG. 5 is a cleaning liquid concentration measurement. FIG. 6 is a flowchart showing the operation principle of the cleaning liquid concentration measuring device.

  As shown in FIG. 1, the cleaning apparatus 100 cleans a resist such as a phenol resin applied to the surface of the liquid crystal with a cleaning solution in which TMAH as a cleaning agent is dissolved. The cleaning device 100 discharges the cleaning liquid in the circulation tank 101 from the cleaning head 101A to the surface of the liquid crystal. The cleaning apparatus 100 includes a regeneration unit 110 and a supply unit 120. The regeneration unit 110 has a drain tank 111 that receives the cleaning liquid discharged from the circulation tank 101. The cleaning liquid in the drain tank 111 is sent to the regeneration tank 114 via the resist removal device 113 by the pump 112, and mixed into the cleaning liquid. The resist as the substance to be cleaned is removed by the resist removing device 113. The supply unit 120 includes a supply tank 121 that receives the cleaning liquid sent from the regeneration tank 114 by the pump 115, and supplies the cleaning liquid in the supply tank 121 to the circulation tank 101.

The regeneration unit 110 of the cleaning apparatus 100 includes a cleaning agent reaction in which the TMAH concentration D ₁ as a cleaning agent in the cleaning liquid of the regeneration tank 114, the resist concentration D ₂ as a cleaning target substance, and TMAH react with carbon dioxide in the air. A cleaning liquid concentration measuring device 10 for measuring a concentration D ₃ of carbonate as a substance is provided. In the supply unit 120, new TMAH (NEW TMAH) is supplemented to the cleaning liquid in the supply tank 121 according to the measurement result of the cleaning liquid concentration measuring apparatus 10, and the TMAH concentration in the supply tank 121 to the circulation tank 101 is controlled to be constant. The supply unit 120 includes a cleaning liquid concentration measuring device 10 </ _b > A similar to the cleaning liquid concentration measuring device 10 in order to monitor the cleaning liquid concentration (D ₁ , D ₂ , D ₃ ) of the circulation tank 101.

Hereinafter, the configuration of the cleaning liquid concentration measuring apparatus 10 will be described.
The cleaning liquid concentration measuring apparatus 10 measures the concentration of each solute in a multi-component solution formed by dissolving a plurality of (n) solutes, including at least TMAH and a resin as a solvent, and further including carbonate in this embodiment. Yes, it has a computing device 11 (see FIG. 2) and a sensor 12 (see FIG. 3), and the computing device 11 is additionally provided with a display 13.

The sensor 12 is used by being put into the solution 1 to be measured.
The sensor 12 includes an ultrasonic transmitter / receiver (vibrator) 14 that also serves as an ultrasonic transmitter and an ultrasonic receiver, and a reflector 15. The ultrasonic wave transmitted from the ultrasonic transducer 14 to the solution 1 to be measured propagates through the solution 1 to be measured, is reflected by the reflecting plate 15, and is received by the ultrasonic transducer 14.

  The sensor 12 includes a temperature detector 16 made of a thermistor, and detects the temperature (T) of the solution 1 to be measured.

Further, the sensor 12 is affected by the concentration of each solute dissolved in the solution 1 to be measured 1 and the temperature (T) of the solution to be measured (n−1) types that are independently affected by the propagation velocity (V). (N-1) types of specific physical properties (α ₁ ... α _n− ) which are specific physical properties (α ₁ ... Α _n−1 ) and are independently influenced by the concentration of each solute and the temperature of the solution to be measured. ₁ ) A specific physical property detector for detecting ₁ ) is provided. If the solution 1 to be measured is a solution in which, for example, three solutes are dissolved (for example, an aqueous solution of TMAH, resist and carbonate), the sensor 12 is an absorbance detector that detects two specific physical quantities, for example, absorbance A. 17A and a conductivity detector 17B for detecting conductivity σ.

  The computing device 11 includes a sing-around unit 18, a temperature measurement unit 19, an absorbance detector 20 </ b> A as an example of a specific physical property measurement unit, a conductivity measurement unit 20 </ b> B, an input / output unit 21, a CPU 22, a ROM 23, and a RAM 24.

The detected amount of the ultrasonic transducer 14 is transferred to the CPU 22 via the sing-around unit 18 and the input / output unit 21, and the ultrasonic propagation speed (V) is calculated by the CPU 22 as a speed calculation unit, and the calculated speed is calculated. Data (V) is stored in the RAM 24. The sing-around method repeats the transmission of an ultrasonic burst and receives the reflected wave again after τ ₀ seconds, and transmits the reflected wave after τ ₀ seconds to repeat the ultrasonic wave propagation speed. This is a method for measuring (V). In FIG. 4, A is a transmission wave, and B is a reception wave. If the time from an arbitrary transmission time point until (k + 1) transmissions is performed is t (see C in FIG. 4), and P = t / k obtained by calculation is data P, the propagation speed V is It is given by the formula.
V = 2L ₀ / (P−τ ₀ )

Here, L ₀ is the distance between the ultrasonic transducer 14 and the reflector 15. τ ₀ and L ₀ are initially set by the τ ₀ setting unit 25 and the L ₀ setting unit 26.

  The temperature data (T) of the solution 1 to be measured detected by the temperature detector 16 is stored in the RAM 24 through the temperature measurement unit 19, the A / D conversion unit 27, and the input / output unit 21.

  Absorbance data (A) of the solution 1 to be measured detected by the absorbance detector 17A is stored in the RAM 24 via the absorbance measurement unit 20A, the A / D conversion unit 28A, and the input / output unit 21.

  The conductivity data (σ) of the solution 1 to be measured detected by the conductivity detector 17B is stored in the RAM 24 through the conductivity measuring unit 20B, the A / D conversion unit 28B, and the input / output unit 21.

The ROM 23 of the arithmetic unit 11 constitutes a storage unit of the present invention, and includes the temperature (T) of the solution 1 to be measured, the specific physical property amount (α ₁ ... Α _n-1 ) and the ultrasonic wave propagation velocity (V). The following functions indicating the relationship with the concentration (D ₁ ... D _n ) of each solute are stored.

D ₁ = F ₁ (V, T, α ₁ ... Α _n-1 ) (1)
D _n = F _n (V, T, α ₁ ... Α _n−1 ) (2)

Hereinafter, the calculation procedure of the TMAH concentration D ₁ (D _{1 · 1} , D _{1 · 2} ), the resist concentration D ₂ , and the carbonate concentration D ₃ will be described.

(A) TMAH concentration D _{1 · 1} and resist concentration D ₂
When the solution 1 to be measured is formed by dissolving two solutes TMAH and a resist, and the absorbance A is selected as a specific physical property amount, the concentration D _{1 · 1 of} TMAH that does not consider the influence of carbonate in the cleaning solution The resist concentration D ₂ is as follows.

D _{1 · 1} = F ₁ (V, T, A) (3)
D ₂ = F ₂ (V, T, A) (4)

  The above function can be expressed by a multi-order polynomial. For example, if a multi-degree polynomial including unknown constants C (1) to C (44) is set for an aqueous solution having two components of TMAH and resist as solutes, for example, It becomes like this. Here, to what order the multi-order polynomial is used is determined by the required accuracy of concentration measurement.

D _{1 · 1} = C (29) * X ₁ + C (30) (5)
X ₁ = (B (1) + C (28) * (B (1) ² + B (2) * B (3)) ^1/2 ) / B (3)
B (1) = C (1) + C (2) * T + C (3) * T ² + C (4) * T ³ + C (5) * T ⁴ + V * (C (6) + C (7) * T + C (8 ) * T ² ) + A * (C (9) + C (10) * T + C (11) * T ² )
B (2) = C (12) + C (13) * T + C (14) * T ² + C (15) * T ³ + C (16) * T ⁴ + V * (C (17) + C (18) * T + C (19 ) * T ² ) + A * (C (20) + C (21) * T + C (22) * T ² )
B (3) = C (23) + C (24) * T + C (25) * T ² + C (26) * T ³ + C (27) * T ⁴
D ₂ = C (31) * Y ₁ + C (32) (6)
Y ₁ = (X ₁ * (C (33) + C (34) * T + C (35) * T ² ) + C (36) + C (37) * T + C (38) * T ² + V) / (X ₁ * (C (39) + C (40) * T + C (41) * T ² ) + C (42) + C (43) * T + C (44) * T ² )

The constants C (1) to C (44) of the multi-order polynomial are determined as follows. That is, in a solution containing two components of TMAH and resist, the TMAH concentration (D _{1 · 1} ) is 0 to 3.00%, the resist concentration (D ₂ ) is 0.00 to 0.50%, and the temperature (T) is 20 to 30 ° C. As shown in Table 1, the ultrasonic wave propagation velocity V and absorbance A in the solution are measured for each combination. The measurement of the temperature (T), speed (V), and absorbance (A) can be performed using the measuring apparatus 10 of the present invention as described later.

Prepare at least 44 combinations of D _{1 · 1} , D ₂ , T, V, A shown in Table 1, and assign the data to the equations (5) and (6) for each set to obtain a constant C (1 The constants C (1) to C (44) can be determined as shown in Table 2 by solving the 44-ary simultaneous equations having unknown numbers of) to C (44). This constant C (i) is stored in the ROM 23 of the arithmetic unit 11 by the ROM writer. The ROM writer calculates and verifies each constant C (i) from each D _{1 · 1} , D ₂ , T, V, A (D _{1 · 1} , D ₂ , Only when each C (i) (according to T, V, A) is appropriate, it is stored in the ROM 23.

(B) TMAH correction concentration D _{1 · 2} and carbonate concentration D ₃
For example, when carbonate is mixed in the solution 1 to be measured, the sound velocity changes, so it is necessary to correct the TMAH concentration D _{1 · 1} . The resist concentration D ₂ is not affected by the carbonate and does not affect the amount of physical properties other than the absorbance, so there is no need for correction. When the solution 1 to be measured is formed by dissolving three solutes TMAH, resist, and carbonate, and the conductivity σ is selected as a specific physical quantity, the concentration D _{1 · 2 of} TMAH and the concentration D of carbonate D ₃ is as follows.

D _{1 · 2} = F ₃ (D _{1 · 1} , T, σ) (7)
D ₃ = F ₄ (D _{1 · 1} , T, σ) (8)

  The above function can be expressed by a multi-order polynomial, and for an aqueous solution having three components of TMAH, resist and carbonate as solutes, a multi-order polynomial including unknown constants G (1) to G (44) is set. For example: Here, to what order the multi-order polynomial is used is determined by the required accuracy of concentration measurement.

D _{1 ・ 2} = G (29) * X ₂ + G (30) (9)
X ₂ = (H (1) + G (28) * (H (1) ² + H (2) * H (3)) ^1/2 ) / H (3)
H (1) = G (1) + G (2) * T + G (3) * T ² + G (4) * T ³ + G (5) * T ⁴ + V * (G (6) + G (7) * T + G (8 ) * T ² ) + σ * (G (9) + G (10) * T + G (11) * T ² )
H (2) = G (12) + G (13) * T + G (14) * T ² + G (15) * T ³ + G (16) * T ⁴ + V * (G (17) + G (18) * T + G (19 ) * T ² ) + σ * (G (20) + G (21) * T + G (22) * T ² )
H (3) = G (23) + G (24) * T + G (25) * T ² + G (26) * T ³ + G (27) * T ⁴
D ₃ = G (31) * Y ₂ + G (32) (10)
Y ₂ = (X ₂ * (G (33) + G (34) * T + G (35) * T ² ) + G (36) + G (37) * T + G (38) * T ² + V) / (X ₂ * (G (39) + G (40) * T + G (41) * T ² ) + G (42) + G (43) * T + G (44) * T ² )

The constants G (1) to G (44) of the multi-order polynomial are determined as follows. That is, in a solution containing three components of TMAH and resist carbonate as a solute, since the resist concentration (D ₂ ) has already been obtained by equation (6), the TMAH concentration (D _{1 · 2} ) and carbonate In order to obtain the concentration (D ₃ ), the TMAH concentration (D _{1 · 2} ) 0 to 3.00%, the carbonate concentration (D ₃ ) 0 to 9999 ppm, the resist concentration (D ₂ ) 0.00 to 0.50%, the temperature ( T) The ultrasonic propagation velocity V and conductivity σ are measured for a combination of 20 to 30 ° C. The temperature (T), speed (V), and conductivity (σ) can be measured using the measuring apparatus 10 of the present invention as will be described later.

Prepare at least 44 combinations of D _{1 · 2} , D ₃ , D _{1 · 1} , T, and σ, and substitute the data of each set into the equations (9) and (10) to obtain constants G (1) ˜ Each constant G (1) to G (44) can be determined by solving a 44-ary simultaneous equation with G (44) as an unknown. This constant G (i) is stored in the ROM 23 of the arithmetic unit 11 by the ROM writer. Note that the ROM writer calculates and verifies each constant G (i) from each D _{1 · 2} , D ₃ , D _{1 · 1} , T, σ, and only when each G (i) is appropriate, It is stored in the ROM 23 together with G (i).

Therefore, the CPU 22 as the concentration calculation unit of the present invention calculates the concentration of the solution (cleaning solution) in which the three solutes TMAH, the resist, and the carbonate are dissolved as follows. That is, the CPU 22 calculates the ultrasonic wave propagation speed (V) calculated based on the detection amount of the ultrasonic transducer 14, the temperature (T) detected by the temperature detector 16, and the absorbance detected by the absorbance detector 17 </ b> A ( By substituting each of A) into the above-described equations (1) and (2), specifically, for example, equations (5) and (6), TMAH concentration D _{1 · 1} and resist concentration D ₂ are calculated. (See FIG. 6A). Similarly, by substituting the temperature (T) and the conductivity (σ) detected by the conductivity detector 17B into the above-described formulas (9) and (10), for example, TMAH correction concentrations D _{1 and 2} and The carbonate concentration D ₃ is calculated (see FIG. 6B).

The arithmetic device 11 includes a function setting unit 29. The function setting unit 29 is for setting the operation of the arithmetic unit 11, and (1) a mode for measuring and displaying only the ultrasonic propagation velocity V, (2) a mode for measuring and displaying only the temperature T, and (3) a specific Physical properties (α ₁ ... Α _n−1 ) For example, a mode for measuring and displaying only the absorbance A and the conductivity σ, and (4) a mode for calculating and displaying the concentrations D ₁ , D ₂ , and D ₃ are set. The measurement result and the calculation result obtained by the setting of the function setting unit 29 are displayed on the display device 13 or taken out from the output unit 30 as digital output or analog output. The display 13 and the output unit 30 constitute an output device of the present invention, and these outputs can be used as cleaning agent (TMAH) concentration control information of the cleaning device 100 or the like.

Hereinafter, a procedure for measuring the concentration of an aqueous solution (cleaning solution) containing three components of TMAH, resist, and carbonate as a solute by the concentration measuring apparatus 10 will be described (see FIG. 5). The above-described τ ₀ and L ₀ are set by the τ ₀ setting unit 25 and the L ₀ setting unit 26 of the calculation device 11 and the function setting unit 29 is set to any measurement / calculation mode.

  (1) In the sound velocity calculation mode, the sound velocity processing subroutine is activated, and the ultrasonic wave propagation velocity (V) in the solution to be measured 1 (cleaning solution) is calculated and output as described above.

  (2) In the temperature measurement mode, the temperature processing subroutine operates, and the temperature (T) of the solution 1 to be measured is measured and output as described above.

  (3) In the absorbance measurement mode, the absorbance processing subroutine operates, and the absorbance (A) of the solution 1 to be measured is measured and output as described above.

  (4) In the conductivity measurement mode, the conductivity processing subroutine operates, and the conductivity (σ) of the solution 1 to be measured is measured and output as described above.

(5) In the concentration calculation mode, the data obtained in each of the subroutines (1) to (4) is used, and the TMAH concentration D ₁ (D ₁₎ is calculated from the function stored in the ROM 23 as described above. ₂ ) The resist concentration D ₂ and the carbonate concentration D ₃ are calculated and output.

In the present invention, the ultrasonic wave propagation velocity V, the temperature T of the cleaning liquid, the absorbance A, and the conductivity σ are substituted into the following formulas (11) to (13), respectively. It is also possible to calculate the concentration D _{1 of} TMAH, which is a solute, the concentration D _{2 of} resist, and the concentration D _{3 of} carbonate.

D ₁ = F ₁ (V, T, A, σ) (11)
D ₂ = F ₂ (V, T, A, σ) (12)
D ₃ = F ₃ (V, T, A, σ) (13)

  In the practice of the present invention, the cleaning agent is not limited to TMAH, and the substance to be cleaned is not limited to resin.

  As specific physical property amounts used in the practice of the present invention, the density, pH, refractive index of light, attenuation factor of radiation, use frequency of ultrasonic waves, third solute addition amount to the solution to be measured, etc. can be widely adopted.

  According to the present invention, the concentration of the cleaning agent and the substance to be cleaned in the cleaning liquid, and the concentration of the cleaning agent, the substance to be cleaned and the cleaning agent reaction substance can be accurately measured in real time, so that the liquid crystal production process, the semiconductor production process, etc. Widely applicable in industrial process.

FIG. 1 is a schematic view showing a cleaning apparatus. FIG. 2 is a block diagram showing a cleaning liquid concentration measuring apparatus. FIG. 3 is a front view showing the sensor. FIG. 4 is a waveform diagram showing an ultrasonic wave transmission / reception state. FIG. 5 is a flowchart showing the operation of the cleaning liquid concentration measuring apparatus. FIG. 6 is a diagram showing the calculation principle of the cleaning liquid concentration measuring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cleaning liquid density | concentration measuring apparatus 11 Arithmetic apparatus 13 Indicator 14 Ultrasonic wave transmitter / receiver 16 Temperature detector 17A Absorbance detector 17B Conductivity detector 22 CPU (speed calculating part, concentration calculating part)
23 ROM (storage unit)
30 Output section

Claims (5)

A cleaning liquid concentration measuring apparatus for measuring concentrations (D ₁ ... D _n ) of a plurality of (n) solutes including at least a cleaning agent and a substance to be cleaned dissolved in a solvent, and transmitting ultrasonic waves to the solution to be measured An ultrasonic transmitter, an ultrasonic receiver that receives the ultrasonic wave propagated in the solution to be measured, a velocity calculation unit that calculates the propagation velocity (V) from the propagation time and propagation distance of the ultrasonic wave, A temperature detector that detects the temperature (T) of the solution to be measured, and (n-1) types of specific physical properties (α) that are independently affected by the propagation speed depending on the concentration of each solute and the temperature of the solution to be measured. ₁ ... α _n-1 ) and (n-1) kinds of specific physical properties (α ₁ ... α _n-1 ) that are independently influenced by the concentration of each solute and the temperature of the solution to be measured a specific physical property quantity detector, the measured solution temperature (T), the specific physical properties amount _{(α 1 ... α n-1} ) and the ultrasonic Den Function showing the relationship between the speed (V) and the density (D ₁ ... D _n) of each solute _{D 1 = F 1 (V,} T, α 1 ... α n-1) ... D n = F n (V, T , Α ₁ ... Α _n−1 ), the output of the temperature detector (T), the output of the specific physical property detector (α ₁ ... Α _n−1 ), and the speed calculation unit Cleaning solution concentration measurement comprising a concentration calculation unit that calculates the concentration (D ₁ ... D _n ) of each solute based on the function from the output (V), and an output device that outputs the calculation result of the concentration calculation unit. apparatus.   The cleaning liquid concentration measuring apparatus according to claim 1, wherein the plurality of solutes are a cleaning agent and a substance to be cleaned. The cleaning agent is tetramethylammonium hydroxide, the substance to be cleaned is a resist,
The cleaning liquid concentration measurement apparatus according to claim 2, wherein the specific physical property amount is absorbance.   The cleaning liquid concentration measuring apparatus according to claim 1, wherein the plurality of solutes are a cleaning agent, a substance to be cleaned, and a cleaning agent reactive substance. The cleaning agent is tetramethylammonium hydroxide, the cleaning material is a resist, and the cleaning material is a carbonate;
The cleaning liquid concentration measuring apparatus according to claim 4, wherein the specific physical property amounts are absorbance and conductivity.

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