JP2021008001A - Polishing liquid supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technical means for obtaining a higher quality polishing liquid. A blending flow path 40 is arranged immediately before a liquid delivery port 79 leading to a CMP polishing apparatus 8. The compounding flow path 40 communicates with the flow paths 10DIW, 10CHM, 10SLR, and 10H2O2. The mixing flow path 40 is provided with a plurality of mixing units 50CHM, 50SLR, and 50H2O2 having two inlets F1 and F2 and one outlet F3 connected in a plurality of stages. Therefore, it is possible to accurately perform stepwise preparation of three or more kinds of liquids, such as blending chemicals in ultrapure water → further blending slurry → further blending hydrogen peroxide solution. [Selection diagram] Fig. 1

Description

The present invention relates to a polishing liquid supply device that supplies a polishing liquid obtained by diluting a slurry to a polishing device of CMP (Chemical Mechanical Polishing).

In the semiconductor manufacturing process, there is a step called polishing, in which the etched wafer 88 is mechanically and chemically polished. FIG. 9 is a diagram showing a schematic configuration of the CMP system used in this step. As shown in FIG. 9, the CMP system includes a polishing device 8 and a polishing liquid supply device 29. The wafer 88 to be polished is adhered to the sticking board 82 on the lower surface of the head 81 of the polishing device 8. The head 81 presses the wafer 88 against the polishing pad 84 on the surface plate 83. In the tank 91 of the polishing liquid supply device 29, a polishing liquid obtained by diluting the slurry with ultrapure water or a chemical is stored. When the polishing liquid in the tank 91 of the polishing liquid supply device 29 is sucked out by the pump 92 and the head 81 and the platen 83 are rotated while dropping the polishing liquid from the tip of the nozzle 85 onto the polishing pad 84, the wafer 88 causes the polishing pad 84. The surface of the wafer 88 is polished by the mechanical action of sliding on the polishing pad 84 while being pressed against the polishing pad 84 and the chemical reaction action of the wafer 88 coming into contact with the slurry in the polishing agent. For details of the configuration of the CMP system 1, refer to Patent Document 1.

It is known that the polishing shape of the wafer 88 in the CMP system depends on the rotation speed of the polishing pad 84 and the supply performance of the polishing liquid. In order to improve the polishing shape of the wafer 88, it is indispensable to keep the rotation speed of the polishing pad 84 and the supply amount of the polishing liquid per unit time constant. Generally, the amount of polishing removed increases in proportion to the relative speed between the wafer 88 and the polishing pad 84 and the processing pressure.

Japanese Unexamined Patent Publication No. 2017-13196

The CMP polishing liquid is obtained by mixing a slurry stock solution with a plurality of types of liquids such as a chemical substance and a hydrogen peroxide solution. When these multiple types of liquids are mixed step by step, the chemicals are first diluted with ultrapure water, then the slurry stock solution is prepared, and then the hydrogen peroxide solution is prepared. , A higher quality polishing solution. However, the conventional CMP device has a configuration in which a stirring device is installed in the tank of the polishing liquid supply device, the slurry stock solution, the chemical, and the hydrogen peroxide solution are stored in the mixing tank, and the mixture is stirred and mixed by the stirring device. Therefore, it was not suitable for stepwise preparation of multiple types of liquids.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a technical means for obtaining a higher quality polishing liquid.

In order to solve the above problems, the present invention is a polishing liquid supply device that supplies a polishing liquid to a CMP polishing device, and a plurality of liquids that transfer the slurry and a plurality of liquids including other liquids to be mixed with the slurry. A blending flow path arranged corresponding to a liquid transfer flow path and a liquid inlet / outlet leading to the CMP polishing apparatus, which communicates with the plurality of liquid transfer flow paths and mixes the plurality of liquids. A compounding flow path for supplying the polishing liquid to the CMP polishing apparatus is provided, and a plurality of mixing units having two inlets and one outlet are connected to the compounding flow path in a plurality of stages. Provided is a polishing liquid supply apparatus characterized in that a thing is provided.

In this polishing liquid supply device, the plurality of mixing units include a first mixing unit, a second mixing unit, and a third mixing unit, and one inlet of the first mixing unit is pure water. The liquid transfer flow path and the other inflow port are connected to the chemical liquid transfer flow path, and the outflow port is connected to one inflow port of the second mixing unit, and the other flow path of the second mixing unit is connected. The inlet is connected to the liquid transfer flow path of the slurry, and the outlet is connected to one inlet of the third mixing unit, and one inlet of the third mixing unit is the liquid transfer of hydrogen peroxide solution. The flow path and the outlet may be connected to the outlet of the liquid leading to the CMP polishing device, respectively.

In the present invention, the mixing flow path is provided with a plurality of mixing units having two inlets and one outlet connected in a plurality of stages. Therefore, it is possible to accurately perform stepwise preparation of three or more kinds of liquids, such as blending chemicals in ultrapure water → further blending slurry → further blending hydrogen peroxide solution.

It is a figure which shows the whole structure of the CMP system 1 including the polishing liquid supply device 2 which is 1st Embodiment of this invention. It is a figure which shows the detail of the structure of the drum 11 of FIG. It is a figure which shows the detail of the structure of the mixing unit 50 of FIG. It is a figure which shows the detail of the structure of the mixing unit 50 of FIG. It is a figure which shows the control of the drum 11 of the mixing unit 50 of FIG. It is a figure for demonstrating the action which concerns the stirring and blending of the mixing unit 50 of FIG. It is a figure which shows the whole structure of the CMP system 1 including the polishing liquid supply device 2 which is 2nd Embodiment of this invention. It is a figure which shows the detail of the structure of the pressure tank of the polishing liquid supply device 2 which is a modification of this invention. It is a figure which shows the schematic structure of the conventional CMP system.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
FIG. 1 is a diagram showing an overall configuration of a CMP system 1 including a polishing liquid supply device 2 according to a first embodiment of the present invention. The solid line connecting the elements in FIG. 1 indicates the pipe, and the arrow on the solid line indicates the traveling direction of the liquid in the pipe. The CMP system 1 is used in the polishing process of the semiconductor manufacturing process. The CMP system 1 includes a CMP polishing device 8 and a polishing liquid supply device 2. The liquid inlet 89 of the CMP polishing apparatus 8 is connected to the liquid inlet 79 of the polishing liquid supply apparatus 2. The CMP polishing apparatus 8 polishes the wafer 88 to be polished. The polishing liquid supply device 2 supplies the polishing liquid to the CMP polishing device 8.

The polishing liquid is a liquid prepared by mixing slurry, ultrapure water, chemicals, and hydrogen peroxide solution in a predetermined ratio. Here, there are various types of slurries such as a slurry containing an abrasive and the like, an alkaline slurry containing SiO ₂ , a neutral slurry containing CeO _2, and an acidic slurry containing Al ₂ O ₃ . There are various types of chemicals such as silica, mellow acid, and citric acid. The active ingredient of the slurry or chemical may be determined according to the wafer 88 to be polished, the polishing shape, and the like.

The configuration of the CMP polishing apparatus 8 is substantially the same as the configuration of the polishing apparatus 8 shown in FIG. The CMP polishing apparatus 8 is provided with an operator for setting the target values of the flow rate and the concentration at the flow rate detection points and the concentration detection points before and after the mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 of the polishing liquid supply device 2. There is. When the target value of the flow rate or the concentration is set in the CMP polishing device 8, the CMP polishing device 8 supplies the polishing liquid supply device 2 with a setting signal indicating the flow rate or the concentration after the setting.

The polishing liquid supply device 2 includes a PLC (Programmable Logic Controller) 70, an ultra-pure water inlet 29 connected to an external ultra-pure water supply source, a plurality of drums 11 _CHM in which chemicals are stored, and the weight of the drum 11 _CHM . load cell _{12 CHM} for detecting a pressure sensor _{13 CHM} for detecting the pressure in the drum _{11 CHM,} a plurality of drums _{11 SLR} slurry is stored, a load cell _{12 SLR} for detecting the weight of the drum _{11 SLR,} the drum _{11 SLR} a pressure sensor the pressure sensor _{13 SLR} for detecting the pressure in, the hydrogen peroxide solution to detect the pressure in the load cell _{12 H2 O2,} drum _{11 H2 O2} for detecting the weight of a plurality of drums _{11 H2 O2,} drum _{11 H2 O2} which is stored 13 _H2O2 , liquid transfer flow path 10 _DIW to which ultrapure water is transferred, liquid transfer flow path 10 _CHM to which chemicals are transferred, liquid transfer flow path 10 _SLR to which slurry is transferred, liquid to which hydrogen peroxide solution is transferred. It has a transfer flow path 10 _H2O2 and a mixing flow path 40 in which four kinds of liquids of ultrapure water, chemicals, slurry, and hydrogen peroxide solution are mixed.

The mixing flow path 40 is arranged immediately before the liquid delivery port 79 leading to the CMP polishing apparatus 8. The compounding flow path 40 communicates with the flow paths 10 _DIW , 10 _CHM , 10 _SLR , and 10 _H2O2 . The mixing flow path 40 includes flow controllers 15 _CHM , 15 _SLR , and 15 _H2O2 , flow rate sensors 61 _CHM , 63 _CHM , 61 _SLR , 63 _SLR , 61 _H2O2 , and 63 _H2O2 , and concentration sensors 64 _CHM , 64 _SLR , and 64 _H2O2 is provided.

The flow controller 15 _CHM is a unit in which the flow rate sensor 62 _CHM and the flow rate adjusting valve 26 _CHM are integrated. The flow controller 15 _SLR is a unit in which the flow rate sensor 62 _SLR and the flow rate adjusting valve 26 _SLR are integrated. The flow controller 15 _H2O2 is a unit in which the flow rate sensor 62 _H2O2 and the flow rate adjusting valve 26 _H2O2 are integrated. The flow controllers 15 _CHM , 15 _SLR , and 15 _H2O2 serve as flow rate adjusting means for adjusting the flow rate of the liquid from the liquid transfer flow paths 10 _CHM , 10 _SLR , and 10 _H2O2 to the blending flow path 40.

A low pressure valve 21 (precision regulator) is provided in the flow path 10 _DIW . By the action of the low pressure valve 21, the flow rate of ultrapure water in the flow path 10 _DIW is kept constant (for example, 1 liter / minute).

The flow path 10 _CHM is provided with a gas pressurizing unit 14 _CHM . The flow path 10 _SLR is provided with a gas pressurizing unit 14 _SLR . The flow path 10 _H2O2 is provided with a gas pressurizing unit 14 _H2O2 .

Gas pressure portion _{14 CHM,} 14 _{SLR, 14 H2O2} is drum _{11 CHM,} 11 _{SLR, 11 H2O2} to send the nitrogen is an inert gas, the drum _{11 CHM,} 11 _{SLR, 11} the passage 10 the liquid in the _{H2O2 Extrude to CHM} , 10 _SLR , 10 _H2O2 .

As shown in FIG. 2, the drums 11 _CHM , 11 _SLR , and 11 _H2O2 have a top plate 31, a bottom plate 32, and a side plate 33 interposed between them. The inside of the drums 11 _CHM , 11 _SLR , and 11 _H2O2 is airtight. A drum support unit, a SUS (Steel Use Stainless) plate 311, a PVC (Polyvinyl Chloride) plate 312, a PVC plate 321 and a SUS plate 322, are provided on the top plate 31 and below the bottom plate 32. The first plate, the SUS plate 311 and the PVC plate 312, are arranged on the top plate 31, and the second plate, the PVC plate 321 and the SUS plate 322, are arranged under the bottom plate 32. .. Load cells 12 _CHM , 12 _SLR , and 12 _H2O2 are arranged under the SUN plate 322.

The SUS plate 312 and the PVC plate 311 hold down the top plate 31 from above, and the PVC plate 321 and the SUS plate 322 hold down the bottom plate 32 from below to prevent outbursts due to pressurization in the drums 11 _CHM , 11 _SLR , and 11 _H2O2 . It plays a role. An air cylinder 38 is provided on the drums 11 _CHM , 11 _SLR , and 11 _H2O2 . The air cylinder 38 allows the SUS plate 312 and the PVC plate 311 to be lifted up and separated from the top plate 31.

A first tube is connected to the tip of the pipe from the flow path 10 _CHM , 10 _SLR , 10 _H2O2 to the drum 11 _CHM , 11 _SLR , 11 _H2O2 . A second tube is connected to the tip of the pipe from the gas pressurizing section 14 _CHM , 14 _SLR , 14 _H2O2 to the drum 11 _CHM , 11 _SLR , 11 _H2O2 . The first tube and the second tube passes through the drum _{11 CHM,} 11 _{SLR, 11} opening in the top plate 31 of _{H2 O2,} are drawn into the drum _{11 CHM,} 11 _{SLR, 11} in _{H2 O2.} The lower end of the first tube in the drum _{11 CHM,} 11 _{SLR, 11} in _H2O2 is in the bottom of the drum _{11 CHM,} 11 _{SLR, 11 H2O2,} the lower end of the second tube, the drum _{11 CHM,} 11 _{SLR, 11 H2O2} It is on the surface of the liquid inside.

The first tube of the drum _{11 CHM, 11 SLR, 11 H2O2} , and a valve for regulating the drum _{11 CHM, 11 SLR, 11 H2O2} from the flow path _{10 CHM, 10 SLR, 10} delivery of liquid to the _H2O2 provided There is. The second tube is provided with a valve that regulates the delivery of nitrogen from the gas pressurizing portions 14 _CHM , 14 _SLR , 14 _H2O2 to the drums 11 _CHM , 11 _SLR , 11 _H2O2 .

The valve of the first tube connected to the flow paths 10 _CHM , 10 _SLR , and 10 _H2O2 in the drums 11 _CHM , 11 _SLR , and 11 _H2O2 was closed, and the valve was connected to the gas pressurizing portions 14 _CHM , 14 _SLR , and 14 _H2O2 . When the valve of the tube 2 is opened and nitrogen is sent out from the gas pressurizing parts 14 _CHM , 14 _SLR , and 14 _H2O2 , the nitrogen enters the drums 11 _CHM , 11 _SLR , 11 _H2O2 , and the drums 11 _CHM , 11 The pressure in _SLR , 11 _H2O2 increases. After the pressure in the drums 11 _CHM , 11 _SLR , and 11 _H2O2 increased, the valve of the second tube connected to the gas pressurizing parts 14 _CHM , 14 _SLR , and 14 _H2O2 was closed, and the flow path 10 _CHM , 10 _SLR. and opens the valve of the first tube that led to _{10 H2O2,} is extruded into the drum _{11 CHM,} 11 _{SLR, 11} liquid in the _H2O2 is the channel _{10 CHM, 10 SLR, 10 H2O2} .

The piping of the flow path 10 _DIW is connected to the inflow port F1 of the mixing unit 50 _CHM . The piping of the flow path 10 _CHM is connected to the inflow port F2 of the mixing unit 50 _CHM . The piping of the flow path 10 _SLR is connected to the inflow port F2 of the mixing unit 50 _SLR . The piping of the flow path 10 _H2O2 is connected to the inflow port F2 of the mixing unit 50 _H2O2 . The outlet F3 of the mixing unit 50 _CHM is connected to the inlet F1 of the mixing unit 50 _SLR . The outlet F3 of the mixing unit 50 _SLR is connected to the inlet F1 of the mixing unit 50 _H2O2 . The outlet F3 of the mixing unit 50 _H2O2 is connected to the liquid outlet 79.

The ultrapure water transferred in the flow path 10 _DIW flows into the mixing unit 50 _CHM from the inflow port F1. The chemicals transferred in the flow path 10 _CHM flow into the mixing unit 50 _CHM from the inflow port F2. The slurry transferred in the flow path 10 _SLR flows into the mixing unit 50 _SLR from the inflow port F2. The hydrogen peroxide solution transferred in the flow path 10 _H2O2 flows into the mixing unit 50 _H2O2 from the inflow port F2.

FIG. 3A is a front view of the mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 . FIG. 3B is a view of FIG. 3A viewed from the direction of arrow B. FIG. 3C is a diagram showing the inside of FIG. 3B. FIG. 4 is a partial cross-sectional view of FIG. 3 (B). The mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 have a housing HZ having two inlets F1 and F2 and one outlet F3, and a stirring screw SCR housed in the housing HZ.

The main body of the housing HZ is a hollow cylinder having a diameter substantially the same as or slightly thicker than that of the pipes of the flow paths 10 _DIW , 10 _CHM , 10 _SLR , and 10 _H2O2 . The inflow port F1 is at one end in the extending direction of the main body of the housing HZ, and the outflow port F3 is at the other end. There is an inflow port F2 in the vicinity of the inflow port F1 on the side surface of the main body of the housing HZ. The inflow port F2 communicates with the main body of the housing HZ.

The inflow port F1 communicates with the pipe HK1 in the housing HZ. The tip of the pipe HK1 is connected to the stirring screw SCR. The inflow port F2 communicates with the pipe HK2 in the Uzing HZ. As shown in FIG. 4, two sides in the width direction at the lower end of the pipe HK2 are in contact with the inner peripheral surface of the pipe HK1. There are two liquid discharge ports HL1 and HL2 at the bottom of the pipe HK2 and at two positions slightly above the bottom. In the pipe HK1, the two liquid discharge ports HL1 and HL2 face the stirring screw SCR.

In the stirring screw SCR, N (N is a natural number of 2 or more, N = 5 in the example of FIG. 3C) of the shaft rod AXS is spaced by VL-k (k = 1 to N). It is placed open. The shaft rod AXS is supported at the inlet F1 and the outlet F3 of the housing HZ. The torsion blade VL-k has a shape twisted half a turn (180 degrees) along the outer peripheral surface of the shaft rod AXS. The plurality of twisting blades VL-k (k = 1 to N) are arranged so as to be out of phase by 90 degrees, and the twisting blades VL-k that are in phase with each other are orthogonal to each other by 90 degrees. The intervals between the twisting blades VL-k before and after the phase are equal. The distance between the twisting blades VL-k before and after each other is shorter than the dimension (width in the front-rear direction) of the twisting blades VL-k itself.

Two liquid flowing from the mixing unit _{50 CHM} inlets F1 and inlet F2 in mixing unit ₅₀ in _CHM (ultrapure water and chemical) is mixed with each other while being agitated in the mixing unit _{50 CHM,} two liquid Is _delivered from the outlet F3 of the mixing unit 50 _CHM .

Two types of liquids (liquid containing ultrapure water and chemicals and slurry) flowing into the mixing unit 50 _{SLR from} the inflow ports F1 and F2 of the mixing unit 50 _SLR shall pass through the stirring screw SCR in the mixing unit 50 _SLR . As a result, the two types of liquids are mixed while being agitated, and the liquids obtained by mixing the two types of liquids are sent out from the outlet F3 of the mixing unit 50 _SLR .

The two types of liquids (liquid containing ultrapure water, chemicals, and slurry and hydrogen peroxide solution) that flowed into the mixing unit 50 _{H2O2 from} the inflow port F1 and the inflow port F2 of the mixing unit 50 _H2O2 are contained in the mixing unit 50 _H2O2 . The liquids in which the two types of liquids are mixed are sent out from the outlet F3 of the mixing unit 50 _H2O2 .

In FIG. 1, the flow rate sensor 61 _CHM detects the flow rate per unit time of the liquid (ultrapure water) at the position immediately before the inflow port F1 of the mixing unit 50 _CHM in the mixing flow path 40, and outputs the flow rate detection signal. Output. The flow rate sensor 62 _CHM detects the flow rate per unit time of the liquid (chemical) at the position immediately before the inflow port F2 of the mixing unit 50 _CHM in the mixing flow path 40, and outputs a flow rate detection signal. The flow rate sensor 63 _CHM detects the flow rate per unit time of the liquid (the liquid in which ultrapure water and chemicals are mixed) at the position immediately after the outlet F3 of the mixing unit 50 _CHM in the mixing flow path 40, and detects the flow rate. Output a signal. The concentration sensor 64 _CHM detects the turbidity of the liquid at the position immediately after the outlet F3 of the mixing unit 50 _CHM in the mixing flow path 40 as the concentration of the liquid, and outputs a concentration detection signal.

The flow rate sensor 61 _SLR detects the flow rate per unit time of the liquid (liquid containing ultrapure water and chemicals) at the position immediately before the inflow port F1 of the mixing unit 50 _SLR in the mixing flow path 40, and detects the flow rate. Is output. The flow rate sensor 62 _SLR detects the flow rate per unit time of the liquid (slurry) at the position immediately before the inflow port F2 of the mixing unit 50 _SLR in the mixing flow path 40, and outputs a flow rate detection signal. The flow rate sensor 63 _SLR detects the flow rate per unit time of the liquid at the position immediately after the outlet F3 of the mixing unit 50 _SLR (the liquid in which ultrapure water, chemicals, and slurry are mixed) in the mixing flow path 40, and the flow rate. Outputs the detection signal of. The concentration sensor 64 _SLR detects the turbidity of the liquid at the position immediately after the outlet F3 of the mixing unit 50 _SLR in the mixing flow path 40 as the concentration of the liquid, and outputs a concentration detection signal.

The flow rate sensor 61 _H2O2 detects the flow rate per unit time of the liquid (liquid containing ultrapure water, chemicals, and slurry) at the position immediately before the inflow port F1 of the mixing unit 50 _H2O2 in the mixing flow path 40, and the flow rate. Outputs the detection signal of. The flow rate sensor 62 _H2O2 detects the flow rate per unit time of the liquid (hydrogen peroxide solution) at the position immediately before the inflow port F2 of the mixing unit 50 _H2O2 in the mixing flow path 40, and outputs a flow rate detection signal. The flow rate sensor 63 _H2O2 is a liquid (a liquid in which ultrapure water, chemicals, slurry, and hydrogen peroxide solution are mixed) located immediately after the outlet F3 of the mixing unit 50 _H2O2 in the mixing flow path 40 per unit time. Detects the flow rate and outputs the flow rate detection signal. The concentration sensor 64 _H2O2 detects the turbidity of the liquid at the position immediately after the outlet F3 of the mixing unit 50 _H2O2 in the mixing flow path 40 as the concentration of the liquid, and outputs a concentration detection signal.

The PLC 70 is a device that serves as a control means for the polishing liquid supply device 2. The PLC 70 includes a first control for controlling the operation of the flow controllers 15 _CHM , 15 _SLR , and 15 _H2O2 , which are flow rate adjusting means, according to the flow rate and concentration of the liquid in the mixing flow path 40, and a plurality of for each type of liquid. depending on the storage amount of the drum _{11 CHM, 11 SLR, 11 H2O2} , drum _{11 CHM, 11 SLR, 11 H2O2} and the flow path _{10 CHM, 10 SLR, 10} executes a second control for controlling communication with _H2O2 To do.

In more detail, in the first control, PLC70 is provided from the flow controller ₁₅ the opening degree of the flow rate adjusting valve _{26 CHM} of _CHM, flow sensor _{61 CHM,} 62 _{CHM, 63} CHM detection signal and the CMP polishing device 8 The opening degree is determined based on the relationship between the target value of the flow rate indicated by the set signal and the target value of the concentration indicated by the set signal given from the CMP polishing device 8 and the detection signal of the density sensor 64 _CHM. The opening degree of the flow rate adjusting valve 26 _CHM is corrected based on the detection signals of the flow rate sensors 61 _CHM , 62 _CHM , 63 _CHM , and the detection signals of the concentration sensor 64 _CHM .

Specifically, in the PLC70, when the flow rate indicated by the detection signals of the flow rate sensors 61 _CHM , 62 _CHM , and 63 _CHM is larger than the target value of the flow rate and the difference is greater than or equal to the predetermined value, the flow rate adjusting valve 26 _CHM is opened. A control signal instructing to reduce the degree is supplied to the flow controller 15 _CHM . Further, in the PLC 70, when the flow rate indicated by the detection signals of the flow rate sensors 61 _CHM , 62 _CHM , and 63 _CHM is smaller than the target value and the difference is equal to or more than a predetermined value, the opening degree of the flow rate adjusting valve 26 _CHM is increased. A control signal indicating the above is supplied to the flow controller 15 _CHM .

Further, the PLC 70 controls to instruct to reduce the opening degree of the flow rate adjusting valve 26 _CHM when the concentration indicated by the detection signal of the concentration sensor 64 _CHM is larger than the target value of the concentration and the difference is equal to or more than a predetermined value. The signal is supplied to the flow controller 15 _CHM . Further, when the concentration indicated by the detection signal of the concentration sensor 64 _CHM is smaller than the target value and the difference is equal to or more than a predetermined value, the PLC 70 sends a control signal instructing to increase the opening degree of the flow rate adjusting valve 26 _CHM. Supply.

Similarly, the PLC 70 sets the opening degree of the flow rate adjusting valve 26 _SLR of the flow controller 15 _SLR to the target value of the flow rate indicated by the detection signals of the flow rate sensors 61 _SLR , 62 _SLR , 63 _{SLR and} the setting signal given from the CMP polishing device 8. The opening degree is determined based on the relationship with the density sensor 64 _SLR and the relationship between the detection signal of the density sensor 64 _SLR and the target value of the density indicated by the setting signal given from the CMP polishing device 8, and the subsequent flow rate sensors 61 _SLR , 62 _SLR , detection signals of 63 _SLR, and corrects the opening degree of the flow rate adjusting valve _{26 SLR} on the basis of a detection signal of the density sensor _{64 SLR.}

Further, the PLC 70 sets the opening degree of the flow rate adjusting valve 26 _H2O2 of the flow controller 15 _H2O2 as the target value of the flow rate indicated by the detection signals of the flow rate sensors 61 _H2O2 , 62 _H2O2 , 63 _{H2O2 and} the setting signal given from the CMP polishing device 8. The opening degree is determined based on the relationship between the above and the detection signal of the density sensor 64 _H2O2 and the target value of the density indicated by the setting signal given from the CMP polishing device 8, and the subsequent flow rate sensors 61 _H2O2 , 62 _H2O2 , 63. detection signals of _{H2 O2,} and corrects the opening degree of the flow rate adjusting valve _{26 H2 O2} based on the detection signal of the density sensor _{64 H2 O2.}

In the second control, PLC70, based on the detection signal of the pressure sensor _{13 CHM} plurality of drums _{11 CHM} where chemicals are stored, along with determining the pressure of the drum _{11 CHM,} based on the detection signal of the load cell _{12 CHM} , Drum 11 _CHM chemical storage amount is determined. As shown in FIG. 5, PLC70 is the amount of liquid stored in the drum _{11 CHM} in communication with the inner passage _{10 CHM} plurality of drum _{11 CHM} (drum 1 in the example of FIG. 5) is a predetermined value _{TH LQ} 1 when below, along with releasing the communication between the drum ₁₁ the first valve to close the flow path _{10 CHM} tubes _CHM, drum _{11 CHM} by closing the valve of the second tube of the drum _{11 CHM} Stop pressurizing. At this time, among the other drum _{11 CHM,} storage amount of liquid exceeds the predetermined amount, the drum _{11 CHM} pressure exceeds a predetermined value _{TH PR} 1 (drum 2 in the example of FIG. 5) _Is selected, and the valve of the first tube of the selected drum 11 _CHM is opened to communicate with the flow path 10 _CHM . At this time, among the other drum _{11 CHM,} storage amount of liquid exceeds the predetermined amount, (drum 3 in the example of FIG. 5) drum _{11 CHM} the internal pressure has not reached the predetermined value _{TH PR} 1 selecting, opening the valve of the second tube of the selected drum _{11 CHM} that drum _{11 CHM} nitrogen is sent from the gas pressure portion _{14 CHM} to be to start pressurization of the drum _{11 CHM.}

Similarly, the PLC 70 controls the communication between the drum 11 _SLR in which the slurry is stored and the flow path 10 _SLR based on the detection signals of the pressure sensor 13 _SLR and the load cell 12 _SLR , and controls the communication between the pressure sensor 13 _H2O2 and the load cell 12 _H2O2. The communication between the drum 11 _H2O2 in which the hydrogen peroxide solution is stored and the flow path 10 _H2O2 is controlled based on the detection signal of.

The above is the details of the configuration of the present embodiment. According to this embodiment, the following effects can be obtained.

First, in the present embodiment, there is a mixing flow path 40 that communicates with the flow path 10 _CHM , 10 _SLR , and 10 _{H2O2 to} which ultrapure water, chemicals, slurry, and hydrogen peroxide solution are transferred, and this mixing flow path. In No. 40, a plurality of types of liquids are blended, and the blended liquids are supplied to the CMP polishing apparatus 8 as a polishing liquid. Therefore, in the present embodiment, it is not necessary to provide a mixing tank for mixing a plurality of types of liquids. Therefore, the liquid does not stay in the mixing tank and coagulation sedimentation does not occur, and the polishing liquid having a uniform concentration can be stably supplied to the CMP polishing apparatus 8.

Secondly, in the present embodiment, since there is no compounding tank, it is not necessary to install a drying prevention mechanism or a solidification prevention mechanism in the compounding tank. Along with this, it is not necessary to replace consumables that play a part of the drying prevention mechanism and the solidification prevention mechanism, so that the number of maintenance steps of the polishing liquid supply device 2 can be significantly reduced.

Third, in the present embodiment, the blending flow path 40 is arranged immediately before the liquid delivery port 79 leading to the CMP polishing apparatus 8. Therefore, after a plurality of types of liquids are mixed to obtain a polishing liquid, the polishing liquid can be used for polishing the wafer 88 of the CMP polishing apparatus 8 in a fresh state. Therefore, chemical attacks are less likely to occur, and coarse particles that cause scratches can be reduced. In addition, the polishing liquid does not change with time between preparation and use. As a result, stable polishing characteristics can be obtained.

Fourth, in the present embodiment, the mixing flow path 40 is provided with a plurality of mixing units 50 having two inlets F1 and F2 and one outlet F3 connected in a plurality of stages. .. Therefore, it is possible to accurately perform stepwise preparation of three or more kinds of liquids, such as blending chemicals in ultrapure water → further blending slurry → further blending hydrogen peroxide solution.

Fifth, in the present embodiment, a stirring screw SCR is provided in the mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 . The liquid that has flowed into the mixing unit 50 from the inflow port F1 and the liquid that has flowed into the mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 from the inflow port F2 merge at the liquid discharge ports HL1 and HL2 of the pipe HK2 in the pipe HK1. After this merging, the two kinds of liquids pass through the torsion blade VL-1 → the torsion blade VL-2 → the torsion blade VL-3 ... → the torsion blade VL-5 in this order. As shown in FIG. 6 (A), each time the two kinds of liquids pass through one twisting blade VL-k, two kinds of liquids are applied to one twisting surface side of the twisting blade VL-k and the other twisting surface on the back side thereof. It is roughly divided into equal parts on the side. Further, as shown in FIG. 6B, the two types of liquid are applied to the shaft rod from the side of the shaft rod AXS to the side of the inner wall surface or from the side of the inner wall surface on the twist surface of the torsion blade VL-k. Reflux to the side of AXS, and so on. Further, as shown in FIG. 6C, the rotation directions of the two types of liquids are reversed between the two torsion blades VL-k that are in phase with each other. A liquid obtained by diluting the slurry with a uniform concentration is obtained by the three actions of the dividing action, the reflux action, and the reversing action. Therefore, the time required for stirring can be significantly shortened as compared with the conventional method of storing the liquid in a mixing tank and stirring it with a stirring device. Further, the mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 are less bulky than the mixing tank, and the composition itself of the mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 is simpler than that of the mixing tank. Therefore, the device design of the CMP system 1 can be simplified and the delivery time of the system can be shortened.

Sixth, in the present embodiment, the concentration sensors 64 _CHM , 64 _SLR , and 64 _H2O2 that detect the turbidity of the liquid in the mixing flow path 40 as the liquid concentration, and the flow _rates 10 _CHM , 10 _SLR , and 10 _H2O2 . A flow controller 15 _CHM , 15 _SLR , 15 _H2O2 for adjusting the flow rate of the liquid is provided, and the PLC 70 has a flow controller 15 _CHM , 15 _SLR based on the relationship between the concentration of the liquid in the mixing flow path 40 and the target value. , 15 Controls the operation of _H2O2 . Therefore, the concentration of the slurry can be efficiently adjusted by setting the target value of the concentration by the CMP polishing apparatus 8. In addition, it is possible to flexibly respond to changes in circumstances such as a change in the dilution ratio of the polishing liquid, a change in the wafer 88, and a change in the amount of polishing removed on the CMP polishing apparatus 8 side.

Seventh, in the present embodiment, the gas pressurizing unit 14 _CHM , 14 _SLR pushes the liquid into the flow path 10 _CHM , 10 _SLR , 10 _H2O2 by sending the inert gas into the drums 11 _CHM , 11 _SLR , 11 _H2O2 . , 14 _H2O2 . Therefore, the liquid in the drums 11 _CHM , 11 _SLR , and 11 _H2O2 can be stably supplied to the mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 of the mixing flow path 40 without pulsating. In addition, the polishing characteristics of the slurry can be improved. Explaining this in more detail, when a diaphragm pump or the like using compressed air as a drive source is used for pumping the slurry, the slurry is stressed or damaged by repeating the pushing and pulling operation of the diaphragm. Polishing with a damaged slurry causes deterioration of polishing characteristics. On the other hand, when the transfer of the slurry from the drum 11 _SLR to the flow path 10 _SLR becomes pumpless, the pump does not damage the slurry. As a result, a high-quality slurry can be supplied to the polishing liquid supply device 2.

Eighth, in the present embodiment, the CMP polishing apparatus 8 is provided with an operator for setting a target value of the flow rate or concentration of the liquid, and the target value of the flow rate or concentration is set in the CMP polishing apparatus 8. In this case, the setting signal is supplied from the CMP polishing device 8 to the PLC 70 of the polishing liquid supply device 2 → the control signal is supplied from the PCL 70 to the flow controllers 15 _CHM , 15 _SLR , and 15 _H2O2 → the flow rate changes instantly according to the control signal → the flow rate. Sensor 61 _CHM , 62 _CHM , 63 _CHM , 61 _SLR , 62 _SLR , 63 _SLR , 61 _H2O2 , 62 _H2O2 , 63 _H2O2 , concentration sensor 64 _CHM , 64 _SLR , 64 _H2O2 detect the flow rate and concentration after changing the opening. → Flow controller 15 _CHM , 15 _SLR , 15 _H2O2 flow rate adjustment valves 26 _CHM , 26 _SLR , 26 so that the flow rate or concentration setting signal and the sensor detection signal match by the procedure of correction according to the detection result. The opening degree of _H2O2 is automatically adjusted. Therefore, the flow rate and concentration of the liquid can be efficiently adjusted under the control of the CMP polishing apparatus 8.

<Second Embodiment>
FIG. 7 is a diagram showing the overall configuration of the CMP system 1 including the polishing liquid supply device 2 according to the second embodiment of the present invention. In FIG. 7, the same elements as those of the polishing liquid supply device 2 of the first embodiment are designated by the same reference numerals. The mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 of the polishing liquid supply device 2 of the first embodiment have a structure having a cylindrical body having a diameter substantially the same as or slightly thicker than that of the flow paths 10 _CHM , 10 _SLR , and 10 _H2O2. In this mixing unit 50 _CHM , 50 _SLR , 50 _H2O2 , a plurality of liquids were prepared in-line. On the other hand, the mixing unit 50A of the polishing liquid supply device 2 of the present embodiment has a mixing tank 52A and a stirring device 59A, and a plurality of liquids are stirred and mixed in the tank 52A. ing.

The polishing liquid supply device 2 of the CMP system 1 includes a PLC 70, an ultrapure water inlet 29 connected to an external ultrapure water supply source, a drum 11 _CHM in which chemicals are stored, and a drum 11 _SLR in which slurry is stored. , Drum 11 _H2O2 in which hydrogen peroxide solution is stored, liquid transfer channel 10 _DIW in which ultrapure water is transferred, liquid transfer channel 10 _CHM in which chemicals are transferred, liquid transfer channel 10 in which slurry is transferred. _{From the SLR} , the liquid transfer flow path 10 _H2O2 to which the hydrogen peroxide solution is transferred, and the mixing unit 50A and the mixing unit 50A connected to the pipes of these flow paths 10 _CHM , 10 _SLR , and 10 _H2O2 to the CMP polishing apparatus 8. It has a flow path 40A leading to it.

The flow path 40A is a circulation flow path that returns to the mixing tank 52A of the mixing unit 50A via the branch point 17A toward the CMP polishing apparatus 8.

The mixing unit 50A obtains a polishing liquid used for polishing the CMP polishing apparatus 8 by blending four types of liquids: chemical, ultrapure water, slurry, and hydrogen peroxide solution. The mixing unit 50A includes a housing 51A, a mixing tank 52A, a stirrer 59A, a pressurizing tank 53A, a filling amount sensor 56A, a flow controller 55A, and a gas pressurizing unit 54A.

The housing 51A has a hollow rectangular parallelepiped shape. At the upper part of the housing 51A, there is a compounding tank 52A, and at the lower part of the housing 51A, there are a plurality of (three in the example of FIG. 7) pressure tanks 53A.

The compounding tank 52A has a hollow cylindrical shape. Ultrapure water transferred in the flow path 20 _DIW , chemicals transferred in the flow path 10 _CHM , slurry transferred in the flow path 10 _SLR, and hydrogen peroxide solution transferred in the flow path 10 _H2O2 are mixed tank 52A. Flow into. The stirring device 59A stirs and mixes the four types of liquids that have flowed into the blending tank 52A.

At the bottom of the compounding tank 52A, there is a pipe extending downward. This pipe is branched into a plurality of pipes, and the branched pipes are connected to the inflow ports of the plurality of pressure tanks 53A. The pressurizing tank 53A has a cylindrical shape. The pressurizing tank 53A is arranged at a position directly below the compounding tank 52A in the housing 51A so that the inflow port faces upward and the outlet faces downward.

The polishing liquid obtained by stirring four kinds of liquids in the compounding tank 52A flows into the pressure tank 53A through the lower pipe due to its own weight, and is filled in the pressure tank 53A. An on-off valve VLU is provided at the liquid inlet of the pressurizing tank 53A, and an on-off valve VLL is provided at the liquid outlet. The on-off valves VLU and VLL of the pressurizing tank 53A open when an open signal is given, and close when a close signal is given.

The filling amount sensor 56A detects the filling amount of the liquid in the pressurizing tank 53A and outputs a detection signal. Specifically, the filling amount sensor 56A outputs a signal indicating that when the filling amount of the liquid in the pressurizing tank 53A falls below a predetermined value.

Under the control of the flow controller 55A, the gas pressurizing unit 54A delivers nitrogen, which is an inert gas, from the gas inlet at the upper part of the pressurizing tank 53A into the pressurized tank 53A. The liquid in the pressurized tank 53A is pushed out from the outlet at the lower part of the pressurized tank 53A by the pressure of nitrogen.

The PLC 70 is a device that serves as a control means for the polishing liquid supply device 2. The PLC 70 controls switching of the pressure tank 53A that communicates with the mixing flow path 40.

More specifically, the presence / absence of the output of the signal ST in the filling amount sensor 56A is monitored. The PLC70 closes the on-off valves VLU and VLL of the pressurizing tank 53A whose filling amount is less than a predetermined amount for the three pressurizing tanks 53A, and opens the on-off valves VLU and VLL of another pressurizing tank 53A. Control is repeated recursively.

The above is the details of the configuration of the present embodiment. According to this embodiment, the following effects can be obtained.
First, in the present embodiment, the polishing liquid obtained by mixing the liquid in the mixing tank 52A of the mixing unit 50A is filled in the pressure tank 53A, and the gas pressurizing unit 54A is not in the pressure tank 53A. The active gas is sent out to push the polishing liquid in the pressure tank 53A into the path leading to the CMP polishing apparatus 8. Therefore, it is possible to stably supply the ultra-high precision polishing liquid without pulsation to the CMP polishing apparatus 8.

Secondly, in the present embodiment, the mixing tank 52A for storing the polishing liquid obtained by mixing the liquid is provided, and the flow path leading to the CMP polishing device 8 branches from the mixing tank 52A toward the CMP polishing device 8. It is a circulation flow path that returns to the mixing tank 52A via the point 17A. Therefore, the liquid does not stay in the compounding tank 52A and coagulation sedimentation does not occur, and the polishing liquid having a uniform concentration can be stably supplied to the CMP polishing apparatus 8.

Third, in the present embodiment, the pressurizing tank 53A is arranged below the compounding tank 52A so that the liquid flows from the compounding tank 52A into the pressurizing tank 53A due to the weight of the liquid in the compounding tank 52A. It has become. Therefore, it is not necessary to provide a special device such as a pump in the compounding tank 52A, and the liquid can be transferred from the compounding tank 52A to the pressurized tank 53A without risk of oxidation of the polishing liquid or change in the composition.

Fourth, in the present embodiment, the pressure tank 53A has a tubular shape, and the pressure tank 53A has a liquid inlet from the mixing tank 52A to the pressure tank 53A facing up. The liquid outlet from 53A to the CMP polishing apparatus 8 is arranged so as to be downward. Therefore, the flow of the liquid of the compounding tank 52A → the pressure tank 53A → the CMP polishing apparatus 8 can be made smoother.

Fifth, in the present embodiment, the number of the pressurizing tanks 53A is a plurality, and the PLC70 as a control means closes the on-off valves VLU and VLL of the pressurizing tanks 53A whose filling amount is less than a predetermined amount. The control of opening the on-off valves VLU and VLL of another pressurizing tank 53A is recursively repeated. Therefore, according to the present embodiment, it is possible to reliably prevent the occurrence of a situation in which the liquid in the pressure tank 53A is exhausted and the supply of the liquid to the CMP polishing apparatus 8 is interrupted.

<Modification example>
Although the first and second embodiments of the present invention have been described above, the following modifications may be added to these embodiments.

(1) The order of blending a plurality of types of liquids in the blending flow path 40 of the first embodiment is not limited to that of the first embodiment. For example, the slurry and chemicals may be first mixed, then hydrogen peroxide solution may be mixed thereto, and finally ultrapure water may be prepared and diluted.

(2) In the first embodiment, the drum _{11 CHM, 11 SLR, 11 H2O2} , nitrogen delivery, the liquid in the drum _{11 CHM, 11 SLR, 11 H2O2} , by the pressure of nitrogen, the drum ₁₁ CHM, 11 _It was supposed to be pushed out from _SLR , 11 _H2O2 . However, another inert gas (eg, argon) may be _{delivered to} the drums 11 _CHM , 11 _SLR , 11 _H2O2 .

(3) In the first embodiment, the flow path 10 _CHM is connected to the inflow port F2 of the mixing unit 50 _CHM , the flow path 10 _SLR is connected to the inflow port F2 of the mixing unit 50 _SLR , and the flow path 10 _H2O2 is connected to the mixing unit 50. It was configured to be connected to the inflow port F2 of _H2O2 . However, the flow path 10 _CHM is connected to the inflow port F1 of the mixing unit 50 _CHM , the flow path 10 _SLR is connected to the inflow port F1 of the mixing unit 50 _SLR , and the flow path 10 _H2O2 is connected to the inflow port F1 of the mixing unit 50 _H2O2 . It may be configured as.

(4) In the second embodiment, the liquid inlet is located above the pressurized tank 53A, and the liquid outlet is located below the pressurized tank 53A. However, both the inlet and outlet of the liquid may be provided in the lower part of the pressurized tank 53A. For example, as shown in FIG. 8, a pipe is provided at the lower part (bottom) of the pressure tank 53A, and the lower part of this pipe is branched into a T-shape on the inflow side and the outflow side of the liquid, and the pipe on the inflow side. The first valve VAL1 may be provided in the pipe, and the second valve VAL2 may be provided in the pipe on the outflow side. Then, the PLC 70 opens the first valve VAL1 and closes the second valve VAL1 until the filling amount of the liquid in the pressure tank 53A reaches a predetermined amount (for example, 90%), and the liquid is filled in the pressure tank 53A. When the filling amount of the liquid in the pressure tank 53A reaches a predetermined amount, the first valve VAL1 is closed and the second valve VAL1 is opened, and the liquid in the pressure tank 53A is pushed out by the pressure of nitrogen. May be repeated recursively.

(5) In the first embodiment, the drums 11 _CHM , 11 _SLR , and 11 _H2O2 and the mixing units 50 _CHM , 50 _SLR , and 50 _H2O2 do not need to be installed on the same floor. The drum may be installed on the production plant side, and the liquid may be supplied from the drums 11 _CHM , 11 _SLR , 11 _H2O2 on the production plant side to the mixing units 50 _CHM , 50 _SLR , 50 _H2O2 as a house line.

(6) In the first embodiment, the liquid storage amount of the drum 11 _CHM (drum 1 in the example of FIG. 5) communicating with the flow path 10 _CHM among the plurality of drum 11 _CHMs has a predetermined value TH _LQ 1. Before falling below, that is, at a predetermined timing while the liquid is being transferred from one drum 11 _CHM to the flow path 10 _CHM (for example, the amount of liquid stored in drum 1 or drum 2 is higher than the predetermined value TH _LQ 1). The timing when the liquid falls below the large predetermined value TH _LQ 1', the timing when the liquid transfer from the tram 1 or the drum 2 is started, or the timing when the predetermined time elapses from the start of the liquid transfer from the drum 1 or the drum 2) in, among other drum _{11 CHM,} storage amount of liquid has reached the predetermined value _{TH LQ} 1, the pressure does not reach the predetermined value _{TH PR} 1 drum _{11 CHM} (eg the drum 3 in Fig. 5) selecting, opening the valve of the second tube of the selected drum _{11 CHM} that drum _{11 CHM} nitrogen is sent from the gas pressure portion _{14 CHM} to be, so as to start the pressurization of the drum _{11 CHM} May be good.

(7) In the first and second embodiments, the blending flow path 40 does not need to be arranged immediately before the liquid outlet 79 leading to the CMP polishing apparatus 8, and is provided corresponding to the liquid outlet 79. Just do it. A blending flow path 40 may be provided inside the CMP polishing apparatus 8. Further, the unit may be a unit in which the CMP polishing device 8 and the polishing liquid supply device 2 are integrated, or the polishing liquid supply device 2 may be mounted in the CMP polishing device 8. Further, the compounding flow path 40 may be arranged at a position separated from the liquid outlet 79 by a predetermined distance, or may be arranged at a position where the slurry or chemical is not damaged.

(8) In the first and second embodiments, the drum 11 _CHM , 11 _SLR , 11 _H2O2 Drum 11 to prevent expansion and outbursts _CHM , 11 _SLR , 11 _H2O2 Two inlets and outlets at the top, flow path 10 at the top _CHM 10, 10 _SLR 10, 10 _H2O2 A degassing flow path (drain) is provided at the inlet on the opposite side to the drum 11. _CHM , 11 _SLR , 11 _H2O2 Safety valves, pressure sensors, and control functions may be added to. The control in this case is the drum 11 _CHM , 11 _SLR , 11 _H2O2 When the pressure exceeds a certain pressure, the safety valve opens and the drum 11 _CHM , 11 _SLR , 11 _H2O2 Release the pressure inside, drum 11 _CHM , 11 _SLR , 11 _H2O2 It is advisable to repeat the control of closing the safety valve when the pressure drops to the set pressure.

1 Drum 2 Polishing liquid supply device 3 Drum 8 Polishing device 11 Drum 14 Gas pressurizing part 17A Branch point 21 Low pressure valve 26 Flow rate adjustment valve 29 Ultrapure water inlet 31 Top plate 32 Bottom plate 33 Side plate 38 Air cylinder 40 Mixing flow path 40A Flow path 50 Mixing unit 50A Mixing unit 51A Housing 52A Tank 52A Mixing tank 53A Pressurizing tank 54A Gas pressurizing part 55A Flow controller 56A Filling amount sensor 59A Stirrer 70 PLC
79 Outlet 81 Head 83 Surface plate 84 Polishing pad 85 Nozzle 88 Wafer 89 Liquid inlet 91 Tank 92 Pump 311 312 321 322 Plate

Claims (2)

A polishing liquid supply device that supplies a polishing liquid to a CMP polishing device.
A plurality of liquid transfer channels for transferring the slurry and a plurality of liquids including other liquids to be mixed with the slurry, respectively.
A mixing flow path arranged corresponding to a liquid inlet / outlet leading to the CMP polishing apparatus, which communicates with the plurality of liquid transfer flow paths and uses the liquid prepared by mixing the plurality of liquids as the polishing liquid. Equipped with a mixing flow path to supply to the polishing equipment,
In the compounding flow path,
A polishing liquid supply device characterized in that a plurality of mixing units having two inlets and one outlet are connected in a plurality of stages. The plurality of mixing units include a first mixing unit, a second mixing unit, and a third mixing unit.
One inlet of the first mixing unit is a liquid transfer channel for pure water, the other inlet is a liquid transfer channel for chemicals, and the outlet is one inlet of the second mixing unit. Each is connected,
The other inlet of the second mixing unit is connected to the liquid transfer flow path of the slurry, and the outlet is connected to one inlet of the third mixing unit.
Claim 1 is characterized in that one inlet of the third mixing unit is connected to a liquid transfer flow path of hydrogen peroxide solution, and the outlet is connected to a liquid inlet to the CMP polishing apparatus. The polishing liquid supply device according to.