JP2004281464A - Device and method for treating substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the occurrence of fluctuation in the mixing ratios of a plurality of kinds of treating liquids supplied to a substrate. <P>SOLUTION: A pure water introducing path 5 and a liquid chemical introducing path 6 are connected to a mixing valve 4 used for preparing the mixed solution of a liquid chemical and pure water. A sucking/delivering path 56 is branched from the pure water introducing path 5 and a pure water syringe 57 used for sending pure water to the pure water introducing path 5 at a fixed flow rate is connected to the sucking/delivering path 56. On the other hand, another sucking/discharging path 65 is branched from the liquid chemical introducing path 6 and a liquid chemical syringe 66 used for sending the liquid chemical to the liquid chemical introducing path 6 at a fixed flow rate is connected to the sucking/delivering path 65. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate processing apparatus and a substrate processing method for processing a substrate. Substrates to be processed include semiconductor wafers, glass substrates for liquid crystal display devices, glass substrates for plasma displays, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, substrates for photomasks, and the like.
[0002]
[Prior art]
2. Description of the Related Art In the manufacturing process of semiconductor devices and liquid crystal display devices, a single-wafer-type substrate processing apparatus that processes substrates one by one in order to perform surface treatment with a processing liquid on substrates such as semiconductor wafers and glass substrates for liquid crystal display panels. May be used. In this type of substrate processing apparatus, a single type of processing liquid is rarely used, and a mixed liquid obtained by mixing a plurality of types of processing liquids (chemical liquid or pure water) at an appropriate ratio is generally used.
[0003]
FIG. 7 is a diagram showing a simplified configuration of a conventional substrate processing apparatus. This conventional substrate processing apparatus includes a tank 101 for storing a mixed liquid (processing liquid). The processing liquid for processing the substrate is pumped out of the tank 101 by a pump 102, and the mixed liquid is supplied. The passage 103 is sent toward the nozzle 104. In the middle of the mixed liquid supply passage 103, a filter 105 for removing foreign matter in the mixed liquid is provided downstream of the pump 102 with respect to the flow direction of the mixed liquid, and a nozzle 104 is provided further downstream of the filter 105. And a mixed liquid supply valve 106 for switching the discharge / stop of the mixed liquid. Further, a mixed liquid return path 107 is branched and connected to the mixed liquid supply path 103 at a branch point J between the filter 105 and the mixed liquid supply valve 106. The end of the mixed liquid return path 107 is connected to the tank 101, and a mixed liquid return valve 108 is provided in the middle of the mixed liquid return path 107.
[0004]
During a period in which the mixed liquid is not supplied to the surface of the substrate, the pump 102 is driven while the mixed liquid supply valve 106 is closed and the mixed liquid return valve 108 is opened, so that the tank 101 and the mixed liquid supply path 103 are opened. The mixed liquid circulates in the processing liquid circulation path including the mixed liquid return path 107. Then, when it is time to supply the mixed liquid to the surface of the substrate, the mixed liquid return valve 108 is closed while the pump 102 is driven, and the mixed liquid supply valve 106 is opened almost simultaneously. Accordingly, the mixed liquid flowing through the mixed liquid supply path 103 flows from the branch point J toward the nozzle 104, and is discharged from the nozzle 104 toward the surface of the substrate.
[0005]
[Patent Document 1]
JP-A-2002-206957
[0006]
[Problems to be solved by the invention]
In such a configuration in which the mixed liquid obtained by mixing a plurality of types of processing liquids at an appropriate ratio is stored in the tank 101, the chemical change of the mixed liquid stored in the tank 101 and the chemical component with time elapse. Precipitates, and as a result, the mixing ratio of various processing liquids contained in the mixed liquid changes. If the mixing ratio of the various processing liquids changes, the intended processing effect cannot be obtained, and processing defects such as insufficient cleaning and insufficient etching may occur.
[0007]
Therefore, an object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of preventing a variation in a mixing ratio of a plurality of types of processing liquids supplied to a substrate and thereby performing a good processing on the substrate. To provide.
[0008]
Means for Solving the Problems and Effects of the Invention
According to a first aspect of the present invention, there is provided a substrate processing apparatus for performing a processing by supplying a mixed liquid of a first processing liquid and a second processing liquid to a substrate (W). A substrate rotating unit (1) for rotating the substrate while holding the substrate, and a nozzle (2; 20; 200) for supplying a mixed liquid of the first processing liquid and the second processing liquid to the substrate rotated by the substrate rotating unit ), A first processing liquid supply path (6) through which the first processing liquid supplied to the nozzle flows, and a second processing liquid supply path through which the second processing liquid supplied to the nozzle flows (5) and a first processing liquid syringe (66) connected to the first processing liquid supply path for sending out the first processing liquid to the first processing liquid supply path. Is a substrate processing apparatus.
[0009]
The first treatment liquid syringe is, for example, a hollow cylindrical cylinder (661) having a constant inner diameter, and is inserted into the cylinder to maintain liquid tightness with respect to the inner peripheral surface of the cylinder. A piston (662) that is slidable while the substrate is being processed. In this case, the substrate processing apparatus further includes a piston drive mechanism (67) for reciprocating the cylinder with respect to the piston at a constant speed. Including.
It should be noted that the alphanumeric characters in parentheses indicate corresponding components and the like in embodiments described later. Hereinafter, the same applies in this section.
[0010]
According to the configuration of the first aspect, the first processing liquid can be sent out from the first processing liquid syringe to the first processing liquid supply path at a constant flow rate. Therefore, if the flow rate of the second processing liquid flowing through the second processing liquid supply path is constant, the first processing liquid flowing through the first processing liquid supply path is combined with the second processing liquid flowing through the second processing liquid supply path. By mixing the first processing liquid and the second processing liquid, a mixed liquid in which the first processing liquid and the second processing liquid are mixed at a constant mixing ratio can be prepared. The mixed liquid thus created does not cause a variation in the mixing ratio between the first processing liquid and the second processing liquid, so that the surface of the substrate can be satisfactorily processed without causing processing defects such as insufficient cleaning. Can be. In particular, this configuration is effective in maintaining a constant mixing ratio of these mixed liquids when the ratio of the first processing liquid is smaller than the ratio of the second processing liquid.
[0011]
The substrate processing apparatus is connected to the second processing liquid supply path to supply the second processing liquid at a constant flow rate to the second processing liquid supply path, and the second processing liquid is supplied to the second processing liquid supply path. A second processing liquid syringe (57) for sending out the second processing liquid to the liquid supply path may be further included. The second processing liquid syringe is, for example, a hollow cylindrical cylinder (571) having a constant inner diameter, and is inserted into the cylinder to maintain liquid tightness with respect to the inner peripheral surface of the cylinder. A piston drive mechanism (59) for reciprocating the cylinder at a constant speed with respect to the piston. Including.
[0012]
According to a third aspect of the present invention, in the substrate processing apparatus, the first processing liquid supply path and the second processing liquid supply path are connected at their respective ends, and the first processing liquid supply path flows from the first processing liquid supply path. A merging channel (3, 4) for merging the first processing liquid and the second processing liquid flowing from the second processing liquid supply path to supply a mixed liquid of the first processing liquid and the second processing liquid to the nozzle; May be further included.
Still further, when such a combined flow path is not provided, the nozzle is connected to each end of the first processing liquid supply path and the second processing liquid supply path, and A plurality of discharge ports (21 to 25) for discharging the first processing liquid flowing from the first processing liquid supply path and the second processing liquid flowing from the second processing liquid supply path toward the substrate are provided. The first processing liquid may be connected to the end of the first processing liquid supply path and the second processing liquid supply path. The first processing liquid flowing from the supply path and the second processing liquid flowing from the second processing liquid supply path are internally joined, and the mixed liquid of the first processing liquid and the second processing liquid is directed toward the substrate. It may be the one that discharges (200).
[0013]
When the nozzle has a plurality of discharge ports (case of claim 4), if the plurality of discharge ports are arranged close to each other, the first processing liquid and the second processing liquid are: The mixture is mixed between the time when the liquid is discharged from the discharge port and the time when the liquid is supplied to the substrate, and is supplied to the substrate as a mixed liquid of the first processing liquid and the second processing liquid. If the plurality of discharge ports are formed apart, the first processing liquid and the second processing liquid are separately supplied to the substrate and mixed on the substrate to form a mixed liquid.
[0014]
According to a sixth aspect of the present invention, there is provided a method of processing a substrate (W) using a mixed liquid of a first processing liquid and a second processing liquid, wherein a substrate to be processed is held by a substrate rotating means (1). Rotating the first processing liquid from the first processing liquid syringe (66) to the first processing liquid supply path (6); and supplying the second processing liquid to the second processing liquid supply path (5). Feeding the first processing liquid flowing through the first processing liquid supply path and the second processing liquid flowing through the second processing liquid supply path, and mixing the first processing liquid and the second processing liquid flowing through the second processing liquid supply path. Supplying a mixed liquid of a first processing liquid and a second processing liquid to a substrate to be processed.
[0015]
According to this method, the same effect as the effect described in claim 1 can be obtained.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a simplified diagram showing a configuration of a substrate processing apparatus according to an embodiment of the present invention. This substrate processing apparatus is a single-wafer-type substrate processing apparatus that processes wafers W, which are examples of substrates, one by one. The spin chuck 1 rotates while holding the wafer W substantially horizontally, and the spin chuck 1 And a nozzle 2 for supplying a processing liquid to the surface (upper surface) of the wafer W held by the nozzle 2. If the processing on the wafer W is a processing using a mixed liquid obtained by mixing a plurality of processing liquids at a predetermined ratio, for example, etching (cleaning) for removing unnecessary substances such as particles and various metal impurities from the surface of the wafer W ) Treatment or an oxidation treatment for forming an oxide film on the surface of the wafer W.
[0017]
The spin chuck 1 includes, for example, a spin shaft 11 extending in a substantially vertical direction, a spin base 12 attached to an upper end of the spin shaft 11, and a plurality of holding members disposed on a peripheral portion of the spin base 12. 13 are provided. The plurality of holding members 13 are arranged on a circumference corresponding to the outer shape of the wafer W, and hold the wafer W in a substantially horizontal posture by holding the peripheral surface of the wafer W at a plurality of different positions. be able to. Further, a rotation driving mechanism 14 including a driving source such as a motor is coupled to the spin shaft 11, and a driving force is applied from the rotation driving mechanism 14 to the spin shaft 11 in a state where the wafer W is held by the plurality of holding members 13. By inputting, the wafer W can be rotated about the center axis of the spin shaft 11 in a substantially horizontal posture.
[0018]
The spin chuck 1 is not limited to the one having such a configuration. For example, the lower surface of the wafer W may be held in a substantially horizontal posture by vacuum-sucking the lower surface of the wafer W. A vacuum suction type (vacuum chuck) that can rotate the held wafer W by rotating around may be employed.
To the nozzle 2, a mixed liquid of a chemical and DIW (deionized pure water) or HDIW (deionized warm pure water) is supplied from a mixed liquid supply path 3. A filter 31 for removing foreign matter in the mixed liquid flowing through the mixed liquid supply path 3 is provided in the middle of the mixed liquid supply path 3.
[0019]
The mixed liquid (mixed liquid used for processing the wafer W) flowing through the mixed liquid supply path 3 is introduced into the mixing valve 4 via a predetermined one of the chemical liquid introduction valves 41, 42, 43, and 44. It is prepared by mixing a chemical solution and pure water (DIW or HDIW) introduced from the pure water introduction path 5 at a predetermined mixing ratio.
For example, when the mixed liquid used for processing the wafer W is DHF (dilute hydrofluoric acid solution), the mixing valve 4 introduces HF (hydrofluoric acid) having a concentration of about 50% introduced through the chemical liquid introduction valve 41. And pure water introduced from the pure water introduction path 5 are mixed at a mixing ratio of HF: pure water = 1: 200. When the mixed liquid used for processing the wafer W is APM (ammonia / hydrogen peroxide solution), the mixing valve 4 has a concentration of about 30% introduced through the chemical liquid introduction valves 41 and 42, respectively. NH ₄ OH (aqueous ammonia) and about 30% H ₂ O ₂ (Hydrogen peroxide solution) and pure water introduced from the pure water introduction path 5 ₄ OH: H ₂ O ₂ : Pure water = 1: 2: 100. Further, when the mixed solution used for processing the wafer W is HPM (hydrochloric acid / hydrogen peroxide solution), the mixing valve 4 has a concentration of about 35% introduced through the chemical solution introduction valves 41 and 42, respectively. HCl (HCl) and about 30% H ₂ O ₂ And pure water introduced from the pure water introduction passage 5 is HCl: H ₂ O ₂ : Pure water = 1: 1: 50.
[0020]
In the following, a configuration for introducing pure water to mixing valve 4 and a chemical solution introducing valve 41 to mixing valve 4 will be described, taking as an example a case where the mixed liquid used for processing wafer W is DHF (dilute hydrofluoric acid solution). A configuration for introducing HF via the PC will be described. The configuration for introducing the chemical solution to the mixing valve 4 via the chemical solution introduction valves 42, 43, 44 is the same as the configuration for introducing the chemical solution to the mixing valve 4 via the chemical solution introduction valve 41.
[0021]
Pure water (DIW or HDIW) is selectively supplied to the pure water introduction path 5 via a DIW supply source valve 51 or an HDIW supply source valve 52. A regulator 53 for adjusting the flow pressure of the pure water supplied to the pure water introduction path 5 is provided in the pure water introduction path 5 in order from the upstream side with respect to the flow direction of the pure water. A syringe upstream valve 54 and a syringe downstream valve 55 for opening and closing the valve are interposed. Further, one end of a suction / discharge path 56 is branched and connected to the pure water introduction path 5 between a syringe upstream valve 54 and a syringe downstream valve 55. The other end of the suction / discharge path 56 is connected to a syringe 57 for pure water, and a syringe introduction / discharge valve 58 is interposed in the middle of the suction / discharge path 56.
[0022]
The syringe for pure water 57 is composed of a hollow cylindrical cylinder 571 and a piston 572 inserted into the cylinder 571 and capable of sliding against the inner peripheral surface of the cylinder 571 while maintaining liquid tightness. Have been. The cylinder 571 has a suction / discharge port 571a at its tip, and the suction / discharge path 56 is connected to the suction / discharge port 571a. In the cylinder 571, the inner diameter of the hollow portion (the cross-sectional area when cut along a plane perpendicular to the sliding direction of the piston 572) is formed to be constant at each portion in the sliding direction of the piston 572.
[0023]
The piston 572 is reciprocated with respect to the cylinder 571 by a ball screw mechanism 59. In this embodiment, the pure water syringe 57 and the ball screw mechanism 59 constitute a pure water syringe mechanism. I have. The ball screw mechanism 59 includes a screw shaft 591 arranged along the sliding direction of the piston 572, a nut 592 screwed to the screw shaft 591, and a motor (for example, a stepping motor) for driving the screw shaft 591 to rotate. Motor or servomotor) M1. The rear end of the piston 572 (the portion protruding outside the cylinder 571) is connected to the nut 592. When the screw shaft 591 is rotated forward and reverse by the motor M1, the nut 592 is moved relative to the screw shaft 591. The piston 572 reciprocates with the cylinder 571 as the nut 592 reciprocates.
[0024]
In a state where pure water is present in the pure water introduction path 5 between the syringe upstream valve 54 and the syringe downstream valve 55, the screw shaft 591 is rotated by the motor M1 to pull out the piston 572 from the cylinder 571. By sliding, pure water existing in the pure water introduction path 5 can be sucked into the cylinder 571 through the suction / discharge path 56. Further, in a state where pure water is present in the cylinder 571, the screw shaft 591 is rotated by the motor M1 in a direction opposite to the direction in which pure water is sucked into the cylinder 571, and the piston 572 is pushed into the cylinder 571 (insertion). 2), the pure water in the cylinder 571 can flow into the pure water introduction path 5 through the suction / discharge path 56.
[0025]
On the other hand, the tip of a chemical solution introducing passage 6 extending from a chemical solution tank 61 storing HF (chemical solution) is connected to the chemical solution introducing valve 41 of the mixing valve 4. A nitrogen gas supply path 62 is connected to the chemical liquid tank 61, and a nitrogen gas (N ₂ ) Is supplied. Nitrogen gas is supplied to the chemical liquid tank 61 and the pressure in the chemical liquid tank 61 is increased, so that HF stored in the chemical liquid tank 61 is sent out onto the chemical liquid introduction path 6.
[0026]
A filter 63 for removing foreign matter in the HF flowing through the chemical solution introduction path 6 and a chemical solution tank side valve 64 for opening and closing the chemical solution introduction path 6 are arranged in the chemical solution introduction path 6 in order from the chemical solution tank 61 side. Is equipped. Further, one end of a suction / discharge path 65 is branched and connected to the chemical liquid introduction path 6 between the chemical liquid tank side valve 64 and the chemical liquid introduction valve 41, and the other end of the suction / discharge path 65 is connected to the chemical liquid. Connected to the syringe 66 for use.
[0027]
The syringe 66 for chemicals has the same configuration as the syringe 57 for pure water, and has a hollow cylindrical cylinder 661 and is inserted into the cylinder 661 to maintain liquid tightness with respect to the inner peripheral surface of the cylinder 661. And a slidable piston 662. The cylinder 661 has a suction / discharge port 661a at its tip, and the suction / discharge path 65 is connected to the suction / discharge port 661a. In the cylinder 661, the inner diameter of the hollow portion (the cross-sectional area when cut along a plane orthogonal to the sliding direction of the piston 662) is formed to be constant in each portion of the piston 662 in the sliding direction.
[0028]
The piston 662 is reciprocated with respect to the cylinder 661 by a ball screw mechanism 67. In this embodiment, the medical fluid syringe 66 and the ball screw mechanism 67 constitute a medical fluid syringe mechanism. The ball screw mechanism 67 includes a screw shaft 671 disposed along the sliding direction of the piston 662, a nut 672 screwed to the screw shaft 671, and a motor (for example, a stepping motor) for driving the screw shaft 671 to rotate. Motor or servomotor) M2. The rear end of the piston 662 (the portion protruding outside the cylinder 661) is connected to the nut 672. When the screw shaft 671 is rotated forward and reverse by the motor M2, the nut 672 moves with respect to the screw shaft 671. The piston 662 reciprocates with the cylinder 661 as the nut 672 reciprocates.
[0029]
In a state where HF is present in the chemical liquid introduction path 6 between the chemical liquid tank side valve 64 and the chemical liquid introduction valve 41, the screw shaft 671 is rotated by the motor M2, and the piston 662 is slid in a direction to pull out from the cylinder 661. By doing so, HF present in the chemical solution introduction path 6 can be sucked into the cylinder 661 through the suction / discharge path 65. Further, in a state where the HF thus sucked is present in the cylinder 661, the screw shaft 671 is rotated by the motor M2 in a direction opposite to the direction in which HF is sucked into the cylinder 661, and the piston 662 is pushed into the cylinder 661. , The HF in the cylinder 661 can flow into the chemical solution introduction path 6 through the suction / discharge path 65.
[0030]
FIG. 2 is a block diagram showing an electrical configuration of the substrate processing apparatus. The substrate processing apparatus further includes a control device 7 configured by, for example, a microcomputer.
The control device 7 includes, for example, a rotation drive mechanism 14, a motor M1, a motor M2, a chemical liquid introduction valve 41, 42, 43, 44, a syringe upstream valve 54, a syringe downstream valve 55, a syringe introduction / exit valve 58, and a chemical liquid tank. The side valve 64 and the like are connected as control targets. The control device 7 controls the operations of the rotation drive mechanism 14, the motor M1, and the motor M2 in accordance with a predetermined program for processing the wafer W, and also controls the chemical solution introduction valves 41, 42, 43, 44, and the syringe. The opening and closing of the upstream valve 54, the syringe downstream valve 55, the syringe introduction / exit valve 58, and the chemical liquid tank side valve 64 are controlled.
[0031]
FIG. 3 is a time chart for explaining processing of wafer W. In a period T1 to T2 before the wafer W to be processed is loaded, the chemical liquid introduction valves 41, 42, 43, and 44, the syringe upstream valve 54, the syringe downstream valve 55, the syringe introduction and discharge valve 58, and the chemical tank valve. 64 are all closed. Further, the rotation drive mechanism 14 is stopped, and the spin chuck 1 is stopped in a state where the wafer W can be set (held). Further, the motors M1 and M2 are also stopped, and the pure water syringe 57 and the chemical solution syringe 66 are in a state where the pistons 572 and 662 are inserted into the cylinders 571 and 661, respectively, as far as possible, and stopped. ing.
[0032]
From such a state, first, the syringe upstream side valve 54 and the syringe inlet / outlet valve 58 are opened, and the motor M1 is driven to move the piston 572 of the pure water syringe 57 at a constant speed in the direction of being pulled out from the cylinder 571. It is. At this time, the DIW supply source valve 51 or the HDIW supply source valve 52 is open, and the pure water supplied to the pure water introduction path 5 is supplied to the pure water introduction path by opening the syringe upstream valve 54. 5 flows between the syringe upstream valve 54 and the syringe downstream valve 55. Then, as the piston 572 moves, it is sucked into the cylinder 571 through the suction / discharge path 56.
[0033]
Further, the chemical liquid tank side valve 64 is opened, and the motor M2 is driven to move the piston 662 of the chemical liquid syringe 66 at a constant speed in a direction in which the piston 662 is pulled out of the cylinder 661. At this time, the nitrogen gas is supplied from the nitrogen gas supply path 62 to the chemical liquid tank 61, and the HF supplied to the chemical liquid introduction path 6 by opening the chemical liquid tank side valve 64 is suctioned / moved along with the movement of the piston 662. It is sucked into the cylinder 661 through the discharge path 65.
[0034]
The driving of the motors M1 and M2 is continued for a certain period T2 to T3. Thereby, the piston 572 of the syringe 57 for pure water and the piston 662 of the syringe 66 for chemical solution move by a certain amount, respectively, and the cylinder 571 of the syringe 57 for pure water and the cylinder 661 of the syringe 66 for chemical solution respectively move a certain amount. DIW and HF are sucked up.
When the motors M1 and M2 are stopped, the syringe inlet / outlet valve 58 and the chemical liquid tank side valve 64 are closed, while the syringe downstream valve 55 is opened. At this time, the DIW supply valve 51 or HDIW supply valve 52 and the syringe upstream valve 54 remain open. Therefore, when the syringe downstream valve 55 is opened, the pure water flowing through the pure water introduction passage 5 is discharged from the nozzle 2 through the mixing valve 4 and the mixed liquid supply passage 3. By discharging pure water from the nozzle 2 before carrying in the wafer W to be processed, the inside of the nozzle 2, the mixed liquid supply path 3, the mixing valve 4, and the like (the part through which DHF and pure water flow) are discharged. It can be washed with pure water.
[0035]
When the pure water is discharged from the nozzle 2 over a period T3 to T4, the syringe upstream valve 54 and the syringe downstream valve 55 are closed, and the processing of the processing target is performed in a state in which the posture for receiving the wafer W is prepared. It is waited for the wafer W to be carried in. The wafer W to be processed is then carried in by a transfer robot (not shown), and is transferred from the transfer robot to the spin chuck 1 and set.
[0036]
When a period T5 to T6 elapses after the wafer W to be processed is set on the spin chuck 1, the rotation driving mechanism 14 is driven, and the wafer W held on the spin chuck 1 is rotated at a predetermined speed. Further, the syringe upstream valve 54 and the syringe downstream valve 55 are opened. At this time, the DIW supply source valve 51 or the HDIW supply source valve 52 is open, and the pure water supplied to the pure water introduction path 5 via the DIW supply source valve 51 is supplied to the syringe upstream valve 54 and the syringe downstream side. When the valve 55 is open, it flows into the mixing valve 4 from the pure water introduction path 5 and is further supplied to the nozzle 2 through the mixed liquid supply path 3. As a result, pure water is supplied from the nozzle 2 to the surface of the rotating wafer W, and the surface of the wafer W is wetted with pure water (pre-wet) prior to DHF processing. The supply of pure water to the surface of the wafer W is continued for a predetermined period T6 to T7.
[0037]
Thereafter, the syringe upstream valve 54 is closed while the syringe downstream valve 55 is open, while the syringe introduction / exhaust valve 58 and the drug solution introduction valve 41 are opened. Further, the motors M1 and M2 are driven, and the piston 572 of the pure water syringe 57 and the piston 662 of the chemical solution syringe 66 are moved in the directions of being pushed into the cylinders 571 and 661, respectively. The moving speed of the pistons 572 and 662 at this time is a constant speed such that the pistons 572 and 662 are inserted into the cylinders 571 and 661 as far as possible after a predetermined period T7 to T8 elapses. It is. Therefore, the movement of the pistons 572 and 662 causes the pure water in the pure water syringe 57 to be sent out to the pure water introduction path 5 at a constant flow rate, and the HF in the chemical solution syringe 66 to enter the chemical liquid introduction path 6 at a constant flow rate. Will be sent out. Pure water and HF sent out at a constant flow rate to the pure water introduction path 5 and the chemical solution introduction path 6, respectively, flow into the mixing valve 4, are mixed in the mixing valve 4, become DHF, and pass through the mixed liquid supply path 3. The wafer W is supplied to the nozzle 2 and supplied from the nozzle 2 to the surface of the rotating wafer W.
[0038]
Since pure water and HF are supplied to the mixing valve 4 at a constant flow rate, respectively, the mixing ratio of HF and pure water (for example, HF: The inner diameter (cross-sectional area) of the cylinder 571 of the syringe 57 for pure water and the cylinder 661 of the syringe 66 for chemical solution is designed so as to correspond to (pure water = 1: 200), and the piston 572 of the syringe 57 for pure water is designed. If the moving speed of the piston 662 of the syringe 66 for chemicals is determined, the mixing ratio of HF and pure water in the mixing valve 4 is always kept constant. Therefore, DHF in which HF and pure water are mixed at a constant mixing ratio can be supplied to the surface of the wafer W at a constant flow rate over the period T7 to T8, thereby causing processing defects such as insufficient cleaning. Thus, a favorable process using DHF can be performed on the surface of the wafer W.
[0039]
When the processing by DHF on the surface of the wafer W is performed for the period T7 to T8, the motors M1 and M2 are stopped, and the syringe introduction / exit valve 58 and the chemical solution introduction valve 41 are closed. At the same time, the syringe upstream side valve 54 is opened. At this time, the DIW supply valve 51 or the HDIW supply valve 52 and the syringe downstream valve 55 remain open. Therefore, when the syringe upstream valve 54 is opened, the pure water flowing through the pure water introduction path 5 is supplied to the nozzle 2 through the mixing valve 4 and the mixed liquid supply path 3, and the pure water flowing from the nozzle 2 Supplied to the surface. By supplying the pure water to the surface of the wafer W, DHF attached to the surface of the wafer W is washed away by the pure water.
[0040]
When the wafer W is washed with pure water for the period T8 to T9, the syringe upstream valve 54 and the syringe downstream valve 55 are closed, and the supply of the pure water from the nozzle 2 to the surface of the wafer W is stopped. . Thereafter, the rotation speed of the wafer W by the spin chuck 1 is increased to a predetermined high rotation speed (for example, 3000 rpm), and the pure water adhering to the surface of the washed wafer W is shaken off by centrifugal force and dried. Is performed. This drying process is performed for a predetermined period 9 to T10. When the drying process is completed, the rotation of the wafer W by the spin chuck 1 is stopped, and thereafter, at a timing when a predetermined period T10 to T11 elapses, the processed wafer W is unloaded from the spin chuck 1 by the transfer robot. .
[0041]
As described above, according to the substrate processing apparatus of this embodiment, DHF produced by mixing HF and pure water at a constant mixing ratio is supplied to the surface of the wafer W at a constant flow rate. In addition, the surface of the wafer W can be favorably processed by DHF without causing processing defects such as insufficient cleaning.
In order to allow pure water and HF to flow into the mixing valve 4 at a constant flow rate, the flow rates are adjusted to the middle portions of the pure water introduction path 5 and the chemical solution introduction path 6 without using the pure water syringe 57 and the chemical solution syringe 66, respectively. It is conceivable that a valve is interposed, and the flow rate of the pure water and the HF flowing through the pure water introduction path 5 and the chemical solution introduction path 6, respectively, is controlled by the flow control valve. However, in the configuration using the flow rate adjusting valve, the flow rate cannot be controlled as accurately as the configuration using the pure water syringe 57 and the chemical solution syringe 66. When the flow pressure of HF fluctuates, the mixing ratio of HF and pure water in the mixing valve 4 may fluctuate. On the other hand, in the configuration according to the present embodiment, pure water and HF for producing DHF are sent out from the pure water syringe 57 and the chemical solution syringe 66, respectively. Even if the flow pressure of HF sent to the mixing valve 4 fluctuates, there is no possibility that the mixing ratio of HF and pure water in the mixing valve 4 fluctuates.
[0042]
Although the chemical solution (HF) and the pure water are mixed while being sent out at a constant flow rate by the pure water syringe 57 and the chemical solution syringe 66, respectively, the present invention is not limited to this. The syringe 57 or 66 may be applied to only one of them. In such a case, it is particularly effective to apply the syringe 66 to HF having a small mixing ratio.
In this embodiment, a chemical (HF) and pure water are mixed by a mixing valve 4 to form a mixed liquid (DHF), and the mixed liquid created by the mixing valve 4 is applied from the nozzle 2 to the surface of the wafer W. The supply configuration has been described, but the chemical solution and the pure water delivered at a constant flow rate from the pure water syringe 57 and the chemical solution syringe 66 are mixed on or near the surface of the wafer W, respectively. A configuration in which a mixed solution of a chemical solution and pure water is created near the surface may be employed. Further, a configuration may be adopted in which a chemical solution and pure water are mixed in a nozzle to form a mixed solution, and the mixed solution created in the nozzle is supplied to the surface of the wafer W.
[0043]
FIG. 4 is a diagram showing a simplified configuration for creating a mixed solution of a chemical solution and pure water near the surface of the wafer W. In FIG. 4, parts corresponding to the respective parts shown in FIG. 1 are denoted by the same reference numerals as in FIG. Further, the description of the parts denoted by the same reference numerals will be omitted.
A filter 8 for removing foreign matter in the pure water flowing through the pure water introduction passage 5 is provided downstream of the syringe downstream valve 55 with respect to the flow direction of the pure water (DIW or HDIW). Is equipped. The tip of the pure water introduction path 5 is connected to a nozzle 20 for supplying a chemical solution and pure water to the surface of the wafer W held by the spin chuck 1. Further, for example, the tips of four chemical solution introduction paths 6 through which various chemical solutions flow are connected to the nozzle 20. In the four chemical liquid introduction paths 6, chemical liquid introduction valves 41, 42, 43, and 44 are respectively provided downstream of the branch point of the suction / discharge path 65 in the chemical liquid flow direction. In addition, four sets of components on the upstream side of the chemical solution introduction valves 41, 42, 43, and 44 from the chemical solution syringe 66 shown in FIG. .
[0044]
As shown in FIG. 5, the nozzle 20 has discharge ports 21, 22, 23, 24, and 25 for discharging pure water and various chemicals supplied from the pure water introduction path 5 and the respective chemical liquid introduction paths 6. ing. On the lower surface of the nozzle 20, for example, a discharge port 21 for discharging pure water supplied from the pure water introduction path 5 toward the surface of the wafer W has a large opening at the center, and Around the discharge port 21, discharge ports 22 to 25 for discharging various chemicals supplied from the respective chemical liquid introduction paths 6 toward the surface of the wafer W are opened at substantially equal intervals. The discharge ports 21 to 25 are such that pure water discharged from the discharge port 21 and the chemical solution discharged from the discharge ports 22 to 25 are mixed (in the vicinity of the surface of the wafer W) before reaching the surface of the wafer W. Is formed in the vicinity of
[0045]
According to this configuration, the piston 572 of the syringe for pure water 57 and the pistons 662 of the four syringes for chemical liquid 66 are respectively moved at a constant speed, and the pure water and the chemical liquid are supplied to the pure water introduction path 5 and the chemical liquid introduction path 6, respectively. By sending the mixture at a flow rate, a mixed liquid in which the chemical liquid and the pure water are mixed at a constant mixing ratio can be supplied to the surface of the wafer W. Therefore, the surface of the wafer W can be favorably treated with the mixed liquid without causing a processing failure such as insufficient cleaning.
[0046]
When the interval between the discharge ports 21 to 25 is large, the pure water discharged from the discharge port 21 and the chemical liquid discharged from the discharge ports 22 to 25 are supplied to the surface of the wafer W without being mixed with each other, The mixture mixes on the surface of the wafer W to form a mixture. Even in this case, the piston 572 of the pure water syringe 57 and the pistons 662 of the four chemical liquid syringes 66 are respectively moved at a constant speed, so that the pure water and the chemical liquid are supplied to the pure water introduction path 5 and the chemical liquid introduction path 6, respectively. By sending out at a constant flow rate, pure water and a chemical solution can be respectively supplied at a constant flow rate onto the surface of the wafer W, and a mixed solution obtained by mixing the chemical solution and the pure water at a constant mixing ratio on the surface of the wafer W Can be created. Therefore, the surface of the wafer W can be favorably treated with the mixed liquid without causing a processing failure such as insufficient cleaning. In this embodiment, four systems of the chemical solution introduction path 6 are provided, but the number may be appropriately increased or decreased according to the type of the mixed chemical solution, and at least one system may be provided.
[0047]
FIG. 6 is a diagram for explaining a configuration of a nozzle for mixing a chemical solution and pure water to form a mixed solution and supplying the mixed solution to the surface of the wafer W. The nozzle 200 shown in FIG. 6 can be used in place of the nozzle 20 provided in the substrate processing apparatus shown in FIG.
The nozzle 200 mixes the communication paths 201, 202, 203, 204, and 205 communicating with the pure water introduction path 5 and the four chemical introduction paths 6, respectively, and the pure water and the chemical solution flowing through these communication paths 201 to 205 ( The mixing path 206 has a discharge path 207 for discharging the mixed liquid obtained by mixing the pure water and the chemical in the mixing path 206 toward the surface of the wafer W.
[0048]
The nozzle 200 is used in place of the nozzle 20 shown in FIG. 4, and pure water and a chemical solution delivered at a constant flow rate from the pure water syringe 57 and the chemical solution syringe 66 are supplied to the nozzle 200, respectively. A mixed solution in which the chemical solution and pure water are mixed at a fixed mixing ratio can be prepared, and the prepared mixed solution can be supplied to the surface of the wafer W at a constant flow rate. Therefore, even with the configuration employing the nozzle 200, it is possible to perform a favorable process using the mixed liquid on the surface of the wafer W without causing processing defects such as insufficient cleaning.
[0049]
While some embodiments of the present invention have been described above, the present invention can be embodied in other forms. For example, in the above embodiment, the wafer W is taken as an example of a substrate to be processed. However, the present invention is not limited to the wafer W, and a glass substrate for a liquid crystal display device, a glass substrate for a plasma display panel, a glass substrate for a photomask, Other types of substrates, such as magnetic / optical disk substrates, may be processed.
[0050]
In addition, various design changes can be made within the scope of the matters described in the claims.
[Brief description of the drawings]
FIG. 1 is a diagram showing a simplified configuration of a substrate processing apparatus according to an embodiment of the present invention.
FIG. 2 is a block diagram illustrating an electrical configuration of the substrate processing apparatus.
FIG. 3 is a time chart for explaining substrate processing in the substrate processing apparatus.
FIG. 4 is a diagram showing a simplified configuration for creating a mixed solution of a chemical solution and pure water on the surface of a substrate.
5 is a view of a nozzle provided in the substrate processing apparatus having the configuration shown in FIG. 4, as viewed from below.
FIG. 6 is a diagram for explaining a configuration of a nozzle for preparing a mixed solution by mixing a chemical solution and pure water, and supplying the mixed solution to a surface of a substrate.
FIG. 7 is a diagram showing a simplified configuration of a conventional substrate processing apparatus.
[Explanation of symbols]
1 Spin chuck
2 nozzles
3 Mixed liquid supply path
4 Mixing valve
5 Pure water introduction route
6 Chemical solution introduction path
7 Control device
56 Suction / discharge path
57 Syringe for pure water
571 cylinder
572 piston
59 Ball screw mechanism
591 screw shaft
592 nut
M1 motor
65 Suction / discharge path
66 Syringe for chemicals
661 cylinder
662 piston
67 Ball screw mechanism
671 Screw shaft
672 nut
M2 motor
W wafer
20 nozzles
21-25 outlet
200 nozzles

Claims (6)

A substrate processing apparatus for performing processing by supplying a mixed liquid of a first processing liquid and a second processing liquid to a substrate,
Substrate rotating means for rotating while holding the substrate,
A nozzle for supplying a mixed liquid of the first processing liquid and the second processing liquid to the substrate rotated by the substrate rotating means;
A first processing liquid supply passage through which the first processing liquid supplied to the nozzle flows;
A second processing liquid supply passage through which a second processing liquid supplied toward the nozzle flows,
A substrate processing apparatus, comprising: a first processing liquid syringe connected to the first processing liquid supply path for sending out the first processing liquid to the first processing liquid supply path. 2. The substrate processing apparatus according to claim 1, further comprising a second processing liquid syringe connected to the second processing liquid supply path for sending out the second processing liquid to the second processing liquid supply path. apparatus. Each end of the first processing liquid supply path and the second processing liquid supply path is connected, and a first processing liquid flowing from the first processing liquid supply path and a second processing liquid flowing from the second processing liquid supply path. 3. The substrate processing apparatus according to claim 1, further comprising a merging flow path for merging the processing liquid and supplying a mixed liquid of the first processing liquid and the second processing liquid to the nozzle. 4. The nozzle is connected to each end of the first processing liquid supply path and the second processing liquid supply path, and is connected to the first processing liquid flowing from the first processing liquid supply path and the second processing liquid supply path. The substrate processing apparatus according to claim 1, further comprising a plurality of discharge ports for discharging the inflowing second processing liquid toward the substrate. 4. The nozzle is connected to each end of the first processing liquid supply path and the second processing liquid supply path, and is connected to the first processing liquid flowing from the first processing liquid supply path and the second processing liquid supply path. 3. The substrate according to claim 1, wherein the inflowing second processing liquid is merged inside, and a mixed liquid of the first processing liquid and the second processing liquid is discharged toward the substrate. Processing equipment. A method of processing a substrate using a mixture of a first processing liquid and a second processing liquid,
Rotating the substrate to be processed while holding it by the substrate rotating means;
Sending the first processing liquid from the first processing liquid syringe to the first processing liquid supply path;
Sending the second processing liquid to the second processing liquid supply path;
Combining and mixing the first processing liquid flowing through the first processing liquid supply path and the second processing liquid flowing through the second processing liquid supply path;
Supplying a mixed liquid of a first processing liquid and a second processing liquid to the substrate rotated by the substrate rotating means.

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