JP2006080547A - Processor and processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a processor capable of determining the optimal time for filling up with a treatment undiluted solution, stabilizing and assuring the component ratio and the amount of a treatment liquid, and suppressing the amount of the consumption of the treatment liquid to the minimum. <P>SOLUTION: In a processor for filling up a reservoir tank 30 with a plurality of treatment undiluted solutions at a predetermined proportion, supplying a treatment liquid in the reservoir tank 30 to a substrate W, and carrying out a process, a supplement arrangement 40 for filling up the reservoir tank 30 with the treatment undiluted solutions is provided correspondingly to the number of the sheets of the process and the processing time of the substrate W, and the treatment liquid produced by mixing the treatment undiluted solutions is supplied to the substrate W. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a processing apparatus and a processing method for processing a substrate such as a semiconductor wafer or a glass plate for LCD with a processing liquid.

  In general, in a semiconductor device manufacturing process, a cleaning processing system is used to remove contamination such as particle organic contaminants and metal impurities adhering to the surface of a semiconductor wafer (hereinafter referred to as “wafer”), for example. ing. As one of the systems for cleaning a wafer, a cleaning processing system using a single wafer processing apparatus is known.

The processing apparatus of this cleaning processing system includes a container for storing a wafer, a rotary table for rotatably holding the wafer in the container, a supply nozzle for supplying a processing liquid such as a chemical solution or pure water to the front and back surfaces of the wafer, , A storage tank for storing a processing solution such as a chemical solution or pure water is provided. In the wafer cleaning process performed in such a processing apparatus, the wafer is held on a rotary table and rotated in the container. Then, the processing liquid previously stored in the storage tank is supplied from the supply nozzle to the surface of the rotating wafer to perform a cleaning process to remove particles, organic contaminants, and the like attached to the surface of the wafer. Thereafter, a rinsing process is performed with pure water, and a drying gas such as N ₂ gas is supplied to perform the drying process.

In addition, as the processing liquid, an APM processing liquid in which an aqueous solution of ammonia (NH ₄ OH), a hydrogen peroxide solution (H ₂ O ₂ ), and pure water (H ₂ O) are mixed, hydrofluoric acid (HF), A DHF treatment liquid mixed with pure water is known.

  By the way, in order to perform the wafer cleaning process well, it is important that the processing liquid is stored in a certain liquid amount. However, in the conventional processing apparatus, the timing for replenishing the processing stock solution is not particularly determined. For this reason, a situation may occur where the amount of the processing liquid in the storage tank becomes insufficient as the cleaning process proceeds. It is also important that the component ratio of the processing liquid is kept constant. However, for example, in an APM treatment liquid containing highly volatile ammonia, the concentration of ammonia in the APM treatment liquid is reduced by evaporation, and the component ratio of the APM treatment liquid collapses. There were problems such as a decline.

  Furthermore, in the conventional processing apparatus, the processing liquid used for the cleaning process is naturally drained out of the container through a drain line provided at the bottom of the container, and discarded for one-time use. It was. However, discarding the processing liquid for each cleaning process of a single wafer results in a huge consumption of the processing liquid. For this reason, there are various points to be improved, such as the cost of the processing solution soaring, and the time and effort required to manage the large amount of disposal of the chemical solution.

  Accordingly, the present invention has been made in view of the above-mentioned problems, and its object is to determine an optimum time for replenishing the processing stock solution and to stably ensure the component ratio and the liquid amount of the processing liquid. At the same time, it is to provide a processing apparatus capable of minimizing the consumption of the processing liquid.

  In order to solve the above-described problems, the present invention provides a processing apparatus for replenishing a storage tank with a plurality of processing stock solutions at a predetermined rate, supplying the processing liquid in the storage tank to the substrate, and processing the substrate. A replenishment mechanism is provided for replenishing the processing stock solution to the storage tank in accordance with the number of processing and the processing time, and the processing solution generated by mixing the processing stock solution is supplied to the substrate.

  According to this configuration, the replenishment mechanism replenishes the storage tank with a plurality of processing stock solutions corresponding to the number of substrates to be processed and the processing time, and mixes these processing stock solutions. Thereby, in the storage tank, the component ratio and the liquid amount of the processing liquid can be stably secured so as not to hinder the processing. Further, the timing of replenishing the processing stock solution may be obtained in advance by experiments or the like using the number of processed substrates and the processing time as a guide. In this way, since the optimum time for replenishing the processing stock solution is determined, a measuring device such as a concentration sensor is not required.

  The present invention also provides a processing apparatus for replenishing a storage tank with a plurality of processing stock solutions at a predetermined ratio, supplying the processing liquid in the storage tank to the substrate and processing the substrate, integrating the processing time of the substrate, A replenishment mechanism is provided for replenishing the processing stock solution from the replenishment mechanism to the storage tank every time the treated processing time reaches a predetermined time, and the processing liquid generated by mixing the processing stock solution is supplied to the substrate. .

  In these processing apparatuses, the replenishment mechanism is configured to replenish a plurality of processing stock solutions into the storage tank, and continuously replenishes the storage tank with at least one processing stock solution at a predetermined time. At least one of the plurality of processing stock solutions may be intermittently replenished several times to replenish the storage tank. According to such a configuration, for example, a processing stock solution such as pure water is continuously replenished to the storage tank without interruption, while a processing stock solution mainly composed of chemical components that affect processing is supplied to a predetermined tank. Instead of replenishing the storage tank all at once, the storage tank is intermittently replenished several times. Thereby, in the processing liquid in the storage tank, such a processing stock solution component is maintained at a predetermined concentration without causing a rapid concentration change.

  It is preferable to include a holding unit that rotatably holds the substrate and a supply unit that supplies the processing liquid to the substrate held by the holding unit. According to such a configuration, the replenishment mechanism is utilized in a so-called single wafer processing apparatus that supplies the processing liquid to the substrate held by the holding means for processing.

  A recovery circuit that recovers the processing liquid that has processed the substrate to the storage tank; an adjustment circuit that adjusts the processing liquid in the storage tank; and a supply circuit that supplies the processing liquid in the storage tank to the substrate. It is preferable to arrange a gas-liquid separation mechanism in the middle of the recovery circuit. According to such a configuration, the processing liquid used for the processing is recovered in the storage tank via the recovery circuit, and cleaning, temperature control, and the like are performed in the adjustment circuit. The processing liquid thus adjusted is supplied to the substrate by the supply circuit and reused for processing.

  According to the present invention, in the processing method of supplying the processing liquid stored in the storage tank to the substrate, the storage tank is replenished with the processing stock solution corresponding to the number of processed substrates and the processing time. A processing solution generated by mixing the processing stock solution replenished to the substrate is supplied to the substrate.

  When replenishing the storage tank with a plurality of processing stock solutions, at least one processing stock solution is continuously replenished to the storage tank, and at least one processing stock solution of the remaining plurality of processing stock solutions is added every predetermined time. The storage tank may be replenished intermittently several times.

  In the processing method of supplying the processing liquid stored in the storage tank to the substrate, the processing time of the substrate is integrated, and the processing stock solution is replenished to the storage tank every time the integrated processing time reaches a predetermined time. A processing method is provided.

  According to this method, since the processing time of the substrate is integrated and the processing stock solution is replenished every time the integrated processing time reaches a predetermined time, the processing time is reduced even if the processing time per substrate changes. Correspondingly, the processing stock solution can be periodically replenished in the storage tank. Therefore, the component ratio and the liquid amount of the processing liquid can be secured stably.

  When the stock solution is replenished to the storage tank, it may be replenished with a predetermined liquid amount. Further, the processing liquid that has processed the substrate may be collected in the storage tank.

  According to the present invention, since the replenishment mechanism for replenishing the storage stock solution to the storage tank according to the number of processed substrates and the processing time is provided, it is possible to stably secure the component ratio and the liquid amount of the processing liquid. it can. Therefore, it is possible to continue good processing. In addition, a measuring device such as a concentration sensor is not necessary, and the processing apparatus can be simplified. As a result, for example, productivity in the manufacture of semiconductor devices can be improved.

  According to the present invention, it is possible to keep the processing stock solution components that affect the processing at a predetermined concentration in the processing solution. Further, the replenishment mechanism can be utilized for a single wafer processing apparatus. Further, by reusing the treatment liquid, the consumption of the treatment liquid can be minimized. Therefore, it is excellent in management concerning the processing liquid such as disposal.

  The method of the present invention can be suitably applied to a processing apparatus. In addition, the processing time per substrate can be flexibly dealt with, and the component ratio and the liquid amount of the processing liquid can be secured stably.

  Hereinafter, a preferred embodiment of the present invention will be described based on a cleaning processing system configured to carry in wafers by carrier, clean and dry wafers one by one, and carry out wafers by carrier. . FIG. 1 is a plan view of a cleaning processing system 1 for explaining the present embodiment.

  The cleaning processing system 1 includes a placement unit 2 on which a carrier C that stores wafers W is placed, and wafers W before the processing step are taken out one by one from the carrier C placed on the placement unit 2 and processed. Cleaning provided with the transfer arm 3 for storing the wafers W after the process one by one in the carrier C, and the processing devices 6 to 11 according to the present embodiment for performing predetermined cleaning processing and drying processing on the wafer W A processing unit 4 and a chemical box 15 disposed on the back side of the cleaning processing unit 4 with a maintenance space 14 interposed therebetween are provided.

  The placement unit 2 is configured to be able to place a plurality of carriers C that contain 25 wafers. The transfer arm 3 is configured to be movable in the horizontal and vertical (X, Y, Z) directions and to be rotatable (θ direction) about the vertical axis. The cleaning unit 4 includes a transfer arm 12 having the same configuration as the transfer arm 3 that transfers the wafer W, and a wafer transfer table that plays a role of transferring the wafer W between the transfer arm 3 and the transfer arm 12. 13 is provided. The processing devices 6, 7, and 8 are arranged so as to surround three of the four sides of the transfer arm 12, and a casing 16 that houses a distribution board of the electric system is arranged on the other side of the transfer arm 12. Has been. Below the processing devices 6 to 8, the processing devices 9, 10, and 11 are arranged in the same manner as the processing devices 6 to 8, and the processing devices 6 to 8 and the processing devices 9 to 11 can simultaneously perform the cleaning process. ing.

For example, a typical cleaning process performed in the processing apparatuses 6 to 8 and 9 to 11 will be described. In the processing apparatuses 6 and 9, an APM processing liquid (NH ₄ OH / H ₂ O ₂ / H ₂ mainly composed of ammonia) is used. SC1 cleaning using a mixed solution of O) is performed to remove impurities such as organic contaminants and particles adhering to the surface of the wafer W, and rinse treatment with pure water is performed. Then, in the processing apparatuses 7 and 10, DHF cleaning using a DHF processing liquid (HF / H ₂ O mixed liquid) mainly composed of hydrofluoric acid is performed to remove an oxide film or the like formed on the surface of the wafer W. Then, rinse with pure water. In the processing apparatuses 8 and 11, SC2 cleaning is performed using an HPM processing liquid (HCl / H ₂ O ₂ / H ₂ O mixed liquid) mainly composed of hydrochloric acid to remove metal ions, and pure water is used. Perform rinsing.

  The above arrangement and the combination of these processing apparatuses can be arbitrarily combined depending on the type of cleaning process for the wafer W. For example, some processing devices may be reduced, or conversely, other processing devices may be added.

  Next, the configuration of each processing apparatus 6, 8, 9, 11 will be described. Since each of the processing devices 6, 8, 9, and 11 has the same configuration, the SC1 cleaning is performed using an APM processing solution that is a mixture of processing stock solutions such as an aqueous ammonia solution, a hydrogen peroxide solution, and pure water. The processing apparatus 6 to be performed will be described as a representative.

  FIG. 2 is a schematic cross-sectional view of the processing apparatus 6. In the container 20 provided in the processing apparatus 6, a rotary table 23 connected to the upper end of the lifting / lowering rotating shaft 22 of the lifting / lowering rotating mechanism 21 is provided. A supply nozzle 24 for supplying pure water or the like to the back surface of the wafer W is provided on the upper surface of the rotary table 23, and the supply nozzle 24 has a process penetrating through the centers of the rotary table 23 and the lifting / lowering rotary shaft 22. A liquid supply path 25 is connected.

Further, a holding member 26 is disposed on the upper surface of the turntable 23 so that the wafer W can be held in a state of being floated above the turntable 23. A movable supply nozzle 27 for supplying APM processing liquid or pure water to the surface of the wafer W accommodated in the container 20 and supplying a dry gas such as N ₂ gas is provided above the container 20. Yes. Further, the APM processing liquid shaken off from the back surface of the wafer W by the rotation of the wafer W is drained through a drainage conduit 28 provided at the bottom of the container 20. In addition, since the processing devices 8, 9, and 11 have the same configuration as the processing device 6, detailed description thereof is omitted.

  Since the same processing liquid is used in each of the processing apparatuses 6 and 9 and the processing apparatuses 8 and 11, a circuit related to the processing liquid is shared. Since these circuits all have the same configuration, the processing apparatuses 6 and 9 using the APM processing liquid will be described as representatives.

  As shown in FIG. 3, the processing apparatuses 6 and 9 are provided with a storage tank 30 for storing the APM processing liquid. Further, the processing apparatus 6 includes a recovery circuit 31 that recovers the APM processing liquid obtained by SC1 cleaning the wafer W to the storage tank 30, an adjustment circuit 32 that adjusts the state of the APM processing liquid in the storage tank 30, and the storage tank 30. And a supply circuit 33 for supplying the APM processing liquid in the wafer W to the wafer W. The supply nozzle 27 is connected to a pure water supply circuit 35 having a valve 34 for supplying pure water. The processing device 9 has the same circuit configuration as that of the processing device 6 except that the recovery circuit 31 ′ is connected to the recovery circuit 31 to be merged. Are denoted by the same reference numerals, and redundant description is omitted.

  Here, a replenishment mechanism 40 for replenishing the storage tank 30 with an aqueous ammonia solution, a hydrogen peroxide solution, and pure water is provided above the storage tank 30. The replenishment mechanism 40 includes an ammonia replenishment system 43 including a tank 41 and a pump 42 that store an aqueous ammonia solution adjusted to a predetermined concentration, and a tank that stores a hydrogen peroxide solution similarly adjusted to a predetermined concentration. And a pure water replenishment system 49 in which a valve 48 is arranged in a pure water supply circuit 47. Furthermore, the controller 50 which controls the operation rate of the pumps 42 and 45 and the opening degree of the valve 48 is provided. In this manner, the controller 50 appropriately controls the operating rates of the pumps 42 and 45 and the opening of the valve 48 to replenish the storage tank 30 with a predetermined amount of aqueous ammonia solution, hydrogen peroxide solution, and pure water, These are mixed to generate an APM treatment liquid having a predetermined component ratio in the storage tank 30.

  The replenishing mechanism 40 replenishes the storage tank 30 with an aqueous ammonia solution, a hydrogen peroxide solution, and pure water according to the number of wafers W processed and the cleaning time. That is, in the normal SC1 cleaning, when the APM processing liquid used for the SC1 cleaning is recovered as described later, the APM processing liquid cannot be completely recovered in the storage tank 30. In the APM processing liquid mainly composed of highly volatile ammonia, the ammonia evaporates as the SC1 cleaning of the wafer W progresses. As a result, the concentration of ammonia in the APM treatment liquid decreases. Similarly, the concentration of hydrogen peroxide in the APM treatment liquid also decreases. In addition, when shifting from the SC1 cleaning to the rinsing process, a considerable amount of the APM processing liquid remaining in the container 20 is washed away with pure water, so that the amount of the APM processing liquid gradually decreases. It has become.

  Therefore, the ratio of decrease in the concentration of ammonia and hydrogen peroxide in the APM processing solution and the amount of the APM processing solution as the number of processed wafers W is increased and the cleaning time is increased based on the experimental data performed in advance. Based on this, the timing for replenishing the ammonia aqueous solution, the hydrogen peroxide solution, and the pure water, and the amount of liquid are calculated and stored in the controller 50 in advance. Specifically, the total amount of ammonia aqueous solution, hydrogen peroxide solution, and pure water to be replenished is determined by the recovery rate of the APM treatment solution, and the concentration reduction rate of ammonia and hydrogen peroxide in the APM treatment solution is determined by The ratio of each of the aqueous ammonia solution, hydrogen peroxide solution, and pure water to be replenished is determined.

  When the predetermined time comes, the controller 50 transmits an operation signal to the pumps 42 and 45 and the valve 48 so that the aqueous ammonia solution, the hydrogen peroxide solution, and the pure water are replenished to the storage tank 30 with a predetermined liquid amount, respectively. It has become. As described above, the stability of the APM treatment liquid against the change in the component ratio and the liquid amount is ensured by using two measures of the number of treatments and the washing time for the replenishment timing of the aqueous ammonia solution, hydrogen peroxide solution, and pure water. . In addition, since the optimal time for replenishment is determined in advance, a concentration sensor, a liquid amount sensor, or the like for measuring a change in the APM processing liquid during the SC1 cleaning becomes unnecessary.

  Further, the recovery circuit 31 is connected to the drainage conduit 28 of the processing device 6, and the outlet thereof is connected to the storage tank 30 disposed below the container 20. In the middle of the recovery circuit 31, a gas-liquid separation mechanism 52 and a drain circuit 53 are arranged in order from the top, and the drain circuit 53 is connected to the recovery circuit 31 via a three-way valve.

  As shown in FIG. 4, in this gas-liquid separation mechanism 52, the APM processing liquid flowing in from the inflow port 55 flows out from the outflow port 56. Further, the exhaust port 57 is provided above, the partition plate 58 is suspended from the ceiling, and the mesh-shaped rectifying plate 60 having a plurality of small holes 59 is horizontally arranged so as to partition the inside of the gas-liquid separation mechanism 52 vertically. In addition, an inclined table 61 whose upper surface is inclined toward the outlet 56 is provided at the bottom. The gas-liquid separation mechanism 52 is mixed into the APM processing liquid while the APM processing liquid flows in from the drainage pipe 28 through the inlet 55 and flows along the inclined base 61 toward the outlet 56. Air bubbles are removed, and the APM treatment liquid is not allowed to flow out from the exhaust port 57. The bubbles removed from the liquid do not flow backward to the inflow port 55 by the partition plate 58 but are exhausted from the exhaust port 57 while being adjusted by the rectifying plate 60.

  The pure water supplied to the supply nozzle 27 by the pure water supply circuit 35 and used for the rinsing process is drained from the drain circuit 53 by the switching operation of the three-way valve 54 after passing through the gas-liquid separation mechanism 52 and is stored in the storage tank 30. In addition, APM processing liquid can be stored.

  The inlet of the adjustment circuit 32 is connected to the bottom of the storage tank 30, and a pump 65, a damper 66, a heater 67, and a filter 68 are arranged along the flow of the APM processing liquid from the upstream side in the middle of the adjustment circuit 32. It is connected to the upper part of the storage tank 30. Then, by operating the pump 65, the APM treatment liquid is caused to flow into the adjustment circuit 32 from below the storage tank 30, adjusted to a predetermined temperature by the heater 67, and impurities in the APM treatment liquid are removed by the filter 68, and then again. The APM processing liquid is introduced from above the storage tank 30 and circulated for adjustment.

  The supply circuit 33 is connected between the adjustment circuit 32 and the supply nozzle 27 via a valve 70. In the middle of the supply circuit 33, the processing liquid supply path 25 having the three-way valve 72 connected to the pure water supply circuit 71, and a valve for operating whether to supply the APM processing liquid to the supply nozzle 27 by opening and closing. 73 is arranged. If the three-way valve 72 and the valve 73 are opened after the valve 70 is opened, the APM processing liquid flows into the supply circuit 33 without circulating through the adjustment circuit 32, and the supply nozzles 27 and 24 cover the front and back surfaces of the wafer W. SC1 cleaning is possible. In this way, at times other than SC1 cleaning, the valve 70 is closed and the APM processing liquid is circulated and adjusted by the adjustment circuit 32. At SC1 cleaning, the APM cleaning liquid in the storage tank 30 is recovered by the adjustment circuit 32, the supply circuit 33, and the recovery circuit. The APM processing liquid is circulated in the order of the circuit 31 to be reused, and the consumption of the APM processing liquid is saved.

  In addition, since the circuit configuration concerning the processing devices 8 and 11 has the same configuration, detailed description thereof is omitted.

  Next, a cleaning process for the wafer W performed in the cleaning system 1 configured as described above will be described. First, a carrier C that stores, for example, 25 wafers W that have not been cleaned by a transfer robot (not shown) is placed on the placement unit 2. Then, the wafers W are taken out one by one from the carrier C placed on the placement unit 2 and transferred from the carry-in arm 3 to the transfer arm 12 via the wafer transfer device 13. Then, the transfer arm 12 sequentially transfers the wafer W to the processing apparatuses 6 to 8 or the processing apparatuses 9 to 11. In this way, a cleaning process for removing impurities such as organic contaminants and particles adhering to the surface of the wafer W is performed.

Here, the cleaning process of the processing apparatus 6 will be described as a representative. As shown in FIG. 3, the storage tank 30 is replenished in advance with a processing stock solution such as an aqueous ammonia solution (NH ₄ OH), hydrogen peroxide solution (H ₂ O ₂ ), or pure water (H ₂ O) from the replenishing mechanism 40. To do. During standby, the APM processing liquid in the storage tank 30 is circulated to the adjustment circuit 32 by operating the pump 65, and the temperature is adjusted and purified by the heater 67 and the filter 68.

  Then, the wafer W is carried into the processing apparatus 6 and, as shown in FIG. 2, the wafer W held by the holding member 26 is rotated together with the rotary table 23 by the operation of the up-and-down rotation mechanism 21 and supplied. The nozzle 27 is moved above the wafer W. Then, after opening the valve 70, the valve 73 is opened, the APM processing liquid is caused to flow into the supply circuit 33, the APM processing liquid is supplied from the supply nozzle 27 to the surface of the wafer W, and SC1 cleaning is performed. The APM processing liquid used for the SC1 cleaning is drained from the drainage conduit 28, and after the bubbles are removed by the gas-liquid separation mechanism 52, it is recovered to the storage tank 30 via the recovery circuit 31. Then, the temperature adjustment and cleaning are performed again in the adjustment circuit 32, and the APM processing liquid adjusted in this way flows into the supply circuit 33 and is reused for SC1 cleaning.

  When the predetermined time elapses and the SC1 cleaning with the APM processing liquid is completed, the processing apparatus 6 performs a rinsing process on the front and back surfaces of the wafer W. Finally, the wafer W is dried by rotating the rotary table 23 at a high speed, and is carried out of the processing apparatus 6. Then, new wafers W that have not yet been subjected to the cleaning process are successively loaded into the processing apparatus 6 and the cleaning process is repeated thereafter.

  By the way, in this case, ammonia easily evaporates. As the SC1 cleaning is repeated, the ammonia concentration in the APM treatment liquid gradually decreases as it is allowed to stand, and similarly the peroxidation in the APM treatment liquid. The hydrogen concentration will also gradually decrease. Further, the APM processing liquid remaining in the container 20 is washed away, for example, during the rinsing process, and flows out from the processing apparatus 6 by a considerable amount. Therefore, the replenishment mechanism 40 determines the number of wafers W to be processed and the cleaning time in order to prevent the SC1 cleaning from being affected by the decrease in the concentration of ammonia and hydrogen peroxide in the APM processing liquid and the decrease in the amount of the APM processing liquid. Correspondingly, an aqueous ammonia solution, a hydrogen peroxide solution, and pure water are replenished to the storage tank 30 by a predetermined amount, respectively, and these processing stock solutions are mixed. Thereby, in the storage tank 30, the component ratio and the amount of the APM processing liquid can be stably secured so as not to interfere with the SC1 cleaning.

  Further, the timing of replenishing the aqueous ammonia solution, hydrogen peroxide solution, and pure water may be obtained in advance by experiments or the like using the number of wafers W processed and the cleaning time as a guide. As described above, since the optimum time for replenishing these processing stock solutions is determined, a measuring device such as a concentration sensor is not required. In addition, changes in the recovery rate and component ratio of the APM treatment liquid are obtained in advance, and the total replenishment amount of the ammonia aqueous solution, hydrogen peroxide solution, and pure water, and the replenishment ratio of each are determined.

  In this way, the wafers W carried out from the processing apparatus 6 are sequentially transferred to the processing apparatuses 7 and 8, and are transferred into the carrier C again after the processing process in the cleaning processing unit 4 is completed. Moreover, the same processing steps are performed in the processing devices 9 to 11. Then, the same processing steps are performed for the remaining 24 wafers W one by one, and when the processing steps for 25 wafers W are completed, they are carried out of the cleaning processing system 1 in units of carriers C.

  Thus, according to the processing apparatus 6 of the present embodiment, the component ratio and the liquid amount of the APM processing liquid can be stably secured in the storage tank 30. Therefore, good SC1 cleaning can be performed continuously. Further, a measuring device such as a concentration sensor is not necessary, and the processing device 6 can be simplified. In addition, consumption of the APM processing liquid can be minimized. Therefore, it is excellent in management related to the APM processing liquid such as disposal.

  Next, processing apparatuses 7 and 10 that perform DHF cleaning using a DHF processing solution in which hydrofluoric acid and pure water are mixed will be described. As shown in FIG. 5, a replenishment mechanism 80 for replenishing the storage tank 30 with hydrofluoric acid and pure water is provided. The replenishing mechanism 80 includes a hydrofluoric acid replenishing system 83 including a tank 81 and a pump 82 that store hydrofluoric acid adjusted to a predetermined concentration, and a pure water replenishing system 86 in which a valve 85 is disposed in a pure water supply circuit 84. And. In addition, since it is the same structure as the processing apparatus 6 demonstrated previously except the structure of the replenishment mechanism 80, the duplicate description is abbreviate | omitted by attaching | subjecting the same code | symbol about the component which has the same function and structure. To do.

  According to such a configuration, the replenishing mechanism 80 continuously replenishes the storage tank 30 with pure water without interruption, while replenishing the storage tank 30 with hydrofluoric acid at a predetermined time. Instead, the storage tank 30 is replenished intermittently several times. As a result, the hydrofluoric acid in the DHF treatment liquid in the storage tank 30 is kept at a predetermined concentration without causing a rapid concentration change. Therefore, similar to the processing apparatus 6, good DHF cleaning and simplification of the apparatus can be realized.

  In addition, this invention is not limited to the said embodiment, A various aspect can be taken. For example, the storage tank may be replenished with a predetermined amount of aqueous ammonia solution, hydrogen peroxide solution, and pure water each time a predetermined time elapses after integrating the wafer cleaning time.

  This cleaning method will be described along with the SC1 cleaning performed in the processing apparatuses 6 and 9. For example, the cleaning time per wafer W is set to 30 seconds (sec), and 30 cc of ammonia aqueous solution, 60 cc of hydrogen peroxide water, and 20 cc of pure water are replenished to the storage tank 30 every 30 seconds. The SC1 cleaning at this time will be described with reference to FIG. 6. As shown in FIG. 6, at the end of the first SC1 cleaning (integrated cleaning time: 30 seconds), at the end of the second SC1 cleaning ( Accumulated cleaning time: 60 seconds), the replenishment tank 30 is replenished with an aqueous ammonia solution, a hydrogen peroxide solution, and pure water. Thereafter, when the accumulated cleaning time becomes a multiple of 30 seconds, the replenishment is performed and the SC1 cleaning is repeated.

  As another example, the cleaning time per wafer W is 50 seconds, and 30 cc of ammonia aqueous solution, 60 cc of hydrogen peroxide water, and 20 cc of pure water are replenished to the storage tank 30 every 30 seconds. . The SC1 cleaning at this time will be described with reference to FIG. 7. As shown in FIG. 7, in the first SC1 cleaning, replenishment is performed 30 seconds after the start of cleaning (integrated cleaning time: 30 seconds). In the first SC1 cleaning, replenishment is performed 10 seconds after the start of cleaning (integrated cleaning time: 60 seconds) and 40 seconds later (integrated cleaning time: 90 seconds). Thereafter, when the accumulated cleaning time becomes a multiple of 30 seconds, the replenishment is performed and the SC1 cleaning is repeated.

  According to such a cleaning method, the cleaning time is integrated, and each time the integrated cleaning time reaches a predetermined time, the replenishment tank 30 is replenished with an aqueous ammonia solution, a hydrogen peroxide solution, and pure water by a predetermined amount. Even if the cleaning time per wafer W changes, the storage tank 30 can be periodically replenished with an aqueous ammonia solution, a hydrogen peroxide solution, and pure water in accordance with the cleaning time. Therefore, it is possible to stably secure the component ratio and the liquid amount of the APM processing liquid.

  In particular, in this cleaning method, the SC1 cleaning of the wafer W is not replenished every time. Therefore, when the APM processing liquid is used for a predetermined time based on experimental data or the like in advance, the component ratio and liquid volume of the APM processing liquid are used. If a predetermined liquid amount for replenishing ammonia aqueous solution, hydrogen peroxide solution, and pure water is obtained, even if the cleaning time per wafer W changes thereafter, In each case, it is not necessary to change the setting of the time and the amount of liquid to replenish the aqueous ammonia solution, hydrogen peroxide solution, and pure water.

  Such a cleaning method can also be applied to a processing apparatus that drains the processing liquid to the outside of the container without collecting it in the storage tank. The processing devices 90 and 91 shown in FIG. 8 are examples thereof. As shown in FIG. 8, the APM processing liquid stored in the storage tank 30 is drained out of the container 20 through the drain line 28 after being used for SC1 cleaning. In this case, the drained APM processing liquid is collected, for example, in another tank provided in the factory and reused separately.

  In the processing apparatuses 90 and 91, even when the APM processing liquid is drained, the cleaning time is integrated, and each time the integrated cleaning time reaches a predetermined time, a predetermined amount of aqueous ammonia solution and peroxide are added. Since hydrogen water and pure water are replenished to the replenishing tank 30, it is possible to prevent a situation in which the storage tank 30 becomes empty and SC1 cleaning cannot be performed. Of course, the component ratio and amount of the APM treatment liquid can be secured stably.

  Further, the substrate is not limited to the wafer W as in the present embodiment, but may be an LCD substrate, a glass substrate, a CD substrate, a photomask, a printed substrate, a ceramic substrate, or the like.

  Next, an example of the present invention was performed. The processing apparatus described in FIGS. 2 and 3 was actually manufactured, and the change in the concentration of ammonia and hydrogen peroxide in the APM processing solution and the amount of decrease in the APM processing solution were investigated. In this case, the APM treatment liquid is a liquid in which an aqueous ammonia solution adjusted to a predetermined concentration, a hydrogen peroxide solution adjusted to a predetermined concentration, and pure water are mixed at a predetermined ratio. The test object is a 12-inch wafer.

First, when the wafer was cleaned, changes in the concentrations of ammonia (NH ₄ OH) and hydrogen peroxide (H ₂ O ₂ ) in the APM processing solution were examined. In this case, one wafer was SC1 cleaned for 30 seconds (sec), and a concentration change was observed for 30 minutes (min). The result is shown in FIG. One wafer was SC1 cleaned for a total of 10 seconds for 60 seconds, and the change in density was observed for 40 minutes. The result is shown in FIG. In any case, during the experiment, the stock solution such as aqueous ammonia solution, hydrogen peroxide solution, and pure water is not replenished during the experiment except when it is first generated in the storage tank. 9 and 10, graph line a and graph line c indicate changes in ammonia concentration, and graph line b and graph line d indicate changes in hydrogen peroxide concentration. As shown in FIGS. 9 and 10, it can be understood that the concentration of ammonia or hydrogen peroxide gradually decreases as the cleaning time elapses. Although no experiment was conducted, it is expected that the ammonia and hydrogen peroxide concentrations will gradually decrease at the same ratio even if the cleaning time increases to 90 seconds and 120 seconds.

  On the other hand, the amount of APM treatment liquid lowered when recovered in the storage tank was examined. In this case, the cleaning time per wafer was sequentially changed to 30 seconds, 60 seconds, 90 seconds, and 120 seconds. In each case, SC1 cleaning under the same conditions was repeated 10 times, and the average value was shown in the graph. The result is shown in FIG. The graph line e in FIG. 11 shows the change in the amount of APM processing liquid drop, and from this graph line e, the cleaning time per wafer is 30, 60, 90, 120 seconds. It can be understood that as the amount increases, the amount of liquid drop increases and the amount of APM treatment liquid gradually decreases.

  As described above, on the basis of this experiment, the amount of liquid to be replenished with the aqueous ammonia solution, hydrogen peroxide solution, and pure water and the wafer so that the component ratio and amount of the APM processing solution can be stably secured in the storage tank. FIG. 12 is a graph showing the relationship with the cleaning time per sheet. In FIG. 12, the graph line f indicates the relationship between the amount of liquid replenished with the aqueous ammonia solution and the cleaning time, and the graph line g indicates the relationship between the amount of liquid replenished with hydrogen peroxide and the cleaning time. h indicates the relationship between the amount of pure water replenished and the cleaning time. Thus, according to FIG. 12, if the timing and amount of replenishment of the aqueous ammonia solution, hydrogen peroxide solution, and pure water are determined, good SC1 cleaning can be performed.

  Next, changes in the concentrations of ammonia and hydrogen peroxide in the APM processing solution were examined when each processing stock solution was not replenished after the APM processing solution was generated without cleaning the wafer. That is, first, an aqueous ammonia solution, a hydrogen peroxide solution, and pure water are replenished to the storage tank to generate an APM processing solution. Thereafter, the APM treatment liquid was left unattended for 60 minutes, and the concentration change during this period was observed. The result is shown in FIG. In FIG. 13, a graph line i indicates a change in ammonia concentration, and a graph line j indicates a change in hydrogen peroxide concentration. As shown in FIG. 13, it can be understood that the concentration of ammonia or hydrogen peroxide gradually decreases as the cleaning time elapses. From this experiment and the change in the amount of APM liquid drop when the APM processing liquid is left as it is, in the case where each processing stock solution is not replenished after the APM processing liquid is generated without cleaning the wafer. The replenishment amount of each processing stock solution per unit time can be calculated. According to the replenishment amount of each processing stock solution per unit time calculated in this way, the replenishment of each processing stock solution is repeated at a predetermined time regardless of whether or not the wafer is cleaned. Thereby, the concentration of ammonia and hydrogen peroxide in the APM treatment liquid and the amount of the APM treatment liquid can be maintained at predetermined values.

  Next, the processing apparatus described in FIG. 5 was actually manufactured, and the concentration change of hydrofluoric acid (HF) in the DHF processing solution was examined. In this case, the DHF treatment liquid is a liquid in which hydrofluoric acid adjusted to a predetermined concentration and pure water are mixed at a predetermined ratio. The test object is a 12-inch wafer. Then, one wafer was DHF cleaned for a predetermined time, and this was continued several times.

  First, the graph line k in FIG. 14 shows a change in the concentration of hydrofluoric acid in the DHF treatment liquid when a predetermined amount of hydrofluoric acid is replenished to the storage tank at a rate of once every 120 seconds. . It took about 6 seconds to replenish the hydrofluoric acid. Further, the graph line l in FIG. 15 shows the concentration change of hydrofluoric acid in the DHF treatment liquid when a predetermined amount of hydrofluoric acid is replenished to the storage tank at a rate of 3 times every 120 seconds. . It took about 2 seconds to replenish hydrofluoric acid. As can be understood from a comparison between the graph line k in FIG. 14 and the graph l in FIG. 15, the hydrofluoric acid replenishment performed several times intermittently for 120 seconds is more likely to occur in the DHF treatment solution. The concentration change of the acid becomes flat. Thus, if the number of times of replenishing hydrofluoric acid is increased, the hydrofluoric acid concentration in the DHF treatment liquid can be maintained at a predetermined concentration, and good DHF cleaning can be performed.

  The present invention can be applied to, for example, cleaning of semiconductor wafers, LCD glass plates, and other processing.

It is a top view of the washing processing system provided with the processing device concerning this embodiment. It is a schematic sectional drawing of a processing apparatus. It is explanatory drawing of the circuit concerning APM processing liquid. It is a perspective view of a gas-liquid separation mechanism. It is explanatory drawing of the circuit concerning a DHF process liquid. It is a figure explaining an example of SC1 washing | cleaning in the case of replenishing a storage tank with ammonia aqueous solution, hydrogen peroxide solution, and pure water by predetermined liquid quantity every time predetermined time passes, integrating cleaning time. It is a figure explaining the other example of SC1 washing | cleaning in the case of replenishing a storage tank with ammonia aqueous solution, hydrogen peroxide solution, and pure water by predetermined liquid quantity every time predetermined time passes integrating | accumulating cleaning time. It is explanatory drawing of the other circuit concerning APM process liquid applicable to SC1 washing | cleaning of FIG.6 and FIG.7. It is a graph which shows the density | concentration change of ammonia and hydrogen peroxide in an APM processing liquid when the cleaning time per wafer is 30 seconds. It is a graph which shows the density | concentration change of ammonia and hydrogen peroxide in an APM processing liquid when the cleaning time per wafer is 60 seconds. It is a graph which shows the relationship between the washing | cleaning time per wafer, and the liquid fall amount of an APM process liquid. It is a graph which shows the relationship between the amount of liquid which replenishes ammonia aqueous solution, hydrogen peroxide solution, and pure water, and the cleaning time per wafer so that the component ratio and amount of APM processing liquid can be secured stably. . It is a graph which shows the density | concentration change of ammonia and hydrogen peroxide in an APM processing liquid when not replenishing each processing stock solution after producing | generating an APM processing liquid without performing the wafer cleaning process. It is a graph which shows the density | concentration change of the hydrofluoric acid in a DHF process liquid when a predetermined amount of hydrofluoric acid is replenished to a storage tank every 120 seconds. It is a graph which shows the density | concentration change of the hydrofluoric acid in a DHF process liquid when a predetermined amount of hydrofluoric acid is replenished to a storage tank every 40 seconds.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cleaning processing system 6,7,8,9,10,11 Processing apparatus 30 Storage tank 31 Collection circuit 32 Adjustment circuit 33 Supply circuit 40 Replenishment mechanism 52 Gas-liquid separation mechanism W Wafer

Claims (9)

In a processing apparatus for replenishing a storage tank with a plurality of processing stock solutions at a predetermined ratio and supplying the processing liquid in the storage tank to a substrate for processing,
A processing apparatus comprising: a replenishment mechanism that replenishes the storage tank with a processing stock solution corresponding to the number of processing substrates and processing time, and supplying the processing solution generated by mixing the processing stock solution to the substrate. . In a processing apparatus for replenishing a storage tank with a plurality of processing stock solutions at a predetermined ratio and supplying the processing liquid in the storage tank to a substrate for processing,
A process generated by mixing the processing stock solution by integrating a processing time of the substrate and providing a replenishment mechanism for replenishing the processing stock solution from the replenishment mechanism to the storage tank every time the accumulated processing time reaches a predetermined time. A processing apparatus for supplying a liquid to a substrate. The processing apparatus according to claim 1, further comprising: a holding unit that rotatably holds the substrate; and a supply unit that supplies a processing liquid to the substrate held by the holding unit. A recovery circuit that recovers the processing liquid that has processed the substrate to the storage tank, an adjustment circuit that adjusts the processing liquid in the storage tank, and a supply circuit that supplies the processing liquid in the storage tank to the substrate are provided. The processing apparatus according to claim 1, 2, or 3. The processing apparatus according to claim 4, wherein a gas-liquid separation mechanism is arranged in the middle of the recovery circuit. In a processing method of supplying a processing liquid stored in a storage tank to a substrate,
The processing stock solution is replenished to the storage tank corresponding to the number of processed substrates and the processing time, and the processing liquid generated by mixing the processing stock solution supplemented to the storage tank is supplied to the substrate. Method. In a processing method of supplying a processing liquid stored in a storage tank to a substrate,
The processing time of the substrate is integrated, and each time the integrated processing time reaches a predetermined time, the processing stock solution is replenished to the storage tank, and the processing liquid generated by mixing the processing stock solution supplied to the storage tank is mixed with the substrate. A processing method, characterized by being supplied to The processing method according to claim 6 or 7, wherein when the stock solution for processing is replenished to the storage tank, replenishment is performed with a predetermined liquid amount. The processing method according to claim 6, wherein the processing liquid that has processed the substrate is collected in the storage tank.

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