Liquid drip preventing mechanism, liquid drip preventing method, and spin processing device

Abstract

To provide a liquid drip preventing mechanism, a liquid drip preventing method, and a spin processing device, which can prevent a chemical solution from dripping from a tip of a drop nozzle at or after stop of supply of the chemical solution while keeping the flow rate of the chemical solution that is necessary for wafer surface processing.SOLUTION: A liquid drip preventing mechanism includes: a drop nozzle formed of a chemical-resistant resin and including a direct trunk nozzle body configured by a direct trunk part and a drip opening part connected to a lower part of the direct trunk part; a chemical solution supplying device that supplies a chemical solution to the drop nozzle in a chemical solution processing time supply amount when the wafer is processed with the chemical solution and supplies the chemical solution in a chemical solution end time supply amount when the processing of the wafer with the chemical solution ends; and a chemical solution supply stopping device that stops the supply of the chemical solution that is supplied in the chemical solution end time supply amount. The direct trunk nozzle body is installed so as to be orthogonal to the wafer and the chemical solution processing time supply amount is four times or more the chemical solution end time supply amount.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a mechanism and method for preventing dripping of a drip nozzle of a spin processing apparatus that drips chemical liquid used in a semiconductor manufacturing process onto a wafer placed on the spin processing apparatus for chemical processing, and also to a spin processing apparatus that uses the drip prevention mechanism. [Background technology]

[0002] In the semiconductor manufacturing process, various semiconductor wafer surface treatments are performed according to each process, including etching to remove damaged layers after backgrinding, coating of a developing solution on the wafer, developing of a wafer with a circuit pattern exposed on the surface and then coated with a developing solution, and cleaning of the wafer surface.

[0003] As a spin processing apparatus for performing such various wafer surface processing, the apparatus described in Patent Document 1 is known.

[0004] Such spin processing apparatuses are provided with a drip nozzle for dripping a chemical onto the placed wafer. In Patent Document 1, this drip nozzle is called an injection pipe.

[0005] In a spin processing apparatus such as that shown in Patent Document 1, the chemical solution is temperature-regulated in a chemical solution circulation tank and circulated through piping. While maintaining a constant temperature, the chemical solution is repeatedly circulated up to near a chamber (a hood that covers the surface treatment area of ​​the wafer in the spin processing apparatus), where the piping branches off near the chamber, and the chemical solution is dripped onto the wafer from a drip nozzle while the dripping of the chemical solution is controlled on / off by an air-operated valve.

[0006] However, it was found that when the supply of the chemical solution was stopped by the air operated valve, a water hammer phenomenon occurred, causing the chemical solution to drip and splash from the tip of the drip nozzle.

[0007] It was found that even if a flow controller was used to stop the supply of the chemical solution, the water hammer phenomenon still occurred, causing the chemical solution to drip and splash from the tip of the drip nozzle.

[0008] Even if only one or a few drops of chemical solution splash from the tip of the dropping nozzle, if they fall onto the wafer, the appearance of the wafer surface may change, causing problems in the process.

[0009] On the other hand, in recent years, semiconductors have become more highly integrated and larger in diameter, with 12-inch or larger wafers being the mainstream, and the diameter is becoming larger and larger. For wafers of 12 inches or larger, the flow rate of the chemical solution is required to be 1.5 L / min, for example, if the pipe diameter of the drip nozzle is 1 / 4 inch. For example, if the chemical solution is an etching solution, an etching rate of 13,000 Å / min or more is required. It is necessary.

[0010] In this way, it was necessary to maintain the flow rate of the chemical liquid required for surface treatment of the wafer while preventing the chemical liquid from dripping and splashing from the tip of the drip nozzle when and after the supply of the chemical liquid was stopped, thereby preventing any malfunctions in the processing of the wafer surface. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Patent Publication No. 2001-267278 [Patent Document 2] WO2017 / 204082 [Patent Document 3] Patent Publication No. 2017-188549 Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention has been made in consideration of the above-mentioned problems with the conventional technology, and has an object to provide a drip prevention mechanism, a drip prevention method, and a spin processing apparatus that prevent the chemical liquid from dripping from the tip of the drip nozzle when and after the supply of the chemical liquid is stopped, while maintaining the flow rate of the chemical liquid required for surface processing of a wafer. [Means for solving the problem]

[0013] In order to solve the above problems, the liquid dripping prevention mechanism of the present invention is a liquid dripping prevention mechanism for a drip nozzle of a spin processing device for dripping a chemical liquid used in a semiconductor manufacturing process onto a wafer placed on the spin processing device to perform chemical processing, the liquid dripping prevention mechanism including a drip nozzle made of a chemical-resistant resin and having a straight-body nozzle body composed of a straight body portion and a drip opening connected to a lower portion of the straight body portion, a chemical liquid supplying device that supplies the chemical liquid to the drip nozzle at a chemical liquid processing time supply amount during chemical processing of the wafer, and supplies the chemical liquid at a chemical liquid end supply amount when chemical processing of the wafer is completed, and a chemical liquid supply stopping device that stops the supply of the chemical liquid supplied at the chemical liquid end supply amount, wherein the straight-body nozzle body is installed perpendicular to the wafer, and the chemical liquid processing time supply amount is at least four times greater than the chemical liquid end supply amount.

[0014] It is preferable that the length of the straight body portion is at least twice the diameter of the drip opening.

[0015] It is preferable that the straight-body nozzle body is a straight-body nozzle body in which the drip opening is connected flush with the straight-body portion, and that the inner diameter of the straight-body nozzle body is 1 / 4 inch or less.

[0016] It is preferred that the wafer is 12 inches or greater in diameter.

[0017] It is preferable that a plurality of the drip nozzles are provided, and different chemical solutions are dripped onto the wafer from each drip nozzle to perform chemical processing.

[0018] It is preferable that the chemical solution is an etching solution, and that the amount of the chemical solution supplied during processing is such that the etching rate of the wafer is 13000 Å / min or more.

[0019] It is preferable that the nozzle body has a gravity suck-back mechanism for sucking up the chemical liquid remaining in the straight body portion after the supply of the chemical liquid is stopped, the gravity suck-back mechanism being made of a chemical-resistant resin and having a piping connected to a curved portion formed at the upper part of the straight body nozzle body and a liquid recovery opening portion connected to the piping, the liquid recovery opening portion being positioned at a lower position than the drip opening portion.

[0020] It is preferable that the liquid recovery nozzle body be provided with an on-off valve, and the liquid chemical remaining in the curved portion and the piping be drained by opening the on-off valve.

[0021] The liquid dripping prevention method of the present invention is a method for preventing liquid dripping from a drip nozzle of a spin processing apparatus using the liquid dripping prevention mechanism, and includes the steps of: supplying the chemical liquid to the drip nozzle at a chemical processing time supply amount when the wafer is processed with the chemical liquid; supplying the chemical liquid at a chemical processing end supply amount when the chemical processing of the wafer is completed; and stopping the supply of the chemical liquid supplied at the chemical processing end supply amount, wherein the chemical processing time supply amount is at least four times greater than the chemical processing end supply amount.

[0022] It is preferable that the chemical solution is an etching solution, and that the amount of the chemical solution supplied during processing is such that the etching rate of the wafer is 13000 Å / min or more.

[0023] Furthermore, the liquid dripping prevention method of the present invention is a method for preventing liquid dripping from a drip nozzle of a spin processing apparatus using the liquid dripping prevention mechanism, and includes a step of supplying the chemical liquid to the drip nozzle at a chemical processing time supply amount when the wafer is processed with the chemical liquid, a step of supplying the chemical liquid at a chemical processing end supply amount when the chemical processing of the wafer is completed, a step of stopping the supply of the chemical liquid supplied at the chemical processing end supply amount, and a suck back step of sucking up the chemical liquid remaining in the straight body portion after the chemical liquid supply is stopped after the stopping step, wherein the chemical processing time supply amount is four or more times greater than the chemical processing end supply amount.

[0024] The spin processing apparatus of the present invention is a spin processing apparatus incorporating the liquid drip prevention mechanism, and performs chemical processing by dripping a chemical liquid onto a wafer placed thereon.

[0025] It is preferred that the wafer is 12 inches or greater in diameter. Effect of the Invention

[0026] According to the present invention, it is possible to provide a significant effect of providing a drip prevention mechanism, a drip prevention method, and a spin processing apparatus that prevent the chemical liquid from dripping from the tip of the drip nozzle when and after the supply of the chemical liquid is stopped while maintaining the flow rate of the chemical liquid required for surface processing of a wafer. [Brief description of the drawings]

[0027] [Figure 1] 1 is a schematic diagram showing a main part of a spin treatment device equipped with a drip prevention mechanism according to an embodiment of the present invention; [Diagram 2] 1 is a schematic diagram showing a main part of one embodiment of a spin treatment device equipped with a gravity suck-back mechanism. FIG. [Diagram 3] 1 is a schematic diagram showing the chemical liquid remaining in the straight body portion of the dropping nozzle. FIG. [Figure 4] FIG. 2 is a perspective view showing one embodiment of a mesh member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] The following describes the embodiments of the present invention, but these embodiments are shown by way of example only, and it goes without saying that various modifications are possible without departing from the technical spirit of the present invention. In the drawings, the same members are represented by the same reference numerals.

[0029] In Fig. 1, reference numeral 10 denotes a spin processing apparatus equipped with a drip prevention mechanism 12 of the present invention. The spin processing apparatus 10 is a spin processing apparatus that processes the wafer surface with a processing liquid or a cleaning liquid, similar to the spin processing apparatus described in Patent Document 1. The wafer may be held by a plurality of outer periphery movable pins as described in Patent Document 2.

[0030] The spin processing apparatus 10 has a wafer rotating / holding device 14 that rotates and holds the wafer to be surface-treated, and a chemical recovery mechanism 16 made of polyvinyl chloride (PVC) that is provided around the wafer rotating / holding device 14 so as to be movable up and down. The chemical recovery mechanism 16 is made up of a plurality of annular chemical recovery troughs 18a, 18b, 18c that are provided so as to be movable up and down relative to each other, and the plurality of annular chemical recovery troughs 18a, 18b, 18c are used differently depending on the type of chemical (processing liquid) 20 and cleaning liquid 22 to separate and recover each chemical 20.

[0031] The drip prevention mechanism 12 is a drip prevention mechanism for the drip nozzle 24 of the spin processing device 10, which drips the chemical solution 20 used in the semiconductor manufacturing process onto a wafer placed on the spin processing device 10 for chemical processing. The drip prevention mechanism 12 can prevent the chemical solution 20 from dripping from the tip of the drip nozzle 24 when and after the supply of the chemical solution 20 is stopped.

[0032] As shown in Fig. 2 and Fig. 3, the drip nozzle 24 is made of a chemical-resistant resin and has a straight-body nozzle body 30 composed of a straight-body portion 26 and a drip opening 28 connected to the lower part of the straight-body portion 26. The chemical liquid 20 is a mixed acid, a hydrofluoric acid, or a chemical liquid 20 having a different concentration thereof, and the cleaning liquid 22 is a rinse liquid such as pure water. In the example of Fig. 1, a total of seven drip nozzles 24 for the chemical liquid 20 and one cleaning liquid drip nozzle 32 for the cleaning liquid 22 are provided. Although only one drip nozzle 24 may be used, it is preferable to have a plurality of drip nozzles since different chemical liquids can be dripped without changing the drip nozzle.

[0033] The chemical-resistant resin constituting the dropping nozzle 24 is preferably a fluororesin such as PFA (perfluoroalkoxyalkane) or PTFE (polytetrafluoroethylene).

[0034] Reference numeral 33 denotes a swinging arm for swinging the drip nozzle 24. The swinging arm 33 may be configured to swing a drip nozzle (an etching solution supply nozzle in Patent Document 3) as described in Patent Document 3. Reference numeral 35 denotes a cleaning solution swinging arm for moving or swinging the cleaning solution drip nozzle 32 above the wafer as necessary during the cleaning step.

[0035] The drip prevention mechanism 12 includes a chemical supply device 34 that supplies the chemical liquid 20 to the drip nozzle 24 at a chemical processing supply amount during chemical processing of the wafer, and supplies the chemical liquid 20 at a chemical completion supply amount when chemical processing of the wafer is completed, and a chemical supply stop device 36 that stops the supply of the chemical liquid 20 supplied at the chemical completion supply amount. An example of the chemical supply device 34 is a flow rate controller, and an example of the chemical supply stop device 36 is an air operated valve. That is, the drip prevention mechanism 12 includes the chemical supply device 34 that adjusts the flow rate of the chemical liquid 20, and the chemical supply stop device 36 that can instantly stop the supply of the chemical liquid 20.

[0036] Reference numeral 38 denotes a circulation tank for the chemical solution 20, and the chemical solution 20 returned to the circulation tank is reused. Reference numeral 37 denotes a chamber which is a hood that covers the surface treatment area of ​​the wafer in the spin processing apparatus 10.

[0037] In the drip prevention mechanism 12, the drip nozzle 24 is installed so that the straight nozzle body 30 is perpendicular to the wafer. The drip nozzle 24 is configured so that the amount of the chemical solution supplied during the chemical treatment is four or more times larger than the amount of the chemical solution supplied at the end of the chemical treatment.

[0038] In the illustrated example, the straight body portion 26 is configured to have a length that is at least twice the diameter of the drip opening 28 .

[0039] The straight-body nozzle body 30 is a straight-body nozzle body in which the drip opening 28 is connected flush with the straight-body portion 26 .

[0040] Also, it is preferable that the wafers placed on the spin processing device 10 for chemical processing have a diameter of 12 inches or more. In the case of wafers with a diameter of 12 inches or more, the amount of chemical supply during processing is preferably 1.5 L / min flow rate, and the amount of chemical supply at the end of processing is preferably 0.3 L / min or less. More preferably, in the case of wafers with a diameter of 12 inches or more, the amount of chemical supply at the end of processing is preferably 1.5 L / min flow rate, and the amount of chemical supply at the end of processing is preferably 0.2 L / min or less.

[0041] The chemical solution 20 is, for example, an etching solution. In the case of the etching solution, from the viewpoint of production efficiency, the supply amount during the chemical solution processing is set to 1000 Å / min so that the etching rate of the wafer is 13000 Å / min. It is preferable that the supply amount is equal to or more than this.

[0042] 3 shows the state in which the chemical liquid 20 remains in the straight body portion 26 of the drip nozzle 24, whose straight body nozzle body 30 has an inner diameter of 1 / 4 inch. When the chemical liquid 20 is continuously supplied through a pipe and dripped onto a wafer from the drip nozzle 24, when the supply of the chemical liquid 20 is stopped, the chemical liquid 20 remains in the straight body portion 26. In other words, the chemical liquid, such as a mixed acid, remains in the straight body portion 26 in a state where the chemical liquid hangs down by about 1 mm due to surface tension at the drip opening 28, which is the nozzle tip.

[0043] At this time, if the supply of the chemical solution 20 is immediately and completely stopped from the supply rate of, for example, 1.5 L / min during chemical treatment by using an air operated valve or a flow controller, the chemical solution 20 will drip and splash from the tip of the drip nozzle 24 due to the water hammer phenomenon (water hammer action caused by a sudden change in pressure inside the piping).

[0044] In the present invention, the occurrence of this water hammer phenomenon can be prevented, so that the chemical solution 20 does not drip and splash from the tip of the dripping nozzle 24.

[0045] The inner diameter of the straight-body nozzle body 30 is preferably 1 / 4 inch or less. In the illustrated example, the straight-body nozzle body 30 is a straight-body nozzle body in which the drip opening 28 is connected flush with the straight-body portion 26, and the inner diameter of the straight-body nozzle body 30 is 1 / 4 inch. The inner wall of the straight-body nozzle body 30 is preferably a smooth surface without irregularities.

[0046] When using a drip nozzle having an inner diameter of the straight-body nozzle body 30 exceeding 1 / 4 inch, it is preferable to attach a mesh member 40 made of a chemical-resistant resin such as PFA or PTFE to the drip opening 28 of the drip nozzle 24 as shown in Fig. 4. The mesh member 40 is composed of an annular portion 42 fitted to the drip opening 28 of the drip nozzle 24 and a mesh body 44 attached to the annular portion 42. By attaching the mesh member 40 to the drip opening 28 of the drip nozzle 24, when the supply of the chemical solution 20 is stopped, the chemical solution such as mixed acid will remain in the straight-body portion 26 in a state where it hangs down by about 1 mm due to the surface tension of the mesh member 40 at the drip opening 28, which is the nozzle tip.

[0047] As shown in FIG. 3, when the supply of the drug solution 20 that has been continuously supplied is stopped, the drug solution 20 remains in the straight body portion 26, so it is more preferable to provide a suck-back mechanism for sucking up this remaining drug solution 20.

[0048] 2, the liquid drip prevention mechanism 12 has a weight suck-back mechanism 46. The weight suck-back mechanism 46 is a weight suck-back mechanism for sucking the liquid medicine 20 remaining in the straight body portion 26 after the supply of the liquid medicine 20 is stopped.

[0049] The gravity suck-back mechanism 46 is made of a chemical-resistant resin, has a pipe 50 connected to the curved portion 48 of the drip nozzle 24 formed on the upper portion of the straight nozzle body 30, and a liquid recovery opening 52 connected to the pipe 50, and includes a liquid recovery nozzle body 54 in which the liquid recovery opening 52 is located at a lower position than the drip opening 28. The liquid recovery opening 52 is provided in a liquid recovery box 56, and the chemical solution 20 is recovered in the liquid recovery box 56. Alternatively, as long as the liquid recovery opening 52 is provided, the liquid can be directly discharged through the liquid recovery opening 52. In the example of FIG. 2, an example is shown in which the circulation tank 38 is further connected to the liquid recovery box 56. As a result, the sucked-back chemical solution returns to the circulation tank 38.

[0050] As the chemical-resistant resin constituting the curved portion 48 of the drip nozzle 24 and the piping 50, a fluororesin such as PFA (perfluoroalkoxyalkane) or PTFE (polytetrafluoroethylene) is suitable.

[0051] As shown in FIG. 2, the gravity suck-back mechanism 46 has the liquid recovery opening 52 disposed at a position lower than the dripping opening 28 by a distance D1. Therefore, when the chemical liquid 20 is continuously supplied through the inside of the pipe 50 and further through the curved portion 48 of the dripping nozzle 24 and dripped onto the wafer from the dripping nozzle 24, when the supply of the chemical liquid 20 is stopped, the chemical liquid 20 remains in the straight body portion 26, the curved portion 48, and the pipe 50. However, since the liquid recovery opening 52 is disposed at a position lower than the dripping opening 28 by a distance D1, a suck-back phenomenon occurs in which the chemical liquid 20 remaining in the straight body portion 26 is sucked by the weight of the chemical liquid 20 due to potential energy and gravity, and the chemical liquid 20 is recovered from the liquid recovery opening 52 without the need for a pump or the like. This suck-back phenomenon is due to the principle of a siphon.

[0052] In other words, when the supply of the chemical liquid 20 is stopped, the straight body portion 26, the curved portion 48, and the piping 50 will be filled with the chemical liquid 20, but due to the relationship between the drip opening 28, which is located at a high position, and the liquid recovery opening 52, which is located at a position a distance D1 lower than the drip opening 28, the chemical liquid 20 remaining in the straight body portion 26 is sucked up by its own weight and recovered from the liquid recovery opening 52 without being sucked up by a pump.

[0053] 2, reference numeral 58 denotes an on-off valve provided on the liquid recovery nozzle body 54. Reference numeral 38 denotes a circulation tank, the temperature of which is adjusted to 25 to 65°C by a heater 64, and the liquid circulates through a circulation pipe 70. A pump 66 is connected to the circulation tank 38. Reference numeral 60 denotes a valve, and reference numeral 62 denotes a flow rate controller. Reference numeral 72 also denotes a circulation pipe connected to the circulation tank 38.

[0054] An on-off valve 58 provided on the liquid recovery nozzle body 54 serves as a chemical liquid refreshing mechanism, and by opening the on-off valve 58, the chemical liquid remaining in the curved portion 48 and the piping 50 is drained. The liquid dripping from the drip opening 28, which is the nozzle tip, is sucked back by its own weight, but the degree of this suck back can be controlled by the on-off valve 58 and the flow rate controller 62.

[0055] By opening the valve 60 branched from the circulation tank 38, the liquid medicine passes through the flow rate controller 62 and passes through the branch of the gravity suck-back opening / closing valve 58 to reach the tip of the discharge nozzle.

[0056] While the piping from the valve 60 to the branch of the gravity suck-back on-off valve 58 is as short as possible, the performance of the chemical liquid present from the valve 60 to the drip opening 28, which is the tip of the nozzle, may deteriorate if it is stopped for a long time. In other words, if the chemical liquid remains at the distance L1 in Figure 2 for a long time, the temperature may change and the original performance of the chemical liquid may not be maintained.

[0057] The deteriorated liquid must be discharged from the drip opening 28 at the nozzle tip and discarded. This is called discharge of deteriorated liquid. As a means for eliminating the discharge of deteriorated liquid, the on-off valve 58 can be opened for a long time to have a function of draining the liquid up to the valve 60. In particular, after the suck-back by the gravity suck-back mechanism 46, the on-off valve 58 is opened to drain the liquid remaining in the curved portion 48 and the piping 50 indicated by the distance L1, and the pipes 50 can be emptied. In this way, the on-off valve 58 provided on the liquid recovery nozzle body 54 serves as a liquid refreshing mechanism. This makes it unnecessary to discharge deteriorated liquid by discharging the deteriorated liquid from the drip opening 28 at the nozzle tip and discarding it.

[0058] The liquid dripping prevention method of the present invention is a method for preventing liquid dripping from the drip nozzle 24 of the spin processing device 10 using the above-mentioned liquid dripping prevention mechanism 12, and includes the steps of: supplying the chemical liquid to the drip nozzle at a chemical processing time supply amount when the wafer is being processed with the chemical liquid; supplying the chemical liquid at a chemical processing end supply amount when the wafer is processed with the chemical liquid; and stopping the supply of the chemical liquid supplied at the chemical processing end supply amount, wherein the chemical processing time supply amount is at least four times greater than the chemical processing end supply amount.

[0059] When the chemical solution 20 is an etching solution, it is preferable that the amount of the chemical solution supplied during processing is such that the etching rate of the wafer is 13000 Å / min or more.

[0060] The method for preventing dripping of the present invention is a method for preventing dripping of the drip nozzle 24 of the spin processing device 10 using the dripping prevention mechanism 12, and includes a step of supplying the chemical to the drip nozzle at a supply amount during chemical processing of the wafer, a step of supplying the chemical at a supply amount at the end of chemical processing of the wafer, a step of stopping the supply of the chemical supplied at the supply amount at the end of chemical processing of the wafer, and a suck-back step of sucking the chemical remaining in the straight body after the supply of the chemical is stopped after the stopping step, and it is preferable that the supply amount during chemical processing is four or more times larger than the supply amount at the end of chemical processing. The suck-back step of sucking the chemical 20 can be performed by the gravity suck-back mechanism 46.

[0061] The spin processing apparatus of the present invention is a spin processing apparatus 10 incorporating the liquid drip prevention mechanism 12, and is a spin processing apparatus that performs chemical liquid processing by dripping a chemical liquid 20 onto a placed wafer. The wafer is preferably a wafer having a diameter of 12 inches or more. EXAMPLES

[0062] The present invention will be described in more detail below with reference to examples. However, it goes without saying that these examples are given for illustrative purposes and should not be construed as limiting.

[0063] <Test Overview> Using a drip nozzle with an inner diameter of 1 / 4 inch, set the conditions so that there is no dripping, and check for the presence or absence of dripping. Chemical solution used: Only one of the two mixed acid lines was used for the test. Approximately 14 L of mixed acid was used. The spin processing apparatus used was an MSE-5000ME manufactured by Saneki Semiconductor Industries Co., Ltd., equipped with the above-mentioned drip prevention mechanism 12 and gravity suck-back mechanism 46. Wafer: 12 inch round silicon wafer Conditional items: Suck back valve opening amount Suck Back Time -Relationship between mass flow (flow controller) and valve (air operated valve) when stopping discharge of chemical liquid Flow rate: The flow rate was changed to check for dripping. It was also evaluated whether the flow rate was sufficient or insufficient for chemical treatment. Rotation speed of wafer by wafer rotating and holding device: 800 rpm In Examples 1 and 2 (Evaluation Nos. 38-1 and 38-2), 1.5 L / min was administered for 5 seconds, followed by 0.3 L / min for 1 second. In Examples 3 to 5 (Evaluation Nos. 41, 41-2, and 41-3), 1.5 L / min was administered for 2 seconds, followed by 0.3 L / min for 1 second. Evaluation results: The results are shown in Table 1. Table 1 shows data indicating the experimental results showing the presence or absence of dripping due to the difference between the amount of chemical solution supplied during treatment and the amount of chemical solution supplied at the end of treatment.

[0064] [Table 1]

[0065] As shown in Table 1, when the amount of chemical solution supplied during treatment was changed from 1.5 L / min to 0.3 L / min at the end of treatment, the supply of chemical solution was stopped, and the suck-back process was performed, no dripping occurred. [Explanation of symbols]

[0066] 10: spin processing device, 12: liquid drip prevention mechanism, 14: wafer spinning and holding device, 16: chemical recovery mechanism, 18a, 18b, 18c: annular chemical recovery trough, 20: chemical (processing liquid), 22: cleaning liquid, 24: dripping nozzle, 26: straight body portion, 28: dripping opening, 30: straight body nozzle body, 32: cleaning liquid drip nozzle, 33: swinging arm, 34: chemical supply device, 35: swinging arm for cleaning liquid, 36: chemical supply Supply stop device, 37: chamber, 38: circulation tank, 40: mesh member, 42: annular portion, 44: mesh body, 46: weight suck-back mechanism, 48: curved portion, 50: piping, 52: liquid recovery opening, 54: liquid recovery nozzle body, 56: liquid recovery box, 58: on-off valve, 60: valve, 62: flow rate controller, 64: heater, 66: pump, 70, 72: circulation pipe, D1, L1: distance.

Claims

1. A drip prevention mechanism for a drip nozzle of a spin processing apparatus for dripping a chemical used in a semiconductor manufacturing process onto a wafer placed on the spin processing apparatus, the mechanism comprising: A drip nozzle is made of a chemically resistant resin and has a straight-body nozzle body including a straight-body portion and a drip opening portion connected to a lower portion of the straight-body portion; a chemical supplying device that supplies the chemical liquid to the drip nozzle at a chemical processing time supply amount during the chemical processing of the wafer, and supplies the chemical liquid at a chemical completion supply amount when the chemical processing of the wafer is completed; a chemical supply stopping device that stops the supply of the chemical supplied at the chemical end supply amount; Including, The straight nozzle body is disposed so as to be perpendicular to the wafer, The amount of the chemical solution supplied during the treatment is four or more times greater than the amount of the chemical solution supplied at the end of the treatment. Anti-drip mechanism.

2. 2. The drip prevention mechanism according to claim 1, wherein the length of the straight body portion is at least twice the diameter of the drip opening.

3. 2. The drip prevention mechanism according to claim 1, wherein the straight-body nozzle body is a straight-body nozzle body in which the drip opening is connected flush with the straight-body portion, and the inner diameter of the straight-body nozzle body is 1 / 4 inch or less.

4. 2. The drip prevention mechanism according to claim 1, wherein the wafer has a diameter of 12 inches or more.

5. 2. The mechanism for preventing liquid dripping according to claim 1, wherein the drip nozzle is a plurality of drip nozzles, and a different chemical solution is dripped onto the wafer from each drip nozzle to perform chemical processing.

6. 2. The mechanism for preventing liquid dripping according to claim 1, wherein the chemical liquid is an etching liquid, and the amount of the chemical liquid supplied during processing is such that an etching rate of the wafer is 13,000 Å / min or more.

7. A gravity suck-back mechanism is provided for sucking the liquid remaining in the straight body portion after the supply of the liquid is stopped, The self-weight suck-back mechanism is A pipe made of a chemical-resistant resin and connected to a curved portion formed at an upper portion of the straight nozzle body; a liquid recovery opening connected to the piping; a liquid recovery nozzle body in which the liquid recovery opening is disposed at a position lower than the dripping opening; Including, The drip prevention mechanism according to claim 1.

8. an opening / closing valve is provided on the liquid recovery nozzle body, 8. The drip prevention mechanism according to claim 7, further comprising a chemical liquid refreshing mechanism configured to drain the chemical liquid remaining in the curved portion and the piping by opening the on-off valve.

9. A method for preventing dripping of a drip nozzle of a spin processing device using the dripping prevention mechanism according to any one of claims 1 to 8, supplying the chemical to the drip nozzle at a chemical processing supply amount during chemical processing of the wafer; supplying the chemical at a chemical end supply amount at the end of the chemical processing of the wafer; a step of stopping the supply of the chemical solution supplied at the chemical solution end supply amount; Including, The amount of the chemical solution supplied during the treatment is four or more times greater than the amount of the chemical solution supplied at the end of the treatment. How to prevent dripping.

10. 10. The method for preventing liquid dripping according to claim 9, wherein the chemical liquid is an etching liquid, and the amount of the chemical liquid supplied during the chemical treatment is such that an etching rate of the wafer is 13000 Å / min or more.

11. A method for preventing dripping of a drip nozzle of a spin processing device using the dripping prevention mechanism according to claim 7 or 8, supplying the chemical to the drip nozzle at a chemical processing supply amount during chemical processing of the wafer; supplying the chemical at a chemical end supply amount at the end of the chemical processing of the wafer; a step of stopping the supply of the chemical solution supplied at the chemical solution end supply amount; a suck-back process of sucking the chemical solution remaining in the straight body portion after the chemical solution supply is stopped after the stopping process; Including, The amount of the chemical solution supplied during the treatment is four or more times greater than the amount of the chemical solution supplied at the end of the treatment. How to prevent dripping.

12. 9. A spin processing apparatus incorporating the drip prevention mechanism according to claim 1, wherein the spin processing apparatus performs chemical processing by dripping a chemical onto a wafer placed thereon.

13. The spin processing apparatus of claim 12, wherein the wafer is a wafer having a diameter of 12 inches or more.

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