JP4390628B2 - Substrate processing apparatus and processing method thereof - Google Patents

Description

  The present invention relates to a substrate processing apparatus for processing a semiconductor substrate (hereinafter referred to as “wafer”). Specifically, while spreading a chemical solution dropped onto a wafer held on a wafer chuck by rotation of the wafer chuck, The present invention relates to a substrate processing apparatus and a processing method for performing a predetermined process.

  Substrate processing apparatuses used in semiconductor device manufacturing processes include a photoresist coating apparatus, a developing apparatus, a cleaning apparatus, an etching apparatus, and the like, which are disclosed in, for example, Japanese Patent Laid-Open No. 10-137664 (Patent Document 1). Yes.

  FIG. 4 is a cross-sectional view showing a configuration of a conventional substrate processing apparatus. A conventional substrate processing apparatus 41 shown in FIG. 4 supplies a chemical solution to the wafer W above the wafer chuck 42, a wafer chuck 42 that holds and rotates the wafer W, a cup 43 that accommodates the wafer chuck 42. A chemical supply nozzle 44 is provided. Further, the wafer chuck 42 is horizontally fixed to the tip end of the rotating shaft 46 connected to the motor 45 and is driven to rotate. Further, a plurality of support pins 47 and holding pins 48 that support the back surface of the wafer W are provided on the upper surface of the wafer chuck 42.

  A rotating shaft 46 of the motor 45 is formed of a hollow body, and a back rinse nozzle 49 for back surface cleaning is inserted therein, and penetrates the wafer chuck 42 and protrudes toward the back surface side of the wafer W. The rotary shaft 46 and the back rinse nozzle 49 are fixed by nozzle fixing jigs 50a and 50b including bearings and the like. A cap 51 is attached to the upper portion of the back rinse nozzle 49 in order to prevent the rinse liquid supplied from the back rinse nozzle 49 from entering the inside of the rotary shaft 46. A drain port 52 for discharging the scattered chemical liquid is provided at the bottom of the cup 43, and a rinse liquid supply unit 53 for supplying a rinse liquid such as pure water is connected to the back rinse nozzle 49.

  Next, the operation of this conventional substrate processing apparatus 41 will be described. First, the wafer W is placed on the wafer chuck 42 and horizontally fixed by the support pins 47 and the holding pins 48, and then the chemical solution supply nozzle 44 is moved above the center of the wafer W while the wafer W is rotationally driven. Next, a chemical solution is supplied from the chemical solution supply nozzle 44 to the surface of the wafer W for a predetermined time. At this time, the chemical liquid spread on the surface of the wafer W is discharged from the liquid discharge port 51 by centrifugal force, but partially passes through the holding pins 48 and the support pins 47 and also wraps around and adheres to the back surface of the wafer W. .

In order to remove the chemical solution adhering to the back surface of the wafer W, a rinse liquid such as pure water is supplied from the front end of the back rinse nozzle 49 from the rinse liquid supply unit 53 to the center of the back surface of the wafer W. The rinse liquid supplied to the center of the back surface of the wafer W flows outward along the back surface of the wafer W due to centrifugal force, is swung outward from the outer peripheral portion of the wafer W, and is discharged from the drain port 52. Thereby, the whole back surface of the wafer W can be uniformly cleaned with the rinse liquid.
JP-A-10-137664 (pages 2 and 3, paragraphs 0002 to 0010, FIG. 6)

  However, the above-described conventional substrate processing apparatus 41 has the following problems.

  The back rinse nozzle 49 provided in the rotary shaft 46 is fixed to the rotary shaft 46 by nozzle fixing jigs 50a and 50b. However, since the diameter is small and light, the wafer chuck 42 and the rotary shaft 46 rotate at high speed. There was a problem that it was easy to be eccentric due to vibrations. When the back rinse nozzle 49 is eccentric, the back rinse nozzle 49 comes into contact with the wafer chuck 42 and the rotating shaft 49 to generate foreign matter such as SUS dust. When the foreign matter adheres to the back surface of the wafer W, the height of the wafer W varies, which causes a pattern failure due to a defocus state in the photolithography process. Further, when the foreign matter adheres to the surface of the wafer W, it becomes a defect, which deteriorates the quality and yield of the product.

  Further, in order to reduce the eccentricity of the back rinse nozzle 49 as much as possible even when the wafer chuck 42 and the rotation shaft 46 vibrate, it is necessary to attach the back rinse nozzle 49 to the central portion of the rotation shaft 46 with high accuracy. The number of man-hours for adjustment has also increased, which has been the cause of reduced equipment availability and productivity.

  The present invention has been conceived in order to solve the above-described problems, and an object thereof is to provide a substrate processing apparatus having a function capable of greatly reducing the number of foreign matters adhering to a wafer with a simple configuration and a processing method therefor. And

In order to achieve the above object, a substrate processing apparatus according to claim 1 of the present invention mounts a semiconductor substrate on a wafer chuck fixed to the tip of a rotating shaft, and supplies a chemical solution while rotating the semiconductor substrate. And a substrate processing apparatus for cleaning a back surface of the semiconductor substrate by supplying a rinsing liquid from a back rinse nozzle provided inside the rotary shaft, wherein the back rinse nozzle includes a double pipe composed of an inner tube and an outer tube. Constituting with a pipe, connecting a rinsing liquid supply means to the inner pipe, connecting a decompression means to the outer pipe, and making the position of the opening of the inner pipe higher than the position of the opening of the outer pipe, A cap that covers the outer tube is provided at the tip of the inner tube so as to cover the upper portion of the opening of the outer tube so that the rinse liquid supplied from the back rinse nozzle does not enter the inside of the outer tube. It is characterized by .

The substrate processing method according to claim 8, the semiconductor substrate is placed on is fixed to the tip of the rotary shaft wafer chuck, after supplying the drug solution while rotating the semiconductor substrate, provided inside of said rotary shaft A substrate processing method for cleaning a back surface of the semiconductor substrate by supplying a rinsing liquid from a back rinse nozzle, wherein the position of the opening of the back rinse nozzle is higher than the position of the opening of the outer tube and the outer tube The inner pipe is formed of a double pipe made of an inner pipe, and covers the upper part of the opening of the outer pipe so that the rinse liquid supplied from the inner pipe does not enter the outer pipe. A cap is provided at the tip, and suction is performed from the outer tube while supplying a rinsing liquid from the inner tube.

In the substrate processing method according to claim 9 , the semiconductor substrate is placed on a wafer chuck fixed to the tip of the rotating shaft, and the chemical solution is supplied while rotating the semiconductor substrate, and then provided inside the rotating shaft. obtained by supplying a rinsing liquid from the back rinse nozzle the substrate processing method of cleaning a back surface of the semiconductor substrate, formed of a double tube consisting of a pre-Symbol rotation axis together the inner tube and the outer tube, the back rinse The nozzle is composed of a double pipe composed of an outer pipe and an inner pipe whose opening is higher than the position of the opening of the outer pipe, and is inserted into the inner pipe of the rotating shaft, and the back rinse nozzle The tip of the inner tube of the back rinse nozzle so as to cover the upper part of the opening of the outer tube of the back rinse nozzle so that the rinse liquid supplied from the inner tube does not enter the inside of the outer tube of the back rinse nozzle Part Cap is provided, while supplying rinsing liquid and gas from the outer tube of the tube and the rotation axis of the back rinse nozzle, and performs suction from the outer tube of the back rinse nozzle.

  As described above, according to the substrate processing apparatus and the processing method thereof of the present invention, the back rinse nozzle has a double tube structure including an inner tube and an outer tube, and at the same time when the rinse liquid is supplied from the inner tube to the wafer. Since foreign matter generated from the outer tube is sucked, even if the back rinse nozzle is decentered due to vibration of the wafer chuck and foreign matter is generated, adhesion to the wafer can be effectively prevented. Thereby, the wafer can be processed stably, and the quality and yield of the product can be improved.

  Also, the rotating shaft has a double tube structure of an inner tube and an outer tube, and when gas is supplied from the outer tube of the rotating shaft, it is sucked from the outer tube of the back rinse nozzle at the same time. The generated foreign matter can be removed by suction without disturbing the airflow. Thereby, the wafer can be processed more stably, and the quality and yield of the product can be improved.

  Further, since the ring portion surrounding the opening of the rotating shaft is provided on the upper surface of the wafer chuck, it is possible to obtain a greater effect in preventing the rinsing liquid from entering the rotating shaft and preventing foreign matter from adhering to the wafer. In addition, since at least three nozzle fixing jigs for fixing the back rinse nozzle to the inside of the rotation shaft are provided, the eccentricity of the back rinse nozzle can be further effectively suppressed. As a result, the accuracy of attaching the back rinse nozzle to the rotating shaft can be increased, the number of work steps can be reduced, and the apparatus operating rate and productivity can be improved.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1A is a sectional view showing the configuration of the substrate processing apparatus according to the first embodiment of the present invention, and FIG. 1B is a plan view of the wafer chuck shown in FIG.

  A substrate processing apparatus 1 according to this embodiment shown in FIGS. 1A and 1B includes a wafer chuck 2 that holds and rotates a wafer W, a cup 3 that houses the wafer chuck 2, and a wafer chuck 2. There is provided a chemical supply nozzle 4 for supplying a chemical to the wafer W. Further, the wafer chuck 2 is horizontally fixed to the tip of the rotating shaft 6 connected to the motor 5 and is driven to rotate. Further, a plurality of support pins 7 and holding pins 8 that support the back surface of the wafer W are provided on the upper surface of the wafer chuck 2.

  A rotating shaft 6 of the motor 5 is formed of a hollow body, and a back rinse nozzle 9 for back surface cleaning is inserted therein, and penetrates the wafer chuck 2 and protrudes toward the back surface side of the wafer W. The rotating shaft 6 and the back rinse nozzle 9 are fixed by nozzle fixing jigs 10a and 10b including bearings and the like. A cap 11 is attached to the upper portion of the back rinse nozzle 9 in order to prevent the rinse liquid supplied from the back rinse nozzle 9 from entering the rotary shaft 6. Further, a drainage port 12 for discharging the scattered chemical liquid is provided at the bottom of the cup 3.

  Further, in the substrate processing apparatus 1 of the present embodiment, the back rinse nozzle 9 is constituted by a double pipe including a nozzle inner pipe 9a and a nozzle outer pipe 9b, and the nozzle inner pipe 9a is a rinse for supplying a rinse liquid such as pure water. Connected to the liquid supply unit 13, the nozzle outer tube 9 b is connected to the decompression unit 14. The decompression unit 14 can use a small and inexpensive convam (registered trademark, a vacuum generator using a gas exhaust flow rate).

  Next, the operation of the substrate processing apparatus 1 of this embodiment will be described. First, the wafer W is placed on the wafer chuck 2 and horizontally fixed by the support pins 7 and the holding pins 8, and then the chemical solution supply nozzle 4 is moved above the center of the wafer W while the wafer W is rotationally driven. Next, the chemical solution is supplied from the chemical solution supply nozzle 4 to the surface of the wafer W for a predetermined time. At this time, the chemical spread on the surface of the wafer W is discharged from the liquid discharge port 11 by centrifugal force, but partially passes through the holding pins 8 and the support pins 7 and adheres to the back surface of the wafer W.

  In order to remove the chemical solution adhering to the back surface of the wafer W, a rinse liquid such as pure water is supplied from the inner tube 9a of the back rinse nozzle 9 from the rinse liquid supply unit 13 to the center of the back surface of the wafer W. The rinse liquid supplied to the center of the back surface of the wafer W flows outward along the back surface of the wafer W by centrifugal force, is swung outward from the outer peripheral portion of the wafer W, and is discharged from the drain port 12. Thereby, the whole back surface of the wafer W can be uniformly cleaned with the rinse liquid.

  Furthermore, the substrate processing apparatus 1 of the present embodiment performs suction from the nozzle outer tube 9b at the same time when supplying the rinsing liquid from the nozzle inner tube 9a of the back rinse nozzle 9 to the wafer W. Since the nozzle outer tube 9b has been depressurized to a predetermined value by the depressurization unit 14, the foreign matter such as SUS dust generated by contacting the wafer chuck 2 and the rotating shaft 6 due to the eccentricity of the back rinse nozzle 9 is efficiently sucked. It is possible to prevent foreign matter from adhering to the wafer W. The height of the nozzle inner tube 9a of the back rinse nozzle 9 is set to be higher than that of the nozzle outer tube 9b, and a cap 11 that covers the nozzle outer tube 9b is attached to the tip of the nozzle inner tube 9a. Therefore, the rinse liquid supplied from the nozzle inner tube 9a is discharged from the liquid discharge port 12 without entering the nozzle outer tube 9b. Therefore, when cleaning the back surface of the wafer W, foreign matters can be stably removed from the nozzle outer tube 9b.

  In this embodiment, the case where the foreign matter is sucked and removed when the back surface of the wafer W is cleaned has been described. However, when the chemical solution is supplied to the surface of the wafer W, the foreign matter is sucked and removed in the same manner. May be.

  Next, another preferred embodiment will be described with reference to the drawings. FIG. 2A is a sectional view showing the configuration of the substrate processing apparatus according to the second embodiment of the present invention, and FIG. 2B is a plan view of the wafer chuck shown in FIG. In FIGS. 2A and 2B, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  In the substrate processing apparatus 21 of this embodiment shown in FIGS. 2A and 2B, the difference from the first embodiment described above is that the rotating shaft 22 for rotating the wafer chuck 2 is provided with an inner tube 22a and an outer tube 22b. The back rinse nozzle 9 is inserted into the inner tube 22 a and the outer tube 22 b is connected to the gas supply unit 23. From the gas supply unit 23, a gas composed of air, nitrogen, argon, helium or a mixed gas thereof is supplied to the lower part of the cap 11 through the outer tube 22 b of the rotating shaft 22.

  Next, the operation of the substrate processing apparatus 21 of this embodiment will be described. After chemical treatment of the wafer W by the chemical solution supply nozzle 4 for a predetermined time, in order to remove the chemical solution adhering to the back surface of the wafer W, a rinse solution such as pure water is removed from the nozzle inner tube 9a of the back rinse nozzle 9 on the wafer W. Supply to the center of the back side. At this time, gas is simultaneously supplied from the outer tube 22b of the rotating shaft 22 to the gap between the cap 11 and the wafer chuck 2, and suction is performed from the nozzle outer tube 9b. As described above, since an air flow is formed from the outside to the inside, the back rinse nozzle 9 sucks and removes the foreign matters generated by contacting the wafer chuck 2 and the rotating shaft 6 more effectively without diffusing outward. It is possible to effectively prevent foreign matter from adhering to the wafer W. At this time, since the gas supply amount and the suction amount are set to be substantially equal, the substrate can be processed stably without disturbing the atmosphere in the substrate processing apparatus 21. Such a configuration has a great effect particularly in a photoresist coating apparatus that requires stable film thickness control and mist prevention.

  Next, another preferred embodiment will be described with reference to the drawings. FIG. 3A is a sectional view showing the configuration of the substrate processing apparatus according to the third embodiment of the present invention, and FIG. 3B is a plan view of the wafer chuck shown in FIG. In FIGS. 3A and 3B, the same components as those in the second embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the substrate processing apparatus 31 of this embodiment shown in FIGS. 3A and 3B, the difference from the second embodiment described above is that a ring is formed so as to surround the opening of the rotating shaft 22 on the upper surface of the wafer chuck 2. In addition to providing the portion 32, the back rinse nozzle 9 is fixed to the rotating shaft 22 by at least three nozzle fixing jigs 33a to 33c. Further, the diameter of the ring portion 32 is set to be smaller than the diameter of the bottom surface of the cap 11, and the height of the ring portion 32 is set to be lower than the height of the bottom surface of the cap 11. Further, the nozzle fixing jigs 33 a to 33 c are provided in the tip end portion, the center portion, and the motor 5 inside the back rinse nozzle 9, respectively.

  Next, the operation of the substrate processing apparatus 31 of this embodiment will be described. After chemical treatment of the wafer W by the chemical solution supply nozzle 4 for a predetermined time, in order to remove the chemical solution adhering to the back surface of the wafer W, a rinse solution such as pure water is removed from the nozzle inner tube 9a of the back rinse nozzle 9 on the wafer W. Supply to the center of the back side. At this time, gas is simultaneously supplied from the outer tube 22b of the rotating shaft 22 to the gap between the cap 11 and the wafer chuck 2, and suction is performed from the nozzle outer tube 9b.

  In the substrate processing apparatus 31 of the present embodiment, since the ring portion 32 is provided at a position below the cap 11 on the upper surface of the wafer chuck 2, the series of operations of gas supply and suction described above are performed in the wafer chuck 2 and the cap 11. And it can carry out efficiently within the area | region enclosed by the ring part 32. FIG. In the past, the cap 11 alone was used to prevent the rinsing liquid from entering the rotating shaft 22, but some of the rinsing liquid entered the rotating shaft 22 when the support pins 7 and the holding pins 8 rebound. That could not be prevented. The ring portion 32 of the present embodiment can also reliably prevent the inside of the rotating shaft 22 from entering due to the boiled rinse liquid.

  Further, since the outer peripheral portion of the back rinse nozzle 9 is fixed to the rotating shaft 22 by the three nozzle fixing jigs 33a to 33c, the eccentricity of the back rinse nozzle 9 is further effectively suppressed, and foreign matter is generated. The amount can be greatly reduced. In addition, the number of work steps for positioning the center of the back rinse nozzle 9 can be simplified.

  Thus, in the substrate processing apparatus 31 of the present embodiment, the ring portion 32 is newly provided on the upper surface of the wafer chuck 2 and the nozzle fixing jigs 33a to 33c for fixing the back rinse nozzle 9 are additionally provided. The present invention is very effective in reducing the vibration of the back rinse nozzle 9, preventing the rinsing liquid from entering the rotary shaft 22, preventing diffusion of foreign matter generated by contact between the back rinse nozzle 9, the wafer chuck 2, and the rotary shaft 22. Thereby, substrate processing can be performed stably.

  In the above embodiment, the case where the three nozzle fixing jigs 33a to 33c are provided has been described. However, the present invention is not limited to this, and four or more nozzle fixing jigs may be provided. Further, if these plural nozzle fixing jigs are connected to each other, the eccentricity of the back rinse nozzle 9 can be prevented more reliably, and the mounting accuracy of the back rinse nozzle can be improved.

  Furthermore, the substrate processing apparatus of the present invention can be applied to any apparatus as long as it has a mechanism for cleaning the back surface after the front surface of the wafer is processed with a chemical solution, for example, a photoresist coating apparatus, a developing apparatus, and a cleaning apparatus. It can be applied to an etching apparatus or the like.

  The back rinse nozzle has a double tube structure consisting of an inner tube and an outer tube, and when supplying the rinse liquid from the inner tube to the wafer, the back rinse nozzle is vibrated by the vibration of the wafer chuck by simultaneously sucking out foreign matter generated from the outer tube. Even if decentering occurs and foreign matter is generated, adhesion to the wafer can be effectively prevented. Thereby, the wafer can be processed stably, and the quality and yield of the product can be improved.

  Also, the rotating shaft has a double tube structure of an inner tube and an outer tube, and when gas is supplied from the outer tube of the rotating shaft, the air flow in the substrate processing apparatus is sucked from the outer tube of the back rinse nozzle at the same time. The generated foreign matter can be removed by suction without being disturbed. Thereby, the wafer can be processed more stably, and the quality and yield of the product can be improved.

Sectional drawing of the substrate processing apparatus of 1st Example of this invention, and the top view of a wafer chuck | zipper Sectional drawing of the substrate processing apparatus of 2nd Example of this invention, and top view of a wafer chuck | zipper Sectional drawing of the substrate processing apparatus of 3rd Example of this invention, and top view of a wafer chuck | zipper Sectional view of a conventional substrate processing apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus of 1st Example of this invention 2 Wafer chuck 3 Cup 4 Chemical solution supply nozzle 5 Motor 6 Rotating shaft 7 Support pin 8 Holding pin 9 Back rinse nozzle 9a Nozzle inner tube 9b Nozzle outer tube 10a, 10b Nozzle fixing treatment Tool 11 Cap 12 Drainage port 13 Rinse solution supply unit 14 Decompression unit 21 Substrate processing apparatus of the second embodiment of the present invention 22 Rotating shaft 22a Inner tube 22b Outer tube 23 Gas supply unit 31 Substrate of the third embodiment of the present invention Processing device 32 Ring portion 33a to 33c Nozzle fixing jig 41 Conventional substrate processing device 42 Wafer chuck 43 Cup 44 Chemical solution supply nozzle 45 Motor 46 Rotating shaft 47 Support pin 48 Holding pin 49 Back rinse nozzle 50a, 50b Nozzle fixing jig 51 Cap 52 Drainage port

Claims (9)

A semiconductor substrate is placed on a wafer chuck fixed to the tip of the rotating shaft, and a chemical solution is supplied while rotating the semiconductor substrate, and then a rinsing solution is supplied from a back rinse nozzle provided inside the rotating shaft. In the substrate processing apparatus for cleaning the back surface of the semiconductor substrate,
The back rinse nozzle is composed of a double pipe consisting of an inner pipe and an outer pipe,
The position of the opening portion of the inner tube as well as higher than the position of the opening of the outer tube, the caps provided at the distal end portion of the inner tube,
A rinse liquid supply means is connected to the inner pipe;
Connecting a decompression means to the outer tube,
The substrate processing apparatus , wherein the cap is provided so as to cover an upper portion of the opening of the outer tube so that the rinse liquid supplied from the inner tube does not enter the inside of the outer tube . The rotating shaft is a double tube of an inner tube and an outer tube,
The back rinse nozzle is inserted into the inner tube of the rotating shaft,
Claim 1 Symbol mounting substrate processing apparatus is characterized in that connecting the gas supply means to the outer tube. 3. The substrate processing apparatus according to claim 2, wherein the gas supplied from the gas supply means is made of air, nitrogen, argon, helium or a mixed gas thereof. The upper surface of the wafer chuck, a substrate processing apparatus according to any one of claims 1 to 3, characterized in that a ring portion surrounding the opening portion of the rotary shaft.
The substrate processing apparatus according to claim 4, wherein a diameter of the ring portion is smaller than a diameter of a bottom surface of the cap, and a height of the ring portion is lower than a height of the bottom surface of the cap.
The substrate processing apparatus according to any one of claims 1 to 5, characterized in that the nozzle fixing means for fixing the back rinse nozzle to the rotation the shaft is provided at least three or more. The substrate processing apparatus according to claim 6 , wherein the nozzle fixing means are connected to each other. A semiconductor substrate is placed on a wafer chuck fixed to the tip of the rotating shaft, and a chemical solution is supplied while rotating the semiconductor substrate, and then a rinsing solution is supplied from a back rinse nozzle provided inside the rotating shaft. In the substrate processing method for cleaning the back surface of the semiconductor substrate,
The back rinse nozzle is composed of a double pipe consisting of an outer pipe and an inner pipe whose position of the opening is higher than the position of the opening of the outer pipe ,
A cap is provided at the tip of the inner tube so as to cover the upper part of the opening of the outer tube so that the rinse liquid does not enter the inside of the outer tube,
A substrate processing method, wherein suction is performed from the outer tube while supplying a rinsing liquid from the inner tube. A semiconductor substrate is mounted on a wafer chuck fixed to the tip of the rotating shaft, and after supplying the chemical liquid while rotating the semiconductor substrate, a rinsing liquid is supplied from a back rinse nozzle provided inside the rotating shaft. In the substrate processing method for cleaning the back surface of the semiconductor substrate,
Before Symbol rotary shaft is constituted by a double pipe consisting of an inner tube and the outer tube,
The back rinse nozzle is composed of a double pipe composed of an outer pipe and an inner pipe whose opening is higher than the position of the opening of the outer pipe, and is inserted into the inner pipe of the rotating shaft,
A cap is provided at the tip of the inner tube of the back rinse nozzle so as to cover the upper portion of the opening of the outer tube of the back rinse nozzle so that the rinse liquid does not enter the inside of the outer tube of the back rinse nozzle. ,
2. A substrate processing method, wherein suction is performed from an outer tube of the back rinse nozzle while supplying a rinse liquid and a gas from an inner tube of the back rinse nozzle and an outer tube of the rotating shaft.

Images