JP4421967B2 - Substrate processing apparatus and substrate processing method - Google Patents

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for cleaning a substrate such as a semiconductor wafer.

  In the manufacturing process of a semiconductor device, various cleaning apparatuses for cleaning a semiconductor wafer (hereinafter referred to as “wafer”) are used. As an example of the cleaning process, the wafer is immersed in a processing tank in which a chemical solution such as diluted hydrofluoric acid (DHF) is stored, and the wafer is rinsed with pure water, and then the wafer is treated with isopropyl alcohol (IPA The process of spraying the vapor | steam etc. of) and performing a drying process is performed.

  As an apparatus for performing such a wafer cleaning process, a treatment tank for performing a chemical or pure water treatment is disposed below a chamber whose upper part can be opened and closed by a lid, and a drying processing unit for performing a drying process is provided on the upper side. In addition, there is known one in which a shutter is provided between the processing tank and the drying processing unit so as to be freely opened and closed (see, for example, Patent Document 1). In such an apparatus, first, the upper part of the chamber is opened, the shutter is opened, the wafer is passed through the drying processing unit in the chamber and lowered into the processing tank, and the upper part of the chamber is closed by the lid, Chemical solution processing is performed in the processing tank. Thereafter, the wafer is pulled up into the drying processing unit, the shutter is closed, the atmosphere of the drying processing unit and the processing tank is separated, and the wafer is dried by supplying IPA vapor and nitrogen gas. Then, after the inside of the chamber is purged with nitrogen gas before unloading the wafer, the lid is opened and the wafer is unloaded.

  Here, when the wafer is dried in the drying processing unit, pure water or liquefied IPA falls from the wafer onto the shutter. When liquid accumulates on the shutter, it falls into the processing tank and contaminates the chemicals, etc., contaminates the interior of the chamber, and further contaminates the wafer. It is necessary to remove everything. For this reason, a drainage port is provided at the center of the shutter, and a vacuum pump is attached to the drainage port, and when the shutter is closed, the suction and removal of the liquid on the upper surface of the shutter is started immediately.

However, in such a liquid removing method from the upper surface of the shutter, a large amount of air is taken in from the drainage port, so that a liquid residue is generated on the shutter. If a vacuum pump is used, there is pulsation, and suction cannot be performed constantly. In recent years, with the progress of miniaturization of structures in semiconductor devices, these may become problems.
JP 2000-55543 A

  The present invention has been made in view of such circumstances, and includes a liquid processing unit at a lower portion, a drying processing unit thereon, and a shutter between the liquid processing unit and the drying processing unit can be freely opened and closed. It is an object of the present invention to provide a substrate processing apparatus that reduces the amount of liquid remaining on the shutter. The present invention also provides a substrate processing method for reducing liquid residue on the shutter.

According to the present invention, a liquid processing unit for processing a substrate with a processing liquid;
A drying processing unit provided on the liquid processing unit and drying the substrate;
A substrate transfer device for transferring a substrate between the liquid processing unit and the drying processing unit;
A shutter that is movable in a horizontal direction so as to be able to open and close between the liquid processing unit and the drying processing unit, and has a drain port formed therein;
A suction mechanism connected to the drainage port;
A suction control member that is provided on the opening of the drainage port and generates a fluid flow that flows along the upper surface of the shutter and flows into the drainage port when the suction mechanism is operated;
A substrate processing apparatus is provided.

In this substrate processing apparatus, it is preferable that the drainage port is formed substantially at the center of the shutter. Further, a substantially conical shape is preferably used as the suction control member so that the liquid falling from the substrate onto the suction control member does not remain on the suction control member. The gap formed between the outer peripheral end of the substantially conical suction control member and the upper surface of the shutter (that is, the height of the opening) is preferably 0.5 mm or more and 1.0 mm or less. The opening diameter of the drainage port is preferably shorter than the outer diameter of the substantially conical suction control member. If the upper surface of the shutter is a substantially conical concave surface and the drainage port is provided at the deepest portion of the concave surface, the liquid remaining on the shutter can be further reduced. An aspirator is preferably used as the suction mechanism. Thereby, a constant suction is possible.

  The substrate processing apparatus preferably further includes a processing gas supply mechanism that supplies a processing gas to the drying processing unit and a control device that controls the operation of the substrate processing apparatus. The control device starts supplying the processing gas to the drying processing unit, starts draining from the drain port provided in the shutter after a predetermined time has elapsed, and then stops supplying the processing gas after the predetermined time has elapsed. Then, the processing gas supply mechanism and the suction mechanism are controlled so as to stop the drainage from the drainage port.

  The substrate processing apparatus further includes an inert gas supply mechanism that supplies an inert gas to the drying processing unit, and the control device supplies the drying processing unit to the drying processing unit substantially simultaneously with the start of supply of the processing gas to the drying processing unit. It is preferable that the inert gas supply mechanism is controlled so that the supply of the inert gas is stopped after the supply of the inert gas is started and the drainage from the drainage port is stopped. As a preferred embodiment of the substrate processing apparatus of the present invention, the substrate is subjected to chemical treatment of the substrate in the liquid treatment section, and water washing treatment following the chemical treatment, and the substrate after the water washing treatment is treated with isopropyl alcohol vapor and inert gas in the drying treatment section. Examples include a drying apparatus.

According to the invention, there is provided a substrate processing method by the substrate processing apparatus, that is, a step of liquid processing a substrate in a liquid processing section that processes the substrate with a predetermined processing liquid;
A step of pulling up the substrate after the liquid processing to a drying processing unit provided above the liquid processing unit;
Isolating the liquid processing unit and the drying processing unit with a shutter;
Drying the substrate in the drying processing unit,
The substrate drying process includes:
Starting the supply of processing gas to the drying processing unit;
After a lapse of a certain time from the start of the supply of the processing gas, the drainage liquid flows along the upper surface of the shutter using a suction control member provided on an opening of a drainage port provided in the shutter. Generating a fluid flow flowing into the mouth, and starting suction and drainage of the liquid dropped on the shutter through the drainage port;
A step of stopping the supply of the processing gas after elapse of a predetermined time after starting drainage from the drainage port;
A step of stopping suction and drainage from the drainage port after a lapse of a predetermined time after stopping the supply of the processing gas;
There is provided a substrate processing method characterized by comprising:

  According to the present invention, it is possible to reduce the liquid residue on the shutter that partitions the liquid processing unit and the drying processing unit. Thereby, contamination of the apparatus and the substrate to be processed can be prevented.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Here, for example, a description will be given by taking as an example a cleaning processing apparatus that batch-processes 50 semiconductor wafers (hereinafter referred to as “wafers”) and further performs a drying process.

  FIG. 1 is a sectional view showing a schematic structure of the cleaning processing apparatus 1. The cleaning processing apparatus 1 performs liquid processing on the wafer W (here, liquid processing using a dilute hydrofluoric acid aqueous solution (DHF) and subsequent rinsing processing using pure water (DIW)) is performed. Between the liquid processing unit 2 and the drying processing unit 3, which is disposed above the liquid processing unit 2 and which dries the wafer W that has been rinsed in the liquid processing unit 2. A wafer guide 4 is provided as a moving mechanism for moving 50 wafers W at a time.

  The wafer guide 4 supports, for example, a holding unit 26 that can hold 50 wafers W in a substantially vertical posture and arranged in a direction perpendicular to the paper surface of FIG. The column part 27 penetrates a lid 62 of the chamber 5 described later in an airtight manner. The support column 27 can be moved up and down by a guide lifting mechanism 28, and the wafer W held by the holding unit 26 can be moved between the liquid processing unit 2 and the drying processing unit 3.

  The liquid processing unit 2 and the drying processing unit 3 can be freely opened and closed by a shutter 10, and this shutter 10 is used when performing liquid processing in the liquid processing unit 2 and between the liquid processing unit 2 and the drying processing unit 3. When the wafer W is moved, it is accommodated in the shutter box 11. Clean air is down-flowed from the fan filter unit (FFU) 12 provided above the cleaning processing apparatus 5.

  In the liquid processing unit 2, DHF and DIW are stored, an inner tank 30 that stores the wafer W and performs liquid processing, an intermediate tank 31 that is formed so as to surround an opening in the upper part of the inner tank 30, and an intermediate tank 31. The liquid processing tank 6 having an outer tank 32 formed so as to surround the opening of the liquid processing tank 6 is disposed, and the liquid processing tank 6 is disposed in the box 13.

  A processing liquid supply nozzle 35 for discharging DHF and DIW into the inner tank 30 is provided at the lower part of the inner tank 30. The treatment liquid supply nozzle 35 includes a treatment liquid supply line 20 having a DHF supply line 51 for supplying DHF from the DHF supply source to the inner tank 30 and a DIW supply line 52 for supplying DIW from the DIW supply source. It is connected.

  By switching the opening / closing of the opening / closing valve 51a interposed in the DHF supply line 51 and the opening / closing valve 52a interposed in the DIW supply line 52, either DHF or DIW can be supplied. By adjusting the opening / closing amount of 52a, DHF can be diluted and supplied to the inner tank 30. Alternatively, a constant concentration of DHF may be prepared in the inner tank 30 by supplying DIW to the inner tank 30 first and then supplying DHF. A concentration sensor 53 for measuring the DHF concentration is provided in the inner tank 30.

  A drain pipe 36 with an open / close valve 37 interposed is connected to the bottom of the inner tank 30. By opening the open / close valve 37, DHF and DIW can be discharged from the inner tank 30 into the box 13. It can be done. In addition, a drain pipe 141 with a valve interposed is provided at the bottom of the box 13 so that DHF and DIW can be discharged from the box 13. Further, the box 13 is provided with an exhaust pipe 142. For example, when DHF is stored in the box 13, steam generated from the DHF can be exhausted.

  The middle tank 31 receives pure water that has overflowed from the upper surface opening of the inner tank 30. The middle tank 31 is provided with a drain pipe 41 for discharging pure water from the middle tank 31, and a trap 42 is connected to the drain pipe 41. In this trap 42, the treatment liquid discharged through the drainage pipe 41 is stored at a constant height, and the treatment liquid is discharged from the trap 42 through the drainage pipe 43 opened on the water surface. The lower end (drainage port) of the drainage pipe 43 is disposed at a position lower than the upper end (drainage port) of the drainage pipe 43. With such a configuration, the atmosphere of the drainage pipe 43 and the box 13 can be prevented from flowing into the drainage pipe 41. For example, when DHF is stored in the inner tank 30 and the wafer W is immersed and processed, and then DIW is supplied into the inner tank 30 and the wafer W is rinsed, the wafer W is discharged into the box 13. Further, the vapor generated from the DHF is prevented from being mixed into the liquid processing tank 6 through the drain pipe 41.

  Pure water is always stored in the outer tub 32, and the annular seal plate 46 is immersed in the pure water at the lower portion, and the upper end of the shutter box 11 is disposed above the outer tub 32. It arrange | positions so that it may closely_contact | adhere to the lower board. With such a configuration, the outer tub 32 has a sealing function using pure water and does not leak the atmosphere of the inner tub 30 to the outside. The shutter box 11 is provided with an exhaust pipe 136 with an opening / closing valve 137 interposed therebetween, so that the atmosphere in the shutter box 11 can be exhausted.

  FIG. 2 is a cross-sectional view showing a more detailed configuration of the drying processing unit 3 and the shutter 10. The drying processing unit 3 is provided with a chamber 5 for accommodating the wafer W. The chamber 5 includes a substantially cylindrical main body 61 and a lid 62 for opening and closing the upper surface opening 61 a of the main body 61. Has been. The lower surface opening 61 b of the main body 61 is airtightly connected to an opening formed in the upper plate of the shutter box 11. Further, in a state where the shutter 10 is disposed directly below the main body 61, the lower surface opening 61 b is airtightly closed by the seal ring 135 provided on the upper surface of the shutter 10 coming into contact with the lower end of the main body 61.

  The lid 62 has a substantially semicircular shape in cross section, and is arranged so that the bottom part is on the upper side. The lid 62 can be raised and lowered by a lid raising / lowering mechanism 64, can be stopped at positions P1, P2, and P3 shown in FIG. 2, and can be moved between these positions. The wafer between the outside of the cleaning processing apparatus 1 and the inside of the drying processing unit 3 (that is, the inside of the main body 61) with the lid 62 raised to the position P1 and the upper surface opening 61a of the main body 61 opened. W can be carried in and out. More specifically, the wafer W can be transferred between the holding unit 26 and an external transfer device (not shown) in a state where the holding unit 26 of the wafer guide 4 is extended above the main body 61.

  When the lid 62 is at the position P <b> 2, a certain gap is formed between the lower end of the lid 62 and the upper surface opening 61 a of the main body 61. As described above, when the lid 62 is at the position P1 and the position P2, the inside of the main body 61 communicates with the outside air. In a state where the lid 62 is disposed at the position P3, the lower end surface of the lid 62 comes into contact with the seal ring 63 provided at the upper end of the main body 61, and the upper surface opening 61a of the main body 61 is closed. At this time, the shutter 10 closes the lower surface opening 61b of the main body 61 so that the atmosphere in the main body 61 does not leak outside.

In the chamber 5, for example, a first gas that supplies a processing gas for drying made of isopropyl alcohol (IPA) vapor and nitrogen gas heated to a predetermined temperature (hereinafter referred to as “hot N ₂ ”) into the chamber 5. A supply nozzle 71 and a second gas supply nozzle 72 for supplying normal temperature nitrogen gas (hereinafter referred to as “normal temperature N ₂ ”) into the chamber 5 are disposed. In the chamber 5, an exhaust nozzle 73 is provided for exhausting the gas pushed out of the chamber 5 by supplying a processing gas or the like into the chamber 5. The exhaust nozzle 73 includes a forced exhaust line 48 to which a forced exhaust device (not shown) for forcibly exhausting atmospheric gas in the chamber 5 is attached, and a natural exhaust line for maintaining the interior of the chamber 5 at atmospheric pressure. 49 are connected.

A processing gas supply line 21 is connected to the first gas supply nozzle 71, and an IPA vapor generator 22 that generates IPA vapor is connected to the processing gas supply line 21. Further, the IPA steam generator 22 is connected to an IPA supply line 23 connected to an IPA supply source via an open / close valve 82, and to a hot N ₂ supply source via an open / close valve 83 and a flow meter 84. A hot N ₂ supply line 24 is connected. The second gas supply nozzle 72 is connected to a room temperature N ₂ supply line 25 that supplies room temperature N ₂ from a room temperature N ₂ supply source with an open / close valve 86 interposed.

The hot N ₂ supply line 24 and the processing gas supply line 21 may be configured so that the temperature of the hot N _{2 and} the temperature of the drying processing gas are not lowered by a heat insulating material or a heater (not shown). Drying process gas by the hot N ₂ supplied from the IPA and hot N ₂ supply line 24 supplied from the IPA supply line 23 is mixed in the IPA vapor generating apparatus 22 is prepared, drying process gas therein To the first gas supply nozzle 71. Also, only the hot N ₂ can be sent to the first gas supply nozzle 71 by closing the open / close valve 82 provided in the IPA supply line 23 and opening the hot N ₂ supply line 24 open / close valve 83.

  Each of the first gas supply nozzle 71 and the second gas supply nozzle 72 has a cylindrical shape, and a gas injection port for ejecting a drying processing gas or the like is in the longitudinal direction (direction perpendicular to the paper surface in FIG. 2). Have a structure formed at regular intervals. The exhaust nozzle 73 has a cylindrical shape, and a slit-type intake port having a fixed length for taking in the gas in the chamber 5 is fixed in the longitudinal direction (direction perpendicular to the paper surface in FIG. 2). It has a structure formed at intervals.

As shown in FIG. 2, the first gas supply nozzle 71 injects the processing gas for drying and hot N ₂ injected from the gas injection port obliquely upward without directly hitting the wafer W accommodated in the chamber 5. Is arranged to be. The drying processing gas and hot N ₂ sprayed from the first gas supply nozzle 71 pass through the upper left and upper right of the wafer W, rise toward the upper part of the inner peripheral surface of the lid 62, and merge at the upper center of the lid 62. Then, it descends, flows between the wafers W, and flows down along the surface of the wafers W.

The second gas supply nozzle 72 is also arranged such that the normal temperature N ₂ injected from the gas injection port is injected obliquely upward without directly hitting the wafer W accommodated in the chamber 5. The normal temperature N ₂ sprayed from the second gas supply nozzle 72 passes through the upper left and upper right of the wafer W, rises toward the upper part of the inner peripheral surface of the lid 62, joins and falls at the upper center of the lid 62, It flows between the wafers W and flows down along the surface of the wafers W.

  Next, the configuration of the shutter 10 will be described. As described above, the seal ring 135 is provided on the periphery of the upper surface of the shutter 10. As shown in FIG. 2, the inside of the seal ring 135 has a substantially conical shape, and has a slope (concave surface) that is gently depressed toward the center. The shutter 10 is formed with a drain port 91 that opens at the deepest part of the concave surface, and an aspirator 92 as a suction mechanism is connected to the drain port 91.

  FIG. 3 shows an enlarged cross-sectional view of the central portion of the shutter 10. A substantially conical suction control member 93 is disposed on the opening of the drain port 91. The suction control member 93 is fixed to a screw 94 disposed on the rear surface of the shutter 10 so as to protrude toward the upper surface of the shutter 10. In such a configuration, when the aspirator 92 is operated, it flows into a gap (opening) formed between the outer periphery of the suction control member 93 and the upper surface of the shutter 10 along the upper surface of the shutter 10, and further, the liquid discharge port 91. A fluid flow can be generated that flows into the fluid.

  For example, when the wafer W that has been rinsed by DIW in the liquid processing unit is pulled up to the drying processing unit 3, and then the shutter 10 partitions the liquid processing unit 2 and the drying processing unit 3, water droplets are generated from the wafer W. It falls on the shutter 10 and DIW accumulates on the shutter 10. Further, when the wafer W is dried by the drying process gas thereafter, a droplet in which DIW and IPA are mixed falls from the wafer W. Since the liquid droplets dropped on the upper surface of the shutter 10 in this manner are efficiently collected using the fluid flow by the suction control member 93, the liquid remaining on the upper surface of the shutter 10 can be reduced. Further, since the suction control member 93 is a substantially conical concave surface, the liquid droplet that has dropped from the wafer W onto the upper surface of the suction control member 93 flows down the slope by gravity and is guided to the liquid discharge port 91. In order to make it easier for the droplets to move on the upper surface of the shutter 10, a shutter 10 made of a metal plate such as stainless steel coated with a fluororesin or a hydrophobic resin is preferably used.

Thus, by dropping the liquid that has fallen onto the shutter 10 and removing the accumulated liquid, it is possible to prevent liquid droplets from dropping from the shutter 10 to the liquid processing unit 2 and contaminating the liquid processing unit 2 when the shutter 10 is moved horizontally. The Further, mist or the like from droplets of the shutter 10 due to hot N ₂ or normal temperature N ₂ air current supplied to the chamber 5 is suppressed from contaminating the wafer W or the inner surface of the chamber 5. Further, by using the aspirator 92 as a suction mechanism, pulsation is not generated and constant suction is possible.

  The height of the suction control member 93 is limited to a height that does not contact the shutter box 11 when the shutter 10 is moved in the horizontal direction. For this reason, when the outer diameter of the suction control member 93 becomes longer, the inclination of the upper surface becomes gentle and DIW or the like tends to accumulate on the upper surface of the suction control member 93. On the other hand, when the outer diameter of the suction control member 93 becomes shorter, the shutter 10 It is difficult to cause a fluid flow along the upper surface of the substrate. From such a viewpoint, the outer diameter of the suction control member 93 is preferably set to 30 to 40 mm, for example. If the gap h (that is, the height h of the opening) formed between the outer peripheral end of the suction control member 93 and the upper surface of the shutter 10 is lower than the height of the droplet, the droplet can be efficiently sucked. Therefore, for example, it is preferably 0.5 mm or more and 1.0 mm or less, and more preferably 0.6 mm or more and 0.8 mm or less. If the gap h is narrow, the pressure loss increases. Conversely, if the gap h is wide, the liquid suction efficiency deteriorates, and the fluid flow along the upper surface of the shutter 10 is difficult to occur. The opening diameter of the drain port 91 is set shorter than the outer diameter of the suction control member 93.

  When the suction control member 93 is disposed and not disposed, water droplets are dropped in the vicinity of the center of the shutter 10 so that the total amount becomes 50 g, and a suction operation for removing water droplets for 60 seconds is performed. When 93 was not disposed, a liquid residue of about 5 g was observed on the shutter, but when the suction control member 93 was disposed, the liquid residue was reduced to 1 g or less. Similarly, when water droplets are dropped on the outer peripheral portion of the shutter 10 to a total amount of 50 g and a suction operation for removing water droplets for 60 seconds is performed, when the suction control member 93 is not disposed, about Although a liquid residue of about 10 g was recognized, the liquid residue when the suction control member 93 was arranged was reduced to about 5 g. It can be easily understood that such an effect can be obtained in the same manner in a process in which the wafer W is rinsed in the liquid processing unit 2 and then dried.

Various driving devices provided in the cleaning processing apparatus 1 configured as described above, for example, open / close valves 51a and 52a for supplying DHF and DIW to the liquid processing unit 2, and DHF and the like are discharged from the inner tank 30 An opening / closing valve 37 for opening, opening / closing valves 83, 82, and 86 for supplying hot N ₂ , IPA, and normal temperature N ₂ to the drying processing unit 3, a lid raising / lowering mechanism 64 for the lid 62 constituting the chamber 5, and the shutter 10. Drive control of the aspirator 92 connected to the formed drainage port 91, the guide raising / lowering mechanism 28 for raising and lowering the wafer guide 4 and the like is performed by the control device 99.

Next, a specific embodiment of the substrate cleaning method using the cleaning processing apparatus 1 will be described. FIG. 4 is a flowchart showing the processing steps of the wafer W. First, in the drying processing unit 3, the upper surface of the main body 61 is closed by the lid 62, and the lower surface of the main body 61 is closed by the shutter 10, so that the chamber 5 is sealed (STEP 1a). In addition, hot N ₂ is supplied at a constant flow rate through the first gas supply nozzle 71 into the chamber 5 thus sealed, and at that time, natural exhaust is performed through the exhaust nozzle 73 and the natural exhaust line 49 (STEP 1b). . Further, a predetermined concentration of DHF is stored in the inner tank 30 of the liquid processing tank 6 (STEP 1c). In this state, the portion of the wafer guide 4 that holds the wafer W is disposed in the drying processing unit 3.

Next, the lid 62 is raised and held at a position P1 (see FIG. 2), and the holding portion 26 of the wafer guide 4 is positioned above the main body portion 61 of the chamber 5, and then hot N ₂ into the chamber 5 is reached. Is stopped (STEP 2). Then, 50 wafers W are delivered from the external substrate transfer device (not shown) to the holding unit 26 of the wafer guide 4 (STEP 3). Next, the wafer guide 4 is lowered to accommodate the wafer W in the main body 61 of the chamber 5, the lid 62 is lowered and held at the position P <b> 2 (see FIG. 2), and the exhaust nozzle 73 and the forced exhaust line 48. After the forced exhaust of the atmosphere in the chamber 5 is started, the shutter 10 is moved into the shutter box 11 to open the space between the liquid processing unit 2 and the drying processing unit 3 (STEP 4).

  In STEP 4, the down flow from the fan filter unit (FFU) 12 flows into the chamber 5, and a clean air flow from the upper surface opening 61 a of the main body 61 toward the exhaust nozzle 73 is formed. Thereby, even if the shutter 10 is opened, it is possible to prevent the DHF atmosphere stored in the liquid processing tank 6 from rising to the drying processing unit 3. This prevents the inner surface of the chamber 5 from being contaminated by the DHF atmosphere (steam) or leaking outside through the upper surface opening 61a of the main body 61. In addition, since clean air supplied from the fan filter unit (FFU) 12 is used to form an air flow in the drying processing unit 3, contamination of the chamber 5 can be economically prevented.

  Next, the wafer guide 4 is further lowered, the held wafer W is immersed in DHF stored in the inner tank 30, and silicon oxide removal processing is performed (STEP 5). Even during the processing of STEP5, the lid 62 is held at the position P2, and the atmosphere in the chamber 5 is forcibly exhausted through the exhaust nozzle 73 and the forced exhaust line 48, thereby preventing the chamber 5 from being contaminated by the DHF atmosphere.

  When the processing of the wafer W by DHF is completed, DIW is supplied into the inner tank 30 from the processing liquid supply nozzle 35 while the wafer W is placed in the inner tank 30, and the DHF in the inner tank 30 is replaced with DIW. Then, the wafer W is rinsed (STEP 6). At this time, DHF or DIW overflowed from the inner tank 30 is received by the intermediate tank 31 and drained through the drain pipe 41 and the trap 42.

  Note that while replacing the DHF in the inner tank 30 with DIW, the lid 62 is disposed at the position P2 and forced exhaust is performed through the exhaust nozzle 73 in the same manner as during the DHF processing of the wafer W. The step of replacing DHF in the inner tank 30 with DIW may be performed, for example, by discharging DHF to the box 13 through the drain pipe 36 and then supplying DIW to the inner tank 30.

Whether or not DHF in the inner tank 30 has been replaced with DIW can be determined from the measured value of the concentration sensor 53. Accordingly, when it is determined that the DHF in the inner tank 30 is replaced with DIW by the measured value of the concentration sensor 53 and DHF is discharged from the inner tank 30, the forced exhaust line 48 is switched to the natural exhaust line 49, and the lid 62 is positioned. It is lowered to P3 (see FIG. 2) to close the upper surface opening 61a of the main body 61, and hot N ₂ from the first gas supply nozzle 71 and room temperature N ₂ from the second gas supply nozzle 72 into the chamber 5, respectively. Inject (STEP 7). Thus, the inside of the chamber 5 is maintained in the N ₂ atmosphere.

In this STEP 7, since the hot N ₂ passes through the processing gas supply line 21, the processing gas supply line 21 is heated. Thereby, the temperature fall of the drying process gas at the time of supplying the drying process gas containing IPA vapor | steam in the chamber 5 later can be suppressed. In addition, by heating the chamber 5, it is possible to prevent the IPA from condensing on the inner wall of the chamber 5 when the drying process gas is supplied into the chamber 5 later. Thereby, the usage-amount of IPA can be reduced. In STEP 6 and STEP 7, it is preferable to exhaust the DHF atmosphere that may remain in the shutter box 11 by further exhausting the shutter box 11.

When rinsing processing of the wafer W by DIW is completed, the wafer guide 4 is raised so that the wafer W is accommodated in the chamber 5, and then the liquid processing unit 2 and the drying processing unit 3 are isolated by the shutter 10. (STEP8). In STEP 8, while the wafer W is being raised, the supply of the normal temperature N ₂ from the second gas supply nozzle 72 into the chamber 5 is stopped, and the supply of hot N ₂ from the first gas supply nozzle 71 is Continue to warm process gas supply line 21. At the end of STEP 8, DIW droplets adhering to the wafer W fall on the shutter 10.

  After the liquid processing unit 2 and the drying processing unit 3 are separated from each other by the shutter 10, the DIW in the inner tank 30 provided in the liquid processing unit 2 is drained by opening the opening / closing valve 37. It is preferable to discharge to the box 13 through 36 and then fill the inner tank 30 with a constant concentration of DHF to prepare for the next treatment. The DIW discharged to the box 13 is discharged to the outside from the drainage pipe 141.

Subsequently, the wafer W is dried (STEP 9). FIG. 5 is a flowchart showing the details of each step of STEP9. When the wafer W is accommodated in the sealed chamber 5 and the shutter 10 is closed by the STEP 8, the drying process gas (that is, hot N ₂ containing a predetermined amount of IPA vapor) is supplied from the first gas supply nozzle 71. Is started (STEP 9a).

  The drying process gas is injected into the chamber 5 from the first gas supply nozzle 71 and rises toward the upper part of the inner peripheral surface of the lid 62, and then flows between the wafers W from above the wafers W. It flows down along the surface of the gas and is discharged to the outside through the exhaust nozzle 73. At this time, IPA is mixed with moisture adhering to the wafer W and falls onto the shutter 10. For example, after 20 to 30 seconds have elapsed since the supply of the drying process gas, suction and drainage by the aspirator 92 connected to the drainage port 91 formed in the shutter 10 is started (STEP 9b). .

  After the shutter 10 is closed, the operation of the aspirator 92 is started with a certain interval in this way, and when the liquid accumulated on the shutter 10 is removed by suction, the shutter 10 is closed and the aspirator is simultaneously closed. As compared with the case of starting the operation 92, the liquid remaining on the shutter 10 can be reduced. This gives a time for the droplets that have fallen on the shutter 10 to combine, and when the liquid in the portion close to the gap formed between the suction control member 93 and the upper surface of the shutter 10 is sucked, This is considered to be due to the fact that the distant liquid part that is coupled is easily sucked, and the liquid becomes easy to flow through the concave surface formed in the shutter 10 due to the large droplets.

When a certain time (for example, 90 seconds) elapses, the IPA supply from the IPA supply line 23 is stopped so that only hot N ₂ is supplied from the first gas supply nozzle 71 into the chamber 5 (STEP 9c). . Further, after a predetermined time (for example, 30 to 60 seconds) has elapsed since the supply of IPA was stopped, the aspirator 92 is stopped and the droplet suction of the shutter 10 is ended (STEP 9d). Further, after a predetermined time has passed, the supply of hot N _{2 into} the chamber 5 is continued and the supply of the room temperature N _{2 into} the chamber 5 from the second gas supply nozzle 72 is started (STEP 9e). At this time, the drying process of the wafer W is completed. By supplying room temperature N ₂ into the chamber 5, the wafer W is cooled.

After a predetermined time has elapsed from the start of the supply of the normal temperature N ₂ , the lid 62 is raised to the position P 1, and the wafer guide 4 is raised substantially simultaneously with this to bring the wafer W to the upper side of the main body 61 of the chamber 5. (STEP 10). At this time, supply of nitrogen gas from the first gas supply nozzle 71 and the second gas supply nozzle 72 is stopped, and clean air from the fan filter unit (FFU) 12 is drawn into the chamber 5 through the forced exhaust line 48. Next, a substrate transfer device (not shown) accesses the wafer guide 4 from the outside, and unloads the wafer W from the cleaning processing apparatus 1 (STEP 11).

  As mentioned above, although embodiment of this invention was described, this invention is not limited to such a form. For example, although the shutter 10 has a concave top surface, a conventional case where the suction control member 93 is not disposed by disposing the suction control member 93 even when the top surface of the shutter 10 is a horizontal surface. As a result, the liquid remaining on the shutter 10 can be reduced.

  In the above description, DHF is taken up as a chemical solution, but is not limited thereto, and other chemical solutions such as SC-1 cleaning solution may be used. The present invention is not limited to the cleaning process and can be applied to, for example, a wet etching process. Furthermore, the substrate is not limited to a semiconductor wafer, and may be a glass substrate for liquid crystal display, a printed wiring board, a ceramic substrate, or the like.

  The present invention is suitable for an apparatus for performing various liquid treatments such as a cleaning processing apparatus and an etching processing apparatus for various substrates such as semiconductor wafers.

Sectional drawing which shows schematic structure of a washing | cleaning processing apparatus. Sectional drawing which shows the more detailed structure of a drying process part and a shutter. The cross-sectional enlarged view of the center part of a shutter. The flowchart which shows the process process of a wafer. The flowchart which shows a drying process process in detail.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Cleaning processing apparatus 2; Liquid processing part 3; Drying process part 4; Wafer guide 5; Chamber 6; Liquid processing tank 10; Shutter 71; First gas supply nozzle 72; Second gas supply nozzle 73; Drainage port 92; Aspirator 93; Suction control member

Claims (11)

A liquid processing section for processing the substrate with the processing liquid;
A drying processing unit provided on the liquid processing unit and drying the substrate;
A substrate transfer device for transferring a substrate between the liquid processing unit and the drying processing unit;
A shutter that is movable in a horizontal direction so as to be able to open and close between the liquid processing unit and the drying processing unit, and has a drain port formed therein;
A suction mechanism connected to the drainage port;
A suction control member that is provided on the opening of the drainage port and generates a fluid flow that flows along the upper surface of the shutter and flows into the drainage port when the suction mechanism is operated;
A substrate processing apparatus comprising:   The substrate processing apparatus according to claim 1, wherein the drain port is formed substantially at the center of the shutter.   The substrate processing apparatus according to claim 1, wherein the suction control member has a substantially conical shape.   4. The substrate processing apparatus according to claim 3, wherein a gap formed between an outer peripheral end of the substantially conical suction control member and an upper surface of the shutter is 0.5 mm or more and 1.0 mm or less.   The substrate processing apparatus according to claim 3, wherein an opening diameter of the drain port is shorter than an outer diameter of the substantially conical suction control member.   6. The substrate processing according to claim 1, wherein an upper surface of the shutter is a substantially conical concave surface, and the drainage port is provided at a deepest portion of the concave surface. apparatus.   The substrate processing apparatus according to claim 1, wherein the suction mechanism is an aspirator. A processing gas supply mechanism for supplying a processing gas to the drying processing unit;
The supply of the processing gas to the drying processing unit is started, the drainage from the drainage port is started after a predetermined time has elapsed, and then the supply of the processing gas is stopped after the predetermined time has passed, and then the drainage port A control device for controlling the processing gas supply mechanism and the suction mechanism so as to stop drainage from
The substrate processing apparatus according to claim 1, further comprising: An inert gas supply mechanism for supplying an inert gas to the drying processing unit;
The control device starts supplying inert gas to the drying processing unit substantially simultaneously with the start of supply of processing gas to the drying processing unit, and stops the drainage from the drainage port, and then deactivates the inert gas. Controlling the inert gas supply mechanism so as to stop the supply of gas to the drying processing unit;
The chemical treatment and water washing treatment of the substrate is performed in the liquid treatment section, and the drying treatment of the substrate after the water washing treatment is performed using isopropyl alcohol vapor as the processing gas in the drying treatment section. 9. The substrate processing apparatus according to 8. A step of liquid-treating the substrate in a liquid treatment section for treating the substrate with a predetermined treatment liquid;
A step of pulling up the substrate after the liquid processing to a drying processing unit provided above the liquid processing unit;
Isolating the liquid processing unit and the drying processing unit with a shutter;
Drying the substrate in the drying processing unit,
The substrate drying process includes:
Starting the supply of processing gas to the drying processing unit;
After a lapse of a certain time from the start of the supply of the processing gas, the drainage liquid flows along the upper surface of the shutter using a suction control member provided on an opening of a drainage port provided in the shutter. Generating a fluid flow flowing into the mouth, and starting suction and drainage of the liquid dropped on the shutter through the drainage port;
A step of stopping the supply of the processing gas after elapse of a predetermined time after starting drainage from the drainage port;
A step of stopping suction and drainage from the drainage port after a lapse of a predetermined time after stopping the supply of the processing gas;
A substrate processing method comprising: The liquid treatment of the substrate includes a water washing treatment with pure water,
In the drying step, isopropyl alcohol vapor is used as the processing gas, and the supply of the inert gas to the drying processing unit is further started substantially simultaneously with the start of the supply of isopropyl alcohol vapor to the drying processing unit, The substrate processing method according to claim 10, wherein the supply of the inert gas to the drying processing unit is stopped after the suction and drainage from the drainage port is stopped.

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