JP3742986B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate processing apparatus that performs predetermined processing by irradiating a substrate to be processed with ultraviolet rays.
[0002]
[Prior art]
In the manufacture of semiconductor devices, various fine processing is performed on the premise that the surface of a substrate to be processed (for example, a semiconductor wafer, an LCD substrate, etc.) is in a cleaned state. Therefore, the surface of the substrate to be processed is cleaned prior to each processing or between the processings. For example, in the photolithography process, the surface of the substrate to be processed is cleaned prior to resist application.
[0003]
Conventionally, a dry cleaning technique using ultraviolet irradiation is known as a cleaning method for removing organic substances on the surface of a substrate to be processed. This ultraviolet irradiation cleaning technique excites oxygen using ultraviolet rays of a predetermined wavelength (185 nm, 254 nm when a low-pressure mercury lamp is used as an ultraviolet light source, and 172 nm when a dielectric barrier discharge lamp is used), and generates ozone and generation period. The organic matter on the substrate surface is oxidized and vaporized and removed by oxygen.
[0004]
A conventional typical ultraviolet irradiation type cleaning apparatus accommodates a plurality of lamps serving as an ultraviolet light source as described above in a lamp chamber having a quartz glass window, and cleans adjacent to the lamp chamber through the quartz glass window. A substrate to be processed is disposed in the processing chamber, and ultraviolet rays emitted from a lamp in the lamp chamber are irradiated to the surface of the substrate to be processed for a certain period of time through the quartz glass window. Recently, a device has been made compact (reduced number of lamps, miniaturized quartz glass window, etc.) by a mechanism for relatively moving or scanning the lamp in parallel with the surface of the substrate to be processed.
[0005]
[Problems to be solved by the invention]
In the ultraviolet irradiation type cleaning apparatus as described above, in order to obtain the desired cleaning effect, it is necessary to secure the illuminance and light quantity of ultraviolet rays irradiated to the substrate to be processed from the ultraviolet lamp, respectively, above a predetermined value. The specifications of each part of the device are made so as to satisfy the ultraviolet irradiation conditions. However, when the luminance of the ultraviolet lamp decreases with time, the illuminance or light intensity of the ultraviolet rays with respect to the substrate to be processed may be insufficient, leading to poor cleaning. However, this type of conventional device does not have a means for accurately measuring the UV illuminance on the substrate to be processed or a means for accurately compensating for changes in the UV illuminance, thus stabilizing the quality and efficiency of the UV cleaning process. It was difficult to maintain.
[0006]
Further, in an apparatus using a dielectric barrier discharge lamp, ultraviolet excimer light having a wavelength of 172 nm emitted from the lamp is very easily absorbed by oxygen, and it takes from the quartz glass window to the surface of the substrate to be processed. The greater the distance, the more exponentially decays. For this reason, it is preferable to make the gap between the two (the quartz glass window and the substrate to be processed) as narrow as possible, and is usually set to 3 to 7 mm in consideration of dimensional errors and mechanical accuracy errors. However, even in such a small gap, the illuminance of ultraviolet rays is attenuated significantly to about a few, and the energy efficiency is low.
[0007]
Furthermore, in this type of apparatus, there is a problem that a reaction product due to ultraviolet rays adheres to the outer surface (surface on the substrate side) of quartz glass. That is, organic substances or chemicals adhering to or drifting on the surface of the substrate to be processed react with ultraviolet light energy, and the reaction product adheres to the quartz glass facing the substrate close to the white color. As a result, the ultraviolet transmission property of the quartz glass is deteriorated, and the reaction product or the precipitate may be peeled off from the quartz glass to cause particles.
[0008]
The present invention has been made in view of such conventional problems, and the substrate processing in which the illuminance of ultraviolet rays to the substrate to be processed is appropriately managed in the ultraviolet irradiation processing to stably maintain the processing quality and efficiency. It is a first object to provide an apparatus.
[0009]
A second object of the present invention is to provide a substrate processing apparatus that effectively protects a window member for ultraviolet irradiation from an ultraviolet reaction product.
[0010]
[Means for Solving the Problems]
  In order to achieve the above object, a substrate processing apparatus of the present invention includes a mounting table for mounting and supporting the substrate in a substrate processing apparatus for performing predetermined processing by irradiating a substrate to be processed with ultraviolet rays, and power. Emits UV lightpluralA lamp and a window member that transmits ultraviolet light, and the window member transmits ultraviolet light emitted from the lamp.throughUV irradiation means for irradiating the substrate on the mounting table,An optical sensor provided on the mounting table at a position that does not interfere with the substrate, and irradiating the substrate on the mounting table from the ultraviolet irradiation means.Ultraviolet illuminance measuring means for measuring the illuminance of ultraviolet rays;Before starting the ultraviolet irradiation process on the substrate,Irradiation distance adjustment means for variably adjusting the distance between the ultraviolet irradiation means and the mounting table according to the ultraviolet illuminance measurement value obtained from the ultraviolet illuminance measurement means,During the ultraviolet irradiation treatment,Ultraviolet rays from the ultraviolet irradiation means scan the surface to be processed of the substrate on the mounting table.At the same time, the light sensor passes under the window member,Drive means for moving either one or both of the mounting table and the ultraviolet irradiation means in a predetermined direction;During the ultraviolet irradiation process, the ultraviolet illuminance distribution under the window member is measured or monitored based on the ultraviolet illuminance measurement value obtained from the ultraviolet illuminance measuring means, and a lamp having an abnormally low brightness or a lamp that cannot be lit is detected. UV illuminance monitoring means toHave
[0011]
  The above substrate processing apparatusIn, the illuminance of ultraviolet rays given to the substrate to be processed on the mounting table by the ultraviolet irradiation means isEven if it changes over time, the ultraviolet illuminance is measured by the ultraviolet illuminance measuring means prior to the ultraviolet irradiation treatment, and according to the measured value of the ultraviolet illuminance.Since the irradiation distance is variably adjusted so as to compensate for the illuminance change by the irradiation distance adjusting means, the ultraviolet illuminance can be kept constant or stable.Furthermore, during the ultraviolet irradiation process, when the mounting table moves relative to the ultraviolet irradiation means so that the ultraviolet rays from the ultraviolet irradiation means scan the surface of the substrate on the mounting table, The light sensor of the ultraviolet illuminance measurement means provided passes under the window member, and the ultraviolet illuminance monitor means measures the ultraviolet illuminance distribution under the window member based on the ultraviolet illuminance measurement value obtained from the ultraviolet illuminance measurement means. Monitor and detect any lamps in use that are abnormally low in brightness or cannot be lit. In this way, both temporal and spatial changes in UV illuminance can be accurately monitored or managed with a simple configuration using a common optical sensor, thereby maintaining stable processing quality and efficiency. can do.
[0012]
  According to a preferred aspect of the present invention, the optical sensor of the ultraviolet illuminance measuring means is arranged at a position in front of the substrate in the scanning direction. The plurality of lamps are cylindrical dielectric barrier discharge lamps, and are arranged side by side in a horizontal direction perpendicular to the longitudinal direction of the lamp.
[0013]
  AnotherPreferred embodimentThe irradiation distance adjusting means includes means for variably adjusting the distance between the ultraviolet irradiation means and the mounting table according to the thickness of the substrate to be processed placed on the mounting table. It may be. As described above, using the thickness of the substrate to be processed as an illuminance adjustment parameter is also effective in improving the accuracy of illuminance measurement or illuminance adjustment.
[0014]
Further, in order to stably maintain the ultraviolet illuminance on the substrate at a desired value, preferably, the irradiation distance adjusting unit includes a reference illuminance setting unit that sets a desired reference illuminance, and the ultraviolet illuminance measurement value is converted to the reference illuminance. And a relative position adjusting means for adjusting the relative position between the mounting table and the ultraviolet irradiation means so that the comparison error approaches zero.
[0015]
Further, in order to perform stable and good ultraviolet irradiation treatment, preferably, the irradiation distance adjusting unit is a maximum interval setting unit that sets a maximum value for the interval between the window member and the mounting table or the substrate, and When the interval is likely to exceed the maximum value in the variable adjustment of the interval, it may have maximum interval limiting means for limiting the interval to the maximum value, and / or the window member and the mounting table or the substrate. Minimum interval setting means for setting a minimum value with respect to the interval, and minimum interval limiting means for limiting the interval to the minimum value when the interval is likely to divide the minimum value in the variable adjustment of the interval. It's okay.
[0016]
  According to a preferred aspect of the present invention, there is provided an inert gas flow forming means for forming an inert gas flow in a gap between the window member and the substrate on the mounting table. The inert gas flow forming means preferably injects the inert gas from the vicinity of the window member toward the gap between the window member and the substrate on the mounting table so as to face the mounting table. You may comprise an inert gas injection means and the inert gas suction means which sucks the inert gas which passed through the said gap in the position on the opposite side to the said inert gas injection means on both sides of the said window member. In this case, it is preferable that the inert gas injection means and the inert gas suction means are respectively disposed on the front side and the rear side of the window member in the movement direction as viewed from the mounting table side.
[0017]
  In the above configuration, an inert gas flow is formed in the gap between the window member and the substrate on the mounting table.Air, especially oxygen, is expelled from the gapAndThe degree to which the ultraviolet rays emitted from the window member of the ultraviolet irradiation means into the processing chamber are absorbed and attenuated by oxygen before reaching the substrate is reduced. This requires less lamp power consumption to obtain the desired illuminance and extends the lamp life. In addition, since the ultraviolet reaction product is also removed from the gap along the flow of the inert gas, it is difficult to adhere to the window member.
[0018]
  According to a preferred aspect of the present invention,The drive means includes a rotation drive means for rotating and moving the other one at the second position while fixing either the mounting table or the ultraviolet irradiation means at the first position.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
[0020]
FIG. 1 shows a coating and developing processing system as an example of a system in which the substrate processing apparatus of the present invention can be incorporated. This coating / development processing system is installed in a clean room and uses, for example, an LCD substrate as a substrate to be processed, and performs cleaning, resist coating, pre-baking, development, and post-baking in the photolithography process in the LCD manufacturing process. is there. The exposure process is performed by an external exposure apparatus (not shown) installed adjacent to this system.
[0021]
This coating and developing system is roughly divided into a cassette station (C / S) 10, a process station (P / S) 12, and an interface unit (I / F) 14.
[0022]
A cassette station (C / S) 10 installed at one end of the system has a cassette stage 16 on which a predetermined number, for example, four cassettes C for storing a plurality of substrates G can be placed, and a cassette C on the stage 16. And a transport mechanism 20 for taking in and out the substrate G. The transport mechanism 20 has a means for holding the substrate G, for example, a transport arm, can be operated with four axes of X, Y, Z, and θ, and is a main transport device on the process station (P / S) 12 side to be described later. 38 and the substrate G can be transferred.
[0023]
The process station (P / S) 12 includes, in order from the cassette station (C / S) 10 side, a cleaning process unit 22, a coating process unit 24, and a development process unit 26, a substrate relay unit 23, a chemical solution supply unit 25, and It is provided in a horizontal row via (spaced) the space 27.
[0024]
The cleaning process unit 22 includes two scrubber cleaning units (SCR) 28, an upper and lower ultraviolet irradiation / cooling unit (UV / COL) 30, a heating unit (HP) 32, and a cooling unit (COL) 34. Contains.
[0025]
The coating process unit 24 includes a resist coating unit (CT) 40, a vacuum drying unit (VD) 42, an edge remover unit (ER) 44, an upper and lower two-stage adhesion / cooling unit (AD / COL) 46, An upper and lower two-stage heating / cooling unit (HP / COL) 48 and a heating unit (HP) 50 are included.
[0026]
The development process unit 26 includes three development units (DEV) 52, two upper and lower two-stage heating / cooling units (HP / COL) 55, and a heating unit (HP) 53.
[0027]
Conveying paths 36, 52, and 58 are provided in the longitudinal direction at the center of each of the process units 22, 24, and 26, and the main conveying devices 38, 54, and 60 move along the respective conveying paths, and each of the process units 22 The unit is accessed to carry in / out or carry the substrate G. In this system, in each process unit 22, 24, 26, a spinner system unit (SCR, CT, DEV, etc.) is arranged on one side of the transport paths 36, 52, 58, and heat treatment or Irradiation processing units (HP, COL, UV, etc.) are arranged.
[0028]
The interface unit (I / F) 14 installed at the other end of the system is provided with an extension (substrate transfer unit) 57 and a buffer stage 56 on the side adjacent to the process station 12, and is transported to the side adjacent to the exposure apparatus. A mechanism 59 is provided.
[0029]
FIG. 2 shows a processing procedure in this coating and developing processing system. First, in the cassette station (C / S) 10, the transport mechanism 20 takes out one substrate G from a predetermined cassette C on the stage 16, and the main of the cleaning process unit 22 of the process station (P / S) 12. It is transferred to the conveying device 38 (step S1).
[0030]
In the cleaning process section 22, the substrate G is first sequentially carried into an ultraviolet irradiation / cooling unit (UV / COL) 30, subjected to dry cleaning by ultraviolet irradiation in the upper ultraviolet irradiation unit (UV), and then cooled in the lower stage. The unit (COL) is cooled to a predetermined temperature (step S2). This ultraviolet irradiation cleaning removes organic substances on the substrate surface. Thereby, the wettability of the substrate G is improved, and the cleaning effect in the scrubbing cleaning in the next step can be enhanced.
[0031]
Next, the substrate G is subjected to a scrubbing cleaning process by one of the scrubber cleaning units (SCR) 28 to remove particulate dirt from the substrate surface (step S3). After the scrubbing cleaning, the substrate G is subjected to dehydration treatment by heating in the heating unit (HP) 32 (step S4), and then cooled to a constant substrate temperature by the cooling unit (COL) 34 (step S5). Thus, the pretreatment in the cleaning process unit 22 is completed, and the substrate G is transferred to the coating process unit 24 by the main transfer device 38 via the substrate transfer unit 23.
[0032]
In the coating process unit 24, the substrate G is first sequentially carried into an adhesion / cooling unit (AD / COL) 46, and undergoes a hydrophobic treatment (HMDS) in the first adhesion unit (AD) (step S6). The cooling unit (COL) cools to a constant substrate temperature (step S7).
[0033]
Thereafter, the substrate G is coated with a resist solution by a resist coating unit (CT) 40, and then subjected to a drying process by a reduced pressure drying unit (VD) 42, and then an edge remover unit (ER) 44 of the periphery of the substrate. Excess (unnecessary) resist is removed (step S8).
[0034]
Next, the substrate G is sequentially carried into the heating / cooling unit (HP / COL) 48, and the first heating unit (HP) performs baking after coating (pre-baking) (step S9), and then the cooling unit ( COL) to cool to a constant substrate temperature (step S10). In addition, the heating unit (HP) 50 can also be used for baking after this application | coating.
[0035]
After the coating process, the substrate G is transported to the interface unit (I / F) 14 by the main transport device 54 of the coating process unit 24 and the main transport device 60 of the development process unit 26, and is passed from there to the exposure apparatus. (Step S11). In the exposure apparatus, a predetermined circuit pattern is exposed on the resist on the substrate G. After the pattern exposure, the substrate G is returned from the exposure apparatus to the interface unit (I / F) 14. The transport mechanism 59 of the interface unit (I / F) 14 passes the substrate G received from the exposure apparatus to the development process unit 26 of the process station (P / S) 12 via the extension 57 (step S11).
[0036]
In the development process section 26, the substrate G is subjected to development processing in any one of the development units (DEV) 52 (step S12), and then sequentially carried into one of the heating / cooling units (HP / COL) 55, Post baking is performed in the first heating unit (HP) (step S13), and then the substrate is cooled to a constant substrate temperature in the cooling unit (COL) (step S14). A heating unit (HP) 53 can also be used for this post-baking.
[0037]
The substrate G that has undergone a series of processing in the development process section 26 is returned to the cassette station (C / S) 10 by the transfer devices 60, 54, and 38 in the process station (P / S) 24, where the transfer mechanism 20 Is stored in one of the cassettes C (step S1).
[0038]
In the coating and developing system, the present invention can be applied to the ultraviolet irradiation unit (UV) of the cleaning process unit 22. Hereinafter, an embodiment in which the present invention is applied to an ultraviolet irradiation unit (UV) will be described with reference to FIGS.
[0039]
As shown in FIG. 3, an ultraviolet irradiation unit (UV) according to an embodiment of the present invention has an ultraviolet irradiation window 62 made of synthetic quartz glass attached to the lower surface, and a plurality of (in the illustrated example, three) indoors. A cylindrical ultraviolet lamp 64 (1), 64 (2)..., 64 (n) is arranged in a horizontal direction perpendicular to the longitudinal direction of the lamp, and is adjacent to the lamp chamber 66. And a cleaning processing chamber 68 provided.
[0040]
In the lamp chamber 66, each of the ultraviolet lamps 64 (1) to 64 (n) may be, for example, a dielectric barrier discharge lamp, and emits light upon receiving commercial AC power from a lamp power supply unit (120) described later, thereby causing organic contamination. UV light (ultraviolet excimer light) having a wavelength of 172 nm suitable for cleaning of the substrate is emitted. A concave reflecting mirror 70 having an arc-shaped cross section is disposed behind or above each of the ultraviolet lamps 64 (1) to 64 (n), and above or to the side of each of the lamps 64 (1) to 64 (n). The emitted ultraviolet light is reflected by the concave part of the reflecting mirror immediately above and directed toward the ultraviolet irradiation window 62 side.
[0041]
In the lamp chamber 66, a cooling jacket (not shown) for cooling the ultraviolet lamps 64 (1) to 64 (n) by, for example, a water cooling method, or an oxygen chamber that absorbs ultraviolet rays (deteriorates lamp luminous efficiency). A gas distribution mechanism (not shown) for introducing and filling an inert gas, for example, N2 gas, for preventing the entry of gas may be provided.
[0042]
On both sides of the lamp chamber 66, an inert gas injection section 72 and an inert gas suction section for flowing an inert gas such as N2 gas for removing oxygen or air along the lower surface of the ultraviolet irradiation window 62 during the ultraviolet cleaning process. 74 is provided.
[0043]
The inert gas injection unit 72 is arranged on the right side of the lamp chamber 66 in FIG. 3, that is, on the front side in the table moving direction (Y direction) during scanning, which will be described later, and the ultraviolet lamps 64 (1) to 64 (n). A gas pipe 76 extending in parallel with the gas pipe 76, a number of inert gas injection ports 78 provided in a row at regular intervals in the gas pipe 76, and a predetermined flow rate and pressure of inert gas in the gas pipe 76. And the gas guide member 82 for guiding the inert gas injected from each inert gas injection port 78 to the lower side of the ultraviolet irradiation window 62.
[0044]
The inert gas suction portion 74 is arranged on the left side of the lamp chamber 66 in FIG. 3, that is, on the rear side in the table moving direction (Y direction) during scanning, and is parallel to the ultraviolet lamps 64 (1) to 64 (n). A gas pipe 84 extending to the gas pipe, a number of gas inlets 86 provided in a line at regular intervals to the gas pipe 84, and a gas that applies a negative pressure to the gas pipe 84 and exhausts the inflowed gas. The exhaust part 88 and the gas guide member 90 for guiding the inert gas flowing under the ultraviolet irradiation window 62 from the inert gas injection part 72 toward the gas inlet 86 are provided. Note that the arrangement positions of the inert gas injection section 72 and the inert gas suction section 74 may be reversed with respect to the lamp chamber 66.
[0045]
Adjacent to the outside of the inert gas injection unit 72 and the inert gas suction unit 74, a utility supply unit and a control unit for supplying a required utility or control signal to each unit in the ultraviolet irradiation unit (UV) are accommodated. A utility unit 92 is provided.
[0046]
In the cleaning processing chamber 68, a stage 94 that can be moved horizontally and moved up and down for placing and supporting the substrate G is provided. In this embodiment, a stage 94 is mounted on a self-propelled stage driving unit 98 using a ball screw 96 so as to be vertically movable (Z direction in the figure), and the stage driving unit 98 is parallel to the ball screw 96 and the same. It is configured to reciprocate along the extending guide 100 in the Y direction of the drawing, that is, directly below the lamp chamber 66 in parallel with the lamp arrangement direction at a variable controllable speed.
[0047]
A plurality of (for example, six) lift pins 102 for vertically supporting the substrate G when the substrate G is loaded / unloaded through the stage 94 penetrates vertically. In this embodiment, each lift pin 102 is fixed at a predetermined height position for substrate transfer, and the stage 94 does not interfere with loading / unloading of the substrate G with respect to these fixed lift pins 102 when the substrate G is loaded / unloaded. It can be moved up and down by a lifting mechanism (not shown) between a lower limit height position Hb for retraction and an upper limit height position Ha indicated by a one-dot chain line for placing and supporting the substrate 94 by itself.
[0048]
The stage 94 is formed to be slightly larger in size than the substrate G, and a plurality of support pins (see FIG. 5) for supporting the substrate G are provided in a predetermined region (substrate mounting region) 94a near the center where the substrate G is mounted. (Not shown) and a vacuum chuck suction port (not shown) for sucking and holding the substrate G is provided. In FIG. 3, the lamp chamber 66 is positioned on the right side end portion 94b of the stage right next to the substrate mounting area 94a, more specifically, on the front right side of the stage moving direction (Y direction) as shown in FIG. An optical sensor 104 is provided for measuring the illuminance of ultraviolet rays applied to the substrate G on the stage 94.
[0049]
  In FIG. 3, the side of the cleaning processing chamber 68 adjacent to the origin position of the stage 94 in the Y direction.wallA shutter (door) 106 that can be opened and closed for loading / unloading the substrate G at a height position close to the upper end of the fixed lift pin 102 is attached. The shutter 106 faces the transport path 36 (FIG. 1) of the cleaning process unit 22, and the substrate G enters the cleaning processing chamber 68 from the transport path 36 through the shutter 104 with the main transport device 38 open. Carry in / out.
[0050]
  The side of the cleaning processing chamber 68wallAlternatively, one or a plurality of exhaust ports 108 are provided on the bottom surface, and each exhaust port 108 is connected to an exhaust system (not shown) such as an exhaust duct via an exhaust pipe 110. Further, an outside air inlet (not shown) may be provided at an appropriate location in the cleaning processing chamber 68.
[0051]
FIG. 5 shows the configuration of the control system in this ultraviolet irradiation unit (UV). The control unit 112 may be composed of a microcomputer and necessary peripheral circuits, and a built-in memory stores a necessary program for controlling each part and the whole of the unit, via an appropriate interface. These are connected to a main controller (not shown) that supervises the overall processing procedure of the coating and developing processing system and each part of a control system in the ultraviolet irradiation unit (UV).
[0052]
In this embodiment, main parts in the ultraviolet irradiation unit (UV) related to the control unit 112 are a shutter driving unit 114 for opening and closing the shutter 106 and a stage for driving the stage 94 up and down in the Z direction. The raising / lowering driving unit 116, the scanning driving unit 118 for horizontally driving or scanning driving the stage 94 in the Y direction, and the lamp power source unit 120 for lighting driving the ultraviolet lamps 64 (1) to 64 (n) in the lamp chamber 66. , An inert gas flow driving unit 122 for creating an inert gas flow under the ultraviolet irradiation window 62 of the lamp chamber 66, sensors 124 for detecting the state or amount of each part in the apparatus, and the like.
[0053]
The stage raising / lowering drive unit 116 and the scan drive unit 118 have, for example, servo motors as respective drive sources, and are provided in the stage drive unit 98. The inert gas flow drive unit 122 opens and closes on-off valves provided in the inert gas supply unit 80 of the inert gas injection unit 72 and the gas exhaust unit 88 of the inert gas suction unit 74, respectively. The sensors 112 include the optical sensor 104 installed at the right end 94 b of the stage 94.
[0054]
FIG. 6 shows a configuration of an illuminance adjusting unit for adjusting the illuminance of ultraviolet rays irradiated from the lamp chamber 66 onto the substrate G on the stage 94 to a predetermined value in the ultraviolet irradiation unit (UV). In this illuminance adjusting unit, the control unit 112 includes portions 128 to 138 excluding the optical sensor 104 and the stage lifting / lowering driving unit 116.
[0055]
An output signal (for example, photocurrent) of the optical sensor 104 is input to the illuminance measurement circuit 128. The illuminance measurement circuit 128 uses the value of the output signal of the optical sensor 104 and the offset d of the height position between the light receiving surface of the optical sensor 104 and the surface of the substrate G as variables, and the ultraviolet light on the surface of the substrate G on the stage 94. A measured value (or estimated value) E of illuminance is obtained by required signal processing or calculation processing. Here, with the substrate mounting surface 94a of the stage 94 as a reference surface, the height position Sh of the light receiving surface of the optical sensor 104 is constant, and the plate thickness Gt of the substrate G is currently flowing in this coating and developing processing system ( It is set in the plate thickness setting unit 130 as one of condition data or attribute data related to the substrate to be processed (under processing). Therefore, the height position offset d is given by d = Gt−Sh.
[0056]
The ultraviolet illuminance measurement value E obtained from the illuminance measurement circuit 128 is given to the illuminance comparison unit 132. The illuminance comparison unit 132 compares the ultraviolet illuminance measurement value E with the reference illuminance Es from the reference illuminance setting unit 134, and obtains a difference between them, that is, an error δE. Here, the reference illuminance Es may be set to an appropriate illuminance that can guarantee a desired ultraviolet cleaning effect under a predetermined scanning speed.
[0057]
In accordance with the illuminance error δE from the illuminance comparison unit 132, the stage elevating control unit 136 controls the stage elevating drive unit 116 so that the error δE approaches zero, and the stage 94 height position Ha for placing the substrate 94 on the stage 94. change. Thereby, when the ultraviolet illuminance measurement value E obtained from the illuminance measurement circuit 128 coincides with the reference illuminance Es, the variable adjustment of the stage height position is stopped.
[0058]
However, the stage elevating control unit 136 is provided on the stage 94 from position information indicating the stage height position from a predetermined position sensor (not shown) and the like, and substrate board thickness (Gt) data from the board thickness setting unit 130. The distance D between the substrate G and the ultraviolet irradiation window 62 of the lamp chamber 66 is monitored, and the maximum value Dmax and the minimum value Dmin are received from the maximum / minimum distance setting unit 138 for the distance D. When the interval D reaches the maximum value Dmax (for example, 7 mm) or the minimum value Dmin (for example, 3 mm) in the process of changing the height position of the stage 94 according to the illuminance error δE from the illuminance comparison unit 132, Therefore, the height adjustment of the stage 94 is forcibly stopped, and the interval D is limited or fixedly held at the maximum value Dmax or the minimum value Dmin.
[0059]
FIG. 7 shows a main operation procedure in the ultraviolet irradiation unit (UV). First, in response to an instruction from the main controller, each unit in the unit including the control unit 112 is initialized (step A1). During this initialization, the stage 94 is positioned at a predetermined origin position close to the shutter 106 in the Y direction, and is lowered to a retreat height position (Hb) in the Z direction.
[0060]
When the main transport device 38 (FIG. 1) transports the unprocessed substrate G from the cassette station (C / S) 10 to the front of the ultraviolet irradiation unit (UV), the control unit 112 controls the main transport device 38 and the substrate. The corresponding units are controlled so as to deliver G (step A2).
[0061]
More specifically, first, the shutter drive unit 114 is controlled to open the shutter 106. The main transfer device 38 has a pair of transfer arms. The substrate G before cleaning is placed on one transfer arm, and the other transfer arm is made empty (no substrate). When there is no cleaned substrate G in the ultraviolet irradiation unit (UV), the transfer arm that supports the substrate G before cleaning is directly extended into the cleaning processing chamber 68 through the open shutter 106, The uncleaned substrate G is transferred onto the fixed lift pins 102. When there is a cleaned substrate G in the ultraviolet irradiation unit (UV), first, the cleaned substrate G is unloaded with an empty transfer arm, and then the uncleaned substrate G is loaded in the same manner as described above. To do. As described above, when the substrate G to be subjected to the ultraviolet cleaning process in the ultraviolet irradiation unit (UV) is loaded and placed on the fixed lift pin 102 by the main transport device 38, the shutter 106 is closed.
[0062]
Next, the control unit 112 controls the stage raising / lowering driving unit 116 to raise the stage 94 to the reference height position Ha0 for placing the substrate (step A3). At this time, the suction of the vacuum chuck portion may be started while the stage 94 is raised so that the substrate G can be sucked and held simultaneously with the stage 94 reaching the reference height position Ha0 for placing the substrate. An appropriate margin may be set between the reference height position Ha0 for placing the substrate and the height position of the tip of the fixed lift pin 102.
[0063]
Next, the control unit 112 controls the lamp power source unit 120 to turn on the ultraviolet lamps 64 (1) to 64 (n) (step A4) and controls the inert gas flow driving unit 122 to control the inert gas. The injection part 72 and the inert gas suction part 74 are operated (step A5). As a result, the inert gas injection section 72 on the right side of the lamp chamber 66 feeds the inert gas (N2 gas) toward the lower side of the ultraviolet irradiation window 62, and the inert gas suction section 74 on the left side or downstream side of the lamp chamber 66. As the inert gas is sucked in, a flow (flow) of the inert gas is formed along the lower surface of the ultraviolet irradiation window 62 in parallel with the stage moving direction (Y direction).
[0064]
Next, the control unit 112 performs illuminance adjustment (step A6) before entering the ultraviolet cleaning process (step A7).
[0065]
FIG. 8 shows an illuminance adjustment procedure according to an embodiment. First, if it is necessary to align the illuminance measuring photosensor 104 with respect to the lamp chamber 66, this is performed (step B1). For example, if the optical sensor 104 on the stage right end 94b deviates from the ultraviolet irradiation area immediately below the ultraviolet irradiation window 62 at the origin position in the Y direction in FIG. 3, the stage 94 is moved somewhat in the Y direction to move the optical sensor. 104 may be placed in the ultraviolet irradiation region. In the Z direction, it is also possible to set a reference position Ha1 for adjusting illuminance different from the reference height position Ha0 for placing the substrate, and to adjust the stage 94 to the height position Ha1.
[0066]
After the optical sensor 104 is set at a predetermined position with respect to the lamp chamber 66 as described above, the illuminance measurement circuit 128 and the plate thickness setting unit 130 in the illuminance control unit (FIG. 6) perform ultraviolet rays on the substrate G on the stage 94. Is measured (step B2). Next, an error δE (δE = Es−E) of the illuminance measurement value E with respect to the reference illuminance Es is obtained by the illuminance comparison unit 132 and the reference illuminance setting unit 134 (step B3).
[0067]
Then, the stage lift control unit 136 determines the polarity and absolute value of the error δE (step B4), and controls the stage lift drive unit 116 to selectively variably adjust the height position of the stage 94 (step B5). To B11).
[0068]
In this embodiment, when δE <0, that is, when the illuminance measurement value E is larger than the reference illuminance Es, in principle, the stage height position Ha is lowered by a predetermined pitch (for example, 0.1 mm) to reduce the ultraviolet irradiation window. The distance D between 62 and the substrate G on the stage 94 is increased by the pitch (step B6), and the process returns to the illuminance measurement (steps B12 and B2). However, when the interval D reaches or exceeds the maximum value Dmax given by the maximum / minimum interval setting unit 138, the stage 94 is fixed at a height position at which the interval D stops at the maximum value Dmax ( Step B8). Normally, the interval D is adjusted to the vicinity of the maximum value Dmax when the lamp luminance on the lamp chamber 66 side is maximum, that is, immediately after the start of use or replacement of the ultraviolet lamps 62 (1) to 62 (n).
[0069]
When δE> 0, that is, when the illuminance measurement value E is smaller than the reference illuminance Es, in principle, the stage height position Ha is increased by a predetermined pitch (for example, 0.1 mm) and the ultraviolet irradiation window 62 and the stage 94 are increased. The distance D from the upper substrate G is narrowed by the pitch (step B10), and then the illuminance measurement is resumed (steps B12 and B2). However, when the interval D reaches the minimum value Dmin given by the maximum / minimum interval setting unit 138 or is likely to be divided, the stage 94 is fixed at a height position where the interval D stops at the minimum value Dmin ( Step B11). Further, the interval D is adjusted to the minimum value Dmin in this way because the luminance of the ultraviolet lamps 62 (1) to 62 (n) in the lamp chamber 66 is considerably reduced due to deterioration over time. An alarm for prompting maintenance such as lamp replacement may be issued (step B11). Further, when such an alarm is issued, the ultraviolet cleaning process may be stopped.
[0070]
When the illuminance measurement value E matches the reference illuminance Es (δE = 0), the process returns to the illuminance measurement without changing the height position Ha of the stage 94 (steps B5 and B2). Note that it is possible to give an appropriate width or range to the value of the reference illuminance Es, and when the measured illuminance value E falls within the range, it can be considered that both match (δE = 0).
[0071]
In this embodiment, since feedback is applied until the illuminance measurement value E matches the reference illuminance Es, illuminance adjustment with high accuracy can be performed. However, an adjustment target value of the interval or stage height position corresponding to the comparison error δE from the illuminance comparison unit 132 is calculated, and the height position of the stage 94 is adjusted by open loop control so as to reach the adjustment target value. It is also possible.
[0072]
While the above illuminance adjustment (step A6) is performed, an inert gas injection is performed in the gap P between the ultraviolet irradiation window 62 and the stage right end 94b under substantially the same conditions as in the ultraviolet irradiation cleaning process described later. An inert gas (N 2 gas) flows from the portion 72 toward the inert gas suction portion 74. This inert gas flow F (FIG. 3) functions to effectively exclude air, particularly oxygen, from the gap P. As a result, the degree to which ultraviolet rays (ultraviolet excimer light) emitted vertically downward from the ultraviolet irradiation window 62 of the lamp chamber 66 is absorbed by oxygen and reaches the light receiving surface of the optical sensor 104 is greatly reduced. The illuminance on the stage at the same interval D is greatly improved as compared to when there is no flow of inert gas. The inert gas flow F preferably flows closer to the ultraviolet irradiation window 62 side than to the stage side.
[0073]
After the above illuminance adjustment (step A6), an ultraviolet cleaning process is performed on the substrate G on the stage 96 (step A7). In order to perform this ultraviolet irradiation cleaning process, the control unit 112 causes the scanning driving unit 118 in the stage driving unit 98 to move the stage 94 one way or reciprocating in the Y direction between the origin position and the forward movement position indicated by the dotted line 94 ′. Let In this stage movement, the stage 94 crosses in the Y direction at the height position determined in the previous illuminance adjustment (step A6) just below the lamp chamber 66, so that the stage 94 is substantially vertically downward from the ultraviolet irradiation window 62 of the lamp chamber 66. Scanning from one end of the substrate to the other is performed in the direction opposite to the stage moving direction (Y direction) while irradiating ultraviolet rays having a wavelength of 172 nm irradiating the substrate G with an illuminance substantially equal to the reference illuminance.
[0074]
By irradiating the substrate G with ultraviolet rays having a wavelength of 172 nm in this way, oxygen existing in the vicinity of the substrate surface is changed to ozone O3 by the ultraviolet rays, and this ozone O3 is further excited by the ultraviolet rays to generate oxygen atom radicals. O * is generated. By this oxygen atom radical, the organic matter adhering to the surface of the substrate G is decomposed into carbon dioxide and water and removed from the substrate surface. The decomposed and vaporized organic matter is exhausted from the exhaust port 108.
[0075]
In such a scanning ultraviolet cleaning process, the amount of UV irradiation or the integrated light quantity on the substrate G is inversely proportional to the moving speed (scanning speed) of the stage 94. In other words, the higher the scanning speed F, the shorter the ultraviolet irradiation time for the substrate G and the smaller the ultraviolet irradiation amount, and the lower the scanning speed, the longer the ultraviolet irradiation time for the substrate G and the higher the ultraviolet irradiation amount. . Within a certain limit, the larger the amount of UV irradiation, the more organic matter is removed from the surface of the substrate G.
[0076]
In this embodiment, as described above, the illuminance adjustment (step A6) adjusts the illuminance of ultraviolet rays applied to the substrate G on the stage 94 from the lamp chamber 66 to a value near the reference illuminance, and then scan type as described above. Thus, even when the luminance of the ultraviolet lamps 64 (1) to 64 (n) in the lamp chamber 66 decreases due to deterioration over time, the ultraviolet irradiation time and the scanning speed are maintained at the set values. As a result (thus, without reducing the throughput), good cleaning process quality can be maintained.
[0077]
Further, during the ultraviolet cleaning process, as shown in FIG. 9, a gap between the ultraviolet irradiation window 62 of the lamp chamber 66 and the substrate G on the stage 94 by the inert gas injection unit 72 and the inert gas suction unit 74. An inert gas (N2 gas) flow F is formed in P. As in the previous illuminance adjustment (step A6), this inert gas flow F functions to effectively eliminate air, particularly oxygen, from the gap P. Note that oxygen adhering or floating near the surface of the substrate G is not so much excluded, and oxygen necessary for generating ozone for ultraviolet cleaning is sufficiently secured.
[0078]
As described above, oxygen in the air is removed from the gap P by the inert gas flow F, so that ultraviolet rays (ultraviolet excimer light) emitted vertically downward from the ultraviolet irradiation window 62 of the lamp chamber 66 are not attenuated so much. Can reach each part of the substrate surface. For this reason, the lamp input power can be reduced to a certain extent on the lamp chamber 66 side, and the life of the lamp 64 can be extended. Further, the ultraviolet reaction product generated in association with the ultraviolet cleaning process is sucked into the inert gas suction portion 74 so as to be caught in the flow F of the inert gas and discharged to the outside. Has the advantage that it is difficult to adhere.
[0079]
When the scanning ultraviolet cleaning process for the substrate G on the stage 94 as described above is completed, the control unit 112 controls the lamp power source unit 120 to turn off the ultraviolet lamps 64 (1) to 64 (n) (step). A8). Immediately thereafter, the inert gas flow driving unit 122 is controlled to stop the flow F of the inert gas immediately below the ultraviolet irradiation window 62 (step A9).
[0080]
Next, the control unit 112 returns the stage 94 to the start position (step A10). In this embodiment, first, the stage 94 is moved backward by the scanning drive unit 118, and then the vacuum chuck is turned off at the origin position in the Y direction, and then the stage 94 is retracted to a height position (Hb) by the stage lift drive unit 116. ) And the substrate G is supported by the fixed lift pins 102. In this way, all processes in the ultraviolet cleaning unit (UV) for one substrate G are completed, and the main transfer device 38 (FIG. 1) is waited for.
[0081]
When the UV cleaning process is performed in a scanning manner as in the above-described embodiment, the illuminance adjusting unit (FIG. 6) is used when the illuminance measuring optical sensor 104 on the stage 94 passes through the UV irradiation window 62 of the lamp chamber 66. It is also possible to measure or monitor the ultraviolet illuminance (distribution) directly under the ultraviolet irradiation window 62 by using the illuminance monitor function of FIG. With this illuminance monitoring function, the brightness of each of the ultraviolet lamps 64 (1) to 64 (n) in the lamp chamber 66 can be monitored from the stage 94 side, and a lamp with an abnormally low brightness or a lamp that cannot be lit can be detected.
[0082]
In the above-described embodiment, the scanning method is such that the lamp chamber 66 side is fixed and the stage 94 side is moved in parallel with the surface of the substrate G. However, a scanning method in which the stage 94 side is fixed at a predetermined position and the lamp chamber 66 side is moved in parallel with the surface of the substrate G is also possible.
[0083]
In addition, the relative movement between the lamp chamber 66 and the stage 94 for ultraviolet scanning can be realized by a rotational movement. FIG. 10 and FIG. 11 show examples of the configuration of the rotational scanning apparatus. In the figure, the same reference numerals are given to parts having the same configuration or function as those of the above-described embodiment. In this configuration example, a stage raising / lowering mechanism and a rotation mechanism (not shown) are provided in the stage driving unit 140, and when performing the ultraviolet irradiation process, the rotation mechanism is operated so that the stage 94 and the substrate G are placed on the stage center vertical axis O. It is made to rotate around at a predetermined speed. A configuration in which the stage 94 side is fixed and the lamp chamber 66 side is rotationally moved is also possible.
[0084]
According to such a rotational scanning method, the planar space of the stage 94 or the lamp chamber 66 can be minimized, so that the apparatus space can be reduced. Moreover, as shown in FIG. 11, the required length dimension of the ultraviolet lamps 64 (1) to 64 (n) in the lamp chamber 66 can be shortened.
[0085]
The configuration in the lamp chamber 66 and the cleaning processing chamber 68 in the above-described embodiment, particularly the ultraviolet irradiation window 62, the ultraviolet lamps 64 (1) to 64 (n), the stage 94, the stage driving units 98 and 140, the illuminance adjusting unit ( The configuration shown in FIG. 6) is an example, and various modifications can be made to each part.
[0086]
In the above embodiment, the illuminance measurement optical sensor 104 is arranged at a position closest to the substrate G on the stage 94, and the ultraviolet illuminance on the substrate G is measured based on the output signal of the optical sensor 104, so that the accuracy is high. Illuminance measurement can be performed. However, although the accuracy is lowered, it is possible to arrange such an illuminance measuring optical sensor 104 at another place, for example, outside the stage 94, or in the substrate mounting area 94a on the stage 94, the light receiving surface. It is also possible to expose and embed.
[0087]
In the above embodiment, in order to variably adjust the distance (illumination distance) between the lamp chamber 66 and the stage 94, the lamp chamber 66 is fixedly arranged, and the height position of the stage 94 is variably adjusted. However, conversely, a configuration in which the height position of the stage 94 is fixed and the height position of the lamp chamber 66 is variably adjusted is possible, or a configuration in which both positions are variably adjusted is also possible.
[0088]
In the above embodiment, since the illuminance measurement or the stage height position adjustment according to the thickness Gt of the substrate G placed on the stage 94 is performed, a more accurate illuminance adjustment can be realized. However, although the accuracy is low, practically sufficient illuminance adjustment is possible even if the distance (illumination distance) between the lamp chamber 66 and the stage 94 is variably adjusted ignoring the thickness Gt of the substrate G.
[0089]
The embodiment described above relates to an ultraviolet irradiation cleaning apparatus (UV). However, the substrate processing apparatus of the present invention can also be applied to processing for irradiating a substrate to be processed with ultraviolet light for purposes other than removal of organic contamination. For example, in the coating and developing treatment system as described above, the same ultraviolet irradiation apparatus as in the above embodiment can be used in the step of irradiating the substrate G with ultraviolet rays for the purpose of curing the resist after post-baking (step S13). The substrate to be processed in the present invention is not limited to an LCD substrate, but may be a semiconductor wafer, a CD substrate, a glass substrate, a photomask, a printed substrate, or the like.
[0090]
【The invention's effect】
As described above, according to the substrate processing apparatus of the present invention, it is possible to appropriately manage the illuminance of ultraviolet rays with respect to the substrate to be processed in the ultraviolet irradiation processing, and to stably maintain the processing quality and efficiency. Moreover, the window member for ultraviolet irradiation can be effectively protected from the ultraviolet reaction product.
[Brief description of the drawings]
FIG. 1 is a plan view showing a configuration of a coating and developing processing system to which a substrate processing apparatus of the present invention can be applied.
FIG. 2 is a flowchart showing a processing procedure in the coating and developing treatment system of the embodiment.
FIG. 3 is a perspective view showing a configuration of an ultraviolet irradiation unit of the embodiment.
FIG. 4 is a perspective view showing a mounting structure of an illuminance measuring optical sensor in the ultraviolet irradiation unit of the embodiment.
FIG. 5 is a block diagram illustrating a configuration of a control system of the ultraviolet irradiation unit according to the embodiment.
FIG. 6 is a block diagram illustrating a configuration example of an illuminance adjustment unit in the ultraviolet irradiation unit of the embodiment.
FIG. 7 is a flowchart showing a main operation procedure in the ultraviolet irradiation unit of the embodiment.
FIG. 8 is a flowchart showing a procedure for adjusting illuminance in the ultraviolet irradiation unit of the embodiment.
FIG. 9 is a partial side view showing the operation of the method of flowing an inert gas through the gap between the ultraviolet irradiation window and the substrate in the ultraviolet irradiation unit of the embodiment.
FIG. 10 is a perspective view showing a configuration of an ultraviolet irradiation unit according to another embodiment.
FIG. 11 is a plan view showing a main part of an ultraviolet irradiation unit according to another embodiment.
[Explanation of symbols]
38 Main transfer device
UV UV irradiation unit
62 UV irradiation window (quartz glass window)
64 (1), 64 (2), ..., 64 (n) UV lamp
66 Lamp room
68 Cleaning treatment room
72 Inert gas injection unit
74 Inert gas inlet
94 stages
94a Substrate placement area
94b Stage right end
98 Stage drive unit
104 Optical sensor
112 Control unit
116 Stage lift drive
118 Scan driver
122 Inert gas flow drive
128 Illuminance measurement circuit
130 Thickness setting section
132 Illuminance comparison part
134 Reference illuminance setting section
136 Stage Elevation Control Unit
138 Maximum / minimum interval setting section
140 Stage drive unit

Claims (11)

In a substrate processing apparatus for performing predetermined processing by irradiating a substrate to be processed with ultraviolet rays,
A mounting table for mounting and supporting the substrate;
And a window member for transmitting a plurality of lamps and ultraviolet emitting ultraviolet supplied with electric power, ultraviolet radiation for irradiating the ultraviolet rays emitted from the lamp to the substrate on the mounting table before through the window member Means,
An ultraviolet illuminance measuring means for measuring the illuminance of ultraviolet rays irradiated to the substrate on the mounting table from the ultraviolet irradiation means, having an optical sensor provided on the mounting table at a position not interfering with the substrate ;
Before starting the ultraviolet irradiation process on the substrate, an irradiation distance adjusting unit that variably adjusts the distance between the ultraviolet irradiation unit and the mounting table according to the ultraviolet illuminance measurement value obtained from the ultraviolet illuminance measuring unit,
During the ultraviolet irradiation process, the mounting table and the mounting table are arranged so that the ultraviolet light from the ultraviolet irradiation unit scans the processing surface of the substrate on the mounting table and at the same time the optical sensor passes under the window member. Driving means for moving either one or both of the ultraviolet irradiation means in a predetermined direction;
During the ultraviolet irradiation process, the ultraviolet illuminance distribution under the window member is measured or monitored based on the ultraviolet illuminance measurement value obtained from the ultraviolet illuminance measuring means, and a lamp having an abnormally low brightness or a lamp that cannot be lit is detected. A substrate processing apparatus having ultraviolet illuminance monitoring means for performing the processing.   The said irradiation distance adjustment means contains the means to variably adjust the distance between the said ultraviolet irradiation means and the said mounting base according to the plate | board thickness of the said board | substrate mounted on the said mounting base. Substrate processing equipment. The irradiation distance adjusting means is
A reference illuminance setting means for setting a desired reference illuminance;
2. A relative position adjusting unit that compares the ultraviolet illuminance measurement value with the reference illuminance and adjusts a relative position between the mounting table and the ultraviolet irradiating unit so that the comparison error approaches zero. Alternatively, the substrate processing apparatus according to claim 2. The irradiation distance adjusting means is
Maximum interval setting means for setting a maximum value for the interval between the window member and the mounting table or the substrate;
The substrate processing apparatus according to claim 1, further comprising: a maximum interval limiting unit that limits the interval to the maximum value when the interval is likely to exceed the maximum value in the variable adjustment of the interval. . The irradiation distance adjusting means is
Minimum interval setting means for setting a minimum value for the interval between the window member and the mounting table or the substrate;
Minimum interval limiting means for limiting the interval to the minimum value when the interval is likely to divide the minimum value in the variable adjustment of the interval;
The substrate processing apparatus according to claim 1, further comprising: an alarm unit that generates an alarm when the interval is likely to divide the minimum value.   The substrate processing apparatus according to claim 1, wherein the optical sensor is disposed at a position in front of the substrate in the scanning direction.   The substrate processing apparatus according to claim 1, wherein each of the plurality of lamps is a cylindrical dielectric barrier discharge lamp, and is arranged in a horizontal direction orthogonal to the longitudinal direction of the lamp. The substrate processing apparatus according to claim 1, further comprising an inert gas flow forming unit that forms a flow of an inert gas in a gap between the window member and the substrate on the mounting table. The inert gas flow forming means comprises:
An inert gas injection means for injecting an inert gas from the vicinity of the window member toward the gap between the window member and the substrate on the mounting table facing the mounting table;
An inert gas suction means for sucking the inert gas that has passed through the gap at a position opposite to the inert gas injection means across the window member;
The substrate processing apparatus according to claim 8, comprising: 10. The substrate according to claim 9, wherein the inert gas injection unit and the inert gas suction unit are respectively disposed on a front side and a rear side of the window member in the movement direction when viewed from the mounting table side. Processing equipment. Said drive means, any one of claims 1 to 10 having a rotational drive means for rotating movement on the other hand the second position while either fixed in the first position of the mounting table or the ultraviolet light irradiation means The substrate processing apparatus according to item .

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