JP4417205B2 - Substrate processing equipment - Google Patents

Description

  The present invention relates to a technique for a substrate processing apparatus that applies a processing liquid to a surface of a substrate by scanning the substrate while discharging the processing liquid from a nozzle. More specifically, the present invention relates to a technique for detecting an object with high accuracy in order to prevent the nozzle from interfering with a foreign object (object) in scanning with the nozzle.

  In the manufacturing process of liquid crystal glass square substrates, semiconductor wafers, film liquid crystal flexible substrates, photomask substrates, and color filter substrates (hereinafter simply referred to as “substrates”), a processing solution is applied to the surface of the substrate. A coating apparatus (substrate processing apparatus) is used. As coating apparatuses, there are known a slit coater that performs slit coating using a slit nozzle having a slit-like discharge section, and a slit / spin coater that rotates the substrate after the slit coating is performed once.

In such a coating apparatus, the slit nozzle and the substrate are moved relative to each other in a state where the tip of the slit nozzle and the substrate are close to each other to apply the treatment liquid. When the substrate rises due to foreign matter sandwiched between the stage and the stage,
(1) The slit nozzle is damaged. (2) The substrate is cracked or the substrate is scratched. (3) The coating is performed while dragging foreign matter, thereby causing problems such as application failure.

  Therefore, conventionally, in a coating apparatus using a slit nozzle, it is determined whether or not there is an object (interference object) in contact with the slit nozzle by performing a foreign substance inspection. Techniques for avoiding collisions have been proposed. Such a technique is described in Patent Document 1, for example.

  The coating apparatus described in Patent Document 1 detects an object using a transmission type laser sensor (a sensor that detects transmitted laser light), and when the laser sensor detects the object, By forcibly terminating the coating process, the slit nozzle and the object are prevented from contacting each other.

  12 to 15 are conceptual diagrams for explaining the principle by which the transmission laser sensor 100 used in the coating apparatus described in Patent Document 1 detects an object. The transmissive laser sensor 100 receives laser light emitted from the light projecting unit 101 by a light receiving unit 102 disposed on the optical axis so as to face the light projecting unit 101, and the presence or absence of an object is determined by the amount of light received. It is a sensor that detects

  In the laser sensor 100, as shown in FIG. 12, when any object (object) is present on the optical path, the laser light is shielded on the optical path by the object. Therefore, as shown in FIG. 13, the amount of laser light received by the light receiving unit 102 decreases. Therefore, the laser sensor 100 can determine that an object exists on the optical path when the amount of light received by the light receiving unit 102 is smaller than the predetermined threshold value Q.

JP 2002-001195 A

  However, unlike a large-sized He—Ne gas laser or the like, in a small-sized semiconductor laser, as shown in FIGS. 12 and 14, the laser beam is in a focused position (a position where the luminous flux is most focused: an example shown here). 2 has a property that its diameter increases as it shifts in the optical axis direction from the irradiation start position of the light projecting unit 101. Therefore, as shown in FIG. 14, when the object is at a position far from the light projecting unit 101 (a position where the diameter is widened), the laser beam is received by the light receiving unit 102 with almost no shielding. Become. In this case, the amount of laser light received by the light receiving unit 102 is larger than the threshold value Q as shown in FIG. 15, so that there is an object of a size that should be detected originally. A situation occurs in which the object cannot be detected. When a general transmission type laser sensor is used, the range in which the accuracy required for the coating process can be maintained is that the distance between the light projecting unit 101 and the light receiving unit 102 is up to about 500 mm.

  That is, in the coating apparatus described in Patent Document 1, for example, due to the increase in size of the substrate, in the laser sensor 100, it is necessary to dispose the light projecting unit 101 and the light receiving unit 102 relatively apart (for detection). In the case where the optical path of the laser beam becomes longer, the detection accuracy for the region on the light receiving unit 102 side is lowered.

  Further, the laser sensor 100 performs detection based on the attenuation amount. Therefore, there is a problem that the light projecting unit 101 and the light receiving unit 102 have to be accurately arranged to face each other, and adjustment work of the laser sensor 100 takes time.

  Further, in order to improve the sensitivity of the laser sensor 100, it is necessary to determine that a foreign object has been detected even for a slight attenuation. However, in the conventional apparatus, the light projecting unit 101 and the light receiving unit 102 may be displaced due to vibration during movement, which may attenuate the amount of received laser light. That is, the conventional apparatus has a problem that erroneous detection occurs when the sensitivity is increased.

  The present invention has been made in view of the above problems, and an object thereof is to reduce a burden on an operator while preventing a decrease in detection accuracy of an object.

In order to solve the above-mentioned problem, the invention of claim 1 is a substrate processing apparatus for applying a predetermined processing liquid to a substrate, wherein the holding means for holding the substrate and the substrate held by the holding means An ejection unit that ejects a predetermined processing liquid, a moving unit that relatively moves the substrate held by the holding unit and the ejection unit, and performs scanning by the ejection unit with respect to the substrate; and the ejection At least one detection means for detecting an object that may interfere with the ejection means during scanning of the means, and a control means for controlling the moving means based on a detection result by the detection means, detection means includes a light projecting unit for irradiating in a direction parallel to the surface of the substrate held a laser beam to said holding means, upward from directly receiving the light position of the irradiated laser beam by the light projecting unit Disposed off position, the laser beam reflected by the object of the irradiated laser beam by the light projecting unit and a light receiving portion for receiving the detection light, the detection means, the light receiving portion is the When detecting light is received, a detection result indicating that the object is detected is transmitted to the control means.

  The invention of claim 2 is the substrate processing apparatus according to the invention of claim 1, wherein the light receiving section is arranged at a position shifted in a direction substantially perpendicular to the scanning direction of the ejection means. Features.

The invention according to claim 3 is the substrate processing apparatus according to claim 1 or 2 , wherein the auxiliary detection means detects an object that may interfere with the ejection means during scanning of the ejection means. The auxiliary detection means is disposed at a position facing the light projecting unit or the auxiliary light projecting unit, and receives the direct light of the laser light emitted from the light projecting unit or the auxiliary light projecting unit. An auxiliary light receiving unit, and the auxiliary detection unit sends a detection result indicating that the object has been detected to the control unit when the received light amount of the direct light in the auxiliary light receiving unit is a predetermined threshold value or less. The control means controls the moving means according to the detection result of the detection means and the detection result of the auxiliary detection means.

The invention of claim 4 is the substrate processing apparatus according to any one of claims 1 to 3 , comprising two or more of the at least one detection means, the light projecting unit of one detection means, The light projecting portions of other detection means are separately arranged on both sides of the substrate held by the holding means.

In the invention according to any one of claims 1 to 4 , the light projecting unit is disposed at a position deviating upward from the position of receiving direct light of the laser light irradiated in parallel to the surface of the substrate. It has a light receiving part that receives laser light reflected by the object among the irradiated laser light as detection light, and when the light receiving part receives the detection light, the detection result that the object is detected is sent to the control means. By transmitting, since the position of the light receiving unit may be relatively ambiguous, the burden on the adjustment work is reduced. Further, since the object can be detected if the light receiving unit receives even a small amount of detection light, erroneous detection is suppressed as compared with the case where detection is performed according to the amount of attenuation of the amount of received light, so that accuracy is improved.

  In the second aspect of the invention, the light receiving unit is disposed at a position that is substantially perpendicular to the scanning direction of the ejection unit, thereby suppressing the influence of vibration caused by scanning by the ejection unit. . Accordingly, erroneous detection can be suppressed, and an accurate detection result can be obtained.

According to a third aspect of the present invention, there is provided an auxiliary light receiving unit that is disposed at a position facing the light projecting unit or the auxiliary light projecting unit and that receives the direct light of the laser light emitted from the light projecting unit or the auxiliary light projecting unit. When the amount of direct light received by the auxiliary light receiving unit is equal to or less than a predetermined threshold value, the range of detectable objects is expanded by assuming that the objects are detected.

In the invention according to claim 4 , the light projecting portion of one detecting means and the light projecting portion of the other detecting means are arranged separately on both sides of the substrate held by the holding means, respectively. The object can be detected without being affected by the width of the object.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.

<1. First Embodiment>
<1.1 Description of configuration>
FIG. 1 is a front view of a substrate processing apparatus 1 according to a first embodiment of the present invention. FIG. 2 is an enlarged view of the periphery of the detection unit 45 in the substrate processing apparatus 1. In FIGS. 1 and 2, for convenience of illustration and explanation, the Z-axis direction is defined as the vertical direction and the XY plane is defined as the horizontal plane, but these are defined for convenience in order to grasp the positional relationship. However, each direction described below is not limited. The same applies to the following figures.

  The substrate processing apparatus 1 uses a rectangular glass substrate for manufacturing a screen panel of a liquid crystal display device as a substrate 90 to be processed. In the process of selectively etching an electrode layer or the like formed on the surface of the substrate 90, the substrate 90 is processed. It is comprised as a coating device which apply | coats a resist liquid to the surface of this. Therefore, in this embodiment, the slit nozzle 41 discharges the resist solution to the substrate 90. In addition, the substrate processing apparatus 1 can be modified and used not only as a glass substrate for a liquid crystal display device but also as a device for applying a processing liquid (chemical solution) to various substrates for a flat panel display. Further, the shape of the substrate 90 is not limited to a rectangular shape.

  The substrate processing apparatus 1 includes a stage 3 that functions as a holding table for placing and holding the substrate to be processed 90 and also functions as a base for each attached mechanism. The stage 3 is made of an integral stone having a rectangular parallelepiped shape, and its upper surface (holding surface 30) and side surfaces are processed into flat surfaces.

  The upper surface of the stage 3 is a horizontal plane and serves as a holding surface 30 for the substrate 90. A large number of vacuum suction ports (not shown) are distributed and formed on the holding surface 30. While the substrate 90 is processed in the substrate processing apparatus 1, the vacuum suction port sucks the substrate 90, whereby the stage 3 holds the substrate 90 in a predetermined horizontal position.

  Above the stage 3, a bridging structure 4 is provided that extends substantially horizontally from both sides of the stage 3. The bridging structure 4 is mainly composed of a nozzle support portion 40 that uses carbon fiber resin as an aggregate, elevating mechanisms 43 and 44 that support both ends thereof, and a moving mechanism 5.

  A slit nozzle 41 and a gap sensor 42 are attached to the nozzle support portion 40.

  The slit nozzle 41 extending in the horizontal Y-axis direction is connected to a discharge mechanism (not shown) including a pipe for supplying a chemical solution (resist solution) to the slit nozzle 41 and a resist pump. The slit nozzle 41 is supplied with a resist solution by a resist pump and scans the surface of the substrate 90, thereby discharging the resist solution to a predetermined region on the surface of the substrate 90 (hereinafter referred to as “resist application region”). To do.

  The gap sensor 42 is attached to the nozzle support portion 40 of the bridging structure 4 at a position facing the surface of the substrate 90, and is located between a certain direction (−Z direction) (for example, the substrate 90 and the resist film). The distance (gap) is detected, and the detection result is transmitted to the control unit 7.

  Thereby, the control unit 7 can detect the distance between the surface of the substrate 90 and the slit nozzle 41 based on the detection result of the gap sensor 42. The substrate processing apparatus 1 according to the present embodiment includes two gap sensors 42. However, the number of gap sensors 42 is not limited to this, and more gap sensors 42 may be provided. .

  The elevating mechanisms 43 and 44 are divided on both sides of the slit nozzle 41 and are connected to the slit nozzle 41 by the nozzle support portion 40. The elevating mechanisms 43 and 44 are used for moving the slit nozzle 41 in translation and adjusting the posture of the slit nozzle 41 in the YZ plane.

  At both ends of the bridging structure 4, moving mechanisms 5 arranged separately along the edge sides on both sides of the stage 3 are fixed. The moving mechanism 5 mainly includes a pair of AC coreless linear motors (hereinafter simply referred to as “linear motors”) 50 and a pair of linear encoders 51.

  Each linear motor 50 includes a stator and a mover (not shown), and a driving force for moving the bridging structure 4 (slit nozzle 41) in the X-axis direction by electromagnetic interaction between the stator and the mover. Is a motor that generates Further, the moving amount and moving direction of the linear motor 50 can be controlled by a control signal from the control unit 7.

  The linear encoder 51 includes a scale unit and a detector (not shown), detects the relative positional relationship between the scale unit and the detector, and transmits the relative positional relationship to the control unit 7. Each detector is fixed to both ends of the bridging structure 4, and the scale portion is fixed to both sides of the stage 3. Thereby, the linear encoder 51 has a function of detecting the position of the bridging structure 4 in the X-axis direction.

  Detection units 45 are further attached to the moving mechanisms 5 fixed on both sides of the bridging structure 4. In the substrate processing apparatus 1 according to the present embodiment, the detection unit 45 that detects an object includes two detection sensors 450 and 451 and one auxiliary detection sensor 452.

  FIG. 3 is a plan view showing the positional relationship between the scanning range E0 of the slit nozzle 41 and the detection unit 45. As shown in FIG. FIG. 4 is a right side view showing the arrangement relationship between the slit nozzle 41 and the detection unit 45, and FIG. 5 is a left side view showing the arrangement relationship between the slit nozzle 41 and the detection unit 45.

  The scanning range E0 is a scanning range of the slit nozzle 41 on the substrate. More specifically, when the moving mechanism 5 moves in the X-axis direction, the substrate 90 and the slit in the trajectory area (which becomes a planar area) drawn by the lower end (end in the −Z direction) of the slit nozzle 41. This is a region that faces the lower end of the nozzle 41 in a state of being closest (gap when applying the resist solution). That is, the scanning range E0 is an area where the slit nozzle 41 may come into contact with the object during scanning by the slit nozzle 41. In the substrate processing apparatus 1, the slit nozzle 41 is moved to various positions by the moving mechanism 5. However, when the elevating mechanisms 43 and 44 are moved while maintaining the slit nozzle 41 at a sufficiently high position, When moving the position not facing the substrate 90, the slit nozzle 41 does not interfere with the object.

  The object is an object that is detected in the scanning range E0, and the slit nozzle 41 may interfere with the scanning range E0 during scanning. Actually, the substrate 90 itself may be a target object in addition to foreign substances such as particles. This is because if a foreign substance exists between the stage 3 and the substrate 90, the substrate 90 rises and becomes an object of the slit nozzle 41.

  The detection unit 45 is disposed at a front position with respect to the slit nozzle 41 in the scanning direction (the moving direction when the slit nozzle 41 moves in the scanning range E0, which is the (−X) direction in the present embodiment). The object is detected while moving in the same direction as the slit nozzle 41 moves in the X-axis direction. The relative distance between the detection unit 45 and the slit nozzle 41 is set according to the speed at which the slit nozzle 41 moves by the moving mechanism 5 and the calculation speed of the control unit 7. In other words, when the control unit 7 controls the moving mechanism 5 according to the detection result of the detection unit 45, the distance between the object and the slit nozzle 41 can be sufficiently avoided.

  The detection direction of the detection unit 45 is the Y-axis direction, and the detection sensors 450 and 451 and the auxiliary detection sensor 452 are arranged in the X-axis direction. The positions of the detection sensors 450 and 451 and the auxiliary detection sensor 452 in the Z-axis direction can be adjusted by the operator.

  Each of the detection sensors 450 and 451 and the auxiliary detection sensor 452 includes a light projecting unit (light projecting units 450a, 451a, and 452a) and a light receiving unit (light receiving units 450b, 451b, and 452b). Each of the light projecting portions 450a, 451a, and 452a in the present embodiment uses a small semiconductor laser that irradiates spot-type laser light, but is not limited thereto. For example, you may use what irradiates a slit type laser beam.

  The detection sensors 450 and 451 are sensors that detect an object depending on whether or not the light receiving units 450b and 451b receive the laser light emitted from the light projecting units 450a and 451a.

  As shown in FIG. 3, the light projecting unit 450 a is disposed on the (−Y) side of the substrate 90, and the light receiving unit 450 b is disposed on the (+ Y) side of the substrate 90. On the other hand, the light projecting unit 451a is disposed on the (+ Y) side of the substrate 90, and the light receiving unit 451b is disposed on the (−Y) side of the substrate 90. That is, in the substrate processing apparatus 1 according to the present embodiment, the light projecting unit 450 a of the detection sensor 450 and the light projecting unit 451 a of the detection sensor 451 are arranged separately on both sides of the substrate 90. As a result, the detection sensor 450 emits laser light in the (+ Y) direction, and the detection sensor 451 emits laser light in the (−Y) direction.

  As shown in FIGS. 4 and 5, the light receiving portions 450b and 451b of the detection sensors 450 and 451 are arranged so as to be shifted in the (+ Z) direction from the height position in the Z-axis direction of the light projecting portions 450a and 451a. ing. The light projecting units 450a and 451a irradiate laser light in a direction along the Y axis (may be slightly tilted in the (−Z) direction).

  FIG. 6 is a diagram illustrating a locus of laser light when an object is not present during detection by the detection sensor 450. FIG. 7 is a diagram illustrating a locus of laser light when an object is present during detection by the detection sensor 450. The principle by which the detection sensor 450 in the present embodiment detects an object will be described with reference to FIGS. Note that the detection sensor 451 is the same in principle as that of the detection sensor 450 except that the laser light irradiation direction is different, and the description thereof will be omitted.

  As shown in FIG. 6, the light receiving unit 450b is arranged at a position deviating in the (+ Z) direction from the position of receiving the direct light of the laser light emitted by the light projecting unit 450a. That is, when there is no object, the laser light emitted from the light projecting unit 450a does not enter the light receiving unit 450b. On the other hand, as shown in FIG. 7, when an object is present, part of the laser light emitted by the light projecting unit 450a is reflected by the object, and the light receiving unit 450b receives the reflected light.

  That is, the detection sensors 450 and 451 in the present embodiment are laser sensors that use the laser light reflected by the object as detection light, and a signal indicating the amount of detection light received by the light receiving units 450b and 451b. This is transmitted to the control unit 7.

  Although details will be described later, the control unit 7 determines that the object cannot be detected when the received light amount transmitted from the detection sensors 450 and 451 is “0”, and the received light amount is larger than “0”. It is determined that an object has been detected.

  As shown in FIG. 7, even if an object exists and a part of the laser light hits the object and is irregularly reflected, the object is usually small compared to the spot diameter of the laser light, and most of them are Follow the trajectory as direct light. Therefore, in the conventional transmission type laser sensor, the light receiving unit receives a relatively large amount of direct light even when an object is present. For this reason, the attenuation of the amount of received light due to the direct light being shielded by the object is very small. Further, when the size of the substrate 90 is increased and the distance between the light projecting unit and the light receiving unit is increased, the spot diameter of the laser beam is increased (see FIGS. 12 and 14). In this case, the amount of attenuation of the amount of light received by being shielded by the object is further reduced.

  On the other hand, since the sensor moves together with the slit nozzle, the laser beam is slightly shaken by vibration accompanying the movement. As a result, when the laser light (direct light) from the light projecting unit deviates from the light receiving unit, the amount of light received by the light receiving unit is attenuated, and it is determined that the object has been detected in the conventional apparatus. In other words, since the attenuation when the target is present is very small, it can be distinguished from the attenuation of the received light caused by being shielded by the target and the attenuation of the received light caused by the movement (vibration) of the sensor. However, there is a possibility that erroneous detection may occur in the conventional apparatus. When erroneous detection occurs frequently, the slit nozzle stops each time, and there is a problem that throughput is lowered.

  However, in the substrate processing apparatus 1 according to the present embodiment, the light receiving portions 450b and 451b are arranged at positions away from the positions where the direct light of the laser light is received, and the presence / absence of the object is detected by the presence / absence of the detection light. . That is, erroneous detection can be suppressed as compared with the conventional method of detecting the presence or absence of an object based on the amount of attenuation of the amount of received light.

  In addition, the light receiving unit 450b is disposed at a position that is substantially perpendicular to the scanning direction (X-axis direction) of the slit nozzle 41 from the position where the direct light of the laser light emitted by the light projecting unit 450a is received. ing. The vibration of the laser beam due to the vibration occurs mainly in the scanning direction of the slit nozzle 41, and the vibration in the Z-axis direction is relatively small. Accordingly, the erroneous detection due to vibration is further suppressed by arranging the light receiving unit 450b at such a position.

  FIG. 8 is a diagram illustrating a case where the detection sensor 450 detects an object at a position close to the light receiving unit 450b. When the object is present at a position close to the light receiving unit 450b, the reflected light LFL of the laser light emitted from the light projecting unit 450a passes through a relatively low position in the Z-axis direction at the position of the light receiving unit 450b. . In particular, when the substrate 90 is large, the distance between the light projecting unit 450a and the light receiving unit 450b is long. Therefore, in order to receive the reflected light LFL, the light receiving unit 450b must be adjusted to a relatively low position. The direct light DRL of the laser light emitted from the light unit 450a is received. Since the detection sensor 450 cannot distinguish between the direct light DRL and the reflected light LFL, there is a possibility that the object cannot be detected in such a case.

  In order to prevent this, the light receiving portion 450b may be disposed at a position relatively distant from the end portion of the substrate 90 in the (+ Y) direction. However, in consideration of the footprint of the substrate processing apparatus 1, the light receiving unit 450 b is preferably installed in the vicinity of the end of the substrate 90.

  Therefore, in the substrate processing apparatus 1 according to the present embodiment, when an object is present at a position as shown in FIG. 8, the detection is performed by the detection sensor 451 that emits laser light from the (+ Y) direction. Since the object existing on the (+ Y) side and the light receiving unit 451b are sufficiently far away from each other, the light receiving unit 451b exists on the (+ Y) side even if the light receiving unit 451b is installed at a sufficiently high position where it does not directly receive light. It is possible to receive the laser beam reflected by the target object.

  As described above, the light projecting unit 450a of the detection sensor 450 and the light projecting unit 451a of the detection sensor 451 are separately arranged on both sides of the substrate 90 held on the stage 3, thereby detecting the detection sensor 450 and the detection sensor 450. The sensor 451 functions in a complementary manner, and an object within the scanning range E0 can be detected without being affected by the width of the substrate 90.

  As shown in FIGS. 4 and 5, the auxiliary detection sensor 452 has the light projecting unit 452a and the light receiving unit 452b disposed at substantially the same height position (position in the Z-axis direction), and the light projecting unit 452a and the light receiving unit 452b. And are arranged so as to face each other. The auxiliary detection sensor 452 in this embodiment detects an object based on the amount of attenuation of the amount of laser light received by the light receiving unit 452b by shielding the laser light emitted by the light projecting unit 452a from the object. It is a transmission type laser sensor to detect. That is, the principle of detecting an object is the same as that of the laser sensor 100 (see FIGS. 12 and 13) used in the conventional apparatus. However, unlike the conventional apparatus, the threshold for detecting an object is set to be relatively low (a large amount of attenuation), and is set so as not to be erroneously detected by the degree of attenuation due to vibration. In other words, the auxiliary detection sensor 452 is a sensor that detects a relatively large object, cannot detect a small object, and functions as a sensor with coarse detection accuracy.

  The detection sensor 450 cannot detect the object unless the laser beam reaches the side (+ Y side) where the light receiving unit 450b is disposed. Similarly, the detection sensor 451 cannot detect the object unless the laser beam reaches the side (−Y side) where the light receiving unit 451b is disposed. For example, when there is a large object that completely blocks the laser light, the laser light emitted from either of the light projecting units 450a and 451a does not reach the light receiving units 450b and 451b. As described above, when there is an object larger than expected, the control unit 7 may erroneously recognize that the object does not exist.

  Therefore, in the substrate processing apparatus 1 according to the present embodiment, an auxiliary detection sensor 452 is provided to detect a large target object that blocks the laser beam. Thus, by preventing oversight of the object, the substrate processing apparatus 1 can detect the object with higher accuracy. Although the threshold value of the auxiliary detection sensor 452 has been described as being set relatively low, in the extreme, only when the amount of light received by the light receiving unit 452b is “0” (when completely blocked), You may make it judge that the target object was detected.

  Returning to FIG. 1, the control unit 7 processes various data according to the program. The control unit 7 is connected to each mechanism of the substrate processing apparatus 1 by cables (not shown), and in response to inputs from the gap sensor 42, the linear encoder 51, the detection unit 45, and the like, the stage 3, the elevating mechanisms 43 and 44, and Each component such as the moving mechanism 5 is controlled.

  In particular, the control unit 7 monitors whether each of the light receiving units 450b and 451b has received the laser beam based on the input from the detection sensors 450 and 451, and when one of them receives the laser beam, It is determined that an object has been detected.

  The control unit 7 calculates the amount of laser light received by the light receiving unit 452b based on the input from the auxiliary detection sensor 452, and when the received light amount obtained by the calculation is smaller than a preset threshold, It is determined that an object exists within E0.

  In the substrate processing apparatus 1 according to the present embodiment, when the control unit 7 determines that an object exists, the control unit 7 regards the object as an interference object that contacts the slit nozzle 41. And in order to avoid the contact with the said target object and the slit nozzle 41, the moving mechanism 5 (linear motor 50) is controlled, and the scanning by the slit nozzle 41 is stopped. Note that the control operation of the control unit 7 when an object is detected will be described later.

  The control unit 7 is connected to an operation unit (operation panel, keyboard, etc.) and a display unit (liquid crystal display, display buttons, etc.) not shown, receives instructions from the operator via the operation unit, and displays the display unit. By displaying necessary data, the operator is notified of the state of the substrate processing apparatus 1 and the like.

  The above is description of the structure and function of the substrate processing apparatus 1 in this Embodiment.

<1.2 Adjustment work>
In the substrate processing apparatus 1, the position adjustment operation of the detection sensors 450 and 451 and the auxiliary detection sensor 452 in the Z-axis direction is performed by the operator before performing the process of applying the resist solution to the substrate 90. This position adjustment is performed using a micro gauge having a positioning accuracy of 10 μm or less.

  The light projecting portions 450 a and 451 a of the detection sensors 450 and 451 are adjusted in position in the Z-axis direction so that the laser light to be irradiated follows the surface of the substrate 90. In this case, since the laser beam may be partially shielded by the substrate 90, the position adjustment in the Z-axis direction can tolerate an error corresponding to the spot diameter of the laser beam and should be adjusted relatively vaguely. Can do. That is, since a strict adjustment work is not necessary, the burden of the adjustment work is reduced.

  This also means that the detection sensors 450 and 451 can cope with a change in the thickness of the substrate 90 corresponding to the spot diameter. That is, even when processing substrates 90 having different thicknesses, readjustment is not necessary if the change in thickness is within a predetermined range, so that the burden of adjustment work can be reduced.

  When the positions of the light projecting parts 450a and 451a are determined, the light receiving parts 450b and 451b of the detection sensors 450 and 451 are once set at positions to receive the direct light of the laser light emitted from the light projecting parts 450a and 451a. Is done. At this time, the light receiving portions 450b and 451b only need to receive a part of the laser light (direct light), so this position adjustment may be relatively ambiguous. Next, the light receiving portions 450b and 451b are gradually moved in the (+ Z) direction, and the light receiving portions 450b and 451b are fixed at positions where laser light is not received. Thus, even in the position adjustment work of the light receiving portions 450b and 451b, the work burden is reduced as compared with the conventional apparatus.

  The light projecting unit 452a of the auxiliary detection sensor 452 has an optical path of the laser beam in the (+ Z) direction from the surface of the substrate 90 so that the substrate 90 held in a normal state on the stage 3 is not erroneously detected as an object. The position is adjusted to be the position. That is, the position adjustment is performed based on the holding surface 30 of the stage 3 while taking the thickness of the substrate 90 into consideration. At this time, it is preferable to adjust in consideration of the uniformity of the thickness of the substrate 90 (usually within ± 1% of the design thickness) and the flat processing accuracy of the holding surface 30. Thus, the optical path of the laser light is adjusted so as to be on the (+ Z) side with respect to the surface of the substrate 90.

  Further, in the substrate processing apparatus 1, in order to prevent the contact between the slit nozzle 41 and the target object, the target object existing on the (−Z) side from the scanning range E0 must be detected. Accordingly, the position of the light projecting portion 452a in the Z-axis direction is adjusted so that the range scanned by the laser light includes a region on the (−Z) side of the scanning range E0.

  When the position of the light projecting unit 452a is determined, the light receiving unit 452b of the auxiliary detection sensor 452 is adjusted to be substantially the same as the position of the light projecting unit 452a in the Z-axis direction. However, in the substrate processing apparatus 1 in the present embodiment, the detection accuracy of the auxiliary detection sensor 452 is set roughly. Therefore, it is not necessary to strictly adjust the position of the light receiving unit 452b so that almost 100% of the laser light emitted from the light projecting unit 452a is received as in the conventional apparatus. That is, it is sufficient that the laser beam is adjusted so that a part of the spot of the laser beam is received by the light receiving unit 452b, and the burden of adjustment work is reduced as compared with the conventional case.

<1.3 Explanation of operation>
Next, the operation of the substrate processing apparatus 1 will be described. FIG. 9 and FIG. 10 are flowcharts showing operations in the coating process of the substrate processing apparatus 1. The operation control of each unit shown below is performed by the control unit 7 unless otherwise specified.

  In the substrate processing apparatus 1, the resist solution coating process is started when the substrate 90 is transported to a predetermined position by an operator or a transport mechanism (not shown). The instruction for starting the processing may be input by operating the operation unit by the operator when the conveyance of the substrate 90 is completed.

  First, the stage 3 sucks and holds the substrate 90 at a predetermined position on the holding surface 30. Next, the gap sensor 42 is moved to the measurement start position for measuring the gap with the substrate 90 by moving the slit nozzle 41 (step S11). This operation is performed by the elevating mechanisms 43 and 44 adjusting the height position of the slit nozzle 41 to the measurement height and the linear motor 50 adjusting the bridging structure 4 in the X-axis direction.

  When the movement of the gap sensor 42 to the measurement start position is completed, the linear motor 50 moves the bridging structure 4 in the (+ X) direction. Thus, the gap sensor 42 measures the gap between the surface of the substrate 90 and the slit nozzle 41 in the coating region on the surface of the substrate 90 while maintaining a predetermined measurement height (step S12). The application region is a region on the surface of the substrate 90 where the resist solution is to be applied, and is usually a region obtained by removing a region having a predetermined width along the edge from the entire area of the substrate 90. . In addition, in the substrate processing apparatus 1, the slit nozzle 41 and the holding surface at the measurement altitude are prevented so that the slit nozzle 41 does not come into contact with an object such as the substrate 90 or a foreign object during the measurement by the gap sensor 42. The distance in the Z-axis direction with respect to 30 is sufficiently secured.

  The measurement result of the gap sensor 42 is transmitted to the control unit 7. The control unit 7 stores the transmitted measurement result of the gap sensor 42 in the storage unit in association with the horizontal position (position in the X-axis direction) detected by the linear encoder 51.

  When scanning (measurement) by the gap sensor 42 is completed, the linear motor 50 moves the bridging structure 4 in the X-axis direction and moves the detection unit 45 to the end position of the substrate 90 (step S13). The end position refers to the optical axis of the sensor (detection sensor 450 in the present embodiment) that is closest to the (−X) side of the detection unit 45, approximately on the (+ X) side of the substrate 90. It is a position along. Further, when it is determined by the measurement by the gap sensor 42 that the thickness of the substrate 90 is not within the specified range, the substrate processing apparatus 1 displays an alarm on the display unit and moves the slit nozzle 41 to the standby position. At the same time, the substrate 90 in which an abnormality is detected is discharged.

  When the detection unit 45 moves to the end position, the control unit 7 stops the bridging structure 4 by stopping the linear motor 50. Further, based on the measurement result from the gap sensor 42, the posture of the slit nozzle 41 in the YZ plane is an appropriate posture (the interval between the slit nozzle 41 and the application region is an appropriate interval for applying the resist (this embodiment In the embodiment, the position of the nozzle support portion 40 is calculated, and the lift mechanism 43, 44 is controlled based on the calculation result to calculate the slit. The nozzle 41 is adjusted to an appropriate posture.

  Since the detection unit 45 of the substrate processing apparatus 1 is disposed on the (−X) side of the slit nozzle 41, the slit nozzle 41 is not opposed to the substrate 90 when the detection unit 45 is in the end position. Has moved. Therefore, even if the slit nozzle 41 is moved in the (−Z) direction and adjusted to an appropriate posture while the detection unit 45 is in the end position, there is almost no risk that the slit nozzle 41 comes into contact with the object.

  When the posture adjustment of the slit nozzle 41 is completed, the control unit 7 starts detection of the object by the detection unit 45 (step S14). Further, the linear motor 50 is driven to move the bridging structure 4 in the (−X) direction (step S21), and based on the output from the detection unit 45, it is determined whether or not an object has been detected (step). S22). If it is determined that any of the detection sensors 450 and 451 and the auxiliary detection sensor 452 has detected the object, the process from step S27 is performed to prevent the slit nozzle 41 from contacting the object. It will be described later.

  On the other hand, if the target is not detected, the control unit 7 confirms the position of the slit nozzle 41 based on the output of the linear encoder 51, and continues to steps S21 to S23 until the slit nozzle 41 moves to the discharge start position. The process is repeated (step S23). The discharge start position is a position where the slit nozzle 41 substantially follows the (+ X) side of the application region.

  When the slit nozzle 41 moves to the discharge start position, a resist solution is sent to the slit nozzle 41 by a resist pump (not shown), and the slit nozzle 41 discharges the resist solution to the application region. Along with the discharging operation, the linear motor 50 moves the slit nozzle 41 in the (−X) direction (step S24). Thereby, the application region of the substrate 90 is scanned by the slit nozzle 41, and the resist solution is applied. In parallel with the moving operation in step S24, the control unit 7 determines whether or not an object has been detected as in step S22 (step S25).

  If it is determined in step S25 that the control unit 7 has detected the object (Yes in step S25), the control unit 7 stops the linear motor 50, thereby moving the slit nozzle 41 in the (−X) direction. The operation is stopped and an alarm is output to the display unit (step S27). Note that step S27 is executed in substantially the same manner when the control unit 7 determines in step S22 that the object has been detected.

  As described above, in the substrate processing apparatus 1, when the object is detected by the detection unit 45 while the slit nozzle 41 is moving (scanning), the slit nozzle 41 is immediately stopped to move, thereby the slit nozzle 41. And contact with the object can be prevented. Therefore, it is possible to effectively prevent the slit nozzle 41 and the substrate 90 from being damaged by contact.

  Moreover, since an abnormality can be notified to the operator by outputting an alarm, recovery work and the like can be performed efficiently. Note that any method may be used for the alarm as long as it allows the operator to know the occurrence of an abnormal situation, and an alarm sound may be output from a speaker or the like.

  After execution of step S27, the resist pump is stopped to stop the discharge of the resist solution, and the slit nozzle 41 is retracted to the standby position by the linear motor 50 and the lifting mechanisms 43 and 44 (step S28). Further, the substrate 90 is unloaded from the substrate processing apparatus 1 (step S29). When an object is detected in step S22, since the resist solution ejection has not yet started, the process for stopping the resist solution ejection is not performed. Further, the substrate 90 to be unloaded as a result of the execution of step S27 is distinguished from other substrates 90 and is transported to the reprocessing step by the operator or the transport mechanism. Further, as shown in FIGS. 4 and 5, it is conceivable that the foreign matter NG is attached to the stage 3. Therefore, when step S <b> 27 is performed, it is preferable to clean the stage 3.

  On the other hand, when the object is not detected in step S25 (No in step S25), the control unit 7 confirms the position of the slit nozzle 41 based on the output of the linear encoder 51, and the slit nozzle 41 is at the discharge end position. Steps S24 to S26 are repeated until it moves to (Step S26). As described above, when the object does not exist, scanning by the slit nozzle 41 is performed on the entire coating region, and a layer of the resist solution is formed on the surface of the substrate 90 in the entire coating region.

  When the slit nozzle 41 moves to the discharge end position, the controller 7 stops the resist pump to stop the discharge of the resist solution, and the linear motor 50 and the lifting mechanisms 43 and 44 retract the slit nozzle 41 to the standby position. (Step S28). In parallel with this operation, the control unit 7 stops the detection of the object by the detection unit 45.

  Further, the stage 3 stops the suction of the substrate 90, the operator or the transport mechanism picks up the substrate 90 from the holding surface 30, and carries the substrate 90 to the next processing step (step S29).

  Note that when the coating process is completed, a resist film thickness inspection process may be performed. That is, the elevating mechanisms 43 and 44 move the gap sensor 42 to the measurement altitude by moving the nozzle support 40 in the (+ Z) direction. Further, when the linear motor 50 moves the bridging structure 4 in the (+ X) direction, the gap sensor 42 scans the coating region, measures the gap with the resist film formed on the substrate 90, and transmits it to the control unit 7. To do. The controller 7 compares the gap value (distance to the surface of the substrate 90) measured before applying the resist solution and the gap value (distance to the surface of the resist film) measured after applying the resist. Thus, the thickness of the resist film on the substrate 90 is calculated, and the calculation result is displayed on the display unit or the like.

  When the substrate 90 carry-out processing (step S29) is completed, if processing is continuously performed on a plurality of substrates 90, the processing returns to step S11 and is repeatedly executed, and there is no substrate 90 to be processed. If so, the process ends (step S30).

  As described above, the substrate processing apparatus 1 according to the present embodiment is disposed at a position deviating from the position where the direct light of the laser beams irradiated by the light projecting units 450a and 451a is received. Light receiving units 450b and 451b that receive, as detection light, laser light reflected by the object among the laser light emitted by 451a is provided, and the object is detected when the light receiving units 450b and 451b receive the detection light. By doing so, the positions of the light receiving portions 450b and 451b may be relatively ambiguous, and the burden of adjustment work is reduced. In addition, since the object can be detected if the light receiving portions 450b and 451b receive the detection light even slightly, the influence of the width of the substrate 90 can be suppressed, and the accuracy is improved.

  Further, the light receiving portions 450b and 451b are arranged at positions shifted in a direction substantially perpendicular to the scanning direction of the slit nozzle 41 from the position where the direct light of the laser beam is received, thereby causing vibration caused by scanning by the slit nozzle. The influence of can be suppressed. Accordingly, erroneous detection can be suppressed, and an accurate detection result can be obtained.

  In addition, an auxiliary detection sensor 452 that detects an object that may interfere with the slit nozzle 41 during scanning of the slit nozzle 41 is provided, and the light receiving unit 452b of the auxiliary detection sensor 452 is located at a position facing the light projecting unit 452a. By receiving the direct light of the laser light that is arranged and emitted from the light projecting unit 452a, and the amount of direct light received by the light receiving unit 452b is equal to or less than a predetermined threshold, The range of detectable objects is expanded.

  In addition, the light projecting unit 450a of the detection sensor 450 and the light projecting unit 451a of the detection sensor 451 are separately arranged on both sides of the substrate 90 held on the stage 3, thereby being affected by the width of the substrate. The object can be detected without any problem.

  In addition, since the detection unit 45 is attached to the moving mechanism 5, even when the slit nozzle 41 is replaced, it is not necessary to adjust the position of the detection unit 45 again, and the work efficiency can be improved. it can.

<2. Second Embodiment>
In the first embodiment, the detection unit 45 is configured to be attached to the moving mechanism 5. However, the attachment position of the detection unit 45 is not limited to this, and any position that can detect an object is used. It can be installed anywhere.

  FIG. 11 is an enlarged view of the periphery of the detection unit 45 of the substrate processing apparatus 1a according to the second embodiment configured based on such a principle. As shown in FIG. 11, the substrate processing apparatus 1 a has a detection unit 45 attached to a nozzle support unit 40. The slit nozzle 41 is fixed to the nozzle support 40 as in the above embodiment, and the slit nozzle 41 moves integrally with the nozzle support 40. A slit nozzle 41 is fixed to the nozzle support portion 40. Therefore, the detection unit 45 moves integrally while maintaining a relative distance from the slit nozzle 41.

  The substrate processing apparatus 1a has substantially the same configuration as the substrate processing apparatus 1 in the first embodiment, except that the detection unit 45 is attached to the nozzle support unit 40. The operation of the substrate processing apparatus 1a is also substantially the same as that of the substrate processing apparatus 1. However, in the substrate processing apparatus 1, the position adjustment operation of the detection sensors 450 and 451 and the auxiliary detection sensor 452 in the Z-axis direction is performed based on the position of the holding surface 30 of the stage 3. In the substrate processing apparatus 1 a, however, the slit nozzle The position adjustment work in the Z-axis direction is performed with reference to the end portion on the (−Z) side of 41.

  As described above, even when the detection unit 45 is attached to the nozzle support unit 40 as in the substrate processing apparatus 1a in the second embodiment, it is almost the same as the substrate processing apparatus 1 in the first embodiment. Similar effects can be obtained.

  In addition, since the detection sensors 450 and 451 and the auxiliary detection sensor 452 are attached so as to move integrally while maintaining a relative distance from the slit nozzle 41, the detection unit 45 and the slit nozzle 41 are temporarily arranged. After the relative distance is adjusted, the relative distance is constant regardless of the posture of the slit nozzle 41 (mainly the position in the Z-axis direction), so that the detection accuracy can be improved. Further, in the substrate processing apparatus 1a, even if the thickness of the substrate 90 to be processed is changed, it is not necessary to perform the position adjustment operation again, and the work efficiency can be improved.

<3. Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made.

  For example, in the substrate processing apparatus 1a in the second embodiment, the detection unit 45 is described as being attached to the nozzle support unit 40. However, for example, the detection unit 45 may be directly attached to the slit nozzle 41.

  In the above embodiment, the auxiliary detection sensor 452 includes the light projecting unit 452a and the light receiving unit 452b. However, the auxiliary detection sensor 452 can be realized even with a configuration including only the light receiving unit 452b. FIG. 16 is a diagram showing a detection sensor 450 and an auxiliary detection sensor 452 in a modified example configured based on such a principle. As shown in FIG. 16, the light receiving portion 452 b of the auxiliary detection sensor 452 is disposed at a position facing the light projecting portion 450 a of the detection sensor 450. That is, the positions of the light projecting unit 450a and the light receiving unit 452b are arranged so that the positions in the X-axis direction and the Z-axis direction are substantially equal. With this arrangement, the light receiving unit 452b receives the direct light of the laser light emitted from the light projecting unit 450a. Also with this configuration, the auxiliary detection sensor 452 can obtain the same effects as those of the above embodiment. Further, since the auxiliary detection sensor 452 also serves as the light projecting unit 450a of the detection sensor 450, the apparatus configuration can be simplified. The light projecting unit used by the auxiliary detection sensor 452 is not limited to the light projecting unit 450a, and may be the light projecting unit 451a.

It is a front view of the substrate processing apparatus in the 1st Embodiment of this invention. It is an enlarged view of the peripheral part of the detection part in a substrate processing apparatus. It is a top view which shows the scanning range of a slit nozzle, and the arrangement | positioning relationship of a detection sensor. It is a right view which shows the arrangement | positioning relationship between a slit nozzle and a detection sensor. It is a left view which shows the arrangement | positioning relationship between a slit nozzle and a detection sensor. It is a figure which shows the locus | trajectory of a laser beam when a target object does not exist in the case of the detection by a detection sensor. It is a figure which shows the locus | trajectory of a laser beam when a target object exists in the case of the detection by a detection sensor. It is a figure explaining the case where a detection sensor detects the target object of the position near a light-receiving part. It is a flowchart which shows operation | movement of a substrate processing apparatus. It is a flowchart which shows operation | movement of a substrate processing apparatus. It is an enlarged view in the peripheral part of the detection sensor of the substrate processing apparatus in 2nd Embodiment. It is a conceptual diagram for demonstrating the principle in which the transmissive | pervious laser sensor used for the conventional coating device detects an interference object. It is a conceptual diagram for demonstrating the principle in which the transmissive | pervious laser sensor used for the conventional coating device detects an interference object. It is a conceptual diagram for demonstrating the principle in which the transmissive | pervious laser sensor used for the conventional coating device detects an interference object. It is a conceptual diagram for demonstrating the principle in which the transmissive | pervious laser sensor used for the conventional coating device detects an interference object. It is a figure which shows the detection sensor and auxiliary detection sensor in a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a Substrate processing apparatus 3 Stage 30 Holding surface 41 Slit nozzle 43, 44 Elevating mechanism 45 Detection part 450,451 Detection sensor 450a, 451a Light projection part 450b, 451b Light reception part 452 Auxiliary detection sensor 452a Light projection part (auxiliary light projection part) Part)
452b Light receiving part (auxiliary light receiving part)
5 Moving mechanism 50 Linear motor 7 Control unit 90 Substrate DRL Direct light E0 Scanning range LFL Reflected light NG Foreign matter

Claims (4)

A substrate processing apparatus for applying a predetermined processing liquid to a substrate,
Holding means for holding the substrate;
Discharge means for discharging a predetermined processing liquid to the substrate held by the holding means;
Moving means for relatively moving the substrate held by the holding means and the discharge means, and executing scanning by the discharge means with respect to the substrate;
At least one detection means for detecting an object that may interfere with the ejection means during scanning of the ejection means;
Control means for controlling the moving means based on a detection result by the detecting means;
With
The detection means is
A light projecting unit that irradiates the surface of the substrate held by the holding unit in parallel with a laser beam;
Laser light that is arranged at a position that deviates upward from a position that receives direct light of the laser light emitted by the light projecting unit, and that is reflected by the object among the laser light emitted by the light projecting unit A light receiving portion that receives light as detection light,
With
The substrate processing apparatus, wherein the detection unit transmits a detection result indicating that the object is detected when the light receiving unit receives the detection light to the control unit. The substrate processing apparatus according to claim 1,
The substrate processing apparatus, wherein the light receiving unit is disposed at a position displaced in a direction substantially perpendicular to a scanning direction of the ejection unit. The substrate processing apparatus according to claim 1, wherein:
An auxiliary detection means for detecting an object that may interfere with the discharge means during scanning of the discharge means;
The auxiliary detection means is
An auxiliary light receiving unit that is disposed at a position facing the light projecting unit or the auxiliary light projecting unit, and that receives the direct light of the laser light emitted from the light projecting unit or the auxiliary light projecting unit;
With
The auxiliary detection means transmits a detection result indicating that the object has been detected to the control means when the received light amount of the direct light in the auxiliary light receiving unit is a predetermined threshold value or less,
The substrate processing apparatus, wherein the control unit controls the moving unit according to a detection result of the detection unit and a detection result of the auxiliary detection unit. A substrate processing apparatus according to any one of claims 1 to 3 ,
Two or more of the at least one detection means,
The substrate processing apparatus, wherein the light projecting unit of one detection unit and the light projection unit of another detection unit are separately arranged on both sides of the substrate held by the holding unit.

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