JP2007142292A - Substrate inspection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate inspection apparatus capable of keeping the position of a surface to be inspected more highly accurately. <P>SOLUTION: The substrate inspection apparatus for inspecting a substrate 101 is provided with an XY-stage 121 moving in a horizontal direction; a Z-stage 103 arranged on the XY-stage 121 and moving in a vertical direction; three actuator mechanisms 107a, 107b and 107c each having a piezoelectric element and causing the Z-stage 103 to move in a vertical direction at three points; and an elastic hinge 108 for supporting the Z-stage 103. Further, a θ-stage 106 moving in a rotating direction using the center of a substrate 101 as a virtual center axis is arranged on the Z-stage 103. The θ-stage 106 is provided with a rod 308 moving in a linear direction and an elastic member 113 connected to the rod 308 and rotating the θ-stage 106 while elastically deforming. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a substrate inspection apparatus, for example, a pattern inspection technique for inspecting a pattern defect of an object to be a sample used for semiconductor manufacture, a photomask used when manufacturing a semiconductor element or a liquid crystal display (LCD), The present invention relates to an apparatus for inspecting a defect of an extremely small pattern such as a wafer or a liquid crystal substrate.

  In recent years, the circuit line width required for a semiconductor element has been increasingly narrowed as a large scale integrated circuit (LSI) is highly integrated and has a large capacity. These semiconductor elements use an original pattern pattern (also referred to as a mask or a reticle, hereinafter referred to as a mask) on which a circuit pattern is formed, and the pattern is exposed and transferred onto a wafer by a reduction projection exposure apparatus called a stepper. It is manufactured by forming a circuit. Therefore, a pattern drawing apparatus capable of drawing a fine circuit pattern is used for manufacturing a mask for transferring such a fine circuit pattern onto a wafer. A pattern circuit may be directly drawn on a wafer using such a pattern drawing apparatus.

  Here, it is known that various defects occur in the wafer and mask patterns created by the pattern drawing apparatus as described above during the production process. Such defects not only make the manufactured semiconductor device impossible to operate, but also greatly affect the manufacturing yield. Therefore, in order to prevent defects in the final product from occurring, an inspection / correction process in which defects are detected and corrected and remanufactured in the manufacturing process is an important technique in semiconductor manufacturing.

  On the other hand, with the development of multimedia, LCDs (Liquid Crystal Display) are increasing in size of the liquid crystal substrate to 500 mm × 600 mm or more, and TFTs (Thin Film Transistors) formed on the liquid crystal substrate. : Thin film transistors) and the like are being miniaturized. Therefore, it is required to inspect a very small pattern defect over a wide range. For this reason, there is an urgent need to develop a substrate inspection apparatus that efficiently inspects defects of a photomask used in manufacturing such a large area LCD pattern and a large area LCD in a short time.

Therefore, development of a substrate inspection apparatus that inspects and detects defects generated on a substrate such as a wafer or a mask has been attempted. In a substrate inspection apparatus, generally, on a XY stage, a substrate held by a holder is continuously moved or stepped at a predetermined speed in the XY direction, and an optical image is obtained by an optical system using a laser light source while repeating such movement. obtain. And the presence or absence of the defect which arose on the board | substrate is test | inspected, processing this optical image.
For example, as a pattern inspection method, “die to die inspection” for comparing optical image data obtained by imaging the same pattern at different locations on the same mask, CAD data or CAD as design data used when drawing a mask pattern There is “die to database inspection” in which design image data is generated based on drawing data obtained by converting data into a device input format, and is compared with optical image data serving as measurement data obtained by imaging a pattern. In the inspection method in such an inspection apparatus, the sample is placed on the XY stage, and the light beam scans on the sample as the XY stage moves to perform the inspection. The sample is irradiated with a light beam by a light source and an illumination optical system. The light transmitted or reflected through the sample is imaged on the sensor via the optical system. The image picked up by the sensor is sent to the comparison circuit as measurement data. The comparison circuit compares the measured data and the reference data according to an appropriate algorithm after the images are aligned, and determines that there is a pattern defect if they do not match.

Here, in the table apparatus including the above-described XY stage, a technique for displacing each of two opposing positions in the optical axis direction by a piezoelectric element is disclosed in the literature (for example, see Patent Document 1).
JP-A-6-123787

  Here, when considering the stage mechanism of the substrate inspection apparatus, when performing defect inspection of the substrate, the positional change (focal length) in the vertical direction (z direction) of the inspection surface of the substrate that irradiates the light of the optical system is large. In some cases, inspection cannot be performed because the depth of focus of the auto-focus lens of the optical system is small. Therefore, for movement in the Z direction, it is necessary to provide a mechanism capable of fine movement. For example, it is conceivable that the Z moving mechanism is driven by a centering disk using a servo motor as a power source. However, although it seems that the stroke can be as small as several tens of μm, the stroke mechanism is a centering disk, so it can only be controlled along the path of the centering disk, and linear drive that matches the situation is possible. There was a problem that it was difficult to control because it was not possible.

  Furthermore, as a factor that affects the change in the position of the inspection surface of the substrate, if the running accuracy of the XY stage, that is, the vertical movement (including pitching) is large, the substrate also moves while changing in the same way. The problem that it will shift | deviate arises. Such a complex cause affects the analysis degree of the inspection image and makes it difficult to perform a high-accuracy inspection.

  And even if a piezoelectric element is used as a mechanism that can be finely moved in the Z direction as in the technique described in Patent Document 1, driving the positions of two opposing points with a piezoelectric element causes various problems as described above. It is difficult to maintain the plane accuracy of the inspection surface of the substrate that changes every moment depending on the factor.

  An object of the present invention is to provide a substrate inspection apparatus that overcomes such problems and maintains the position of the inspection surface with higher accuracy.

The substrate inspection apparatus according to one aspect of the present invention includes:
In a substrate inspection apparatus for inspecting a substrate to be inspected,
An xy stage that moves horizontally;
A Z stage disposed on the XY stage and moving in the vertical direction;
Three piezoelectric elements that move the Z stage up and down at three locations;
It is provided with.

  According to the present invention, the height and angle of the inspection surface can be controlled with high accuracy while finely moving the substrate to be inspected in the Z direction. Therefore, the substrate to be inspected can be kept at the position of the inspection surface with higher accuracy.

Embodiment 1 FIG.
FIG. 1 is a conceptual diagram showing the configuration of the substrate inspection apparatus according to the first embodiment.
In FIG. 1, a surface plate 120 serving as a reference base is attached via a vibration isolation table 119 from the installation floor. On the surface plate 120, an optical system 118 such as a laser light source 117, reflection mirrors 211, 212, 213, and a light receiver 214 is disposed. On the surface plate 120, an XY stage 121 and a Z / θ stage 122 are mounted on the XY stage 121. Here, on the Z · θ stage 122, a holder 102, which is an example of a holding unit that holds and arranges the substrate 101 to be inspected, is mounted. The substrate 101 is conveyed by a loader (not shown), and is chucked by a chucking mechanism of a robot hand 123 that is separately (or connected) to the surface plate 120 at a predetermined delivery position. The holder 102 is mounted and disposed at a predetermined position. In other words, the substrate 101 is transported onto the Z / θ stage 122 by a combination of a transport mechanism, a robot hand 123, and the like, and the robot hand 123 is a predetermined position in the central portion that is the holding position of the holder 102 in the substrate inspection apparatus 100. Is placed on board. In addition, an opening having an opening surface larger than the width of the substrate 101 is formed on the plane of the holder 102. The opening of the holder 102 is provided so that the laser beam of the optical system for inspection can be transmitted and interference of the chuck mechanism operation when the substrate 101 of the robot hand 123 is mounted can be avoided.
Here, it is desirable that the substrate inspection apparatus 100 and the substrate inspection system are installed in a clean room chamber and used in an environment in which cleanliness and temperature are strictly controlled.

Hereinafter, the operation of the substrate inspection apparatus will be described.
Laser light emitted from a laser light source 117 while the XY stage 121 repeats continuous movement or step movement of the substrate 101 held by the holder 102 on the Z / θ stage 122 in the XY direction which is the horizontal direction at a predetermined speed. Is reflected by the reflection mirrors 211 and 212, passes through the pattern image serving as the inspection position of the substrate 101, is reflected by the reflection mirror 213, and is received by the light receiver 214. An optical image can be obtained by the optical system 118. And the presence or absence of the defect which arose in the board | substrate 101 is test | inspected by processing this optical image with the image processing apparatus which is not shown in figure.

FIG. 2 is a plan view showing an example of the configuration of the Z · θ stage in the first embodiment.
FIG. 3 is a view showing a part of the X arrow view of FIG.
FIG. 4 is a diagram showing a part of the view in the direction of arrow Y in FIG.
FIG. 5 is a diagram showing a part of the Z arrow view of FIG.
However, the scales and the like are not matched in each drawing.
The Z / θ stage 122 described above has a Z stage 103 and a θ stage 106. In FIG. 2, a Z stage 103 that moves in the vertical direction (also referred to as the Z direction or the optical axis direction) is disposed on the XY stage 121. The XY stage 121 and the Z stage 103 are connected by three actuator mechanisms 107 (a, b, c) each mounted with three piezoelectric elements (an example of a piezoelectric element) distributed at substantially equal angles. The stage 103 is moved up and down at three locations. The three actuator mechanisms 107 are configured to be able to load the entire mass of the Z · θ stage 122 and are individually provided with height adjustment mechanisms. Since the actuator mechanism 107 uses a piezo, the Z stage 103 can be finely moved in the Z direction. Further, unlike the eccentric disk, it can be linearly driven. Furthermore, since the Z stage 103 is driven at three points, the tilt control of the surface can be facilitated, and the flatness of the substrate 101 can be maintained with high accuracy. Further, when the Z stage 103 is driven at two points, it is difficult to control the tilt of the surface, and when the Z stage 103 is driven at four points or more, at least two actuator mechanisms 107 are driven. Otherwise, it becomes difficult to control the surface, but by driving the Z stage 103 at three points as in the first embodiment, not only the surface tilt control but also the adjustment at one point depending on the angle of the surface is possible. it can. Control can be facilitated by adjusting at one point.

  A tension spring 310 shown in FIG. 3 is connected to the XY stage 121 and the Z stage 103 via a fixing member, and pressurizes the Z stage 103 toward the XY stage 121 side. By applying pressure, the Z stage 103 is prevented from being lifted. The tension spring 310 has a structure capable of adjusting the spring force. As a result, the operation of the actuator mechanism 107 can be accurately transmitted to the Z stage 103. Further, by constituting the tension spring 310, it is possible to apply pressure to the Z stage 103 by a simple method without taking up space. Here, by disposing the tension springs 310 on both sides of the actuator mechanism 107a, it is possible to apply pressure with equal force from both sides. Further, as shown in FIG. 2, the actuator mechanism 107b and the actuator mechanism 107c arranged on the side opposite to the side on which the actuator mechanism 107a is arranged can be arranged on the side surface of the same Z stage 103. By arranging one tension spring 310 in the vicinity of each of 107b and actuator mechanism 107c, each tension spring 310 can apply pressure with an equal force. As described above, the tension springs 310 are arranged at both ends or near one side of the actuator mechanism 107 to suppress the Z / θ stage 122 from rising.

  Further, in order to measure the amount of movement of the Z stage 103 due to the movement of each actuator mechanism 107 by the three piezo elements and manage the distance, each example of three displacement meters near each of the three actuator mechanisms 107 A micro sense (capacitive displacement meter) 109 is disposed.

  Further, the support in the X, Y, and θ directions is connected to the XY stage 121 and the Z stage 103 via three elastic hinges 108, and the XY stage 121 and the Z stage 103 are connected. The three elastic hinges 108 can support the Z stage 103 while elastically deforming in accordance with the movement of each actuator mechanism 107.

  On the Z stage 103, a θ stage 106 that moves in the rotation direction with the center of the substrate 101 as the virtual center axis is disposed. The θ stage 106 has a frame shape (also referred to as a frame shape), and four bearings are arranged concentrically on the outer periphery. Two adjacent bearings of the four bearings are fixed-type bearings 110, and the other two arranged at positions facing the two fixed-type bearings 110 are used for adjusting the clearance in the direction of the rotation axis. The adjustment type bearing 111 having an adjustment mechanism is preferable. By using the adjustment type bearing 111, the rotation axis can be aligned.

On the Z stage 103, a θ driving linear actuator 112, which is an example of a linear driving unit having a rod 308 that moves in the linear direction on the XY plane, is arranged outside the θ stage 106. As the θ drive linear actuator 112, it is preferable to use an encoder built-in type that allows easy position control.
The rod 308 is connected to an elastic member 113 that rotates the θ stage 106 in accordance with the movement accompanying the movement of the rod 308 while elastically deforming. The elastic member 113 is connected to the θ stage 106 via the attachment member 302 and the attachment member 304. By using the elastic member 113, the linear movement of the rod 308 can be converted into the rotational direction in which the θ stage 106 moves. In other words, the offset amount caused by the rotation of the θ stage 106 can be absorbed by the deformation of the θ elastic structural member 113.
As the elastic member 113, for example, it is preferable to use a thin rod-shaped wire (wire) of about φ1 to 2 mm. For example, it is preferable to use a stainless steel wire. By using a wire having a circular cross section, it can be deformed with the same force in the vertical and horizontal directions. Therefore, the θ stage 106 can be smoothly rotated. Further, the θ driving linear actuator 112 moves the rod 308 by, for example, a screw mechanism. A pressure is applied between the attachment member 304 and the Z stage 103 in the moving direction of the rod 308 by the tension spring 306 with respect to the θ stage 106. By applying the pressure, it is possible to prevent backlash due to backlash in the moving direction generated by the screw mechanism of the θ actuator linear actuator 112. Further, the movement amount limiter may be controlled by attaching a photo sensor (not shown) to the θ linear actuator 112 inside or outside, and controlling the origin by using the photo sensor.

  Further, on the Z stage 103, a hole h serving as an opening for floating the θ stage 106 using a gas (for example, air) is formed. In FIG. 2, it is formed at four locations and is connected to the outside from the side surface of the Z stage 103. Air is supplied to the hole h from the connection port 312 shown in FIG. Further, a θ vacuum chuck groove 114 serving as an opening for vacuum chucking the θ stage 106 is formed on the Z stage 103. In FIG. 2, it is formed at four locations and is connected to the outside from the side surface of the Z stage 103. Vacuum is drawn from the connection port 314 shown in FIGS. 4 and 5 continuing from the θ vacuum chuck groove 114.

  As a driving method of the θ stage 106, at the time of inspection, the inspection is performed in a state where the lower surface of the θ stage 106 is attracted (vacuum chuck) to the upper surface of the Z stage 103 by the θ vacuum chuck groove 114 provided on the upper surface of the Z stage 103. When aligning the rotation direction of the substrate 101, air is blown out from the hole h provided on the upper surface of the Z stage 103 toward the lower surface of the θ stage 106, and the θ stage 106 is floated from the upper surface of the Z stage 103 at several tens of μm or less. In this state, the θ driving linear actuator 112 is driven, and rotational alignment is performed while checking by image processing of the optical system.

  Here, depending on the positioning accuracy of the substrate 101 and the running accuracy of the XY stage 121 in the inspection direction when the substrate 101 is mounted on the holder 102, it is necessary to consider an element of tilt accuracy (yawing). However, if an image is captured with a wide range of image capture overlaps in consideration of such an inclination accuracy factor, there is a problem that it takes a very long inspection time and is inefficient. Therefore, the tilt accuracy can be improved by providing the θ stage 106 as in the first embodiment. Therefore, the overlapping width of image capture can be reduced. As a result, the inspection time can be shortened.

  A holder 102 that holds the substrate 101 is disposed on the θ stage 106. The substrate 101 is held by the holder 102. On the θ stage 106, a linear light regressive laser sensor using a combination of the light emitting unit 115 and the reflecting mirror 116 is provided to determine whether or not the substrate 101 is mounted on the holder 102. The presence or absence of the substrate 101 is determined depending on whether the laser beam 141 returns to the light emitting unit 115 after being reflected by the reflecting mirror 116 or is diffusely reflected in the middle due to the relationship of the refractive index when passing through the substrate 101. Is possible. Here, the light emitting unit 115 and the reflection mirror 116 are arranged so that the laser light 141 emitted from the light emitting unit 115 is emitted from the horizontal direction in the vicinity of the middle of the side surface of the substrate 101. The light path in the substrate 101 can be lengthened by transmitting the opposite side surface from the side surface of the substrate 101. Further, the light emitting unit 115 and the reflection mirror 116 are arranged so as to pass through at an angle with respect to the direction orthogonal to the side surface of the substrate 101 while being in the horizontal direction. In other words, the linear light regression type laser sensor measures the presence or absence of the substrate 101 by irradiating the side surface of the substrate 101 with the laser beam 141 obliquely in the horizontal direction. Thereby, the optical path in the substrate 101 can be further lengthened. By lengthening the optical path in the substrate 101, the refractive index of the laser light 141 can be increased, and erroneous detection that is not arranged even though the substrate 101 is arranged on the holder 102 can be reduced.

A holder 102 that holds the substrate 101 is disposed and mounted at the center of the θ stage 106. The holder 102 can be positioned by a plurality of pins 142 provided on the θ stage 106. The holder 102 is detachably disposed during the maintenance of the optical system. Further, the holder 102 is provided with a reflection light amount sensor 143 and a transmission light amount sensor 144 which are examples of the light amount measurement unit. By arranging the holder 102 close to the substrate, it is possible to measure the amount of inspection light more accurately.
In the first embodiment, the substrate inspection apparatus 100 describes a case where inspection is performed by transmitting inspection light to the substrate 101. However, the inspection is performed by reflecting inspection light on the inspection surface of the substrate 101. Also good. Here, it is preferable to arrange the reflection light amount sensor 143 and the transmission light amount sensor 144 so that the substrate inspection apparatus 100 can be used as the transmission type or the reflection type. When inspecting as a transmission type, the transmission light amount sensor 144 measures the amount of inspection light when the inspection light is irradiated onto the substrate 101 from above the inspection surface of the substrate 101. When inspecting as a reflection type, the reflection light amount sensor 143 measures the amount of inspection light when the substrate 101 is irradiated with inspection light from below the inspection surface of the substrate 101. By arranging them upside down, they can be used as a transmission type or a reflection type.

  In addition, a temperature sensor 145 is disposed on the holder 102 in a non-contact manner with the substrate 101. By arranging the holder 102 close to the substrate 101, a more accurate temperature can be measured. Further, by making no contact with the substrate 101, it is possible to prevent the substrate inspection apparatus 100 from erroneously detecting the image of the temperature sensor 145. Further, the substrate 101 can be prevented from being damaged, such as when the substrate 101 is transported.

  Further, on the Z stage 103, a square bar-shaped reflecting mirror for laser length measurement for measuring the position in the X direction and the Y direction using laser light in order to measure the image processing position data of the substrate 101. 104 and a reflection mirror 105 are provided in the X direction and the Y direction. The reflecting mirror 104 and the reflecting mirror 105 are fixed with an elastic structure (not shown) to support a necessary direction, so that the mirror does not bend so that the XY stage 121 operates and does not move even when acceleration is applied. It is preferable to be fixed to. Since the reflecting mirror 104 and the reflecting mirror 105 are arranged on the Z stage 103 and are closer to the substrate position as compared with the case of being arranged on the XY stage 121, the height of the surface of the substrate 101 and the height of the reflecting position for laser length measurement Can be easily combined. Furthermore, by disposing on the Z stage 103, it is possible to prevent the angle change of the reflecting mirror caused by the rotation of the θ stage 106 when it is disposed on the θ stage 106. The laser measuring reflection mirror 104 and the reflection mirror 105 arranged on the Z stage 103 constantly grasp the position of the substrate 101 in the X and Y directions and process the data.

FIG. 6 is a diagram showing a part of the view taken along the arrow A in FIG.
FIG. 7 is a diagram illustrating a part of the C arrow view of FIG. 2.
6 and 7 show examples of detailed cross sections of four bearings arranged on the outer periphery of the θ stage.
FIG. 6 shows a configuration of the fixed bearing 110 that is arranged on the outer periphery of the concentric circle of the θ stage 106. The fixed bearing 110 is a rotation guide bearing, and the shaft 316 of the fixed bearing 110 is fixed to the Z stage 103 side. The outer ring 318 of the fixed bearing 110 is in contact with the outer circumference of the θ stage 106 without any gap. However, when the θ stage 106 floats several tens of μm, it has a bearing structure that can move in the vertical direction, so that it slides so as not to be a vertical load on the θ stage 106.
In FIG. 7, a configuration of the adjustable type bearings 111 arranged on the outer periphery of the concentric circle of the θ stage 106 is shown. The adjustment type bearing 111 is also a rotation guide bearing, and is configured to be adjustable in the direction of the rotation center of the θ stage 106. A shaft base 146 of the adjustment type bearing 111 is formed integrally with the shaft and is fixed to the Z stage 103 side. A pressing adjustment screw 147 capable of pressing the shaft base 146 from the rear is disposed. After a certain pressure is applied to the bearing by the pressing adjustment screw 147, the shaft base 146 is fixed to the Z stage 103 side. Thereby, the play in the outer peripheral direction of the θ stage 106 can be removed. The outer ring 320 of the adjustable bearing 111 may be the same as that shown in FIG.

FIG. 8 is a view showing a part of the B arrow view of FIG.
In FIG. 8, the detailed cross section of the linear light regression type laser sensor arrange | positioned on the (theta) stage is shown. As described above, a linear light regression laser sensor is provided to determine whether or not the substrate 101 is mounted on the holder 102. The laser light 141 is emitted from the light emitting unit 115, passes through the vicinity of about the middle of the thickness of the substrate 101, and then strikes the reflection mirror 116 provided on the opposite side of the light emitting unit 115 to return to the light emitting unit 115. It is a sensor of the coming type. As a normal usage, when the optical axis is aligned without the substrate 101 and the substrate 101 is placed, the laser light 141 does not return to the light emitting unit 115 due to the refractive index when passing through the substrate 101. The presence or absence of the substrate 101 can be determined. Here, in order to match the height of the substrate 101, a hole for an optical path is formed so as to penetrate the holder 102.

As described above, in order to manage the movement distance of the actuator mechanism 107, the micro sense (capacitive displacement meter) 109 is disposed in the vicinity of each actuator mechanism 107. Since the micro-sense 109 needs an initial gap adjustment of several tens of μm from the measurement object, the micro-sense 109 includes a gap adjustment mechanism such as a taper slide type or a screw adjustment type.
FIG. 9 is a detailed view of the W portion of FIG.
FIG. 10 is a detailed view of a portion V in FIG.
9 and 10 are detailed views of a microsense (capacitance displacement meter) 109 disposed in the vicinity of the piezo serving as the drive source of the Z stage 103 described above.
Microsenses (capacitance displacement gauges) 109 are arranged in the vicinity of each actuator mechanism 107 driven by a piezo element serving as a drive source arranged at three locations of the Z stage 103. Each micro sense 109 measures the movement amount of each actuator mechanism 107, that is, the movement amount of three places of the Z stage 103.
An example of attachment of the microsense 109 in FIG. 9 will be described. An initial gap adjustment of several tens of μm is required between the tapered measurement object 124 attached to the XY stage 121 and the microsense 109 attached to the Z stage 103. . By similarly arranging the taper type block 125 on the XY stage 121 on the opposite surface of the taper type measurement object 124 and moving the taper surface in the left-right direction by the adjusting screw 126, fine gap adjustment becomes possible.
An example of attachment of the microsense 109 of FIG. 10 will be described. The measurement object is fixed to the XY stage 121. The support block 127 holding the micro sense 109 attached to the Z stage 103 is configured to be movable up and down with a single adjustment screw 128. The support block 127 has a structure that can be accurately moved up and down with reference to the spigot portion provided on the pedestal 129. Each structure is locked with a fixing screw after adjustment.

FIG. 11 is an internal detail view of the P portion of FIG.
FIG. 11 shows details of drive mechanism sources arranged at three locations on the Z stage. The actuator mechanism 107 that is a drive source of the Z stage 103 includes a piezo element 324, a fixing flange 130, a flanged cylindrical casing 131, and an adjustment screw 132. The actuator mechanism 107 is fixed to the XY stage 121 via a fixing flange 130. On the opposite side, a flanged cylindrical casing 131 is attached to the Z stage 103. And the piezo element 324 is accommodated in the flanged cylindrical casing 131, and the adjustment screw 132 which can be adjusted to an up-down direction is provided in the upper end. With the structure in which the height of the Z stage 103 can be changed by moving the adjusting screw 132, the three piezo elements 324 support the full load of the Z · θ stage 122.

  Further, the above-described elastic hinge 108 supports the Z stage 103 in the X, Y, and θ directions. One region of the elastic hinge 108 is connected and fixed to the XY stage 121 via the Z pedestal 133, and the other region is directly connected and fixed to the Z stage 103.

FIG. 12 is a diagram illustrating an example of the configuration of the elastic hinge.
As shown in FIG. 12, the elastic hinge 108 uses a plate member in which two parallel thin portions 348 that are divided into three regions such as a region 342, a region 344, and a region 346 are formed. For example, the region 342 is connected and fixed to the XY stage 121 via the Z base 133 using a screw hole, and the region 344 is connected and fixed to the Z stage 103 using a screw hole. Here, an opening is formed at the center of the region 346 so as not to interfere with the movement of the flanged cylindrical casing 131 of the actuator mechanism 107. As a material of the elastic hinge 108, for example, stainless steel, titanium, aluminum or the like is suitable.

FIG. 13 is a diagram illustrating an example of the configuration of the elastic hinge in a state where the elastic hinge is moved in the Z direction.
As shown in FIG. 13, since the region 342 is fixed to the Z base 133 and the region 344 is fixed to the Z stage 103, it cannot be deformed from the fixed surface, but two thin portions 348 are formed. In addition, the two thin portions 348 can be elastically deformed to follow the movement of the piezo element via the region 346 located at the center. Here, the Z stage 103 can be supported with a simple structure because only two thin portions 348 parallel to each other that divide the plate member into three regions are formed.

FIG. 14 is a detailed view of part L in FIG.
FIG. 15 is a view showing a part of the view in the direction of the arrow L in FIG.
FIG. 16 is a diagram showing a part of the view in the direction of arrow M in FIG.
The main purpose of the holder 102 is to hold the substrate 101. The substrate 101 is mounted by the robot hand 123 in the vicinity of the center of the holder 102, and flexible blocks 137 for preventing displacement of the substrate 101 are arranged at the four corners of the installation place. Further, the surface on which the substrate 101 is installed is flattened and controlled with high accuracy, and is provided with a vacuum chuck groove 138, which is evacuated through a pipe omitted in FIG. And is configured so that no deviation occurs. In addition, the above-described reflection light amount sensor 143, transmission light amount sensor 144, temperature sensor 145, and the like are mounted on the holder 102.

FIG. 17 is a detailed view of part I in FIG.
FIG. 18 is a diagram showing a part of the N arrow view of FIG.
17 and 18 show the light amount sensor for reflection 143 and the light amount sensor for transmission 144 mounted on the holder.
The light quantity sensor is provided for checking a change in the quantity of the inspection laser light, and the quantity of light is measured by the Si photodiode 139. Factors that accompany the change in the amount of light include those caused by the light source of the laser main body, and a decrease in the amount of light due to the deterioration of the optical system 118 lens and the effect of fogging. Although not described in detail, the difference between the light amount sensor for reflection 143 and the light amount sensor for transmission 144 is due to the difference in the inspection method of the optical system, and the method of inspecting the inspection surface of the substrate 101 through the inspection light is the transmission type inspection. In addition, a reflection type inspection is a method in which inspection light is reflected by an inspection surface. In this apparatus, since both types of inspection can be performed at the same time, both types of light quantity sensors are required.

FIG. 19 is a detailed view of part G in FIG.
FIG. 20 is a diagram showing a part of the view in the direction of arrow D in FIG.
19 and 20 show a thermometer sensor (thermocouple) mounted on the holder.
The temperature sensor 145 described above is held on the pedestal 140 and attached as close to the substrate 101 as possible so that the temperature around the substrate 101 can be monitored. Although not shown in the drawing using this temperature information, the temperature in the vicinity of the substrate 101 can be controlled to be constant by feeding back to the temperature management air conditioning system in the apparatus chamber. As an example of the material of the temperature sensor 145, chromel-alumel is suitable.

FIG. 21 is a detailed view of a portion H in FIG.
FIG. 22 is a view showing a part of the E arrow view of FIG.
FIG. 23 is a detailed view of a portion J in FIG.
FIG. 24 is a diagram showing a part of the view taken along the arrow K in FIG.
FIGS. 21 to 24 show the periphery of the flexible block 137 for shock absorption and fall prevention of the substrate 101 mounted on the holder 101. A vacuum chuck groove 138 for holding the substrate 101 is also shown.
The flexible blocks 137 are arranged at the four corners of the substrate 101, and are arranged on each attachment member 340 attached to the lower surface of the holder 102 via each spacer member 342. The flexible block 137 is disposed in non-contact with the substrate 101 and is fixed to the mounting member 340 with screws or the like. The flexible block 137 has a structure with a part of the cavity in the XY direction. For example, the flexible block 137 is made of a resin material, but may be made of metal. A vacuum chuck groove 138 is formed in the mounting member 340 and is evacuated through piping. The attachment member 340 is preferably made of a resin material in order to come into contact with the substrate 101. On the attachment member 340, the flexible block 137 and the substrate 101 are fixed so as to have a predetermined amount of clearance, but the positioning of the substrate 101 is performed by the robot hand 123. Further, it is desirable to finish the surface accuracy to several μm or less and to manage the surface height of the four corners with high accuracy so that the four corner surfaces on which the substrate 101 is placed on the mounting member 340 are vacuum chucked and held with high accuracy.

FIG. 25 is a block diagram illustrating an example of an autofocus optical system and a piezo control system.
FIG. 25 shows an example of a control system that controls the piezo element 324 based on a signal from an autofocus (A / F) optical system 362 when the Z stage 103 is moved in the vertical direction. The CPU 360 that performs arithmetic processing inputs information regarding the focal position of the inspection light irradiated onto the substrate 101 on the Z stage 103 from the A / F optical system 362 as a sensor signal via the signal processing circuit 364. The CPU 360 outputs a deviation between the preset A / F target value and the sensor signal to the servo controller 366 as a deviation signal. The servo controller 366 is driven via a driver 372 that controls the piezo elements 324 in the actuator mechanisms 107 arranged at three locations in accordance with instructions from the CPU 360. The driving displacement amount of the piezo element 324 is measured by the micro sense 109, fed back to the servo controller 366, and used for controlling each piezo element 324. Therefore, the height and angle of the inspection surface can be controlled with high accuracy while finely moving the substrate 101 in the Z direction. As a result, the substrate 101 can be kept at the position of the inspection surface with higher accuracy.

As described above, according to the present embodiment, the controllability can be improved by making the Z stage 103 that finely moves in the vertical direction a linear type drive by a piezo (piezoelectric element) drive. Further, by providing the θ stage 106 that finely moves in the rotation direction, it is possible to align the rotation direction with respect to the traveling accuracy, that is, the tilt component of the substrate 101 and the XY stage 121. As a result, the inspection time can be shortened.
As described above, according to the above embodiment, by mounting, managing, and adjusting the substrate 101 on the high-accuracy Z / θ stage 122, it is possible to reduce unnecessary time by eliminating unnecessary inspection time. Can be inspected. As a result, an efficient and highly reliable substrate inspection apparatus can be provided.

Embodiment 2. FIG.
FIG. 26 is a conceptual diagram showing an example of a piping system of the θ stage levitation mechanism in the second embodiment.
FIG. 27 is a conceptual cross-sectional view of the θ stage and the Z stage for explaining the θ stage floating mechanism in the second embodiment.
Other configurations of the substrate inspection apparatus 100 according to the second embodiment are the same as those of the first embodiment, and thus the description thereof is omitted. As described above, the Z stage 103 is formed with the opening h for floating the θ stage 106 disposed on the Z stage 103 using gas, here, air (Air). And the board | substrate inspection apparatus 100 in Embodiment 2 is further provided with the flow volume adjustment valve 352 which adjusts the supply_amount | feed_rate of the gas supplied to each such opening part h, respectively. With this configuration, the amount of gas supplied to each opening h can be adjusted. As a result, the flying position can be controlled. Further, although the flow rate adjusting valve is used here, the same effect can be obtained even if an air pressure adjusting valve is used.

  The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.

  In addition, although descriptions are omitted for parts and the like that are not directly required for the description of the present invention, such as a device configuration and a control method, a required device configuration and a control method can be appropriately selected and used.

  In addition, all substrate inspection apparatuses, substrate inspection methods, and stage mechanisms that include the elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention.

1 is a conceptual diagram showing a configuration of a substrate inspection apparatus in a first embodiment. 5 is a plan view showing an example of a configuration of a Z · θ stage in the first embodiment. FIG. It is a figure which shows a part of X arrow directional view of FIG. It is a figure which shows a part of Y arrow view of FIG. It is a figure which shows a part of Z arrow line view of FIG. It is a figure which shows a part of A arrow view of FIG. It is a figure which shows a part of C arrow line view of FIG. It is a figure which shows a part of B arrow line view of FIG. FIG. 6 is a detailed view of a W part in FIG. 5. FIG. 4 is a detailed view of a V part in FIG. 3. FIG. 10 is an internal detail view of a P part in FIG. 9. It is a figure which shows an example of a structure of an elastic hinge. It is a figure which shows an example of a structure of the elastic hinge in the state which moved to the Z direction. FIG. 3 is a detailed view of part L in FIG. 2. It is a figure which shows a part of L arrow line view of FIG. It is a figure which shows a part of M arrow line view of FIG. It is detail drawing of the I section of FIG. It is a figure which shows a part of N arrow line view of FIG. It is detail drawing of the G section of FIG. It is a figure which shows a part of D arrow line view of FIG. It is detail drawing of the H section of FIG. It is a figure which shows a part of E arrow line view of FIG. It is detail drawing of the J section of FIG. It is a figure which shows a part of K arrow line view of FIG. It is a block diagram which shows an example of an autofocus optical system and a piezo control system. 6 is a conceptual diagram illustrating an example of a piping system of a θ stage levitation mechanism in Embodiment 2. FIG. FIG. 5 is a conceptual cross-sectional view of a θ stage and a Z stage for explaining a θ stage floating mechanism in a second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Substrate inspection apparatus 101 Substrate 102 Holder 103 Z stage 104, 105 Reflective mirror 106 θ stage 107 Actuator mechanism 108 Elastic hinge 109 Micro sense 112 θ drive linear actuator 113 Elastic member 114 θ Vacuum chuck groove 115 Light emitting part 116 Reflective mirror 121 XY stage 138 Vacuum chuck groove 141 Laser light 143 Reflection light quantity sensor 144 Transmission light quantity sensor 145 Temperature sensor 308 Rod 310 Tension springs 342, 344, 346 Region 348 Thin part

Claims (11)

In a substrate inspection apparatus for inspecting a substrate to be inspected,
An XY stage that moves horizontally;
A Z stage disposed on the XY stage and moving in the vertical direction;
Three piezoelectric elements that move the Z stage up and down at three locations;
A board inspection apparatus comprising: The substrate inspection apparatus further includes:
A θ stage disposed on the Z stage and moving in the rotational direction;
A linear drive unit having a rod disposed on the Z stage and moving in a linear direction;
An elastic member connected to the rod and rotating the θ stage in accordance with the movement of the rod while elastically deforming;
The substrate inspection apparatus according to claim 1, further comprising: The substrate inspection apparatus further includes an elastic hinge connected to the XY stage and the Z stage and supporting the Z stage,
The board inspection apparatus according to claim 1, wherein a plate member having two thin portions parallel to each other divided into three regions is used as the elastic hinge.   2. The substrate inspection apparatus according to claim 1, further comprising a tension spring that is connected to the XY stage and the Z stage and pressurizes the Z stage toward the XY stage. . The substrate to be inspected is disposed on the θ stage,
The said board | substrate inspection apparatus is further provided with the reflective mirror for measuring the position of a X direction or a Y direction using the laser beam arrange | positioned on the said Z stage. Board inspection equipment.   The substrate inspection apparatus according to claim 1, wherein the substrate inspection apparatus further includes three displacement meters that measure the amount of movement of the Z stage by each Z-direction drive unit of the three Z-direction drive units. apparatus. The Z stage is formed with an opening for floating the θ stage using gas,
The substrate inspection apparatus according to claim 2, further comprising a flow rate adjusting valve that adjusts a supply amount of a gas supplied to the opening.   The substrate inspection apparatus according to claim 2, wherein the θ stage is vacuum chucked to the Z stage. The substrate to be inspected is disposed on the θ stage,
The substrate inspection apparatus further includes a laser sensor on the θ stage for measuring the presence or absence of the substrate to be inspected by irradiating a side surface of the substrate to be inspected with a laser beam obliquely in a horizontal direction. The substrate inspection apparatus according to claim 2. The substrate inspection apparatus further includes:
A holder disposed on the θ stage and holding the substrate to be inspected;
A light quantity measuring unit arranged on the holder for measuring the quantity of inspection light for inspecting the substrate to be inspected;
The substrate inspection apparatus according to claim 2, further comprising:   The substrate inspection apparatus according to claim 10, further comprising a temperature sensor disposed on the holder in a non-contact manner with the substrate to be inspected.

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