JP3919566B2 - Classification apparatus and method for manufacturing substrate for electronic device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic device substrate used for a photomask blank and a phase shift mask blank, a manufacturing method for obtaining an ultra-flat and ultra-smooth substrate, and an electronic device substrate necessary for obtaining the substrate. The present invention relates to a classification device for classifying by thickness (thickness).
[0002]
[Prior art]
A glass substrate for an electronic device used for a photomask blank is required to have high flatness and high smoothness. In order to obtain a glass surface having high flatness and high smoothness, multiple stages of precision polishing are usually performed using a double-side polishing apparatus as described in JP-A-1-40267. By this multi-stage precision polishing, both surfaces are polished using abrasive grains having a relatively large particle diameter, and then a glass surface having a small surface roughness is obtained using abrasive grains having a small particle diameter.
[0003]
As the double-side polishing apparatus used here, a so-called batch processing type polishing apparatus is generally used. This is because the batch processing type polishing apparatus can set a plurality of glass substrates at the same time, and can polish both sides of the set glass substrates at once by a single operation. Specifically, in a multi-stage precision polishing process, the glass substrates that have finished the previous polishing process are collected in a predetermined location, and the collected glass substrates are sequentially put into a batch processing type polishing apparatus for each appropriate amount. Thus, a plurality of glass substrates having high flatness and high smoothness are obtained.
[0004]
[Problems to be solved by the invention]
However, when a batch processing type polishing apparatus is used, there are the following problems. That is, in the precision polishing process in a plurality of stages, the glass substrate that has finished the previous polishing process may have a difference in the thickness of the glass substrate depending on the polishing apparatus or batch processing. When such a difference in thickness of the glass substrate is set in a double-side polishing apparatus in the next polishing step, it is compared with a thick plate W1 having a relatively large thickness as shown in FIG. When the target thin plate W2 is mixed, as shown in FIG. 18 (b), when the double-side polishing is performed, the plates W1, W2,... Are not aligned, and the thin plate W2 is sufficiently scratched. It may not be removed and high flatness and high smoothness may not be obtained. This becomes a serious problem as it goes to a precision polishing process and an ultra-precision polishing process with less polishing margin (10 μm or less).
[0005]
This invention is made | formed in view of this problem, and it aims at providing the manufacturing method of the glass substrate for electronic devices of high flatness and high smoothness. It is another object of the present invention to provide a technique for effectively utilizing a batch processing type polishing apparatus in manufacturing a substrate having high flatness and high smoothness (for example, a glass substrate for electronic devices).
[0006]
[Means for Solving the Problems]
The classification device according to the first aspect of the present invention that achieves the above object includes a supply unit that supplies a plate-like body, a cassette arrangement unit that arranges a plurality of cassettes in which the plurality of plate-like bodies are stored, and the supply unit The plate thickness measuring means for measuring the plate thickness of the plate-like body supplied by the apparatus, and the plurality of cassettes in which the plate-like body whose thickness is measured by the plate thickness measuring means are arranged in the cassette arrangement portion. And a control means for controlling the storage mechanism so as to store the plate-like body in each cassette according to the plate thickness based on the measurement result of the plate thickness measuring means. It is characterized by that.
[0007]
In the classification device according to the first aspect of the present invention, a plurality of cassettes storing a plurality of plate-like bodies are arranged in advance in the cassette arrangement unit. And if a plate-shaped object is supplied to a supply part, a plate thickness measurement means will measure the plate | board thickness of the plate-shaped object. The storage mechanism stores the plate-like body whose plate thickness is measured by the plate thickness measuring unit in any of a plurality of cassettes arranged in the case arrangement unit. In the process, the control unit controls the storage mechanism so that the plate-like body is stored in each cassette according to the plate thickness based on the measurement result of the plate thickness measuring unit. As a result, plate-like bodies having approximate plate thicknesses are collected in each of the cassettes arranged in the cassette arrangement unit. Therefore, if the cassettes are unloaded from the cassette placement unit and the plate-like bodies having approximate thicknesses are collectively fed into a batch processing type polishing apparatus, all the plate-like bodies are used during double-side polishing. The icicles are almost complete.
As a result, in a multi-stage precision polishing process, a sufficient polishing margin for removing scratches and the like is secured on all the plate-like bodies generated in the previous stage, so that high flatness and high smoothness can be obtained. . In addition, since a sufficient polishing margin is secured for all the plate-like bodies, it is surely avoided that scratches and the like remain on them, and each plate-like body is polished more than necessary. You can avoid things. Thus, a batch processing type polishing apparatus is effectively utilized.
[0008]
According to a second aspect of the present invention, in the classification device according to the first aspect, the plate thickness measuring means face each other arranged parallel to each other with a wider interval than the plate thickness of the plate-like body. A capacitor having a pair of electrode plates, and positioning means for positioning the plate-like body supplied from the supply unit so as not to contact the electrode plates between the pair of electrode plates, A plate thickness of the plate-like body is detected based on a comparison between a capacitance of the capacitor and a given reference capacitance when the plate-like body is positioned between the pair of electrode plates by a positioning unit. And
[0009]
According to the second aspect of the present invention, the plate-like body supplied from the supply unit is positioned so as not to contact each electrode plate between the pair of electrode plates. Detecting with is realized. Thereby, it is possible to prevent the plate-like body from being scratched.
[0010]
Here, in order to improve the measurement accuracy of the plate thickness measuring means, it is preferable to place at least the plate thickness measuring means in an environment (for example, a nitrogen atmosphere) in which temperature and humidity are controlled.
[0011]
According to a third aspect of the present invention, in the classification device according to the second aspect, the positioning means includes a gripping member for gripping the plate-like body, and the gripping member includes an edge in the plate state. And a robot hand for delivering the plate-like body supplied from the supply unit to and from the gripping member.
According to the third aspect of the present invention, the robot hand transfers the plate-shaped body supplied from the supply unit to and from the gripping member.
[0012]
As a preferred aspect, in the classification apparatus according to any one of the first to third aspects, such as the classification apparatus according to the fourth aspect of the present invention, the plate thickness measuring means is returned to a predetermined reference position. A biasing means for biasing is provided.
[0013]
For example, the urging means may have a structure having an elastic body, specifically, a turntable that rotatably supports the plate thickness measuring means, and the plate along a plane parallel to the turntable. A guide member that guides the thickness measuring means in a freely displaceable manner, and the turntable and the guide member may be provided with an elastic body.
[0014]
With this configuration, when an inertial force or the like is applied to the plate thickness measuring unit, the plate thickness measuring unit is freely rotated by the turntable and is freely displaced by being guided by the guide member. And since a plate-shaped object is correctly positioned with respect to a plate | board thickness measuring means, the dispersion | variation in a measurement result will reduce and a measurement precision will also improve. Furthermore, since the elastic body is used to return to the predetermined reference position, it is possible to prevent cracking and chipping accompanying the delivery of the plate-like body by the robot hand. The reason is as follows.
[0015]
When the plate-like body is transferred from the robot hand to the gripping member, the weight of the plate-like body is added to the plate thickness measuring means. At that time, the plate thickness measuring means rotates freely by the turntable and moves flexibly as a whole while being guided by the guide member and freely displaced. Along with the movement, the edge of the plate-like body is fitted into the groove in a well-positioned state while being guided by the groove having a substantially V-shaped cross section formed in the gripping member. Thus, since the plate-like body can be accurately positioned at a predetermined position between the pair of electrode plates, variations in measurement results when measuring the plate thickness of the same plate-like body can be reduced, and the accuracy of the measurement results can be improved. After the plate-like body is separated from the robot hand, it is returned to a predetermined reference position by the elastic body of the biasing means, so that the plate-like body is securely gripped by the robot hand after the measurement and the plate-like body is cracked. Prevents chipping.
[0016]
A classification apparatus according to a fifth aspect of the present invention is the classification apparatus according to any one of the first to fourth aspects, wherein each of the plurality of cassettes arranged in the cassette arrangement unit is stored in the cassette. Input means for assigning a range of the plate thickness of the plate-like body, and the control means has a plate thickness in a range assigned by the input means to each cassette arranged in the cassette arrangement portion. The storage mechanism is controlled to store the state body.
[0017]
In the fifth aspect of the present invention, the operator uses the input means to assign a range of plate thicknesses of the plate-like bodies stored in the cassette for each of the plurality of cassettes arranged in the cassette arrangement unit. Then, the control means controls the storage mechanism so as to store the plate-like body having the plate thickness in the range assigned by the input means in each cassette arranged in the cassette arrangement section. As a result, plate-like bodies having different thicknesses for each cassette can be aggregated, and plate-like bodies having the same range of plate thicknesses can be aggregated over a plurality of cassettes.
[0018]
According to the sixth aspect of the present invention, there is provided a plate-like body supply step of supplying a plurality of electronic device substrates having different thicknesses to the supply unit in the classification device according to any one of the first to fifth aspects, A cassette unloading step of unloading at least one of the cassettes in which the electronic device substrate is stored from the cassette placement section of the classification apparatus; and then a plurality of the electronic devices stored in the unloaded cassette There is also provided a method of manufacturing a substrate for an electronic device, comprising: a precision polishing step of precisely polishing the substrate to have a desired surface roughness by a polishing apparatus.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2 are diagrams showing a classification apparatus according to an embodiment. FIG. 1 is a plan view thereof, and FIG. 2 is a front view thereof. As shown in FIG. 1, the classification device 1 includes a loader unit 2, an unloader unit 3, a plate thickness measuring unit 11 that measures the plate thickness of the workpiece W, and a transfer device 5 that transfers the workpiece W.
[0020]
The work W mentioned here is caused by a slight difference in polishing conditions or a difference in polishing apparatus depending on a batch processing type polishing apparatus in a manufacturing process including a polishing process of a glass substrate for an electronic device used for a photomask blank. It refers to a plate-like body such as a glass substrate having a different thickness. The workpiece W is made of glass such as quartz glass or soda lime glass. When the workpiece W is arranged in an electric field, the electric field enters the inside of the workpiece W to cause polarization. That is, the workpiece W as a plate-like body is a dielectric (insulator).
[0021]
The loader unit 2 includes a loader loading unit 21 for loading a cassette (storage container) K in which workpieces W (works having different thicknesses) before sorting are stored (contained), and a transfer device 5 to load the workpiece W. And a loader take-out unit 22 for taking out the cassette K that has been completely taken out.
The cassette K loaded in the loader loading unit 21 is transported to a predetermined position where the cassette is taken out by the transport device 23 as shown in FIG. The cassette K which has been transported to a predetermined position and is in an empty state is transferred to the loader take-out unit 22 by the conveyor of the transfer device 5 provided between the loader loading unit 21 and the loader take-out unit 22. In FIG. 1, the flow of the cassette K between the loader loading part 21 and the loader take-out part 22 is indicated by arrows.
[0022]
The unloader unit 3 includes three stockers: a first stocker 31, a second stocker 32, and a third stocker 33. As shown in FIG. 2, each of these stockers 31, 32, and 33 is configured to store cassettes K in four stages in the Z-axis direction (vertical direction in FIG. 2). Each stage can be classified by thickness.
[0023]
Further, each stage of each stocker is provided with a transport device such as a conveyor so as to transport the cassette K storing the workpieces W whose thicknesses are classified to a predetermined position. That is, as shown in FIG. 2, for example, transport devices 331, 332, 333, and 334 are provided at each stage of the third stocker 33, respectively. Further, although not shown in FIG. 2, transport devices 311, 312, 313, and 314 are provided in the respective stages of the first stocker 31, and transport devices 321 are provided in the respective stages of the second stocker 32. , 322, 323, 324 are provided (see FIG. 6).
[0024]
Further, sensors for detecting whether or not the cassette K placed on the transfer device is full are arranged near the respective transfer devices of the stockers 31, 32, and 33, respectively. Specifically, as shown in FIG. 1, for example, sensors 334 a and 334 b are arranged in the vicinity of the transport device 334. Similarly, although not shown in FIG. 1, two sensors are arranged in the vicinity of each transport device.
That is, sensors 311a and 311b are located near the transport device 311, sensors 312a and 312b are located near the transport device 312, sensors 313a and 313b are located near the transport device 313, sensors 314a and 314b are located near the transport device 314, Sensors 321a and 321b are in the vicinity of the transport device 321; sensors 322a and 322b are in the vicinity of the transport device 322; sensors 323a and 323b are in the vicinity of the transport device 323; sensors 324a and 324b are in the vicinity of the transport device 324; Sensors 331a and 331b are provided near 331, sensors 332a and 332b are provided near the transfer device 332, sensors 333a and 333b are provided near the transfer device 333, and sensors 334a and 334b are provided near the transfer device 334, respectively. (See FIG. 6).
[0025]
As shown in FIGS. 1 and 2, the transfer device 5 is disposed on the stocker of the unloader unit 3 from the plate thickness measuring unit 11 to the plate thickness measuring unit 11 from the inside of the cassette K in the loader loading unit 21. Conveying rails 51, 52, and 53 are configured to extend in the X-axis direction, the Y-axis direction, and the Z-axis direction, respectively, so that they can be transferred into a predetermined cassette K. The transport rail 52 is provided with a robot hand 6 that grips the workpiece W.
[0026]
Further, as shown in FIG. 2, a temporary work storage place 7 is provided below the loader loading unit 21. In the cassette K in the temporary work storage place 7, a work W or the like deviating from the plate thickness condition setting can be temporarily stored. The workpieces W transferred from the plate thickness measuring unit 11 to the workpiece temporary storage place 7 can be classified again by the classification device 1 when the workpiece W has reached a certain quantity.
[0027]
Below, the structure of the plate | board thickness measurement part 11 is demonstrated in detail.
FIG. 3 is a front view of the plate thickness measuring unit 11. As shown in FIG. 3, the plate thickness measuring unit 11 is configured based on a bottom plate 111.
Below the bottom plate 111, a turntable 110a that supports the entire plate thickness measuring section 11 so as to be rotatable, and a first guide that displaceably guides the entire plate thickness measuring section 11 along a plane parallel to the turntable 110a. A 1LM guide 110b and a second LM guide 110c are arranged.
[0028]
FIG. 4 is a schematic view of the plate thickness measuring unit 11 as seen from the plane direction. In FIG. 4, the arrow indicates the movable direction of the plate thickness measuring unit 11. As shown in the figure, the first LM guide 110b guides the entire plate thickness measuring unit 11 so as to be displaceable in the left-right direction in plan view. Further, the second LM guide 110c guides the entire plate thickness measuring unit 11 so as to be displaceable in the front-rear direction (vertical direction in FIG. 4) in plan view.
[0029]
FIG. 4 shows a state in which the plate thickness measuring unit 11 is at the reference position. Although not shown, when the plate thickness measuring unit 11 is displaced from the reference position, the plate thickness measuring unit 11 is used as a reference. The turntable 110a, the first LM guide 110b, and the second LM guide 110c are provided with an elastic body that urges them back to the position. As a result, the plate thickness measuring section 11 moves flexibly as a whole, while the movement is quickly attenuated. In addition, a spring, rubber | gum, etc. can be used as an elastic body.
[0030]
The bottom plate 111 is provided with a pair of left and right support columns 116 and 117 extending in the normal direction, and circular electrode plates 118 and 119 are fixed to the support columns 116 and 117, respectively. In FIG. 3, only the support column 116 and the electrode plate 118 are shown.
The pair of electrode plates 118 and 119 are arranged in parallel with each other so as to face each other with a gap slightly wider than the thickness of the workpiece W, and constitute a capacitor. When the classification device 1 is in operation, an AC voltage is supplied to this capacitor from a power source (not shown).
[0031]
Here, the distance between the electrode plates 118 and 119 will be described. The thickness of the workpiece W handled in the classification apparatus 1 is, for example, approximately 6 [mm], and more specifically, the thickness in the range of 6.100 [mm] to 6.400 [mm] is classified. It is targeted. In the production line to which the classification apparatus 1 is applied, a board having a thickness of 6.300 [mm] is mainly handled.
Therefore, it is preferable that the distance between the electrode plates 118 and 119 is at least 10 [mm] when the plate thickness measurement accuracy and the positioning accuracy of the robot hand 6 are considered. This is because if the distance between the electrode plates 118 and 119 is designed too narrow, the measurement accuracy is improved, but the workpiece W may come into contact with the electrode plates 118 and 119 during delivery to the robot hand 6. Because.
Specifically, the distance between the electrode plates 118 and 119 is 12 [mm] slightly wider than the plate thickness of the workpiece W, and the upper limit of the plate thickness that can be measured is 9.00 [mm].
Needless to say, the thickness of the workpiece W and the distance between the electrode plates 118 and 119 handled in the classification apparatus 1 are not particularly limited.
[0032]
Now, a holding member 124 is fixed to the bottom plate 111 as positioning means that is interposed between the pair of electrode plates 118 and 119 in a state where the workpiece W is erected. The holding member 124 includes a pair of grip portions 121 and 122 that grip both the left and right side surfaces of the workpiece W, and a support portion 123 that supports the lower side surface of the workpiece W.
[0033]
Further, V-grooves having a substantially V-shaped cross section are formed in the abutting portions that abut the workpiece W in the gripping portions 121 and 122 (see FIG. 17). Specifically, as shown in FIG. 17, V-grooves 1211 a and 1212 a are formed in the abutting parts 1211 and 1212 of the one gripping part 121, respectively, and the abutting part 1221 and the other gripping part 122 are abutted. V-grooves 1221a and 1222a are formed in 1222, respectively. And it has comprised so that the side surface of the workpiece | work W may fit in each of these V-grooves.
[0034]
The support part 123 is fixed to the bottom plate 111. A V-groove (not shown) is also formed in the abutting portion of the supporting portion 123 that abuts on the workpiece W, and the lower surface of the workpiece W is fitted into the V-groove.
The opening degree (opening angle) of each V-groove is not particularly limited, but is designed to be approximately 90 degrees, for example.
[0035]
Here, the groove bottoms of the V grooves in the pair of gripping portions 121 and 122 and the support portion 123 pass through the midpoints of the line segments representing the distances between the pair of electrode plates 118 and 119, and the electrode plates 118, Since it is arrange | positioned on the plane parallel to 119, the workpiece | work W can be positioned correctly.
Specifically, when the workpiece W is fitted into each V-groove, a minute gap is evenly secured between the workpiece W and the electrode plate 128 and between the workpiece W and the electrode plate 129. In addition, the workpiece W is centered between the electrode plates 118 and 119.
[0036]
Moreover, each said contact part consists of an elastic body, and this prevents the periphery of the workpiece | work W from being damaged.
Here, it is preferable to employ hard rubber, resin, or the like as the elastic body. When these are employed, not only the scratches and the like can be prevented from adhering to the work W, but also the work W can be prevented from slipping, so that it can be securely held or held. Thereby, the reliability of the measurement result of the plate thickness measuring unit 11 can be improved.
[0037]
Although not shown, one electrode plate 119 is provided with a sensor head among the pair of electrode plates 118 and 119 constituting the capacitor. The sensor head includes the capacitance of the capacitor 120 when the workpiece W is not interposed between the electrode plates 118 and 119 and the capacitance of the capacitor 120 when the workpiece W is interposed between the pair of electrode plates 118 and 119. Based on the comparison with the electrostatic capacity (given reference capacity), the thickness of the workpiece W is measured.
[0038]
The plate thickness measurement principle using the sensor head is as follows. That is, the capacitance C [Coulomb] of the capacitor 120 is such that the distance between the electrode plates 118 and 119 is d, the surface area of each electrode plate facing the defective product W is S, and the vacuum dielectric constant is ε. ₀ , The dielectric constant of the substance interposed between the electrode plates ₁ Is given by the following equation.
C = (ε ₀ × ε ₁ × S) ÷ d
[0039]
Where ε ₀ , S, d are known and their values are constant. The capacitance of the capacitor when the workpiece W is not interposed between the electrode plates 118 and 119 is ε ₁ Corresponds to the dielectric constant of air (approximately 1) (ε ₀ XS) ÷ d, and this value is constant. On the other hand, when a workpiece W is interposed between the electrode plates 118 and 119, ε ₁ Changes from approximately 1 to a value corresponding to the thickness of the workpiece W, so that the capacitance of the capacitor varies. When the capacitance of the capacitor fluctuates, the voltage applied to the capacitor fluctuates, so that the plate thickness of the workpiece W can be measured based on the fluctuation of the voltage.
[0040]
Here, when the sizes of the electrode plates 118 and 119 are constant, the distance d is preferably designed to be as narrow as possible within a range wider than the plate thickness of the workpiece W. As shown in FIG. 5A, when the distance between the electrode plates 118 and 119 is designed to be wide, the electric lines of force E1 greatly swell outside the electrode plates at the edge of each electrode plate. It depends. In this case, variation occurs in the direction of the electric force line E1, leading to a decrease in measurement accuracy. On the other hand, as shown in FIG. 5B, when the electrode plates 118 and 119 are brought close to each other, the electric force lines E2 are directed in the normal direction of the respective electrode plates, so that there is a variation in the direction of the electric force lines E2. It is possible to perform accurate measurement without causing
Further, the variation in the direction of the lines of electric force depends on the relative relationship between the size of each electrode plate 118 and 119 and the distance between them. That is, by increasing the size of each of the electrode plates 118 and 119, the variation in the direction of the electric force line E1 can be eliminated, and a plate thickness of 6 [mm] or more can be measured with good accuracy.
[0041]
Also, ε ₁ Since the thickness varies depending on the humidity, the plate thickness measuring unit 11 is arranged in an atmosphere adjusted to a predetermined humidity. Specifically, most of the plate thickness measuring unit 11 is covered with a box-shaped housing, and the inside of the housing is always kept at a low humidity by a measurement accuracy stabilizing device (not shown). It is made up. This prevents variations in the plate thickness detection results due to changes in humidity.
[0042]
Although the main part of the classification device 1 has been described above, the classification device 1 includes an operation panel as an input means for an operator to give a desired operation instruction. This input means may be provided in the classification device 1 itself like various operation buttons, or may be externally attached to the classification device 1 such as a personal computer.
[0043]
Next, the internal configuration of the classification device 1 will be described. FIG. 6 is a block diagram showing the internal configuration of the classification device 1. In the figure, reference numeral 16 denotes a control unit that is mounted on the classification device 1 and controls the operation of the classification device 1, and is constituted by a microprocessor or the like including a CPU (Central Processing Unit) and a memory.
In detail, the control part 16 is based on the operation signal given from the operation panel 15, the measurement result of the plate | board thickness measurement part 11, and the detection result of the sensors 331a-344b, and the conveying apparatuses 23 and 311-314. , 321 to 324, 331 to 334, the transport rails 51 to 53, and the control of the robot hand 6.
[0044]
As shown in FIG. 6, the plate thickness measuring unit 11 includes a sensor head 11a, an amplifier 11b, a power supply unit 11c, and a multimeter (voltmeter) 11d.
As described above, the sensor head 11a outputs a voltage corresponding to the thickness of the workpiece W.
The amplifier 11b is powered and driven by the power supply unit 11c, and amplifies the voltage output by the sensor head 11a. The amplifier 11b has a built-in calibration resistor. The resistance has a resistance value calibrated based on a voltage output in advance when measuring a prototype having a known plate thickness.
The multimeter 11d displays the voltage value of the calibrated voltage output by the amplifier 11b, A / D converts the voltage, and outputs it to the control unit 16.
The calibration of the detection result can also be realized by software. In that case, a program describing the calibration process may be stored in the memory of the control unit 16.
[0045]
The operation panel 15 includes a display unit that constitutes a touch panel. The display mode of the display unit will be described below with reference to FIGS.
First, when the classification device 1 is operated, a title screen 130 as shown in FIG. 7 is displayed on the display unit. On the title screen 130, screen selection menus 131 to 137 for selecting other screens to be described later and item selection menus 138 to 141 for selecting items are displayed.
Here, the item represents the type of the workpiece W. Accordingly, for example, when classifying the type of workpiece W “RC”, the item selection menu 139 is touched.
[0046]
The column 142 displays the batch configuration status. Here, the batch refers to a group of workpieces that are simultaneously loaded into the polishing apparatus, and one batch of workpieces W is stored in one or a plurality of cassettes K. In the column 143, when an error occurs during the automatic operation of the classification device 1, the content of the error, that is, the reason why the automatic operation cannot be performed is displayed in an easily understandable manner. The column 144 displays the number of workpieces that have been continuously measured up to now. The column 145 displays the continuous operation time up to the present time. A column 146 displays the thickness value of the workpiece W currently being measured.
[0047]
Further, the title screen 130 includes an automatic start menu 147 for instructing automatic operation of the classification device 1, an operation preparation OK menu 148 for restarting the operation of the classification device 1 once it is stopped, and the operation of the classification device 1. Are temporarily displayed, a stop menu 150 for terminating the operation of the classification apparatus 1, and a work unloading menu 151 for instructing unloading of the work W are displayed.
[0048]
When the operator touches the screen selection menu 131, the title screen 130 changes to the monitor screen 155 shown in FIG.
On the monitor screen 155, a graph 156 showing the transition of the plate thickness measurement value is displayed. In this graph 156, the thick line indicated by reference numeral 156a represents the upper limit of the standard for thickness, and the thick line indicated by reference numeral 156b represents the lower limit of the standard for thickness. Thereby, the operator can visually grasp whether the thickness of the workpiece W is between the thick line 156a and the thick line 156b.
The column 157 displays the thickness value of the workpiece W currently being measured. The column 158 displays information indicating whether or not the cassette K arranged in each stocker of the unloader unit 3 is full based on the detection results of the sensors 311a to 334b.
When the operator touches the menu 159 on the monitor screen 155, this screen returns to the title screen 130 again.
[0049]
When the operator touches the screen selection menu 132 on the title screen 130, the title screen 130 transitions to the monitor screen 160 shown in FIG.
In the monitor screen 160, a classification width (thickness division width) [μm] described later is displayed in a column 161. In the column 162, a standard representing the thickness range of the workpiece W that can be input to the polishing process used in the next process is displayed. In FIG. 9, it is assumed as an example that the upper limit of the standard is set to 6.000 [mm] and the lower limit is set to 6.400 [mm]. In the column 163, for each cassette K, the frequency with which the workpiece W is stored in that cassette K is displayed. In addition, when the standard range is divided into a plurality of classifications with an arbitrary thickness width, which classification is assigned to each cassette K is displayed. The operator can arbitrarily change the assignment by touching this field 163.
In the column 164, the thickness of the workpiece W currently being measured is displayed.
When the menu 165 is touched on the monitor screen 160, the screen returns to the title screen 130 again.
[0050]
When the operator touches the screen selection menu 133 on the title screen 130, the title screen 130 transitions to the monitor screen 166 shown in FIG.
On this monitor screen 166, when trouble occurs, it is possible to quickly monitor programs and sensor lighting.
[0051]
When the operator touches the screen selection menu 134 on the title screen 130, the title screen 130 transitions to a trouble display screen 170 shown in FIG.
In the figure, reference numeral 171 is a schematic diagram schematically showing the configuration of the classification device 1. In this schematic diagram, the location where the trouble has occurred is marked and displayed. As a result, the worker can visually grasp the place where the trouble has occurred, and can quickly cope with this.
Further, the name of the trouble occurrence location is displayed in the column 172. In a column 173, a method for dealing with the trouble is specifically displayed.
If the menu 174 is touched on the trouble display screen 170, the screen returns to the title screen 130 again.
[0052]
When the operator touches the screen selection menu 135 on the title screen 130, the title screen 130 transitions to an origin return screen 175 shown in FIG.
On the origin return screen 175, the origin return of the classification device 1 is instructed before the automatic operation or the test mode. In the figure, reference numeral 176 is a schematic diagram schematically showing the configuration of the classification device 1. In this schematic diagram, the position where the origin is returned is marked and displayed.
Reference numeral 177 is a menu for instructing the return to the origin of the turntables 51 and 52. Reference numeral 178 is a menu for instructing the return of the origin of the turntables 61 and 62. Reference numeral 179 is a menu for instructing the return of the origin of the turntables 71 and 72. Reference numeral 180 is a menu for instructing the return of the origin of the gripping parts 121 and 122. Reference numeral 181 denotes a menu for instructing the origin return in the vertical direction of the transport rail 53. Reference numeral 182 denotes a menu for instructing the return of the origin of the grip portion of the robot hand 6.
When the operator touches any of the above menus, the control unit 16 returns the position corresponding to the menu to the origin. In the process, the control unit 16 marks and displays the position where the origin is returned in the schematic diagram 176.
Further, when the operator touches the menu 183 on the origin return screen 175, the screen changes to a manual screen 186 described later, touches the reference numeral 184, transitions to the test mode screen 200 described later, and touches the menu 185 to the title screen 130. Transition.
[0053]
When the operator touches the screen selection menu 136 on the title screen 130, the title screen 130 transitions to a manual screen 186 shown in FIG. In this manual screen 186, each part which comprises a classification apparatus is operated manually.
In the figure, reference numeral 187 is a schematic diagram schematically showing the configuration of the classification device 1. In this schematic diagram 187, a manually operated portion is marked and displayed. Reference numeral 188 denotes a menu for operating the conveying devices 311, 312, 313, and 314. Reference numeral 189 denotes a menu for operating the conveying devices 321, 322, 323 and 324. Reference numeral 190 denotes a menu for operating the conveying devices 331, 332, 333, and 334. Reference numeral 191 denotes a menu for operating the grip portions 121 and 122. Reference numeral 192 denotes a menu for operating the grip portion of the robot hand 6. Reference numerals 193 a to 193 f are menus for moving the robot hand 6. Reference numeral 194 denotes a menu for moving the robot hand 6 in the vertical direction (Z-axis direction). Reference numeral 195 is a menu for moving the robot hand 6 in the left-right direction (Y-axis direction). Reference numeral 196 denotes a menu for moving the robot hand 6 in the front-rear direction (X-axis direction). Reference numeral 197 denotes a menu for causing the plate thickness measuring unit 11 to start measurement.
When the worker touches any one of the menus, the control unit 16 drives the part corresponding to the menu. In the process, the control unit 16 marks and displays the driving part in the schematic diagram 187.
On the manual screen 186, when the operator touches the menu 198, the screen returns to the origin return screen 175, and when the operator touches the menu 199, the screen transitions to the title screen 130.
[0054]
When the operator touches the screen selection menu 137 on the title screen 130, the title screen 130 transitions to the test mode screen 200 shown in FIG. On the test mode screen 200, the plate thickness measuring unit 11 can be started up or adjusted.
In the figure, reference numerals 201 to 205 are columns for inputting the plate thickness of the original device. Here, plate thicknesses of five types of original equipment are input. When the operator selects any master and touches the operation preparation OK menu, the thickness of the master is detected, and the detection result is displayed in the column 206. On this screen, the detection result of the plate thickness measuring unit 11 can be calibrated.
In the test mode screen 200, when the operator touches the menu 209, the screen returns to the origin return screen 175, and when the operator touches the menu 210, the screen transitions to the title screen 130.
[0055]
A condition setting screen 220 as shown in FIG. 15 is displayed on the touch panel of the operation panel 15. The condition setting screen 220 is a so-called secret screen, and is displayed by performing a specific operation such as inputting a password on the operation panel 15. Thereby, it is possible to prevent the setting contents from being changed due to an erroneous operation by the operator.
In FIG. 15, the standard setting menu 221 includes, for each of a plurality of standards, an item name corresponding to the standard, an upper limit value and a lower limit value of the standard, a thickness division width when the standard is divided into a plurality of classifications, And the center value representing the most frequently used thickness value in the range of the standard is displayed in association with each other.
[0056]
When the standard setting menu 221 is touched, the cursor 221a moves to the touched location. The operator can set the standard with the cursor 221a. For example, in FIG. 15, in the standard corresponding to the item name “RC”, the upper limit value is set to 6.000 [mm], the lower limit value is set to 6.200 [mm], and the thickness division width is set to 10 [μm]. It is assumed that the center value is set to 6.150 [mm].
[0057]
In addition, the operator can assign the cassette K for each classification of the standard set by the cursor 221a in the cassette assignment menu 222. Make up one batch in each classification.
The number of classifications is determined by the upper and lower limits of the standard and the thickness division width. When the number of classifications is smaller than the number of cassettes K arranged at ports 6 and 7, a plurality of cassettes K can be assigned to the same classification. In this case, a plurality of cassettes K may be allocated near the center value. The center value can also be changed with the cursor 223.
[0058]
Specifically, in the cassette assignment menu 222 in FIG. 15, labels of circle 1 to circle 12 are given to 12 cassettes K, respectively. Labels 1, 2,... Are assigned to the respective classifications of the standard corresponding to the item name “RC”. Then, the label of the cassette K is displayed in association with each classification label. Specifically, the center value is set between the classification with the label 7 and the classification with the label 8, and two cassettes are assigned to the classification with the labels 7 and 8, respectively. ing.
The contents set on the condition setting screen 220 are stored in the nonvolatile memory of the control unit 16.
In this condition setting screen 220, when the menu 224 is touched, the screen returns to the title screen 130 again.
[0059]
In determining the upper and lower limits of the standard, the thickness division width, etc., it is convenient to connect a personal computer (not shown) to the multimeter 11d in advance and statistically analyze the detection results in the personal computer.
[0060]
Hereinafter, the operation of the classification device 1 will be described with reference to the flowchart shown in FIG.
First, the worker inputs a work W into the classification device 1 (step S1), and then touches the automatic start menu 37 on the title screen 20. Thereby, an instruction to start automatic operation is given from the operation panel 15 to the control unit 16.
Here, the loading of the workpiece W is performed by placing the cassette K storing the workpieces W having different plate thicknesses such as thin plates and thick plates on the transport device 23 of the loader loading unit 21.
[0061]
The control unit 16 acquires the workpiece W from the input cassette K with the automatic operation start signal from the operation panel 15 as an opportunity, and transfers the acquired workpiece W to the holding member 124 of the plate thickness measuring unit 11. The robot hand 6 is controlled.
[0062]
The movements of the robot hand 6, the workpiece W, and the plate thickness measuring unit 11 are as follows.
When the workpiece W gripped by the robot hand 6 is inserted between the pair of electrode plates 118, 119, the edge of the workpiece W is formed into V grooves 1211a, 1221a ... formed in the gripping portions 121, 122 of the holding member 124. Hold to hold by.
At this time, since the workpiece W is held by the robot hand 6, the workpiece W is in a fixed position. Based on this fixed position, the turntable 110a, the first LM guide 110b, and the second LM guide 110c move flexibly, and the workpiece W is fitted into the V-groove in a comfortable state without cracks or chips.
At this time, since the workpiece W is accurately positioned at a predetermined position between the pair of electrode plates 118 and 119, variation in the measurement result of the plate thickness is reduced, and the measurement accuracy can be improved.
After the workpiece W is positioned between the pair of electrode plates 118 and 119, the robot hand 6 releases the workpiece W. Then, it returns to the original position by the elastic body attached to the turntable 110a, the first LM guide 110b, and the second LM guide 110c, and starts measuring the plate thickness.
[0063]
Next, when the plate thickness measurement unit 11 acquires the workpiece W, the plate thickness measurement unit 11 measures the plate thickness of the workpiece W (step S2) and outputs the measurement result to the control unit 16.
[0064]
Next, the control unit 16 determines whether or not the plate thickness value output from the plate thickness measuring unit 11 is within the range of a given standard set in advance in the memory (step S3).
[0065]
Next, when the control unit 16 determines that the thickness value of the workpiece W is out of the standard (step S3; NO), the control unit 16 stores the workpiece W in the workpiece temporary storage place 7 (non-standard cassette). The robot hand 6 is controlled so as to be stored.
[0066]
On the other hand, if the control unit 16 determines that the thickness value of the workpiece W is within the standard (step S3; YES), the control unit 16 sends the workpiece W to the first stocker 31, the second stocker 32, and the third stocker 33. It is determined whether or not a cassette K which is a storage destination is arranged. That is, it is determined whether or not the cassette K is assigned to the classification corresponding to the plate thickness value among the classifications of the standard (step S5).
[0067]
Next, when it is determined that there is no storage location for the workpiece W (step S5; NO), the control unit 16 stores the workpiece W in the cassette K (stock cassette) disposed in the workpiece temporary storage location 7. The robot hand 6 is controlled (step S6).
As a result, the work W with relatively little demand is accumulated in the work temporary storage place 7. By supplying the cassette in the workpiece temporary storage place 7 to the loader loading unit 21 again, the excluded workpiece W can be classified with a smaller classification width.
[0068]
On the other hand, if the control unit 16 determines that there is a storage location of the workpiece W (step S5; YES), the cassette that is the storage location based on the detection results from the sensors 311a, 311b, 312a, 312b,. It is determined whether or not K is full (step S7).
[0069]
Next, when it is determined that the cassette K in which the workpiece W is to be stored is full (step S7; YES), the control unit 16 temporarily stops the operation of the classification apparatus 1 and displays the fact on the display unit. (Step S9).
[0070]
Here, the worker unloads the cassette K from the port 6 or the port 7, while disposing the empty cassette K at the position where the unloaded cassette K is disposed. Thereafter, the operator touches the preparation OK menu 38 on the title screen 20. Thereby, an operation restart instruction is given from the operation panel 15 to the control unit 16 (step S10).
[0071]
On the other hand, when the control unit 16 determines that the cassette K in which the workpiece W is to be stored is not full (step S7; NO), or when the operation restart instruction is given from the operation panel 15 in step S10, The robot hand 6 is controlled to store the workpiece W in the corresponding cassette K (step S11).
[0072]
〔Example〕
Next, a method for manufacturing an electronic device substrate using the classification apparatus 1 will be described.
In the following examples, a method for producing a glass substrate for an electronic device will be described by taking up a glass substrate for a photomask blank, but it goes without saying that the method is not limited to the substrate application, material, size, and the like.
[0073]
Forty-eight photomask blank glass substrates (size: 6 inches in length × size) in which the first polishing process was completed by a batch-type double-side polishing apparatus using a slurry in which abrasive grains having a relatively large particle size were suspended in water. (6 inches wide × 0.25 inches thick) (hereinafter referred to as a glass substrate) was stored in a cassette K and supplied to the loader loading portion 21 in the above-described classification device 1 for thickness division.
In addition, the setting of the thickness division in the classification apparatus 1 was 6.300 to 6.400 [mm].
[0074]
Of the glass substrates stored in the cassette K of the stocker of the unloader unit 3 and finished with the thickness division, the cassette K having a setting range of 6.300 to 6.400 [mm] was carried out.
A plurality of glass substrates stored in the unloaded cassette K were subjected to a final polishing process using a batch-type double-side polishing apparatus using a slurry in which ultrafine polishing abrasive grains were suspended in water.
[0075]
As a result, scratches and the like were not found on all glass substrate surfaces, and an ultra-flat and ultra-smooth glass substrate was obtained.
[0076]
[Comparative example]
On the other hand, in the polishing process of the glass substrate for photomask blank described above, when the first polishing process and the final polishing process were carried out without using a classification device and without dividing the plate thickness, the surface of several glass substrates A dent flaw was found on the surface, which resulted in poor surface roughness and flatness. Furthermore, the surface roughness of the obtained glass substrate had many variations. The production yield was reduced by 20% compared to the example.
[0077]
According to the classification device 1 described above, the following effects can be obtained.
(1) After step S11, since the workpieces W having approximate thicknesses are gathered in each of the cassettes K arranged in the first stocker 31, the second stocker 32, and the third stocker 33, each cassette K is placed in the first stocker 31. Unloading from one stocker 31, second stocker 32, and third stocker 33, all workpieces W stored in one or more cassettes K constituting one batch are put into a batch processing type polishing apparatus in a lump. If this is done, the icicles of all the workpieces W are generally aligned during double-side polishing. As a result, a sufficient polishing margin is secured for all the workpieces W, so that it is avoided that scratches and the like remain on these workpieces, and it is possible to avoid polishing each workpiece W more than necessary. . Thereby, a batch processing type polishing apparatus is effectively utilized. As a result, the yield can be improved and the cost of the glass substrate for electronic devices can be reduced.
[0078]
(2) Since the workpiece W supplied to the loader loading portion 21 is positioned between the pair of electrode plates 118 and 119 so as not to contact each electrode plate, the plate thickness of the workpiece W is detected without contact. Things are realized. Thereby, it is possible to avoid the workpiece W from being scratched.
[0079]
(3) Since the robot hand 6 is employed, the workpiece W can be accurately positioned when the workpiece W is transferred to the holding member 124.
When the workpiece W is transferred from the robot hand 6 to the holding member 124, the weight of the workpiece W is added to the plate thickness measuring unit 11. At that time, the plate thickness measuring unit 11 is freely rotated by the turntable 110a and is moved flexibly as a whole while being freely displaced by being guided by the first LM guide 110b and the second LM guide 110c. In the process, as shown in FIG. 17, the edge of the workpiece W is guided by V grooves 1211a, 1221a,... In this way, since the workpiece W can be accurately positioned (centered) at a predetermined position between the pair of electrode plates 118 and 119, variation in measurement results when the plate thickness of the same workpiece W is measured is reduced. Thus, the accuracy of the measurement result can be improved.
[0080]
(4) Since the plate thickness measuring part (gripping member) is returned to a predetermined reference position by the elastic body of the urging means, the workpiece W can be accurately transferred and gripped by the robot hand. Chipping can be prevented.
[0081]
(5) The operator uses the operation panel 15 to, for each of the plurality of cassettes K arranged in the first stocker 31, the second stocker 32, and the third stocker 33, the plate of the workpiece W stored in the cassette K. Since thickness ranges (classifications) can be assigned, workpieces W having different thicknesses for each cassette K can be aggregated, and workpieces W having the same range of thickness can be aggregated across a plurality of cassettes K. You can also.
[0082]
The preferred embodiment of the present invention has been described above, but the present invention is not limited to this. For example, the sorting apparatus 1 and a batch type polishing apparatus may be coupled so that the sorted batches of workpieces W are automatically loaded into the polishing apparatus. In this case, the operation of carrying out the cassette K from the first stocker 31, the second stocker 32, and the third stocker 33 can be omitted.
[0083]
The classification device 1 is preferably installed in a clean room. This prevents particles from adhering to the workpiece W, so that the measurement accuracy of the plate thickness measuring unit 11 can be further improved.
[0084]
【The invention's effect】
As described above, according to the present invention, it is possible to effectively utilize a batch processing type polishing apparatus in the production of a plate-like body that requires extremely high flatness and smoothness, such as a glass substrate for electronic devices. become. Moreover, the glass substrate for electronic devices which has high flatness and smoothness can be efficiently manufactured by using the classification apparatus of the present invention.
[Brief description of the drawings]
FIG. 1 is a plan view of a classification device according to an embodiment.
FIG. 2 is a front view of the classification device according to the embodiment.
FIG. 3 is a front view showing a main part of a plate thickness measuring unit in the classification device.
FIG. 4 is a schematic plan view for explaining the operation of a plate thickness measuring unit in the classification device.
FIG. 5 is a schematic diagram showing lines of electric force between electrode plates.
FIG. 6 is a block diagram showing an internal configuration of the classification device according to the embodiment.
FIG. 7 is a diagram schematically illustrating a display example of a touch panel on the operation panel.
FIG. 8 is a diagram schematically showing another display example of the touch panel on the operation panel.
FIG. 9 is a diagram schematically showing still another display example of the touch panel on the operation panel.
FIG. 10 is a diagram schematically showing still another display example of the touch panel on the operation panel.
FIG. 11 is a diagram schematically showing still another display example of the touch panel on the operation panel.
FIG. 12 is a diagram schematically showing still another display example of the touch panel on the operation panel.
FIG. 13 is a diagram schematically showing still another display example of the touch panel on the operation panel.
FIG. 14 is a diagram schematically illustrating still another display example of the touch panel on the operation panel.
FIG. 15 is a diagram schematically showing still another display example of the touch panel on the operation panel.
FIG. 16 is a flowchart for explaining the operation of the classification device according to the embodiment;
FIG. 17 is a diagram schematically illustrating a state in which a workpiece is positioned between a pair of electrode plates.
FIG. 18 is a schematic diagram for explaining a problem of the prior art.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Classification apparatus, 3 ... Unloader part (cassette arrangement | positioning part), 5 ... Transfer apparatus (storage mechanism), 6 ... Robot hand, 11 ... Plate thickness measurement part (plate thickness measurement means), 15 ... Control panel (input means) , 16 ... control section (control means), 21 ... loader loading section (supply section), 110a ... turntable, 110b ... first LM guide (guide member), 110c ... second LM guide (guide member), 121, 122 ... gripping Part (grip member), 124 ... holding member (positioning means), K ... cassette, W ... work (plate-like body).

Claims (3)

From a supply unit for supplying a glass substrate for electronic devices used for a photomask blank or a phase shift mask blank, a cassette arrangement unit for arranging a plurality of cassettes for storing a plurality of glass substrates for electronic devices, and the supply unit a plurality of the plate thickness measuring means, the glass substrate for an electronic device in which the plate thickness measured by the thickness measuring means, disposed on the cassette placement unit for measuring the thickness of a glass substrate for supplied the electronic device A storage mechanism for storing in any of the cassettes, and a control for controlling the storage mechanism to store the glass substrate for electronic device in each cassette according to the plate thickness based on the measurement result of the plate thickness measuring means. Means ,
The plate thickness measuring means is supplied from the supply unit and a capacitor having a pair of opposed electrode plates arranged in parallel to each other with a gap wider than the plate thickness of the electronic device glass substrate. Positioning means for positioning the glass substrate for electronic devices between the pair of electrode plates so as not to contact each electrode plate, and the glass substrate for electronic devices is positioned between the pair of electrode plates by the positioning means. Based on the comparison between the capacitance of the capacitor when given and a given reference capacitance, the thickness of the glass substrate for the electronic device is measured,
The positioning means includes a gripping member for gripping the glass substrate for electronic devices, and the gripping member is formed with a groove having a substantially V-shaped cross section to be fitted to an edge of the glass substrate for electronic devices. Consisting of
A robot hand that holds the electronic device glass substrate supplied from the supply unit and passes the glass substrate to the holding member of the positioning unit;
The plate thickness measuring means is configured to be freely turnable and displaceable from a reference position, and is provided with a biasing means for biasing to return to the reference position when swung and displaced from the reference position. , When the electronic device glass substrate is handed over to the gripping member by the robot hand, the electronic device glass substrate is fitted into the V-shaped groove of the gripping member and gripped, As a result, the electronic device glass substrate is positioned so that a minute gap is uniformly secured between the pair of electrode plates and the electronic device glass substrate. . 2. The classification apparatus according to claim 1, wherein an input means for assigning a range of a thickness of the glass substrate for electronic devices stored in the cassette for each of the plurality of cassettes arranged in the cassette arrangement unit. wherein the control means, the respective cassettes arranged in the cassette placement part, to control the storage mechanism to store the glass substrate for an electronic device having a thickness in the range assigned by the input means classification apparatus according to claim. In the manufacturing method of a glass substrate for electronic devices, which uses a batch processing type double-side polishing apparatus, and performs a precision polishing process over a plurality of stages to manufacture a glass substrate for electronic devices used for a photomask blank or a phase shift mask blank,
A plurality of glass substrates for electronic devices having different thicknesses that have undergone the previous polishing step are classified according to plate thickness by the classification device according to claim 1 or 2, and are classified within a set plate thickness range. A method for producing a glass substrate for an electronic device, comprising: obtaining a glass substrate for an electronic device having a desired high flatness and smoothness by polishing only the glass substrate for an electronic device in a subsequent polishing step. .

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