JP2014130068A - Resist pattern measuring device, resist pattern measuring method, and management method for concentration of resist developing solution - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measuring device capable of accurately measuring a plurality of resist patterns formed on a glass substrate in a standing state.SOLUTION: The device for measuring a resist pattern measures a plurality of resist patterns 301 formed on a glass substrate 100 in a standing state. The device includes: cameras 20A, 20B, 20C having an autofocusing mechanism for taking pictures of the plurality of resist patterns 301; and calculation means for calculating a line width of the plurality of resist patterns on the basis of the images of the plurality of resist patterns taken by the cameras.

Description

  The present invention relates to a resist pattern measuring device, a resist pattern measuring method, and a resist developer concentration management method.

  Photolithographic methods are used to form patterned layers such as electrodes on flat panel displays (hereinafter referred to as FPD) such as liquid crystal displays, plasma displays, electroluminescence displays, and field emission displays, and glass substrates of solar cells. (For example, refer to Patent Document 1).

  In recent years, with the spread of large-screen plasma televisions and the like, pattern layers are often formed on a large-sized glass substrate by photolithography. In such a case, in order to reduce the work space, the glass substrate may be conveyed in an upright state to form a pattern layer on the main surface of the glass substrate.

  In the patterning step of forming the pattern layer on the main surface of the glass substrate, the line width or gap width of the resist pattern immediately after development with the resist developer is measured in order to improve the dimensional accuracy of the pattern layer. Then, the measurement result is analyzed to review various conditions (for example, developer concentration) in the patterning process.

  In addition, when measuring the line width or gap width of a resist pattern formed on a large-sized glass substrate, it is preferable to perform so-called on-line measurement from the viewpoint of manufacturing efficiency. On-line measurement is to measure the line width or gap width of a resist pattern formed on a glass substrate during the patterning process.

  Conventionally, in the on-line measurement of the line width or gap width of a resist pattern formed on a glass substrate, a plurality of resist patterns on the glass substrate are imaged by an imaging device such as a CCD camera or an area camera. A method of calculating the line width or gap width of a resist pattern by image processing with a computer has been employed.

JP 2004-240095 A

  As described above, in recent years, there has been an increasing demand for thinner glass substrates due to the reduction in thickness and weight of large-screen televisions. However, when the glass substrate is conveyed in an upright state, the thinner the glass substrate is, the more easily the glass substrate is warped and bent, and the glass substrate is more likely to vibrate. If the glass substrate is warped, bent, vibrated, or the like, the imaging apparatus is out of focus, the captured image becomes unclear, and the measurement accuracy of the line width or gap width of the resist pattern is lowered.

  The present invention has been made in view of the above circumstances, and an object thereof is to accurately measure a plurality of resist patterns formed on a standing glass substrate.

  In order to achieve the above object, a first invention is a resist pattern measuring apparatus for measuring a plurality of resist patterns formed on a standing glass substrate, and an autofocus mechanism for imaging the plurality of resist patterns. And a calculating means for calculating at least one of a line width of the plurality of resist patterns and a gap width of the plurality of resist patterns based on images captured by the plurality of resist patterns by the imaging device. Prepare.

  According to the first invention, by using the imaging device with an autofocus mechanism, a clear captured image of a resist pattern can be obtained even if the standing glass substrate is bent, warped, vibrated, or the like. Therefore, the line width and / or gap width of the resist pattern can be measured with high accuracy.

  In one embodiment, the resist pattern measurement device includes a plurality of the imaging devices, and each of the plurality of imaging devices is parallel to a main surface of the glass substrate and perpendicular to a conveyance direction of the glass substrate. Be placed.

  In this case, the resist pattern is imaged by each of the plurality of imaging devices, and among the plurality of measurement values calculated from the obtained plurality of captured images, extreme measurement values caused by scratches, dirt, chips, etc. on the resist pattern are obtained. By excluding, the line width and / or gap width of the resist pattern can be measured with higher accuracy.

  In one embodiment, the resist pattern measurement device includes a focusing unit that independently controls an autofocus mechanism provided in each of the plurality of imaging devices.

  In this case, even when local warping, bending, vibration, or the like is generated on the glass substrate, each of the plurality of imaging devices can obtain a captured image of a clear resist pattern. Therefore, the line width and / or gap width of the resist pattern can be measured with higher accuracy.

  In one embodiment, the imaging apparatus has an objective lens and measures the distance between the objective lens and the glass substrate, and an imaging apparatus main body arranged with the objective lens facing the glass substrate. Measuring means and a drive mechanism for moving the imaging device main body in a direction in which the objective lens approaches and separates from the glass substrate.

  In this case, by moving the imaging device main body and performing focusing, it is possible to prevent the measurement visual field from changing, and even if the glass substrate is greatly warped, deformed, bent, etc., a clear resist pattern is captured. Can be obtained. In other words, when the imaging device main body is fixed and the lens is moved and focused, the measurement visual field may change, but the imaging device main body is moved and focused to suppress changes in the measurement visual field. be able to. Therefore, the line width and / or gap width of the resist pattern can be measured with higher accuracy.

  In one embodiment, the imaging apparatus includes a light emitting unit that emits strobe light toward the glass substrate.

  In this case, the flow of the captured image by the imaging device can be suppressed. Therefore, the line width and / or gap width of the resist pattern can be measured with higher accuracy.

  The second invention is a resist pattern measurement method for measuring a plurality of resist patterns formed on an upright glass substrate, and an imaging device with an autofocus mechanism for imaging the plurality of resist patterns is prepared. A preparatory step, an imaging step of imaging the plurality of resist patterns by the imaging device, a line width of the plurality of resist patterns and the plurality of resist patterns based on captured images of the plurality of resist patterns by the imaging device A calculation step of calculating at least one of the gap widths.

  According to the second invention, by using an imaging device with an autofocus mechanism, it is possible to obtain a clear captured image of a resist pattern even if the glass substrate in a standing state is bent, warped, vibrated, or the like. Therefore, the line width and / or gap width of the resist pattern can be measured with high accuracy.

  According to a third aspect of the present invention, there is provided a resist developer concentration management method for forming a plurality of resist patterns on an upright glass substrate, wherein an imaging device with an autofocus mechanism for imaging the plurality of resist patterns is provided. A preparatory step to prepare; an imaging step of imaging the plurality of resist patterns by the imaging device; and line widths of the plurality of resist patterns and the plurality of resists based on images captured by the plurality of resist patterns by the imaging device Based on the calculation step of calculating at least one of the gap widths of the pattern, and at least one of the line width of the plurality of resist patterns and the gap width of the plurality of resist patterns, the concentration of the resist developer is determined. And a developer concentration adjusting step to adjust.

  According to the third invention, even if the temperature and humidity in the patterning step, the temperature of the resist developer, etc. affect the line width of the resist pattern in a complex manner, the line width and / or gap width of the resist pattern Measurement with high accuracy can be performed, and the line width of the resist pattern can be corrected by adjusting the concentration of the resist developer. As a result, a glass substrate with stable quality can be manufactured.

  According to the present invention, the line width or gap width of a resist pattern formed in the middle of a patterning process can be accurately measured.

1 is a schematic diagram illustrating a schematic configuration of a resist pattern measuring device, a developing device, and a developer supply device according to an embodiment of the present invention. It is a schematic diagram which shows schematic structure of the camera and glass substrate which are used for the resist pattern measuring apparatus shown by FIG. It is explanatory drawing of the patterning process which forms a pattern layer on a glass substrate by the photolithographic method.

  Embodiments according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing a schematic configuration of a resist pattern measuring device, a developing device, and a developer supply device according to an embodiment of the present invention.

  The resist pattern measuring device 10 measures a plurality of resist patterns formed on the standing glass substrate 100.

  The resist pattern measuring device 10 is installed between a developing device 40 that develops a resist pattern on the glass substrate 100 and an etching facility (not shown) that performs etching on the substrate 100 on which the resist pattern has been developed.

  The glass substrate 100 is transported in a horizontal direction parallel to the main surface 100a in an upright state by a transport device (not shown).

  The resist pattern measurement device 10 includes three cameras 20A, 20B, and 20C and a control device 30. The cameras 20A, 20B, and 20C function as the imaging device of the present invention. Details of the cameras 20A, 20B, 20C and the control device 30 will be described later with reference to FIG.

  The developing device 40 supplies a resist developer to the resist layer formed on the main surface 100a of the glass substrate 100 transported in the X direction to develop the resist pattern.

  The developer supply device 50 supplies a resist developer to the developing device 40. The developer supply device 50 includes a developer tank 51, a stock solution tank 52, a first valve 53, a diluent tank 54, and a second valve 55.

  The developer tank 51 accommodates a resist developer prepared by preparing a stock solution and a diluted solution of a resist developer. The stock solution tank 52 stores a stock solution of a resist developer. The first valve 53 is installed in a pipe line that connects the developer tank 51 and the stock solution tank 52 in communication. By adjusting the opening degree of the first valve 53, the amount of the stock solution supplied from the stock solution tank 52 to the developer tank 51 can be adjusted. The diluent tank 54 stores the diluent. The second valve 55 is installed in a pipe line that connects the developer tank 51 and the diluent tank 54 to each other. By adjusting the opening of the second valve 55, the amount of the diluent supplied from the diluent tank 54 to the developer tank 51 can be adjusted. By adjusting the opening degree of the first valve 53 and the opening degree of the second valve 55, the mixing ratio of the stock solution and the diluting solution can be changed, and the concentration of the resist developer in the developer tank 51 can be adjusted. it can.

  The material of the resist developer is not particularly limited as long as it has excellent resist layer solubility. In addition to generally used organic alkali developers, inorganic alkali developers can also be used.

  The resist pattern measuring device 10 measures the line width of the resist pattern on the glass substrate 100 immediately after being developed by the developing device 40 on-line. The operator looks at the measurement result by the resist pattern measuring device 10 and operates the developer supply device 50 to adjust the concentration of the resist developer supplied to the developing device 40.

  FIG. 2 is a schematic diagram showing a schematic configuration of the cameras 20A, 20B, and 20C and the glass substrate 100 used in the resist pattern measuring apparatus 10 shown in FIG. Each of the cameras 20A, 20B, and 20C functions as an imaging device of the present invention.

  The line width W1 of the resist pattern 301 and the width W2 of the gap 302 measured by the resist pattern measuring apparatus 10 (see FIG. 1) are not particularly limited. For example, the width W1 is 100 μm to 500 μm, and the width W2 is 80 μm to 100 μm.

  The camera 20A is constituted by, for example, a CCD camera, and includes a camera body 21 as an imaging apparatus body, an objective lens 22 mounted on the front surface thereof, a drive mechanism 23 for moving the camera body 21, and a distance sensor as a distance measuring unit. 28 and a strobe light emitter 29 as a light emitting means. The drive mechanism 23 includes a stage 24, a ball screw 25, a bearing 26, and a stepping motor 27.

  The camera body 21 is fixedly supported on the stage 24 with the objective lens 22 facing the main surface 100 a of the glass substrate 100. The stage 24 is provided with an optical axis A.A. It is guided so as to reciprocate in the direction along X.

  The ball screw 25 is supported by a bearing 26 and screwed into a screw hole (not shown) screwed to the stage 24. When the stepping motor 27 is driven, the ball screw 25 rotates around the axis and the stage 24 moves, and the camera body 21 approaches or separates from the main surface 100 a of the glass substrate 100.

  The distance sensor 28 has an optical axis A. Sensor light is emitted in the direction along X, and the distance between the main surface 101a of the glass substrate 100 and the objective lens 22 is measured. The distance sensor 28 and the drive mechanism 23 function as an autofocus mechanism of the present invention.

  The strobe light emitter 29 emits light toward the main surface 100 a of the glass substrate 100. The cameras 20A, 20B, and 20C are always photographing the resist pattern 301, and the glass substrate 100 is moving. Therefore, when the line width of the resist pattern 301 becomes high definition, the image of the resist pattern 301 captured by the cameras 20A, 20B, and 20C may flow. Therefore, the strobe light emitter 29 is caused to emit light. As a result, the image of the resist pattern 301 can be captured as a still image.

  Since the configuration of the camera 20B and the camera 20C is the same as that of the camera 20A, description thereof is omitted. The camera 20A shoots the uppermost shooting area among the shooting areas obtained by dividing the main surface 100a of the glass substrate 100 in the vertical direction, the camera 20B shoots the middle shooting area, and the camera 20C shoots the lowermost shooting area. Shoot the area.

  The description of the configuration of the resist pattern measuring apparatus 10 will be continued with reference to FIGS. 1 and 2. The control device 30 is configured by a microcomputer including a CPU, a ROM, a RAM, and the like. The CPU executes various processes according to programs stored in the ROM. Each of the image processing means 31, the arithmetic processing means 32, and the focusing means 33 is configured by a program stored in the ROM.

  The image processing means 31 performs image processing on the image of the resist pattern 301 captured by the cameras 20A, 20B, and 20C, and creates an image from which the line width of the resist pattern 301 can be calculated.

  The arithmetic processing unit 32 calculates the line width of the resist pattern 301 from the image produced by the image processing unit 31 according to a predetermined algorithm. The image processing means 31 and the arithmetic processing means 32 function as calculation means of the present invention.

  The focusing unit 33 controls the stepping motor 27 based on the measurement value of the distance sensor 28 to focus on the resist pattern 301 of the cameras 20A, 20B, and 20C.

  Next, the patterning process will be described. FIG. 3 is an explanatory diagram of a patterning process for forming a pattern layer on a glass substrate by photolithography.

  First, as shown in FIG. 3A, a thin film 200 made of a conductive metal (for example, ITO) is formed on the main surface 100a of the glass substrate 100 by sputtering or the like. Next, as shown in FIG. 3B, a photoresist (photosensitive resin) is applied on the thin film 200 to form a resist layer 300. Next, as illustrated in FIG. 3C, the resist layer 300 is covered with a photomask 400 and irradiated with light (for example, ultraviolet rays), and a predetermined pattern 401 formed on the photomask 400 is formed on the resist layer 300. Transcript. Next, a resist developer is supplied to the resist layer 300. As a result, as shown in FIG. 3D, the exposed portion of the resist layer 300 is removed, and a plurality of resist patterns 301 are formed on the thin film 200. Next, as shown in FIG. 3E, etching is performed to remove unnecessary portions of the thin film 200. When the resist pattern 301 is removed, a pattern layer 201 having a predetermined shape appears on the glass substrate 100 as shown in FIG.

  Next, a method for measuring the line width of the resist pattern 301 and a method for managing the concentration of the resist developer will be described with reference to FIGS.

  As shown in FIG. 1, three cameras 20 </ b> A, 20 </ b> B, and 20 </ b> C are provided on the downstream side of the developing device 40 along a direction parallel to the main surface 100 a of the glass substrate 100 and orthogonal to the conveyance direction X of the glass substrate 100. Install at intervals (preparation process).

  The glass substrate 100 is conveyed in a horizontal direction parallel to the main surface 100 a in the standing state and reaches the developing device 40. Then, the developing device 40 supplies a resist developer to the resist layer 300 (see FIG. 3C). A resist pattern 301 (see FIG. 3D) is formed by supplying the resist developer to the resist layer 300 by the developing device 40.

  As shown in FIG. 2, the resist pattern 301 formed on the glass substrate 100 is simultaneously imaged by the cameras 20A, 20B, and 20C. At that time, the distance sensor 28 provided in the cameras 20A, 20B, and 20C measures the distance between the main surface 100a of the glass substrate 100 and the objective lens 22, and the focusing means 33 (see FIG. 1) based on the measured value. Drives the stepping motor 27 to focus the cameras 20A, 20B, and 20C on the resist pattern 301.

  Simultaneously with focusing, the strobe light emitter 29 emits light for a predetermined time. The image of the resist pattern 301 during the light emission of the strobe light emitter 29 is substantially a still image. The light emission time of the strobe light emitter 29 is set to 1 μsec to 20 μsec, for example, when the conveyance speed of the glass substrate 100 is 0.1 m / sec to 0.5 m / sec (imaging process).

  Images of the resist pattern 301 captured by the cameras 20A, 20B, and 20C are input to the control device 30 (see FIG. 1). The image processing unit 31 performs image processing on the images input from the cameras 20A, 20B, and 20C, and creates an image from which the line width of the resist pattern 301 can be calculated.

  Then, the arithmetic processing unit 32 calculates the line width of the resist pattern 301 from the image of the resist pattern 301 subjected to the image processing by the image processing unit 31 according to a predetermined algorithm (calculation step). The line width of the resist pattern 301 calculated by the arithmetic processing means 32 is displayed on a display (not shown) of the control device 30.

  The operator compares the line width of the resist pattern 301 displayed on the display with a preset target value, and examines whether or not it is necessary to adjust the concentration of the resist developer. When it is necessary to adjust the concentration of the resist developer, the opening degree of the first valve 53 and / or the second valve 55 of the developer supply device 50 is adjusted to adjust the concentration of the resist developer in the developer tank 51. Adjust (developer concentration adjustment step).

  According to the resist pattern measuring apparatus 10, since the resist pattern 301 is imaged using the cameras 20A, 20B, and 20C with an autofocus mechanism, the cameras 20A, 20B can be used even if warping, bending, vibration, or the like occurs in the glass substrate 100. , 20C can be accurately focused. Further, since the resist pattern 301 is imaged using the strobe light emitter 29, the captured image does not flow even if the resist pattern 301 becomes high definition. Therefore, the line width of the resist pattern 301 can be measured with high accuracy.

  In addition, even when the temperature and humidity in the patterning step, the temperature of the resist developer, and the like affect the line width of the resist pattern 301 in a complex manner, the line width and / or gap width of the resist pattern 301 can be accurately measured. In addition, the line width of the resist pattern 301 can be corrected by adjusting the concentration of the resist developer. As a result, the glass substrate 100 with stable quality can be manufactured.

  In addition, since the cameras 20A, 20B, and 20C simultaneously capture the resist pattern 301, the measured values of the cameras 20A, 20B, and 20C are compared, resulting in extreme measured values (for example, due to scratches, chips, or dirt on the resist pattern 301). Can be excluded). Therefore, the resist pattern 301 can be measured with high accuracy.

  In addition, by individually controlling each of the three cameras 20A, 20B, and 20C, even when local deflection or warpage occurs in the glass substrate 100, the three cameras 20A, 20B, and 20C are in focus. Can be accurately combined. Therefore, the resist pattern 301 can be measured with high accuracy.

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

  For example, in the above-described embodiment, the line width of the resist pattern is calculated based on the captured image of the resist pattern captured by the imaging unit. However, the gap width of the resist pattern is calculated based on the captured image of the resist pattern captured by the imaging unit. May be calculated. Further, the line width and gap width of the resist pattern may be calculated based on the captured image of the resist pattern imaged by the imaging means.

  In the above embodiment, the resist pattern line width is measured, and the concentration of the resist developer is adjusted based on the measured value. However, the resist pattern gap width is measured, and the resist pattern is measured based on the measured value. You may adjust the density | concentration of a developing solution. Alternatively, each of the line width and gap width of the resist pattern may be measured, and the concentration of the resist developer may be adjusted based on the measured values.

  Moreover, in the said embodiment, although the CCD camera is used as an imaging device, you may use another imaging device (for example, area camera and CMOS).

  Moreover, in the said embodiment, although the 3 imaging devices are used, 4 or more imaging devices may be sufficient as an imaging device.

  In the above embodiment, the imaging apparatus main body is moved and focused. However, the imaging apparatus main body may be fixed and the optical system included in the imaging apparatus may be moved and focused.

  In the above embodiment, the distance measuring unit measures the distance between the main surface of the glass substrate and the objective lens, but the distance measuring unit is a member (for example, a resist pattern or a thin film) on the main surface of the glass substrate. You may make it measure the distance with an objective lens.

  In the above embodiment, the resist developer concentration is manually adjusted by an operator. However, the resist developer concentration may be adjusted automatically by a control device.

  In the above embodiment, the stepping motor is used to move the imaging apparatus main body. However, a servo motor can be used instead of the stepping motor.

  In addition, various modifications can be made to the above embodiment without departing from the gist of the present invention.

10 resist pattern measuring device 20A, 20B, 20C camera (imaging device)
21 Camera body (Imaging device body)
22 Objective lens 23 Drive mechanism (autofocus mechanism)
24 stage 25 ball screw 26 bearing 27 stepping motor 28 distance sensor (autofocus mechanism, distance measuring means)
29 Strobe light emitter (light emission means)
30 Control device 31 Image processing means (calculation means)
32 Arithmetic processing means (calculation means)
40 Developing Device 50 Developer Supply Device 51 Developer Solution Tank 52 Stock Solution Tank 53 First Valve 54 Dilution Solution Tank 55 Second Valve 100 Glass Substrate 200 Thin Film 201 Pattern Layer 300 Resist Layer 301 Resist Pattern 400 Photomask

Claims (7)

A resist pattern measurement device that measures a plurality of resist patterns formed on a standing glass substrate,
An imaging device with an autofocus mechanism for imaging the plurality of resist patterns;
A resist pattern measurement comprising: a calculating unit that calculates at least one of a line width of the plurality of resist patterns and a gap width of the plurality of resist patterns based on images captured of the plurality of resist patterns by the imaging device. apparatus.
A plurality of the imaging devices;
2. The resist pattern measurement device according to claim 1, wherein each of the plurality of imaging devices is arranged along a direction parallel to a main surface of the glass substrate and perpendicular to a conveyance direction of the glass substrate.
The resist pattern measurement apparatus according to claim 2, further comprising a focusing unit that independently controls an autofocus mechanism provided in each of the plurality of imaging apparatuses.
The imaging device
An imaging apparatus main body having an objective lens and being arranged with the objective lens facing the glass substrate;
Distance measuring means for measuring the distance between the objective lens and the glass substrate;
The resist pattern measuring device according to claim 1, further comprising: a drive mechanism that moves the imaging device main body in a direction in which the objective lens approaches and separates from the glass substrate.
The resist pattern measurement device according to claim 1, wherein the imaging device includes a light emitting unit that emits strobe light toward the glass substrate.
A resist pattern measurement method for measuring a plurality of resist patterns formed on a standing glass substrate,
A preparation step of preparing an imaging device with an autofocus mechanism that images the plurality of resist patterns;
An imaging step of imaging the plurality of resist patterns by the imaging device;
A calculation step of calculating at least one of a line width of the plurality of resist patterns and a gap width of the plurality of resist patterns based on images captured by the plurality of resist patterns by the imaging device;
A resist pattern measuring method.
A resist developer concentration management method for forming a plurality of resist patterns on a standing glass substrate,
A preparation step of preparing an imaging device with an autofocus mechanism that images the plurality of resist patterns;
An imaging step of imaging the plurality of resist patterns by the imaging device;
A calculation step of calculating at least one of a line width of the plurality of resist patterns and a gap width of the plurality of resist patterns based on images captured by the plurality of resist patterns by the imaging device;
A developer concentration adjusting step of adjusting a concentration of the resist developer based on at least one of a line width of the plurality of resist patterns and a gap width of the plurality of resist patterns. Concentration management method.

Images