JP2004233054A - Substrate inspection device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inspect a pattern in resist on a substrate accurately and easily. <P>SOLUTION: When UV excitation light is applied to a sample 151, a resist pattern 23 formed by the resist of emulsion that is an organic compound generates fluorescence, while the mesh of a stainless wire 21 that is the lower layer of the resist pattern 23 is an inorganic compound and does not generate any fluorescence. Therefore, by observing the image of fluorescence, the pattern of the resist pattern 23 can be inspected accurately and easily. A substrate inspection device can be applied to, for example, a resist inspecting device. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate inspection apparatus and method, and more particularly, to a substrate inspection apparatus capable of accurately and easily inspecting a resist pattern on a substrate used for manufacturing a screen such as a television receiver and a monitor. And methods.
[0002]
[Prior art]
In one screen printing of stencil printing, a resist is formed according to a pattern to be printed on a mesh of silk, nylon, polyester, or the like stretched over a frame. As a result, a portion of the mesh from which the ink is extruded and a portion corresponding to the non-extruded pattern are formed, and an image corresponding to the pattern is printed. Recently, with the introduction of printing technology in the manufacturing process of electronic circuits, electronic components, micromachines, screens of television receivers, etc., the demand for precise fine pattern printing has increased, and the resolution, position, and dimensions have been increased. Improvements in accuracy, durability, etc. are being sought. Therefore, not only a mesh made of silk or synthetic resin or a resist pattern made of emulsion, but also a mesh made of metal wire such as stainless steel is used.
[0003]
The most important thing in screen printing is to accurately form a resist on a substrate. If there is a defect in a part of the resist on the substrate, the pattern cannot be accurately transferred, and a printed product based on the substrate becomes a defective product. Therefore, whether or not the resist on the substrate has a defect greatly affects the quality of printed matter. Therefore, in order to produce a good printed matter, it is necessary to inspect whether or not the resist on the substrate has a defect.
[0004]
As the inspection method, a substrate inspection method using white light or monochromatic light has been used.
[0005]
A substrate inspection method using white light or monochromatic light is a method of irradiating a resist on a substrate with white light and inspecting reflected light or transmitted light thereof (for example, see Patent Document 1).
[0006]
[Patent Document 1]
JP-A-1997-329423
[Problems to be solved by the invention]
However, in a substrate inspection method using white light or monochromatic light, when a resist on a substrate is irradiated with white light or monochromatic light, reflected light or transmitted light from the resist is included in reflected light or transmitted light due to the irradiation. Not only light but also reflected or transmitted light from the substrate itself is included, and in order to accurately inspect the resist for defects on the substrate, further image processing must be performed afterwards, making the process complicated. There was a problem of becoming.
[0008]
The present invention has been made in view of such a situation, and it is possible to accurately and easily inspect a resist pattern on a substrate used for manufacturing a screen such as a television receiver and a monitor. It is intended to be.
[0009]
[Means for Solving the Problems]
The substrate inspection apparatus of the present invention includes a generating unit that generates excitation light having a predetermined wavelength, an irradiation unit that irradiates the substrate with the excitation light generated by the generation unit, and a resist that emits the excitation light irradiated by the irradiation unit. Separating means for separating the fluorescence generated by the resist by being irradiated to the excitation light from the excitation light generated by the generating means, an image capturing means for capturing an image based on the fluorescent light separated by the separating means, and an image captured by the image capturing means And a display means for displaying.
[0010]
The generating means can generate ultraviolet light as excitation light.
[0011]
The substrate can be made of stainless steel.
[0012]
The substrate inspection method of the present invention generates excitation light having a predetermined wavelength, irradiates the generated excitation light onto a substrate, and irradiates the resist with the irradiated excitation light to generate fluorescence generated by the resist. It is characterized in that it separates from the excitation light to be irradiated, captures an image based on the separated fluorescence, and displays the captured image.
[0013]
In the substrate inspection apparatus and the substrate inspection method of the present invention, an image based on fluorescence emitted from a resist on the substrate by irradiating the substrate with excitation light having a predetermined wavelength is captured, and the captured image is Is displayed.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
FIG. 1 is a plan view of a stainless steel wire 21 mesh substrate 20 used for manufacturing a screen such as a television receiver or a monitor applied to the present invention.
[0016]
As shown in FIG. 1, the substrate 20 is formed by braiding the wires 21 in the vertical direction and the horizontal direction so as to intersect at right angles.
[0017]
2A to 2C show a partial cross-sectional configuration of the substrate in the manufacturing process of the substrate 20, and show cross-sectional views taken along line XX of FIG. FIG. 2A illustrates a cross-sectional configuration of the substrate 20. As shown in FIG. 2A, the substrate 20 is formed by alternately weaving the wires 21 in the vertical direction and the horizontal direction at right angles.
[0018]
After the substrate 20 shown in FIG. 2A is stretched on a substrate frame (not shown), a resist which is a photosensitive emulsion is uniformly applied thereon. The applied resist is dried, and a resist 22 (photosensitive film) is formed as shown in FIG. 2B.
[0019]
A resist mask (not shown) is brought into close contact with the formed resist 22 and is exposed by ultraviolet light, thereby forming a predetermined resist pattern 23 as shown in FIG. 2C.
[0020]
FIG. 3 shows a plan view of the substrate 20 on which the resist pattern 23 has been formed by the steps of FIGS. 2A to 2C.
[0021]
In the example shown in FIG. 3, the resist pattern 23 having a predetermined width is formed linearly at a predetermined pitch from the upper right direction to the lower left direction.
[0022]
FIG. 4 shows a configuration of a substrate inspection apparatus 90 of the present invention for inspecting the substrate 20 as shown in FIG.
[0023]
The board inspection device 90 of the present invention includes a detection unit 91, a control unit 92, and a display 93.
[0024]
The detection unit 91 irradiates the resist pattern 23 (resist 22) on the substrate 20 to be observed with excitation light having a predetermined wavelength, thereby receiving the fluorescent light emitted by the resist 22, and using the resist pattern based on the fluorescent light. The fluorescence image of 23 is output to the control unit 92. The configuration of the detection unit 91 and the principle of fluorescence observation will be described later with reference to FIG.
[0025]
The control unit 92 processes the image signal of the fluorescent image output from the detection unit 91 and outputs the processed image signal to a display 93 including a CRT (Cathode Ray Tube), an LCD (Liquid Crystal Display), and the like. Display.
[0026]
The control unit 92 includes an A / D converter 101, a CPU 102, a ROM 103, a RAM 104, an HDD (Hard Disc Drive) 105, and a bus 106 for connecting them.
[0027]
The A / D converter 101 converts the image signal output from the detection unit 91 from an analog signal to a digital signal.
[0028]
A CPU (Central Processing Unit) 102 controls a board inspection process according to a program stored in a ROM (Read Only Memory) 103 or a program loaded from a HDD 105 to a RAM (Random Access Memory) 104.
[0029]
A RAM 104 is a writable volatile memory that stores data and the like necessary for the CPU 102 to execute various processes, and is used to load an execution program of the CPU 102 and write work data of the execution program. It is. The ROM 103 is a read-only memory that stores a self-diagnosis / initialization program executed when the power of the substrate inspection apparatus 90 is turned on, a control code for hardware operation, and the like.
[0030]
FIG. 5 shows a configuration of the detection unit 91. The detection unit 91 includes a fluorescence microscope 121 and a video camera 161.
[0031]
The fluorescence microscope 121 irradiates the sample 151 formed of the substrate 20 with excitation light of a predetermined wavelength, thereby enabling observation of an image of fluorescence generated by the resist 22 on the sample 151. The video camera 161 receives the fluorescence transmitted through the absorption filter 135, captures a fluorescence image, converts the captured fluorescence image into an image signal, and outputs the image signal to the A / D converter 101.
[0032]
The fluorescence microscope 121 includes a light source 131, an excitation filter 132, a dichroic mirror 133, an objective lens 134, and an absorption filter 135.
[0033]
A light source 131 such as an ultra-high pressure mercury lamp or a xenon lamp generates light. The excitation filter 132 outputs light having a predetermined wavelength from light generated by the light source 131, for example, UV (Ultraviolet) excitation light having a wavelength of 360 nm to 380 nm, B (Blue) excitation light having a wavelength of 450 nm to 490 nm, or Only light in a specific wavelength range such as G (Green) excitation light having a wavelength of 520 nm to 550 nm is extracted.
[0034]
The dichroic mirror 133 arranged at an inclination of 45 degrees with respect to the optical axis separates the fluorescent light from the excitation light. That is, the dichroic mirror 133 reflects the excitation light incident from the excitation filter 132 and enters the objective lens 134. The dichroic mirror 133 reflects the excitation light reflected by the sample 151, transmits the fluorescence incident from the sample 151, and enters the absorption filter 135.
[0035]
The objective lens 134 converges and irradiates the sample 151 with the excitation light incident from the dichroic mirror 133. The resist pattern 23 (resist 22) of the specimen 151 to which the excitation light has been irradiated generates fluorescence having a predetermined wavelength.
[0036]
The objective lens 134 emits the fluorescent light incident from the sample 151 to the dichroic mirror 133.
[0037]
The absorption filter 135 selectively transmits only the fluorescence in a specific wavelength range from the light incident from the dichroic mirror 133 and emits it to the video camera 161.
[0038]
Next, the principle of fluorescence observation will be described.
[0039]
Some substances, when absorbing light energy, emit that energy again as light. This phenomenon is called photoluminescence (light emission), and fluorescence is one type of this photoluminescence. When a substance that performs photoluminescence is irradiated with excitation light such as X-rays, ultraviolet light, or visible light, molecules or atoms in the substance absorb light energy, and the electrons contained therein transition from the ground state to the excited state. I do. However, since the excited state is unstable, the electrons that have absorbed energy tend to return to the ground state immediately. Light emitted in this process is fluorescence.
[0040]
Further, there is a property that the wavelength of the observed fluorescence is longer than the wavelength of the irradiated excitation light. Therefore, depending on the target substance, for example, when UV (Ultraviolet) excitation light having a wavelength of 360 nm to 380 nm is used, the observed fluorescence wavelength is B (Blue) having a wavelength of 450 nm to 490 nm. It becomes.
[0041]
Generally, a fluorescent phenomenon is observed in most organic compounds, whereas a fluorescent phenomenon is hardly observed in an inorganic compound. In the case of an inorganic compound, only a specific compound such as a rare earth compound (for example, cerium) is used. No fluorescence phenomenon is observed.
[0042]
The resist 22 (resist pattern 23) is a photosensitive emulsion, that is, a photosensitive resin, and is an organic compound. Therefore, as described above, when the resist 22 is irradiated with ultraviolet light or the like, a fluorescent phenomenon is observed. On the other hand, the portion other than the resist 22 of the specimen 151 (substrate 20) is the stainless wire 21, that is, an inorganic compound, and does not emit fluorescence even when irradiated with ultraviolet light.
[0043]
As described above, when the sample 151 is irradiated with ultraviolet light or the like, only the resist 22 emits fluorescent light, and the other portions (wires 21) do not emit fluorescent light. The shape of the resist pattern 23 can be inspected accurately and easily without being affected by other parts.
[0044]
FIG. 6 shows a state in which the resist pattern 23 on the substrate 20 constituting the sample 151 is irradiated with excitation light.
[0045]
When UV (Ultraviolet) excitation light having a wavelength of 360 nm to 380 nm emitted from the excitation filter 132 is applied to the sample 151, the resist pattern 23 formed by the photosensitive emulsion resist 22 which is an organic compound generates fluorescence. On the other hand, the stainless steel wire 21 which is an inorganic compound does not emit fluorescence. Therefore, an image of only the fluorescence from the resist pattern 23 can be observed, so that the resist pattern 23 on the substrate 20 can be easily inspected.
[0046]
In this case, the fluorescence generated by the resist pattern 23 is, for example, B (Blue) light having a wavelength of 450 nm to 490 nm, and is irradiated with UV (Ultraviolet) having a wavelength of 360 nm to 380 nm as described above. It is longer than the wavelength of light. When the excitation light is B (Blue) light having a wavelength of 450 nm to 490 nm, for example, the fluorescence generated by the resist pattern 23 becomes G (Green) light having a wavelength of 520 nm to 550 nm, and the excitation light is emitted. In the case of G (Green) light having a wavelength of 520 nm to 550 nm, for example, the fluorescent light generated from the resist pattern 23 becomes R (RED) light having a wavelength of 670 nm to 770 nm.
[0047]
Next, the operation of the board inspection apparatus 90 according to the present invention will be described with reference to the flowchart of FIG.
[0048]
In step S1, the light source 131 generates light in a predetermined wavelength band. The excitation filter 132 is, for example, UV (Ultraviolet) excitation light having a wavelength of 360 nm to 380 nm, B (Blue) excitation light having a wavelength of 450 nm to 490 nm, or G having a wavelength of 520 nm to 550 nm from the incident light. (Green) Excitation light and the like are extracted and emitted. This excitation light is reflected by the dichroic mirror 133 and is irradiated on the sample 151 by the objective lens 134 in step S2. The resist pattern 23 on the specimen 151 (substrate 20) is excited by the excitation light to generate fluorescence. This fluorescence enters the dichroic mirror 133 via the objective lens 134. The dichroic mirror 133 separates the incident fluorescence from the excitation light in step S3. The absorption filter 135 extracts fluorescence having a predetermined wavelength from the fluorescence separated by the dichroic mirror 133 and emits the fluorescence to the video camera 161.
[0049]
In step S <b> 4, the video camera 161 captures an image of the incident fluorescence, converts the captured fluorescence image into an image signal, and outputs the image signal to the A / D converter 101. The A / D converter 101 converts the image signal of the resist fluorescent image output from the video camera 161 into a digital signal.
[0050]
In step S5, the CPU 102 outputs an image signal to the display 93 via the bus 105. As a result, an image of the resist pattern 23 based on the fluorescence is displayed on the display 93 as shown in FIG. 8, for example. As is apparent from a comparison between FIG. 8 and FIG. 3, the wire 21 is not displayed in the image of FIG.
[0051]
In step S <b> 6, the user checks whether or not the resist pattern 23 on the sample 151 (substrate 20) has a defect based on the fluorescent image on the screen substrate displayed on the display 93. Of course, this processing may be performed by causing the CPU 102 to execute image processing for comparing the shape of the obtained resist pattern 23 with a reference pattern.
[0052]
In step S7, the CPU 102 determines whether or not an instruction to save the fluorescent image of the resist pattern 23 in the HDD 105 has been input from the user. If it is determined in step S7 that a storage instruction has been input, the CPU 102 causes the HDD 105 to store the fluorescent image data in step S8. If it is not determined in step S7 that a save instruction has been input, the process of step S8 is skipped.
[0053]
In the above embodiment, the stainless steel wire 21 is used. However, if the substrate 20 is formed of a metal other than stainless steel as long as the material is made of an inorganic compound that does not generate fluorescence. Also, the present invention can be applied.
[0054]
【The invention's effect】
As described above, according to the present invention, the pattern of the resist on the substrate can be observed. In particular, according to the present invention, it is possible to accurately and easily inspect a resist pattern on a substrate. This makes it possible to efficiently inspect for defects in the resist on the substrate, and to suppress the occurrence of product defects due to defects in the resist on the substrate.
[Brief description of the drawings]
FIG. 1 is a plan view showing the configuration of a stainless steel wire mesh substrate.
FIG. 2 is a cross-sectional view showing a configuration of a part of the substrate in a process of manufacturing a substrate of a stainless steel wire mesh.
FIG. 3 is a plan view showing a configuration of a substrate on which a resist pattern is formed.
FIG. 4 is a block diagram illustrating a configuration of a substrate inspection apparatus according to the present invention.
FIG. 5 is a block diagram illustrating a configuration of a detection unit in FIG. 4;
FIG. 6 is a diagram illustrating a state where excitation light is irradiated onto a substrate.
FIG. 7 is a flowchart illustrating the operation of the board inspection apparatus according to the present invention.
FIG. 8 is a diagram illustrating an example of a fluorescent image.
[Explanation of symbols]
REFERENCE SIGNS LIST 20 substrate 21 wire 22 resist 23 resist pattern 90 substrate inspection device 91 detection unit 92 control unit 93 display 101 A / D converter 102 CPU
103 ROM
104 RAM
105 HDD
106 Bus 131 Light source 132 Excitation filter 133 Dichroic mirror 134 Objective lens 135 Absorption filter 151 Sample 161 Video camera

Claims (4)

In a substrate inspection apparatus for inspecting a screen manufacturing substrate on which a resist pattern is formed,
Generating means for generating excitation light having a predetermined wavelength,
Irradiating means for irradiating the substrate with the excitation light generated by the generating means,
Separating means for separating the fluorescence generated by the resist from the excitation light generated by the generating means, by irradiating the resist with the exciting light irradiated by the irradiating means,
Imaging means for capturing an image based on the fluorescence separated by the separation means,
A substrate inspection apparatus comprising: a display unit that displays the image captured by the imaging unit. The substrate inspection apparatus according to claim 1, wherein the generation unit generates ultraviolet light as the excitation light. The said board | substrate is comprised by stainless steel, The board | substrate inspection apparatus of Claim 1 characterized by the above-mentioned. In a substrate inspection method of a substrate inspection apparatus that inspects a substrate for screen manufacturing on which a pattern of a resist is formed,
Generating excitation light having a predetermined wavelength;
Irradiating the generated excitation light onto the substrate,
Irradiated excitation light separates the fluorescent light generated by the resist by being irradiated on the resist from the irradiated excitation light,
Capturing an image based on the separated fluorescence,
A substrate inspection method, comprising displaying the captured image.

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