CN1841012A

CN1841012A - Unevenness detection device and unevenness detection method

Info

Publication number: CN1841012A
Application number: CN 200610068377
Authority: CN
Inventors: 上田邦夫; 吉原一博; 谷口和隆
Original assignee: Dainippon Screen Manufacturing Co Ltd
Current assignee: Skilling Group; Dainippon Screen Manufacturing Co Ltd
Priority date: 2005-03-31
Filing date: 2006-03-30
Publication date: 2006-10-04
Anticipated expiration: 2026-03-30
Also published as: JP2006284211A; CN100427877C

Abstract

There provides an unevenness inspection device. The unevenness inspection device includes a stage holding a substrate; a light emission part emitting a linear light toward an upper surface of the substrate on which a film is formed: a photodetection part receiving the reflected light from the substrate; a wavelength band switching mechanism disposed between the substrate and the photodetection part and switching the wavelength band of the light; a moving mechanism moving the stage; and an inspection part inspecting the film thickness unevenness on the basis of the intensity distribution of the received light. In the unevenness inspection device, the incident angle [theta]1 of the light incident from the light emission part on the substrate with respect to the upper surface is made 60[deg.]. Thus, the range of the film thickness permitting precise unevenness detection is enlarged, and the width of the low sensitivity region which is the region in the vicinity of the maximum point of the reflectance with respect to the film thickness is prevented from broadening. As a result, the variation width is prevented from being included in the low-sensitivity region, and the very little film thickness unevenness is precisely detected.

Description

Irregular testing fixture and irregular inspection method

Technical field

The present invention relates to a kind of inspection irregular technology of the thickness of formed film on substrate.

Background technology

All the time, when checking on the interarea of (following only be called " substrates ") such as glass substrate that display device is used and semiconductor substrates film such as formed etchant resist, to be mapped on the film from the illumination of light source, and be used to check the irregular of thickness from the reflected light of film with through the interference of light of light.

In the irregular inspection of this thickness, when having used monochromatic source such as sodium vapor lamp, because the thickness of film and refractive index and can not obtain sufficient sensitivity (that is, can not clearly represent produce interference fringe) by the interference of light.Therefore, in by the visual inspection of carrying out, change the incident angle of light, carry out irregular detection reliably by the inclination substrate.In addition, though the processing that also has pair substrate to shine the light of a plurality of wavelength simultaneously, owing to the interference fringe corresponding with each wavelength occurs simultaneously, so the possibility that exists sensitivity on the whole to descend.

Following technology is disclosed in TOHKEMY 2002-267416 communique, carrying out being tested in the surface defect inspection apparatus of the defect inspection on the surface, make restriction be tested film characteristics (material, refractive index, thickness, reflectivity etc.) on the surface from a cooperation in a plurality of narrow band pass filters of the catoptrical wave band of being tested body, and be inserted on the light path, thereby check with appropriate wave band.In addition, the characteristic that also discloses the cooperation film changes technology from the angle (being that illumination light is to being tested the incident angle of body) of the Lighting Division of body irradiates light to quilt that test.

But, in by the visual inspection of carrying out, observe by the inclination substrate and to make the interference fringe sharpening, this can carry out with comparalive ease, but, shown in the surface defect inspection apparatus of TOHKEMY 2002-267416 communique, taking from the reflected light of being tested body and obtaining according to the brightness value of each pixel value and represent in the device of the image that thickness is irregular, at the change Lighting Division when being tested the angle of body, the angle that receives catoptrical linear sensor camera also needs to cooperate the incident angle of illumination light, adjusts accurately.Therefore, it is complicated that the structure of device becomes, and the operation when checking becomes miscellaneous.

In addition, about from the light of Lighting Division to being tested the incident angle of body, there is suitable angle respectively in the characteristic irregular according to the thickness that will detect, and be still, in TOHKEMY 2002-267416 communique, open whatever for concrete incident angle.

Summary of the invention

Fundamental purpose of the present invention is to be formed on towards inspection the irregular irregular testing fixture of thickness of the film on the substrate, and it is irregular that precision detects small thickness than the highland.In addition, it is irregular that its purpose also is to detect reliably the bigger thickness of mobility scale.

Irregular testing fixture has: maintaining part, and it keeps substrate; The light injection part, it penetrates with respect to aforesaid substrate and is formed with the interarea of film of photopermeability with the light of 50 °～65 ° incident angle incident; Sensor, it is received in the light of the specific band after above-mentioned interarea reflection of aforesaid substrate, and the light intensity of obtaining from the above-mentioned specific band of above-mentioned interarea distributes; The wave band switching device shifter, it switches above-mentioned specific wave band between different mutually a plurality of wave bands.According to the present invention, can precision to detect small thickness than the highland irregular.

In one of the present invention preferred embodiment, in irregular testing fixture, above-mentioned smooth injection part penetrates the light of the light that contains above-mentioned a plurality of wave bands; Above-mentioned wave band switching device shifter has: a plurality of optical filters, and it optionally makes the light of above-mentioned a plurality of wave bands see through respectively; The optical filter switching mechanism, it switches to an optical filter on being configured in from above-mentioned smooth injection part to the light path of above-mentioned sensor in above-mentioned a plurality of optical filters other optical filter.Thus, can easily switch the wave band of the light of acceptance.

The present invention another preferred embodiment in, in irregular testing fixture, also have: the first optical filter leaning device, it changes in above-mentioned a plurality of optical filter first optical filter with respect to the inclination angle of above-mentioned light path; The second optical filter leaning device, it is different from above-mentioned first optical filter and changes in above-mentioned a plurality of optical filter second optical filter individually with respect to the inclination angle of above-mentioned light path; Travel mechanism, it with respect to above-mentioned smooth injection part and the sensor, relatively moves above-mentioned maintaining part on the moving direction of the regulation of the above-mentioned interarea of aforesaid substrate, above-mentioned smooth injection part has: light source, and its ejaculation contains the light of the light of above-mentioned a plurality of wave bands; Optical system, it will be transformed to from the light of above-mentioned light source along above-mentioned interarea and perpendicular to the Line of light of above-mentioned moving direction, and the above-mentioned interarea that leads, the sensor is a linear sensor, the mobile light intensity distribution that obtains synchronously and repeatedly from the above-mentioned specific wave band of the irradiation area of above-mentioned Line of light on aforesaid substrate of this linear sensor and above-mentioned maintaining part.Thus, can precision adjust the wave band that sees through of optical filter than the highland.

In other embodiments of the present invention, irregular testing fixture also has polariscope, on this polariscope is configured in from above-mentioned smooth injection part to the light path of above-mentioned sensor, and the S polarized light with respect to above-mentioned film is seen through.

In one aspect of the invention, irregular testing fixture has: maintaining part, and it keeps substrate; The light injection part, it penetrates with respect to aforesaid substrate and is formed with the interarea of film of photopermeability with the light of 10 °～40 ° incident angle incident; Sensor, it is received in the light of the specific band after above-mentioned interarea reflection of aforesaid substrate, and the light intensity of obtaining from the above-mentioned specific wave band of above-mentioned interarea distributes.Thus, it is irregular to detect the bigger thickness of mobility scale reliably.

The present invention is also towards checking the irregular method of the thickness of formed film on substrate.

Above-mentioned purpose and other purposes, feature, form and advantage are with reference to accompanying drawing and clear and definite in addition for detailed description of the present invention by what carry out below.

Description of drawings

Fig. 1 is the figure of structure of the irregular testing fixture of expression first embodiment.

Fig. 2 is the figure of expression wavelength band switching mechanism.

Fig. 3 amplifies expression to select near the figure of optical filter.

Fig. 4 is the figure of the relation of the angle of inclination of expression optical filter and the side-play amount that sees through wave band.

Fig. 5 is the figure of the flow process of the irregular inspection of expression thickness.

Fig. 6 is the figure of the flow process of the irregular inspection of expression thickness.

Fig. 7 is the figure of the relation of expression thickness and reflectivity.

Fig. 8 is the figure of relation of the change of expression thickness and reflectivity.

Fig. 9 is the figure that is illustrated in the relation of thickness in the irregular testing fixture of comparative example and reflectivity.

Figure 10 is the figure of structure of the irregular testing fixture of expression second embodiment.

Figure 11 is the figure of structure of the irregular testing fixture of expression the 3rd embodiment.

Figure 12 represents the figure of the relation of thickness and reflectivity.

Figure 13 is the figure of relation of the change of expression thickness and reflectivity.

Figure 14 is the figure of structure of the irregular testing fixture of expression the 4th embodiment.

Figure 15 is the figure of structure of the irregular testing fixture of expression the 5th embodiment.

Figure 16 is the figure of structure of the irregular testing fixture of expression the 6th embodiment.

Figure 17 is the figure of structure of the irregular testing fixture of expression the 7th embodiment.

Figure 18 is the figure of structure of the irregular testing fixture of expression the 8th embodiment.

Figure 19 is the figure of structure of the irregular testing fixture of expression the 9th embodiment.

Figure 20 is the figure of structure of the irregular testing fixture of expression the tenth embodiment.

Embodiment

Fig. 1 is the figure of structure of the irregular testing fixture 1 of expression first embodiment of the invention.Irregular testing fixture 1 is on the glass substrate (following only be called " substrate ") 9 that display device such as liquid crystal indicator are used, and checks the irregular device of thickness of the etchant resist (following only be called " film ") 92 of formed pattern formation usefulness on the interarea 91 of a side.Film 92 on the substrate 9 forms by coating liquid against corrosion on the interarea 91 of substrate 9.

As shown in Figure 1, irregular testing fixture 1 has: objective table 2, and ((+Z) side) among Fig. 1 keeps substrate 9 to its interarea 91 (hereinafter referred to as " upper surface 91 ") that will form film 92 towards upside; Light injection part 3, its upper surface 91 to the substrate 9 that objective table 2 is kept penetrates light; Light accepting part 4, it accepts to penetrate from light injection part 3, and the light that is reflected of the film 92 on the upper surface 91 of substrate 9; Wavelength band switching mechanism 5, it is configured in the wave band of the light that switches light accepting part 4 acceptance between substrate 9 and the light accepting part 4; Travel mechanism 21, it makes objective table 2 relatively move relative to injection part 3, light accepting part 4 and wavelength band switching mechanism 5; Inspection portion 7, it checks that based on the light intensity distribution of accepting at light accepting part 4 (with the regional corresponding distribution of upper surface 91) thickness of film 92 is irregular; And control part 8, it controls these members.In addition, in Fig. 1,, represent the part (too) of wavelength band switching mechanism 5 with section at other embodiments for the ease of diagram.

Objective table 2 (+Z) the black face that frosts is preferably made on the surface of side.Travel mechanism 21 makes ball screw and is connected structure on the motor 211, and by motor 211 rotations, objective table 2 is along guide rail 212, is that the directions X of Fig. 1 moves at the upper surface 91 along substrate 9.

Light injection part 3 has: light source is a Halogen lamp LED 31, and it penetrates white light (light of light of all wave bands that promptly contains the viewing area of the light that has comprised a plurality of wave bands corresponding with the described a plurality of optical filter in back 51); Columned quartz pushrod 32, its Y direction in Fig. 1 vertical with the moving direction of objective table 2 is extended; And the lens pillar 33 that extends in the Y direction.In light injection part 3, Halogen lamp LED 31 is installed in the quartz pushrod 32 (+Y) end of side, the light that incides quartz pushrod 32 from Halogen lamp LED 31 is transformed into the Line of light (promptly becoming beam profile at the light of Y direction than long wire) of extending in the Y direction, and penetrate from the side of quartz pushrod 32, via the upper surface 91 of lens pillar 33 guiding substrates 9.In other words, quartz pushrod 32 and lens pillar 33 become the light from Halogen lamp LED 31 are transformed into along the upper surface 91 of substrate 9 and the Line of light vertical with the moving direction of objective table 2, and the optical system of the upper surface 91 of guiding substrate 9.

In Fig. 1, represent from light injection part 3 to substrate 9 light path (4 light path also is same from substrate 9 to light accepting part) with single-point line.Incident angle (being the formed angle of normal direction of light path and the upper surface 91) θ 1 that incides the relative upper surface 91 of light of substrate 9 from light injection part 3 is 50 °～65 °, is 60 ° in the present embodiment.

The film 92 of a part on the upper surface 91 of substrate 9 of the light that penetrates from light injection part 3 (+Z) face of side (hereinafter referred to as " film upper surface ") is reflected.92 pairs of light from light injection part 3 of film have photopermeability, from the light that is not reflected at the film upper surface in the light of light injection part 3, see through film 92, are reflected at the upper surface 91 (being the lower surface of film 92) of substrate 9.In irregular testing fixture 1, the light that is reflected at the upper surface of the film 92 of substrate 9 and at the interference of light light (following only be called " reflected light ") that the upper surface 91 of substrate 9 is reflected incides light accepting part 4 via wavelength band switching mechanism 5.

Wavelength band switching mechanism 5 has: a plurality of optical filters (for example the half range value is the interference filter of 10nm) 51, and it optionally makes the light of different mutually a plurality of narrow wave bands see through respectively; Discoideus filter wheel 52, it keeps a plurality of optical filters 51; And optical filter rotation motor 53, it is installed in the center of filter wheel 52, rotating filtering sheet rotating disk 52.Filter wheel 52 disposes in the mode of its normal direction with 4 the light path parallel from substrate 9 to light accepting part.

Fig. 2 is the figure of the wavelength band switching mechanism 5 seen from substrate 9 sides along the direction vertical with filter wheel 52.As shown in Figure 2, at filter wheel 52, at the opening 521 of circumferencial direction uniformly-spaced to form 6 circles, 5 openings 521 are equipped with through the mutual 5 kinds of different optical filters 51 of wave band therein.

In wavelength band switching mechanism shown in Figure 15, the driving of the optical filter rotation motor of being controlled by control part 8 53, filter wheel 52 rotations, in 5 optical filters 51 (with reference to Fig. 2), according to thickness that becomes the film 92 of checking object and refractive index etc., select some optical filters 51 (following for 51 differences of other optical filters, be called " selecting optical filter 51a "), be configured in from substrate 9 to light accepting part on 4 the light path.Thus, in from the reflected light of substrate 9 (reflected light that promptly comprise the white light of corresponding with 5 optical filters 51 5 light that see through wave band), have only be configured in light path on the light of the corresponding specific band (hereinafter referred to as " selection wave band ") of selection optical filter 51a, see through and select optical filter 51a, and be directed to light accepting part 4.

And, when driving by optical filter rotation motor 53, during filter wheel 52 rotations, the selection optical filter 51a that is configured in a plurality of optical filters 51 from light injection part 3 to light accepting part on 4 the light path switches to other optical filters 51, the wave band (promptly selecting wave band) of the light that change light accepting part 4 is accepted.Like this, optical filter rotation motor 53 and filter wheel 52 become the optical filter switching mechanism.

As shown in Figure 2, each optical filter 51 is installed in the inboard of circular optical filter frame 54, is that the center is rotatably supported with the optical filter turning axle 55 (representing with the single-point line in Fig. 2) at the center by optical filter frame 54 and optical filter 51.Optical filter turning axle 55 is configured in from substrate 9 to light accepting part at optical filter 51 under the state (being the state of selecting optical filter 51a) on 4 the light path, being that the mode of the Y direction among Fig. 1 is provided with towards the direction of extending (that is, parallel direction) with Line of light from the Line of light of light injection part 3.

Fig. 3 is near the front view of selection optical filter 51a that amplifies expression wavelength band switching mechanism 5, represents its section for the position in the outside of selecting optical filter 51a and optical filter frame 54.As shown in Figure 3, wavelength band switching mechanism 5 also has optical filter leaning device 56, and the optical filter 51a inclination angle of the light path 90 of 4 (with reference to Fig. 1) (representing with the single-point line) from substrate 9 to light accepting part is relatively selected in 56 changes of optical filter leaning device among Fig. 3.In wavelength band switching mechanism 5, by being selected the inclination angle of the relative light path 90 of optical filter 51a by optical filter leaning device 56 change, thereby change sees through wave band (promptly selecting wave band) from the catoptrical selection optical filter 51a of substrate 9 relatively.

Optical filter leaning device 56 has: milscale 561, and its bottom with optical filter frame 54 contacts; Elastic body is a spring 562, and it is installed in the upper end of optical filter frame 54.In wavelength band switching mechanism 5, by release the bottom of optical filter frame 54 by milscale 561, thereby selecting optical filter 51a and optical filter frame 54 is that the clockwise direction rotation among Fig. 3 is pressed at the center with optical filter turning axle 55 together, thus, the inclination angle of the relative light path 90 of optical filter 51a is selected in change.In addition, turn back to original state by milscale 561, utilize the bounce of the spring 562 of contraction state, allow and select optical filter 51a to rotate in the counterclockwise direction, thus, selection optical filter 51a turns back to the state perpendicular to light path 90.

When will select the relative light path 90 of optical filter 51a to tilt by optical filter leaning device 56 time, select optical filter 51a to arrive short wavelength side from the catoptrical center wavelength shift that sees through wave band of substrate 9 relatively.Fig. 4 is that expression is selected the angle of inclination of the relative light path 90 of optical filter 51a and seen through the figure of the centre wavelength of wave band to the relation of the side-play amount of short wavelength side.In addition, select the pitch angle of optical filter 51a, the relative light path 90 vertical states of the selection optical filter 51a among Fig. 3 are made as 0 °.

A plurality of points 301 among Fig. 4 are tilt to select optical filter 51a and the side-play amount of the centre wavelength that sees through wave band of instrumentation, and line 302 is near linears of the instrumentation value of side-play amount.As shown in Figure 4, in wavelength band switching mechanism 5, select optical filter 51a to tilt 1 °, thereby see through wave band only to short wavelength side skew 0.5nm.

In addition, in wavelength band switching mechanism 5, as shown in Figure 2, relative 5 optical filters 51 are respectively arranged with optical filter leaning device 56, thus, the inclination angle of each optical filter 51 relative light path 90 (with reference to Fig. 3) separates separately with other optical filters 51 and changes.

As shown in Figure 1, light accepting part 4 has: with a plurality of photo detectors is CCD (Charge CoupledDevice: charge-coupled image sensor) arrange the linear sensor 41 that forms on Y direction linearity ground, and be configured in from substrate 9 to linear sensor on 41 the light path, promptly be configured in the collector lens 42 between the selection optical filter 51a of linear sensor 41 and wavelength band switching mechanism 5.Penetrating from light injection part 3, and on the upper surface 91 of substrate 9, in the Line of light (i.e. Line of light after upper surface 91 reflections at substrate 9) after the film 92 of the irradiation area (hereinafter referred to as " wire irradiation area ") of the linearity that the Y direction is extended is reflected, collector lens 42 will see through the light of the selection wave band of selecting optical filter 51a and assemble to linear sensor 41.Linear sensor 41 is accepted the light by the selection wave band of collector lens 42 optically focused and imaging, obtains the light intensity of being accepted and distributes (promptly from the distribution in the Y direction of the output valve of each CCD), and output to inspection portion 7.In irregular testing fixture 1, in the moving of substrate 9 and objective table 2, obtain the catoptrical intensity distributions of the film 92 that forms on the upper surface 91 of comfortable substrate 9 repeatedly by linear sensor 41.

Inspection portion 7 has: image production part 71, and it accepts the output from linear sensor 41, generates the two dimensional image of the upper surface 91 of substrate 9; And irregular test section 72, the thickness that its pixel value from each pixel of the two dimensional image that generated by image production part 71 detects membrane 92 is irregular.

Then, the flow process at the irregular inspection of thickness of irregular testing fixture 1 describes.Fig. 5 and Fig. 6 are the figure of flow process of the inspection of the irregular testing fixture 1 of expression.When the thickness of the film 92 on the upper surface 91 of checking substrate 9 by irregular testing fixture 1 shown in Figure 1 is irregular, at first, will be with respect to characteristic as the material of the film 92 of checking object and thickness etc., having the suitable selection optical filter 51a that sees through wave band is configured under the state on the light path, as required, the operator tilts to select optical filter 51a by the optical filter leaning device 56 of selecting optical filter 51a, and optical filter 51a from substrate 9 to linear sensor the inclination angle of 41 light path (perhaps changing the inclination angle in advance) is relatively selected in change.Thus, the center wavelength shift that sees through wave band of selecting optical filter 51a selects wave band to be adjusted to the thickness irregular (step S11) of the range detection film 92 that is more suitable for to short wavelength side.

Then, keep substrate 9 on the objective table 2 of the inspection starting position of in being located at Fig. 1, representing with solid line after, substrate 9 and objective table 2 beginnings to (+X) direction moves (step S12).Then, penetrate Line of light irradiation the wire irradiation area (step S13) on the upper surface 91 of substrate 9 of the upper surface 91 of also relative substrate 9 with 60 ° of incidents of incident angle from light injection part 3, the wire irradiation area relatively moves relative to substrate 9.

Light from light injection part 3 is reflected at the upper surface 91 of substrate 9, by seeing through the selection optical filter 51a of wavelength band switching mechanism 5, have only after the light of specific band (for example centre wavelength is that 550nm, half range value are 10nm) is removed, be directed to light accepting part 4.In light accepting part 4, the light of the selection wave band after the reflection of the upper surface 91 of substrate 9 is accepted (step S14) via collector lens 42 by linear sensor 41, obtains in the intensity distributions (step S15) from the catoptrical selection wave band of the wire irradiation area on the substrate 9.Output valve from each CCD of linear sensor 41 is sent to inspection portion 7 image production parts 71.

In irregular testing fixture 1, by control part 8, in the moving of substrate 9, confirm repeatedly whether substrate 9 and objective table 2 have moved to the inspection end position of representing with double dot dash line (step S16) in Fig. 1, when not moving to the inspection end position, then turn back to step S14, carry out obtain (step S14, the S15) that the light intensity of the selection wave band of the acceptance of light of the selection wave band in the reflected light and wire irradiation area distributes repeatedly.In irregular testing fixture 1, objective table 2 (+during X) direction moves, by the action of step S14～S16 repeatedly, obtain catoptrical intensity distributions repeatedly, thereby obtain in intensity distributions from the catoptrical selection wave band of the upper surface 91 of whole base plate 9 from the wire irradiation area on the substrate 9.

And when substrate 9 and objective table 2 move to (step S16) when checking end position, the substrate 9 and the mobile of objective table 2 that are undertaken by travel mechanism 21 are stopped, and the irradiation of illumination light also is stopped (step S17).In the image production part 71 of inspection portion 7, for the intensity distributions that obtains by light accepting part 4 from the catoptrical selection wave band of upper surface 91, emphasize to result from the thickness change brightness value difference Flame Image Process (for example, two dimensional image (hereinafter referred to as " original image ") to the intensity distributions on the expression upper surface 91, carrying out smoothing by medial filter handles, ask for the smoothing image, with the value of each pixel of original image divided by smoothing image corresponding pixel value, thereby remove processing such as change than the brightness value of the also big and whole wide region that causes by thickness change), will be changed the two dimensional image (hereinafter referred to as " emphasizing image ") (step S21) of the upper surface 91 that the change as pixel value shows by emphatic thickness thereby generate.

The image of emphasizing that generates is displayed on the display device such as display as required, and then, by the irregular test section 72 of inspection portion 7 based on emphasizing that image carries out the irregular detection of thickness (step S22).

Fig. 7 is the figure that is illustrated in the relation of the thickness of the film 92 that forms on the upper surface 91 of substrate 9 and reflectivity.Line 101 among Fig. 7 is illustrated in the reflectivity (promptly being 60 ° reflection of light rate to incident angle) of the condition identical with the irregular testing fixture 1 of present embodiment, and line 102 expressions are reflectivity 30 °, under the condition identical with the testing fixture of described the 5th embodiment in back from the light of injection part to the incident angle of substrate.Line 101,102 expressions are the reflection of light rate of 550nm to wavelength, and when the change wavelength, the relation of thickness and reflectivity also changes.

As shown in Figure 7, the reflectivity of film 92 is also different simultaneously owing to the thickness when film 92, so the catoptrical intensity of accepting at light accepting part 4 is also different.Therefore, exist when irregular in the film thickness distribution of film 92, the two dimensional image of the upper surface 91 of the substrate 9 that generates at image production part 71 (original image and emphasize image) by inspection portion 7, also pixel value produce irregular.In irregular testing fixture 1, check the extent of deviation of pixel value of each pixel of emphasizing image of upper surfaces 91 by the irregular test section 72 of inspection portion 7, when having extent of deviation than also big regional of predefined irregular threshold value, the zone of the correspondence on the upper surface 91 is as existing the irregular zone of thickness that surpasses allowed band to be detected.

But, as shown in Figure 7, the reflectivity of film 92 with respect to the change of thickness with cyclical movement.Fig. 8 is the figure of change of the reflectivity of thickness when only changing 1nm of expression film 92.As Fig. 7 and shown in Figure 8, near the maximal point of reflectivity and near the minimal point, the change of the reflectivity relative with the change of thickness becomes very little.Therefore, when thickness change was very little, in the two dimensional image that is generated by image production part 71 (original image and emphasize image), pixel value changed hardly, the precise decreasing of the detection of irregular (being the change of thickness) of being undertaken by irregular test section 72.Below, the thickness zone that the ratio of the change of reflectivity that will be relative with the change of thickness is very little is called " low sensitivity region ".

Suppose that when the low sensitivity region change of the line 101 of thickness in Fig. 7 of the film on the substrate 9 92, it is irregular to be difficult to only to go out this thickness based on line 101 high Precision Detection.Therefore, in irregular testing fixture 1, as mentioned above, with 1 optical filter 51 as selecting optical filter 51a, carry out the irregular detection back of the thickness first time (step S23), by the optical filter rotation motor 53 of control part 8 driving wavelength band switching mechanism 5, filter wheel 52 rotations, other optical filters 51 are configured in from substrate 9 to light accepting part on 4 the light path, the selection wave band (step S231) of change wavelength band switching mechanism 5.Select wave band by change, the low sensitivity region of thickness also moves.

Then, if desired, perhaps change to the inclination angle of new relatively selection optical filter 51a light path in advance by optical filter leaning device 56, adjust and select wave band, by travel mechanism 21, objective table 2 turns back to checks the starting position, begins move (step S11, the S12) of substrate 9 and objective table 2 once more.In irregular testing fixture 1, till objective table 2 arrives the inspection end position, from the light of light injection part 3 in the reflected light of substrate 9, the light of different selection wave bands when accepting with for the first time irregular the detection by light accepting part 4, obtain catoptrical intensity distributions repeatedly from the wire irradiation area on the substrate 9, and deliver to after the image production part 71 of inspection portion 7, substrate 9 and the mobile of objective table 2 are stopped, and the irradiation of illumination light also is stopped (step S13～S17).

And, by the image production part 71 of inspection portion 7, generate substrate 9 upper surface 91 emphasize image (step S21), by irregular test section 72, detect the thickness irregular (step S22) of the film 92 on the upper surface 91.When the irregular detection of the thickness second time finishes (step S23), based on the first time and secondary testing result, the thickness that finally detects formed film 92 on the upper surface 91 of substrate 9 is irregular, thus the irregular detection of thickness that end is undertaken by irregular testing fixture 1.

In irregular testing fixture 1, switch between different mutually a plurality of wave bands by a plurality of optical filters 51 of wavelength band switching mechanism 5 and to select wave band, thereby in irregular detection for the first time and the irregular detection second time, make the low sensitivity region of thickness different.Thus, even during the low sensitivity region when the part (perhaps whole) of the amplitude of variation of the thickness of film 92 is included in for example for the first time irregular the detection, because low sensitivity region difference when irregular detections for the second time, change so also can the precision higher detection go out thickness to the part that is included in low sensitivity region when for the first time irregular the detection.

But, in irregular testing fixture 1, be set as 60 ° to the incident angle θ 1 of the light of substrate 9 incidents from light injection part 3, with incident angle is that the irregular testing fixture of 30 ° second embodiment is compared, and incident angle is big, so, as shown in Figure 7, the variable cycle of the reflectivity relative with thickness becomes big.Consequently, the zone that can carry out the irregular detection of high precision, the bigger zone, inclination angle of the line 101 between the adjacent low sensitivity region becomes big.Like this, in irregular testing fixture 1, light from light injection part 3 is big to incident angle θ 1 change of substrate 9, especially in this irregular testing fixture, also bigger than the incident angle that is set as 45 ° usually, be set as 50 ° or more than it specifically, thereby can make the scope of the thickness that can carry out the irregular detection of high precision become big.

The figure of the thickness of the film 92 of Fig. 9 when to be expression from the incident angle of the light of light injection part be 70 ° and the relation of reflectivity.As shown in Figure 9, when incident angle was 70 °, near the maximal point of reflectivity, the width of low sensitivity region broadened significantly.In irregular testing fixture 1, be made as 65 ° or below it by incident angle θ 1, thereby can prevent that near the maximal point of reflectivity, the width of low sensitivity region broadens the relative substrate 9 of light.

Like this, in irregular testing fixture 1, by will be from the light of light injection part 3 the incident angle θ 1 of relative substrate 9 be set as 50 °～60 °, thereby the scope that can make the thickness that can carry out the irregular detection of high precision becomes big, simultaneously can prevent that near the maximal point of reflectivity, the width of low sensitivity region broadens.Consequently, prevent that the change of thickness is comprised in the low sensitivity region, thus can precision to detect small thickness than the highland irregular.In irregular testing fixture 1, because be fixed at incident angle θ 1 under 60 ° the state from the relative substrate 9 of light of light injection part 3, can realize high-precision irregular detection, so there is no need to be provided with the mechanism of the incident angle that changes the relative substrate 9 of light, can simplify the structure of irregular testing fixture 1.

In addition, film 92 most cases on the upper surface 91 of substrate 9 easily form by coating liquid coating, to detect small thickness than the highland irregular because irregular testing fixture 1 can precision, so be particularly suitable for the detection of the thickness irregular (promptly applying irregular) of the film 92 that forms by this coating liquid coating.

In irregular testing fixture 1, rotating filtering sheet rotating disk 52, will be from substrate 9 to light accepting part selection optical filter 51a on 4 the light path switch to other optical filter 51, thereby can easily change the catoptrical wave band of accepting at light accepting part 4 from substrate 9 (promptly selecting wave band), select appropriate wave band.In addition, penetrate Line of light from light injection part 3, with moving synchronously of substrate 9, accept the reflected light that moves in vertical direction relative to Line of light repeatedly by linear sensor 41, thereby the incident angle θ 1 of the light of relative substrate 9 can be made as constant in entire upper surface 91 from substrate 9.Thus, because in the irregular detection of thickness, do not need to consider the influence that causes by incident angle, handle so can simplify the irregular detection of being undertaken by irregular test section 72 of thickness to reflectivity.

But, in irregular testing fixture 1, select the optical filter 51a inclination angle of 41 light path from substrate 9 to linear sensor relatively by optical filter leaning device 56 change, thereby can precision see through wave band (promptly selecting wave band) from the catoptrical selection optical filter 51a of substrate 9 relatively than the highland adjustment.Consequently, adjust corresponding to the characteristic of the material of film 92 and thickness etc. by selecting wave band, thereby can improve the irregular accuracy of detection of thickness.In addition, in many irregular testing fixtures, even when selecting the seeing through wave band foozle (for example in centre wavelength error about 3nm being arranged) is arranged of optical filter, the shortest selection optical filter of wave band and centre wavelength that sees through of the selection optical filter by making other devices adapts, thereby can precision than the highland make select optical filter see through the wave band unanimity, remove the individual difference between many table apparatus, can realize stable inspection.

In wavelength band switching mechanism 5, a plurality of relatively optical filters 51 are respectively arranged with optical filter leaning device 56, so can change the inclination angle of each optical filter 51 relative light path separately, thereby the wave band that sees through of each optical filter 51 can be adjusted separately corresponding to the characteristic of film 92.In irregular testing fixture 1, usually check that continuously the thickness of many congener substrates 9 is irregular, but since two optical filters 51 can adjusting inspection separately and utilized see through wave band, so the change at the inclination angle of optical filter 51 only gets final product when the inspection of first substrate 9, after this, do not need to carry out the change at inclination angle.Like this, in irregular testing fixture 1, when the thickness of checking many substrates 9 continuously is irregular, can simplify the adjustment operation that sees through wave band of optical filter 51.

In wavelength band switching mechanism 5, select optical filter 51a being that the optical filter turning axle 55 of Y direction be that the center rotates towards the direction of extending from the Line of light of light injection part 3, thereby on the whole length that incides the Line of light of selecting optical filter 51a, it is constant that Line of light is selected the incident angle of optical filter 51a relatively.Thus in the central portion and both ends of Line of light, prevent the small skew that sees through wave band that the small difference by the incident angle of relative selection optical filter 51a causes, can prevent the decline of the accuracy of detection that thickness is irregular.

In irregular testing fixture 1, even to detect thickness irregular owing to accept reflected light from substrate 9 by linear sensor 41, so when substrate 9 does not have photopermeability, can check suitably that also thickness is irregular.And then, by making light oblique illumination from light injection part 3 to substrate 9, thereby can avoid overlapping near the light path of the light incident side that causes and reflection side, prevent that the structure of light injection part 3 and light accepting part 4 and configuration from becoming complicated by light injection part 3 and light accepting part 4.

Then, the testing fixture 1a at second embodiment of the present invention describes.Figure 10 is the figure of the structure of the irregular testing fixture 1a of expression.In irregular testing fixture 1a, replace the optical filter leaning device 56 of irregular testing fixture 1 shown in Figure 3, as shown in figure 10, being provided with filter wheel 52 is the optical filter leaning device 56a of center rotation with optical filter turning axle 55a.Other structures are identical with Fig. 1, indicate identical Reference numeral in the following description.

As shown in figure 10, in the wavelength band switching mechanism 5 of irregular testing fixture 1a, optical filter leaning device 56a is installed in filter wheel 52 opposition sides with optical filter rotation motor 53, optical filter leaning device 56a is the center with the optical filter turning axle 55a towards the Y direction, press the clockwise direction rotation of Figure 10, thus the also rotation in the direction of the clock of optical filter rotation motor 53 and filter wheel 52.Thus, select optical filter 51a and other optical filters 51 to tilt (promptly together, 5 optical filter 51 integral inclinations), the optical filter 51a angle of inclination of 41 light path from substrate 9 to linear sensor is relatively selected in change, selects wave band (promptly relatively from the wave band that sees through of the catoptrical selection optical filter 51a of substrate 9) also to change.

The inspection flow process and first embodiment that the thickness of the irregular testing fixture 1a of second embodiment is irregular are roughly the same, describe below with reference to Fig. 5 and Fig. 6.When the irregular inspection of the thickness that carries out film 92 by irregular testing fixture 1a, at first, automatically change the inclination angle of selecting optical filter 51a by optical filter leaning device 56a, select the adjustment (step S11) of wave band.Then, substrate 9 and objective table 2 begin to move, and the white light of wire penetrates from light injection part 3a, and are irradiated onto the wire irradiation area (step S12, S13) on the substrate 9.

Light from light injection part 3a is reflected at the upper surface 91 of substrate 9, by seeing through the selection optical filter 51a of wavelength band switching mechanism 5, has only and selects the light of wave band to be removed, and be directed to light accepting part 4.In light accepting part 4, light from the selection wave band of wavelength band switching mechanism 5 is accepted by linear sensor 41, reflected light from the wire irradiation area on the substrate 9 is obtained in the intensity distributions of selecting wave band, and is sent to the image production part 71 (step S14, S15) of inspection portion 7.

In irregular testing fixture 1a, till objective table 2 arrives inspection end position (step S16), obtain catoptrical intensity distributions repeatedly, thereby obtain from the reflected light of upper surface 91 at the intensity distributions of selecting wave band (step S14～S16) from the wire irradiation area on the substrate 9.Then, the irradiation mobile and illumination light of substrate 9 and objective table 2 is stopped (step S17), when emphasizing image, by the thickness that irregular test section 72 detects formed film 92 on upper surface 91 irregular (step S21, S22) by image production part 71 generations.

When the irregular detection of the thickness first time finishes, select optical filter 51a to change selection wave band (step S23, S231) by switching in wavelength band switching mechanism 5, turn back to step S11, change is automatically selected after the inclination angle of optical filter 51a as required, carries out the irregular detection of thickness for the second time (step S11～S17, S21～S23).And based on the first time and secondary testing result, the thickness that finally detects formed film 92 on the upper surface 91 of substrate 9 is irregular, finishes the irregular detection of being undertaken by irregular testing fixture 1a of thickness.

As described above, in irregular testing fixture 1a also with first embodiment in the same manner, select wave band to carry out twice irregular detection of thickness by change, thus can precision to detect thickness than the highland irregular.In addition, be made as 50 °～65 ° by incident angle θ 1, thereby the amplitude of variation that can prevent thickness is comprised in the low sensitivity region from the light of injection part 3 with relative substrate 9, can precision to detect small thickness than the highland irregular.

In irregular testing fixture 1a, utilize optical filter leaning device 56a, the inclination angle of the relative light path of optical filter 51a is selected in change, thereby with first embodiment in the same manner, can precision select optical filter 51a relatively from the catoptrical wave band (promptly selecting wave band) that sees through of substrate 9 than the highland adjustment.Consequently, allow and select wave band to adjust, thereby can improve the irregular accuracy of detection of thickness corresponding to the characteristic of film 92, and then, can in many irregular testing fixtures, precision make selection wave band unanimity than the highland.Irregular testing fixture 1a also is particularly suitable for the detection of the thickness irregular (promptly applying irregular) of the film 92 that forms by the coating of coating liquid.

In the wavelength band switching mechanism 5 of irregular testing fixture 1a, special owing to utilizing 1 optical filter leaning device 56a integrally to change the inclination angle of a plurality of optical filter 51 relative light paths, so can simplify the mechanism that a plurality of optical filters 51 is seen through the adjustment of wave band.In addition, with first embodiment in the same manner, select optical filter 51a being that the optical filter turning axle 55a of Y direction is the center rotation towards the direction of extending from the Line of light of light injection part 3, Line of light selects the incident angle of optical filter 51a to be set as constant relatively on a wire polishing length thus, can prevent the decline of the accuracy of detection that thickness is irregular.

In irregular testing fixture 1a, with first embodiment in the same manner even to detect thickness irregular owing to accept reflected light from substrate 9, so when substrate 9 does not have photopermeability, can check rightly that also thickness is irregular.In addition, by making light oblique illumination from light injection part 3 on substrate 9, can prevent that the structure of light injection part 3 and light accepting part 4 and configuration from becoming complicated.

Then, the irregular testing fixture 1b at third embodiment of the invention describes.Figure 11 is the figure of the structure of the irregular testing fixture 1b of expression.As shown in figure 11, irregular testing fixture 1b except that each structure with irregular testing fixture 1 shown in Figure 1, also has polariscope 6, it is configured in from substrate 9 to wavelength band switching mechanism on 5 the light path, and optionally makes from S polarized light in the reflected light of film 92 and see through.

The flow process of the inspection that the thickness that is undertaken by irregular testing fixture 1b is irregular, roughly the same with first embodiment, describe below with reference to Fig. 5 and Fig. 6.When the irregular inspection of the thickness that carries out film 92 by irregular testing fixture 1b, at first, change the inclination angle of selecting optical filter 51a as required by optical filter leaning device 56 (with reference to Fig. 3), select the adjustment (step S11) of wave band.Then, substrate 9 and objective table 2 begin to move, and the white light of wire penetrates and is irradiated onto on the wire irradiation area on the substrate 9 (step S12, S13) from light injection part 3.

Light from light injection part 3 is reflected at the upper surface 91 of substrate 9, has only the S polarized light to be removed by seeing through polariscope 6.And, by seeing through the selection optical filter 51a of wavelength band switching mechanism 5, have only the light of selecting wave band by after the S polarized light takes out, select the light of wave band to be directed to light accepting part 4.In light accepting part 4, S polarized light from the selection wave band of wavelength band switching mechanism 5 is accepted by linear sensor 41, in reflected light from the wire irradiation area on the substrate 9, the S polarized light is obtained in the intensity distributions of selecting wave band, and is sent to the image production part 71 (step S14, S15) of inspection portion 7.

In irregular testing fixture 1b, till objective table 2 arrives the inspection end position (step S16), obtain catoptrical intensity distributions repeatedly from the wire irradiation area on the substrate 9, thereby in the reflected light from upper surface 91, obtain intensity distributions (the step S14～S16) of the selection wave band of S polarized light.Then, the irradiation mobile and illumination light of substrate 9 and objective table 2 is stopped (step S17), when emphasizing image, by the thickness that irregular test section 72 detects formed film 92 on upper surface 91 irregular (step S21, S22) by image production part 71 generations.

When the irregular detection of the thickness first time finishes, select optical filter 51a to change selection wave band (step S23, S231) by switching at wave band switching construction 5, return step S11, change as required after the inclination angle of selecting optical filter 51a, carry out the irregular detection of thickness for the second time (step S11～S17, S21～S23).And based on the first time and secondary testing result, the thickness that finally detects formed film 92 on the upper surface 91 of substrate 9 is irregular, finishes the irregular detection of thickness of irregular testing fixture 1b and handles.

Figure 12 is the figure of the relation of the thickness of formed film 92 and reflectivity on the upper surface 91 of expression substrate 9.Line 121 among Figure 12 is illustrated in reflectivity under irregular testing fixture 1b the same terms with the present embodiment reflectivity of S polarized light (promptly to).In addition, line 122 is illustrated in and has omitted reflectivity under device (i.e. the irregular testing fixture 1 of first embodiment) the same terms of polariscope 6 reflectivity of the light (hereinafter referred to as " nonpolarized light ") of not being partial to (promptly to) from irregular testing fixture 1b, line 123 is illustrated in the polariscope 6 that replaces irregular testing fixture 1b, and is provided with reflectivity under the identical condition of other polariscopic devices that the P polarized light the is seen through reflectivity of P polarized light (promptly to).Line 121～123 expressions are the reflection of light rate of 550nm to wavelength.

Figure 13 is the figure of the change of the thickness that is illustrated in film 92 reflectivity when only changing 1nm.Line 201～203 among Figure 13 corresponding to the line among Figure 12 121～123, is represented the change to the reflectivity of S polarized light, nonpolarized light and P polarized light respectively.

As shown in figure 13, since to the change of the reflectivity of S polarized light greater than change to the reflectivity of nonpolarized light and P polarized light, so in irregular testing fixture 1b, the light that to be accepted at light accepting part 4 by polariscope 6 is as the S polarized light, check that based on the intensity distributions of S polarized light thickness is irregular, thereby can obtain in high sensitivity with the change of thickness as change at the pixel value of emphasizing image.Like this, in irregular testing fixture 1b, the irregular sensitivity of thickness is improved, thereby it is irregular to detect thickness more accurately by making.

In irregular testing fixture 1b, because polariscope 6 is configured in (being on the light path of sensitive side) between substrate 9 and the linear sensor 41, so can prevent from the influence of the heat of injection part 3 to polariscope 6.In addition,, improved the degree of freedom of the configuration of polariscope 6, therefore the structure complicated that can prevent locking apparatus by polariscope 6 is configured between substrate 9 and the wavelength band switching mechanism 5.

Then, the irregular testing fixture 1c at four embodiment of the invention describes.Figure 14 is the figure of the structure of the irregular testing fixture 1c of expression.As shown in figure 14, in irregular testing fixture 1c, the polariscope 6 that the S polarized light is seen through is configured on the collector lens 42 and the light path between the linear sensor 41 of light accepting part 4.Other structures are identical with Figure 11, indicate identical Reference numeral in the following description.In addition, the irregular inspection flow process and the 3rd of thickness of being undertaken by irregular testing fixture 1c

Embodiment is identical.

In irregular testing fixture 1c, be reflected at the upper surface 91 of substrate 9 from the light of light injection part 3, by seeing through the selection optical filter 51a of wavelength band switching mechanism 5, have only and select the light of wave band to be removed, and be directed to light accepting part 4.In light accepting part 4, assemble by collector lens 42 from the light of the selection wave band of wavelength band switching mechanism 5, and be directed to polariscope 6, only take out the S polarized light by seeing through polariscope 6, in linear sensor 41 imagings and be accepted.

In irregular testing fixture 1c, with the 3rd embodiment in the same manner, check that based on the intensity distributions of S polarized light thickness is irregular, the thickness that can detect membrane 92 more accurately is irregular.In addition, because polariscope 6 is configured in (being on the light path of sensitive side) between substrate 9 and the linear sensor 41, so can prevent from the influence of the heat of light injection part 3 to polariscope 6.In irregular testing fixture 1c, especially, because polariscope 6 is configured between collector lens 42 and the linear sensor 41, so polariscope 6 can be made and the corresponding size of Line of light by collector lens 42 convergences.Therefore, the situation of (for example from light injection part 3 to collector lens on 42 the light path) of comparing with the front that polariscope 6 is configured in collector lens 42 is compared, and can make polariscope 6 miniaturizations.

Then, the irregular testing fixture 1d at fifth embodiment of the invention describes.Figure 15 is the figure of the structure of the irregular testing fixture 1d of expression.As shown in figure 15, in irregular testing fixture 1d, the polariscope 6 that the S polarized light is seen through is configured on the lens pillar 33 and the light path between the substrate 9 of light injection part 3.Other structures are identical with Figure 11, indicate identical Reference numeral in the following description.In addition, the irregular inspection flow process of the thickness that is undertaken by irregular testing fixture 1d is identical with the 3rd embodiment.

In irregular testing fixture 1d, by the light transmission polariscope 6 that allows from light injection part 3, have only the S polarized light to be removed, and be directed to substrate 9, the S polarized light that is reflected at the upper surface 91 of substrate 9 is by seeing through the selection optical filter 51a of wavelength band switching mechanism 5, have only and select the light of wave band to be removed, and be directed to light accepting part 4.In light accepting part 4, assembled by collector lens 42 from the light of the selection wave band of wavelength band switching mechanism 5, in linear sensor 41 imagings and be accepted.

In irregular testing fixture 1d, with the 3rd embodiment in the same manner, by checking that based on the intensity distributions of S polarized light thickness is irregular, thereby the thickness that can detect membrane 92 more accurately is irregular.Particularly to (for example having formed the more coarse film 92 of surface ratio, the scattered light that light comprised of substrate 9 reflection align catoptrical ratio be 1% or film 92 more than it) substrate 9 when carrying out the irregular inspection of thickness, by polariscope 6 being configured in (being on the light path of emitting side) between light injection part 3 and the substrate 9, thereby compare with the situation that polariscope 6 is configured in (being on the light path of sensitive side) between substrate 9 and the linear sensor 41, it is irregular to detect thickness more accurately.

Then, the irregular testing fixture 1e at sixth embodiment of the invention describes.Figure 16 is the figure of the structure of the irregular testing fixture 1e of expression.In irregular testing fixture 1e, different from the light of light injection part 3 incident angle θ 2 with the incident angle θ 1 of irregular testing fixture 1 shown in Figure 1 to substrate 9, be set as 10 °～40 ° (being 30 ° in the present embodiment).Other structures are identical with Fig. 1, indicate identical Reference numeral in the following description.

As shown in figure 16, irregular testing fixture 1e, with first embodiment in the same manner, have: objective table 2, it keeps substrate 9; Light injection part 3, its upper surface 91 to the film that is formed with photopermeability 92 that is maintained at the substrate 9 on the objective table 2 penetrates light; Wavelength band switching mechanism 5, it makes the light transmission from the selection wave band in the reflected light of substrate 9, switches between different mutually a plurality of wave bands simultaneously and selects wave band; Light accepting part 4, it accepts to see through the light of wavelength band switching mechanism 5, obtains the distribution of light intensity on upper surface of selecting wave band; Travel mechanism 21, it moves objective table 2; Inspection portion 7, it is irregular based on the distribute thickness of checking film 92 of the light intensity of obtaining at light accepting part 4; And control part 8, it controls these structures.

Wavelength band switching mechanism 5, with first embodiment in the same manner, have: a plurality ofly (also be 5 in the present embodiment.With reference to Fig. 2) optical filter 51, it optionally makes the light of different mutually a plurality of narrow wave bands see through respectively; Discoideus filter wheel 52, it keeps 5 optical filters 51; And optical filter rotation motor 53, its rotating filtering sheet rotating disk 52.In wavelength band switching mechanism 5,, thereby the selection optical filter 51a that is configured in a plurality of optical filters 51 from light injection part 3 to light accepting part on 4 the light path can be switched to other optical filters 51 by optical filter rotation motor 53 rotating filtering sheet rotating disks 52.

Wavelength band switching mechanism 5 also has optical filter leaning device 56 (with reference to Fig. 3), and the optical filter 51a inclination angle of 4 light path from substrate 9 to light accepting part is relatively selected in its change.In wavelength band switching mechanism 5, as shown in Figure 2, be respectively arranged with optical filter leaning device 56 with respect to 5 optical filters 51, thus, the inclination angle of the relative light path of each optical filter 51 can separate change separately with other optical filters 51.

Light injection part 3 is also identical with first embodiment, has: light source is a Halogen lamp LED 31, and it penetrates white light, and this white light contains the light that comprises a plurality of wave bands corresponding with a plurality of optical filter 51; Quartz pushrod 32, it will be transformed to Line of light from the light of Halogen lamp LED 31; And lens pillar 33, it will be from the Line of light guiding substrate 9 of quartz pushrod 32.Light accepting part 4 also has: linear sensor 41, and it is arranged by a plurality of CCD linearities ground and forms; And collector lens 42, it is arranged between the selection optical filter 51a of linear sensor 41 and wavelength band switching mechanism 5.

Then, the flow process at the irregular inspection of the thickness that is undertaken by irregular testing fixture 1e describes.The flow process of the inspection of being undertaken by irregular testing fixture 1e is identical with first embodiment, describes below with reference to Fig. 5 and Fig. 6.When the thickness of the film 92 on the upper surface 91 of being checked substrate 9 by irregular testing fixture 1e is irregular, at first, change the inclination angle of selecting optical filter 51a as required by optical filter leaning device 56, select the adjustment (step S11) of wave band, the inspection starting position of representing with solid line from Figure 16 begins move (the step S12) of objective table 2.

Then, relatively the upper surface 91 of substrate 9 is irradiated onto irradiation area on the upper surface 91 with the Line of light of 30 ° of incidents of incident angle, reflected light from substrate 9 only becomes the light of selecting wave band by selecting optical filter 51a, and accept by linear sensor 41, obtain from the reflected light of the irradiation area on the substrate 9 at the intensity distributions of selecting wave band (step S13～S15).

In irregular testing fixture 1e, with moving synchronously of objective table 2, obtain catoptrical intensity distributions repeatedly from the irradiation area on the substrate 9, when objective table 2 arrived the inspection end position of representing with double dot dash line among Figure 16, the irradiation mobile and illumination light of objective table 2 was stopped (step S16, S17).And, generate upper surface 91 emphasize image in, detect the thickness irregular (step S21, S22) on the upper surface 91.

When the irregular detection of the thickness first time finishes, select optical filter 51a to change selection wave band (step S23, S231) in wavelength band switching mechanism 5 by switching, turn back to step S11, change is selected after the inclination angle of optical filter 51a as required, carries out the irregular detection of thickness for the second time (step S11～S17, S21～S23).And based on the first time and secondary testing result, the thickness that finally detects formed film 92 on the interarea upper surface 91 of substrate 9 is irregular, finishes the irregular detection of being undertaken by irregular testing fixture 1a of thickness.

As described above, in irregular testing fixture 1e, be set as 30 ° from light injection part 3 to the incident angle θ 2 of the light of substrate 9 incidents, as shown in Figure 7, with incident angle θ 1 is that the testing fixture 1 of 60 ° first embodiment is compared, because near the width the maximal point of the relative reflectivity of thickness less (difference that promptly begins to become to the inclination angle of line 102 thickness till big from maximal point is less), so near the width of the low sensitivity region maximal point diminishes.Thus, when the bigger thickness of the mobility scale that detects thickness is irregular, can prevent that whole thickness mobility scale is comprised in the low sensitivity region.In other words, at least a portion of the mobility scale of thickness is comprised between the low sensitivity region that adjoins each other and may carries out in the zone of irregular detection with high sensitivity.Like this, in irregular testing fixture 1e, the incident angle θ 2 from the light of light injection part 3 by relative substrate 9 diminishes, thereby it is special also littler than the incident angle that is set as 45 ° usually in this irregular testing fixture, be set as 40 ° or below it specifically, in the irregular detection of the bigger thickness of thickness change, can prevent that the mobility scale of whole thickness is included in the low sensitivity region thus.

In addition, in irregular testing fixture 1e, be set as 10 ° or more than it by incident angle θ 2 with the light of the relative substrate 9 of light, thereby avoid overlapping near the light path of the light incident side that brings and reflection side, can prevent that the structure of light injection part 3 and light accepting part 4, wavelength band switching mechanism 5 and configuration from becoming complicated by light injection part 3 and light accepting part 4.

Like this, in irregular testing fixture 1e, by will be from the light of injection part 3 the incident angle θ 2 of relative substrate 9 be made as 10 °～40 °, thereby can prevent that apparatus structure is complicated, simultaneously when the bigger thickness of detection thickness change is irregular, the mobility scale that prevents whole thickness is included in the low sensitivity region, and it is irregular to detect thickness reliably.

In addition, in irregular testing fixture 1e, a plurality of optical filters 51 by wavelength band switching mechanism 5 switch wave band between different mutually a plurality of wave bands, the low sensitivity region of the thickness in the time of can changing irregular detect thus rightly, and it is irregular to detect the bigger thickness of thickness change more reliably.Irregular testing fixture 1e, also with first embodiment in the same manner, be particularly suitable for the detection of the thickness irregular (promptly applying irregular) of the film 92 that forms by the coating of coating liquid.

In irregular testing fixture 1e, with first embodiment in the same manner, to select optical filter 51a to switch to other optical filter 51 by rotating filtering sheet rotating disk 52, and can easily change the catoptrical wave band of accepting at light accepting part 4 from substrate 9 (promptly selecting wave band) thus.In addition, by by linear sensor 41, with the Line of light of accepting synchronously from light injection part 3 that moves of substrate 9, thereby, handle so can simplify the irregular detection of being undertaken by irregular test section 72 of thickness owing to the incident angle θ 2 with the relative substrate 9 of light is set as constant in entire upper surface 91.

In wavelength band switching mechanism 5, with first embodiment in the same manner, by selecting the inclination angle of the relative light path of optical filter 51a by optical filter leaning device 56 change, thereby can precision select optical filter 51a relatively from the catoptrical wave band (promptly selecting wave band) that sees through of substrate 9 than the highland adjustment.Consequently, select wave band to adjust by allowing, thereby can improve the irregular accuracy of detection of thickness corresponding to the characteristic of film 92, and then, can be in many irregular pick-up units, precision makes than the highland and selects the wave band unanimity.

In addition, in wavelength band switching mechanism 5, select optical filter 51a being that the optical filter turning axle 55 of Y direction be that the center rotates towards the direction of extending from the Line of light of light injection part 3, on the whole length that incides the Line of light of selecting optical filter 51a, Line of light selects the incident angle of optical filter 51a to be set as constant relatively thus.Thus,, prevent the small skew that sees through wave band that the small difference by the incident angle of relative selection optical filter 51a causes, can prevent the decline of the accuracy of detection that thickness is irregular at the central portion and the both ends of Line of light.

In addition, irregular testing fixture 1e in most of the cases because only precision is higher carries out irregular detection with regard to energy with 1 optical filter, so wavelength band switching mechanism 5 can be replaced as 1 fixedly optical filter, can omit step S23, the S231 of Fig. 6.

Then, the irregular testing fixture 1f at the 7th embodiment describes.Figure 17 is the figure of the structure of the irregular testing fixture 1f of expression.In irregular testing fixture 1f, replace the optical filter leaning device 56 (with reference to Fig. 3) of irregular testing fixture 1e shown in Figure 16, as shown in figure 17, being provided with filter wheel 52 is the optical filter leaning device 56a of center rotation with optical filter turning axle 55a.Other structure is identical with Figure 16, indicates identical Reference numeral in the following description.The flow process of the inspection that the structure of optical filter leaning device 56a and the thickness that is undertaken by irregular testing fixture 1f are irregular is identical with second embodiment.

In irregular testing fixture 1f, with the 6th embodiment in the same manner, will be from the light of injection part 3 the incident angle θ 2 of relative substrate 9 be made as 10 °～40 °, can prevent that thus apparatus structure is complicated, simultaneously when the bigger thickness of detection thickness change is irregular, the mobility scale that can prevent whole thickness is included in the low sensitivity region, and it is irregular to detect thickness reliably.

In irregular testing fixture 1f, with second embodiment in the same manner, select optical filter 51a relatively from the catoptrical wave band (promptly selecting wave band) that sees through of substrate 9 by optical filter leaning device 56a precision than the highland adjustment.Consequently, select wave band to adjust by allowing, thereby can improve the irregular accuracy of detection of thickness corresponding to the characteristic of film 92, and then, can be in many irregular testing fixtures, precision makes than the highland and selects the wave band unanimity.In addition, owing to integrally change the inclination angle of a plurality of optical filter 51 relative light paths by 1 optical filter leaning device 56a, so can simplify the mechanism that a plurality of optical filters 51 is seen through the adjustment of wave band.

Then, the irregular testing fixture 1g at eighth embodiment of the invention describes.Figure 18 is the figure of the structure of the irregular testing fixture 1g of expression.As shown in figure 18, irregular testing fixture 1g, except that each structure, also have polariscope 6, when this polariscope 6 is configured in from substrate 9 to wavelength band switching mechanism on 5 the light path, optionally make from the S polarized light in the reflected light of film 92 to see through with irregular testing fixture 1e shown in Figure 16.Other structures are identical with Figure 16, indicate identical Reference numeral in the following description.

In irregular testing fixture 1g, with the 3rd embodiment in the same manner, the light that will be accepted at light accepting part 4 by polariscope 6 checks that based on the intensity distributions of S polarized light thickness is irregular as the S polarized light, it is irregular to detect thickness thus more accurately.In addition, because polariscope 6 is configured in (being on the light path of sensitive side) between substrate 9 and the linear sensor 41, so can prevent from the influence of the heat of light injection part 3 to polariscope 6.And then by polariscope 6 is configured between substrate 9 and the wavelength band switching mechanism 5, thereby the degree of freedom of the configuration of polariscope 6 uprises, so can prevent the structure complicated of locking apparatus.

Then, the irregular testing fixture 1h at ninth embodiment of the invention describes.Figure 19 is the figure of the structure of the irregular testing fixture 1h of expression.As shown in figure 19, in irregular testing fixture 1h, the polariscope 6 that the S polarized light is seen through is configured on the collector lens 42 and the light path between the linear sensor 41 of light accepting part 4.Other structures are identical with Figure 18, indicate identical Reference numeral in the following description.

In irregular testing fixture 1h, with the 8th embodiment in the same manner, check that based on the intensity distributions of S polarized light thickness is irregular, the thickness that can detect membrane 92 thus more accurately is irregular.In addition, because polariscope 6 is configured in (being on the light path of sensitive side) between substrate 9 and the linear sensor 41, so can prevent from the influence of the heat of light injection part 3 to polariscope 6.In irregular testing fixture 1h, special because polariscope 6 is configured between collector lens 42 and the linear sensor 41, so with the 4th embodiment in the same manner, can make polariscope 6 miniaturizations.

Then, the irregular testing fixture 1j at tenth embodiment of the invention describes.Figure 20 is the figure of the structure of the irregular testing fixture 1j of expression.As shown in figure 20, in irregular testing fixture 1j, the polariscope 6 that the S polarized light is seen through is configured on the lens pillar 33 and the light path between the substrate 9 of light injection part 3.Other structures are identical with Figure 18, indicate identical Reference numeral in the following description.

In irregular testing fixture 1j, with the 8th embodiment in the same manner, check that based on the intensity distributions of S polarized light thickness is irregular, the thickness that can detect membrane 92 thus more accurately is irregular.Particularly (for example forming the more coarse film 92 of surface ratio, the scattered light that light comprised that is reflected at substrate 9 align catoptrical ratio be 1% or the film 92 more than it) the thickness of substrate 9 when irregular, with the 5th embodiment in the same manner, by configuration polariscope 6 (being on the light path of emitting side) between light injection part 3 and substrate 9, compare with the situation of polariscope between substrate 9 and linear sensor 41 6 configuration (being on the light path of sensitive side), it is irregular to detect thickness more accurately.

More than, be illustrated at embodiments of the present invention, but the present invention is not limited in above-mentioned embodiment, can carry out various changes.

For example, objective table 2 can relatively move relative to light injection part 3, light accepting part 4 and wavelength band switching mechanism 5, also can be that objective table 2 is fixed, and light injection part 3, light accepting part 4 and wavelength band switching mechanism 5 move under the state that interfixes.

In light injection part 3, can replace quartz pushrod 32, and the fiber array that a plurality of optical fiber are arranged on linearity ground is set, from the light of Halogen lamp LED 31 by fiber array, thereby be transformed to Line of light.In addition, can replace Halogen lamp LED 31 and quartz pushrod 32, and be provided with that linearity ground arranges a plurality of luminous and diode are as the light source that penetrates Line of light.

In irregular testing fixture, contain the light time that the film 92 that forms at substrate 9 is given the wave band of bad influence at the light that penetrates from Halogen lamp LED 31, in that 9 light path setting does not make the optical filter of the light transmission of this wave band etc. from Halogen lamp LED 31 to substrate.In addition, when 92 pairs of infrared rays of the film on the upper surface 91 of substrate 9 have permeability, can replace the Halogen lamp LED 31 that penetrates white light, and the ultrared light source of ejaculation is set at light injection part 3.

Be made as constant by incident angle in entire upper surface 9 and simplify the irregular detection of thickness the light of relative substrate 9, from this viewpoint, preferably the linear sensor 41 that is relatively moved by relative substrate 9 is accepted to penetrate the reflected light of the Line of light of portion 3 from the light place, but shorten at needs under the situations such as shooting time of substrate 9, can replace linear sensor 41, and the two-dimensional CCD sensor is set at light accepting part 4.

Wavelength band switching mechanism 5 may not be configured in from substrate 9 to light accepting part on 4 the light path, for example, can be configured in from light injection part 3 to substrate on 9 the light path.In addition, the switching of the selection wave band that is undertaken by wavelength band switching mechanism 5 is not limited to the switching of a plurality of optical filters 51, a plurality of light sources of the light that penetrates different mutually a plurality of wave bands also can be set at light injection part 3, by a plurality of light sources of wavelength band switching mechanism 5 controls, switch thus from the wave band of the light of light injection part 3 ejaculations.

In the irregular testing fixture of above-mentioned embodiment, the thickness of film 92 is irregular to be detected by the extent of deviation of irregular test section 72 by the pixel value of each pixel of the two dimensional image of inspection upper surface 91, but the irregular detection of thickness also can be by the visual two dimensional image that is presented at the upper surface 91 of display etc. of operator, and carries out with reference to comparing with image.

The optical filter leaning device can be made the various structures beyond the said structure, for example, in the optical filter leaning device 56 of the the first, the 3rd to the 6th and the 8th to the tenth embodiment, end at the optical filter turning axle 55 of each optical filter 51 is connected with step motor, control rotary step motor by control part 8, thus can rotary optical optical filter 51, the inclination angle of automatically changing relative light path.In addition, the sense of rotation of the optical filter 51 that is undertaken by the optical filter leaning device can be the counter clockwise direction among Fig. 3 for example.

In the irregular testing fixture of the the 3rd to the 5th and the 8th to the tenth embodiment, only from accept this viewpoint of S polarized light at linear sensor 41, polariscope 6 can be configured in from light injection part 3 to linear sensor on 41 the light path Anywhere, for example can be configured in and select between optical filter 51a and the collector lens 42.

In the irregular testing fixture of first to the 5th embodiment, also be provided with: the second smooth injection part, its incident angle that penetrates relative substrate 9 is 10 °～40 ° a light, and second light accepting part, it accepts just can to realize that with a device high-precision test and thickness that small thickness changes change the bigger irregular reliable detection of thickness from the light of the second smooth injection part reflected light at substrate 9.

The irregular testing fixture of above-mentioned embodiment can be used in the dielectric film that forms on other the film, for example substrate 9 beyond the etchant resist and the irregular detection of thickness of conducting film, these films can be by formation such as method, for example vapour deposition method and chemical vapor-phase growing method (CVD:ChemicalVapor Deposition, chemical vapour deposition technique) except the coating of coating liquid, sputtering methods.In addition, irregular testing fixture can be used in the irregular inspection of thickness of the film that forms on other substrates such as semiconductor substrate.

At length describe and illustrated the present invention, but above-mentioned explanation is exemplary, and is not determinate.Therefore, only otherwise depart from the scope of the present invention, various deformation and mode can be arranged.

Claims

1. an irregular testing fixture checks that the thickness of the film that forms is irregular on substrate, it is characterized in that having:

Maintaining part, it keeps substrate;

The light injection part, it penetrates with respect to the interarea of the film that is formed with photopermeability of the aforesaid substrate light with 50 °～65 ° incident angle incident;

Sensor, it is received in the light of the specific wave band after above-mentioned interarea reflection of aforesaid substrate, and the light intensity of obtaining from the above-mentioned specific wave band of above-mentioned interarea distributes;

The wave band switching device shifter, it switches above-mentioned specific wave band between different mutually a plurality of wave bands.

2. irregular testing fixture as claimed in claim 1 is characterized in that,

Above-mentioned smooth injection part penetrates the light of the light that contains above-mentioned a plurality of wave bands;

Above-mentioned wave band switching device shifter has:

A plurality of optical filters, it optionally makes the light of above-mentioned a plurality of wave bands see through respectively;

The optical filter switching mechanism, it is by switching to other optical filter with being configured in above-mentioned a plurality of optical filters from the optical filter of above-mentioned smooth injection part to the light path of above-mentioned sensor, thereby changes above-mentioned specific wave band.

3. irregular testing fixture as claimed in claim 2 is characterized in that also having:

The first optical filter leaning device, it changes in above-mentioned a plurality of optical filter first optical filter with respect to the inclination angle of above-mentioned light path;

The second optical filter leaning device, it is different from above-mentioned first optical filter and changes in above-mentioned a plurality of optical filter second optical filter individually with respect to the inclination angle of above-mentioned light path;

Travel mechanism, it with respect to above-mentioned smooth injection part and the sensor, relatively moves above-mentioned maintaining part on the moving direction of the regulation of the above-mentioned interarea of aforesaid substrate,

Above-mentioned smooth injection part has:

Light source, its ejaculation contains the light of the light of above-mentioned a plurality of wave bands;

Optical system, it will be transformed to from the light of above-mentioned light source along above-mentioned interarea and perpendicular to the Line of light of above-mentioned moving direction, and the above-mentioned interarea that leads,

The sensor is a linear sensor, the mobile light intensity distribution that obtains synchronously and repeatedly from the above-mentioned specific wave band of the irradiation area of above-mentioned Line of light on aforesaid substrate of this linear sensor and above-mentioned maintaining part.

4. irregular testing fixture as claimed in claim 2 is characterized in that also having:

The optical filter leaning device, it integrally changes the inclination angle of above-mentioned a plurality of optical filter with respect to above-mentioned light path;

Above-mentioned smooth injection part has:

5. irregular testing fixture as claimed in claim 1 is characterized in that, also has polariscope, and this polariscope optionally makes the S polarized light with respect to above-mentioned film see through simultaneously on being configured in from above-mentioned smooth injection part to the light path of above-mentioned sensor.

6. irregular testing fixture as claimed in claim 5 is characterized in that above-mentioned polariscope is configured between aforesaid substrate and the sensor.

7. irregular testing fixture as claimed in claim 6 is characterized in that, also has collector lens, and this collector lens is configured in from aforesaid substrate to the light path of above-mentioned sensor, simultaneously the light of above-mentioned specific wave band is assembled to the sensor,

Above-mentioned polariscope is configured between above-mentioned collector lens and the sensor.

8. irregular testing fixture as claimed in claim 5 is characterized in that, above-mentioned polariscope is configured between above-mentioned smooth injection part and the aforesaid substrate.

9. irregular testing fixture as claimed in claim 8 is characterized in that, also has collector lens, and this collector lens is configured in from aforesaid substrate to the light path of above-mentioned sensor, simultaneously the light of above-mentioned specific wave band is assembled to the sensor.

10. irregular testing fixture as claimed in claim 1 is characterized in that, also has travel mechanism, this travel mechanism is on the moving direction of the regulation of the above-mentioned interarea of aforesaid substrate, with respect to above-mentioned smooth injection part and the sensor, above-mentioned maintaining part is relatively moved

Above-mentioned smooth injection part has:

Light source;

11. irregular testing fixture as claimed in claim 10 is characterized in that also having:

Optical filter, it is configured in from above-mentioned smooth injection part to the light path of above-mentioned sensor, makes the light transmission of above-mentioned specific wave band simultaneously;

The optical filter leaning device, it changes the inclination angle of above-mentioned optical filter with respect to above-mentioned light path.

12. irregular testing fixture as claimed in claim 11 is characterized in that, above-mentioned optical filter leaning device, with towards be parallel to above-mentioned wire direction of light the axle be that the center rotates above-mentioned optical filter.

13. irregular testing fixture as claimed in claim 1 is characterized in that, the above-mentioned film on the aforesaid substrate is coated on the above-mentioned interarea and forms by applying liquid.

14. an irregular testing fixture checks that the thickness of the film that forms is irregular on substrate, it is characterized in that having:

Maintaining part, it keeps substrate;

The light injection part, its penetrate with respect to aforesaid substrate be formed with photopermeability film interarea and with the light of 10 °～40 ° incident angle incident;

Sensor, it is received in the light of the specific wave band after above-mentioned interarea reflection of aforesaid substrate, and the light intensity of obtaining from the above-mentioned specific wave band of above-mentioned interarea distributes.

15. irregular testing fixture as claimed in claim 14 is characterized in that, also has the wave band switching device shifter, this wave band switching device shifter switches above-mentioned specific wave band between different mutually a plurality of wave bands;

Above-mentioned wave band switching device shifter has:

The optical filter switching mechanism, it switches to an optical filter on being configured in from above-mentioned smooth injection part to the light path of above-mentioned sensor in above-mentioned a plurality of optical filters other optical filter.

16. irregular testing fixture as claimed in claim 15 is characterized in that also having:

Above-mentioned smooth injection part has:

17. irregular testing fixture as claimed in claim 15 is characterized in that also having:

Above-mentioned smooth injection part has:

18. irregular testing fixture as claimed in claim 14 is characterized in that, also has polariscope, this polariscope optionally makes the S polarized light with respect to above-mentioned film see through simultaneously on being configured in from above-mentioned smooth injection part to the light path of above-mentioned sensor.

19. irregular testing fixture as claimed in claim 18 is characterized in that above-mentioned polariscope is configured between aforesaid substrate and the sensor.

20. irregular testing fixture as claimed in claim 19 is characterized in that, also has collector lens, this collector lens is configured in from aforesaid substrate to the light path of above-mentioned sensor, simultaneously the light of above-mentioned specific wave band is assembled to the sensor,

21. irregular testing fixture as claimed in claim 18 is characterized in that, above-mentioned polariscope is configured between above-mentioned smooth injection part and the aforesaid substrate.

22. irregular testing fixture as claimed in claim 21 is characterized in that, also has collector lens, this collector lens is configured in from aforesaid substrate to the light path of above-mentioned sensor, simultaneously the light of above-mentioned specific wave band is assembled to the sensor.

23. irregular testing fixture as claimed in claim 14 is characterized in that, also has travel mechanism, this travel mechanism is on the moving direction of the regulation of the above-mentioned interarea of aforesaid substrate, with respect to above-mentioned smooth injection part and the sensor, above-mentioned maintaining part is relatively moved

Above-mentioned smooth injection part has:

Light source;

24. irregular testing fixture as claimed in claim 23 is characterized in that also having:

25. irregular testing fixture as claimed in claim 24 is characterized in that, above-mentioned optical filter leaning device, with towards be parallel to above-mentioned wire direction of light the axle be that the center rotates above-mentioned optical filter.

26. irregular testing fixture as claimed in claim 14 is characterized in that, the above-mentioned film on the aforesaid substrate is coated on the above-mentioned interarea and forms by applying liquid.

27. an irregular inspection method is the irregular irregular inspection method of thickness of checking the film that forms on substrate, it is characterized in that having:

A) penetrate with respect to substrate be formed with photopermeability film interarea and with the operation of the light of 50 °～65 ° incident angle incident;

B) be received in the light of the specific wave band after the above-mentioned interarea reflection of aforesaid substrate, and obtain the operation that the light intensity from the above-mentioned specific wave band of above-mentioned interarea distributes;

C) the above-mentioned specific wave band of change, and carry out above-mentioned a) operation and b repeatedly) operation of operation.

28. irregular inspection method as claimed in claim 27, it is characterized in that, at above-mentioned b) the above-mentioned specific wave band accepted in the operation only before above-mentioned interarea reflection or see through polariscopic light afterwards, this polariscope is the polariscope that the S polarized light with respect to above-mentioned film is seen through.

29. irregular inspection method as claimed in claim 27 is characterized in that,

Before above-mentioned a) operation, also have: tilting is configured on the light path from the light injection part to sensor and makes the optical filter of the light transmission of above-mentioned specific wave band via aforesaid substrate, changes the operation of above-mentioned optical filter with respect to the inclination angle of above-mentioned light path;

In above-mentioned a) operation, from penetrating along the above-mentioned interarea and the Line of light of extending to above-mentioned film in the prescribed direction vertical with above-mentioned moving direction at the above-mentioned smooth injection part that on the moving direction of above-mentioned interarea, with respect to aforesaid substrate and relatively moves;

At above-mentioned b) in the operation, by the sensor that relatively moves with respect to aforesaid substrate and with above-mentioned smooth injection part, the light of the above-mentioned specific wave band of acceptance after by the reflection of above-mentioned film, and obtain the light intensity of irradiation area of the upwardly extending wire in side of the afore mentioned rules on the comfortable above-mentioned interarea to distribute repeatedly.

30. an irregular inspection method is the irregular irregular inspection method of thickness of checking the film that forms on substrate, it is characterized in that having:

A) penetrate with respect to substrate be formed with photopermeability film interarea and with the operation of the light of 10 °～40 ° incident angle incident;

B) be received in the light of the specific wave band after the above-mentioned interarea reflection of aforesaid substrate, and obtain the operation that the light intensity from the above-mentioned specific wave band of above-mentioned interarea distributes.

31. irregular inspection method as claimed in claim 30 is characterized in that,

At above-mentioned b) the above-mentioned specific wave band accepted in the operation only before above-mentioned interarea reflection or see through polariscopic light afterwards, this polariscope is the polariscope that the S polarized light with respect to above-mentioned film is seen through.

32. irregular inspection method as claimed in claim 30 is characterized in that,