WO2013002179A1 - Procédé d'évaluation de motif, appareil d'évaluation de motif et procédé de fabrication d'un dispositif à semi-conducteur - Google Patents

Procédé d'évaluation de motif, appareil d'évaluation de motif et procédé de fabrication d'un dispositif à semi-conducteur Download PDF

Info

Publication number
WO2013002179A1
WO2013002179A1 PCT/JP2012/066154 JP2012066154W WO2013002179A1 WO 2013002179 A1 WO2013002179 A1 WO 2013002179A1 JP 2012066154 W JP2012066154 W JP 2012066154W WO 2013002179 A1 WO2013002179 A1 WO 2013002179A1
Authority
WO
WIPO (PCT)
Prior art keywords
wafer
pattern
holding
unit
light
Prior art date
Application number
PCT/JP2012/066154
Other languages
English (en)
Japanese (ja)
Inventor
義彦 藤森
佐藤　立美
Original Assignee
株式会社ニコン
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社ニコン filed Critical 株式会社ニコン
Publication of WO2013002179A1 publication Critical patent/WO2013002179A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/68—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for positioning, orientation or alignment
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/88—Investigating the presence of flaws or contamination
    • G01N21/95—Investigating the presence of flaws or contamination characterised by the material or shape of the object to be examined
    • G01N21/9501—Semiconductor wafers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/88—Investigating the presence of flaws or contamination
    • G01N21/95—Investigating the presence of flaws or contamination characterised by the material or shape of the object to be examined
    • G01N21/956—Inspecting patterns on the surface of objects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/47—Scattering, i.e. diffuse reflection
    • G01N21/4788—Diffraction
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
    • H01L22/10—Measuring as part of the manufacturing process
    • H01L22/12—Measuring as part of the manufacturing process for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001—Technical content checked by a classifier
    • H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Definitions

  • the present invention relates to a substrate evaluation method and apparatus, and further to a semiconductor device manufacturing method.
  • a wafer holder In order to hold the wafer, it is common to vacuum-suck the entire back surface of the wafer with a wafer holder.
  • a wafer holder When the surface of the wafer held by such a wafer holder is irradiated with infrared rays and an image based on diffracted light emitted from the wafer surface is acquired as an inspection image of the wafer, a part of the irradiated infrared rays reaches the opposite side of the wafer. It may be transmitted and reflected or scattered by a wafer holder (for example, an edge portion of the suction groove).
  • reflected and scattered light from the wafer holder (for example, the edge portion of the suction groove) reaches the camera of the light receiving system and becomes noise in the inspection image, and the inspection accuracy is improved. May decrease.
  • the present invention has been made in view of such a problem, and an object thereof is to provide an evaluation method, an evaluation apparatus, and a semiconductor device manufacturing method capable of highly accurate evaluation or inspection.
  • the pattern evaluation method holds a substrate at a first holding position of a substrate having a pattern, illuminates the pattern with a predetermined posture with inspection light, and Receiving the light diffracted by the first detection and outputting a detection signal, holding the substrate at a second holding position different from the first holding position of the substrate, Illuminate with the inspection light as the posture, receive the light from the pattern and output a detection signal, and perform a second detection, based on the first detection result and the second detection result The pattern is evaluated.
  • the method of manufacturing a semiconductor device includes exposing an etching pattern on the surface of the substrate, performing etching on the surface of the substrate in accordance with the exposed etching pattern, Inspecting the etched substrate, and the inspection is performed using the pattern evaluation method according to the present invention.
  • the pattern evaluation apparatus also includes a detection unit that receives light from a pattern in a predetermined posture and outputs a detection signal, and a first holding unit of the substrate having the pattern.
  • An evaluation unit that evaluates the pattern based on a holding member capable of holding a substrate, and a detection signal when held in the first holding state and a detection signal when held in the second holding state And.
  • a highly accurate pattern can be evaluated or inspected.
  • (A) is a bottom view of the wafer holder which concerns on 1st Embodiment
  • (b) is a bottom view which shows the state which changed the holding position of the wafer holder with respect to (a). It is a flowchart for demonstrating the back surface diffraction test
  • (A) is an enlarged view when the wafer is viewed from above, and (b) is an enlarged cross-sectional view of the wafer.
  • (A) is the cross-sectional enlarged view of the wafer in the state where the middle of the hole has expanded
  • (b) is the cross-sectional enlarged view of the wafer in a state where the deep part of the hole is tapered.
  • (A) is a top view of the wafer holder which concerns on 2nd Embodiment
  • (b) is a fragmentary sectional view of the wafer holder which concerns on 2nd Embodiment.
  • (A) is a top view of the wafer holder which concerns on 2nd Embodiment
  • (b) is a top view which shows the state which changed the holding position of the wafer holder with respect to (a).
  • (A) is a bottom view of the wafer holder which concerns on 2nd Embodiment
  • (b) is a bottom view which shows the state which changed the holding position of the wafer holder with respect to (a). It is a sectional side view of the wafer holder concerning a 2nd embodiment.
  • (A) is a top view of the wafer holder which concerns on 3rd Embodiment
  • (b) is a fragmentary sectional view of the wafer holder which concerns on 3rd Embodiment.
  • It is the schematic of the inspection apparatus which concerns on 4th Embodiment. It is a flowchart which shows the manufacturing method of a semiconductor device.
  • the inspection apparatus of the first embodiment is shown in FIG. 1, and this apparatus inspects (or evaluates) the entire front or back surface of the wafer W, which is a silicon substrate.
  • the vertical and horizontal directions in a plane parallel to the paper surface are defined as the Z axis and the X axis, respectively, and the direction perpendicular to the paper surface is defined as the Y axis.
  • the inspection apparatus 1 according to the first embodiment includes a wafer holder 10 that holds a wafer W formed in a substantially disk shape. The wafer W is placed on the wafer holder 10 and is fixedly held by vacuum suction.
  • the tilt mechanism 19 provided in the wafer holder 10 tilts the wafer W held by the wafer holder 10 about an axis parallel to the surface of the wafer W (an axis extending in the Y-axis direction) (that is, incident illumination light). Tilting about an axis perpendicular to the surface, hereinafter referred to as tilting as appropriate), and the incident angle of the illumination light can be adjusted.
  • the inspection apparatus 1 further receives a first illumination unit 20 that irradiates illumination light (inspection light) as parallel light onto the surface of the wafer W held by the wafer holder 10, and illumination light irradiation from the first illumination unit 20.
  • a first detection unit 30 that detects light (diffracted light including the 0th order) reflected by the surface of the wafer W (and a pattern provided on the surface), and illumination light on the back surface of the wafer W held by the wafer holder 10
  • Second illumination unit 40 that irradiates (inspection light) as parallel light, and light (diffracted light including 0th order) reflected by the back surface of wafer W when irradiated with illumination light from second illumination unit 40
  • the second detection unit 50 for detecting, the control unit 60 for controlling the apparatus, the image processing unit 61 for performing image processing, the display unit 62 for performing image display, and the processing result of the image processing unit 61 to an external computer or the like
  • an output unit 63 for outputting
  • the tilt mechanism 19 is configured so that light that is diffracted (including 0th order) through the wafer W when the illumination angle of the wafer W is irradiated with illumination light from the second illumination unit 40 is detected by the first detection unit. It can adjust so that 30 may enter. In such a state, the first detection unit 30 can also detect the light that is transmitted through the wafer W and diffracted. Similarly, the second detection unit 50 can detect light diffracted (including 0th order) through the wafer W when irradiated with illumination light from the first illumination unit 20.
  • the first illumination unit 20 includes a first illumination unit 21 that emits illumination light, and a first illumination-side concave mirror 25 that reflects the illumination light emitted from the first illumination unit 21 toward the surface of the wafer W.
  • the first lighting unit 21 includes a first light source unit 22 such as a metal halide lamp, a mercury lamp, or a halogen lamp, a wavelength selection filter that transmits light having a predetermined wavelength among the light from the first light source unit 22, and a transmitted light
  • a first dimming unit 23 having a transmittance variable ND (neutral density) filter for adjusting the intensity, and a first light guide for guiding light from the first dimming unit 23 to the first illumination side concave mirror 25 as illumination light
  • a fiber 24 is a fiber 24.
  • the light from the 1st light source part 22 passes the 1st light control part 23, and the illumination light of the wavelength and intensity
  • the first detection unit 30 is mainly composed of a first light-receiving side concave mirror 31 and a first imaging unit 35 disposed to face the wafer holder 10, and emitted light collected by the first light-receiving side concave mirror 31. Reaches the imaging surface of the first imaging unit 35 and an image of the wafer W is formed.
  • the first imaging unit 35 includes an objective lens and an image sensor (not shown), and generates an image signal (detection signal) by photoelectrically converting an image of the wafer W formed on the imaging surface of the image sensor.
  • the image signal is output to the image processing unit 61 via the control unit 60.
  • the second illumination unit 40 includes a second illumination unit 41 that emits illumination light, and a second illumination-side concave mirror 45 that reflects the illumination light emitted from the second illumination unit 41 toward the back surface of the wafer W. Configured.
  • the second lighting unit 41 has the same configuration as that of the first lighting unit 21 and includes a second light source unit 42, a second dimming unit 43, and a second light guide fiber 44.
  • the light from the second light source unit 42 passes through the second dimming unit 43, and the illumination light having the wavelength and intensity adjusted by the second dimming unit 43 is transmitted from the second light guide fiber 44 to the second illumination side concave mirror. It is emitted to 45 and becomes divergent light. Since the emission part of the second light guide fiber 44 is disposed on the focal plane of the second illumination side concave mirror 45, the illumination light emitted from the second light guide fiber 44 to the second illumination side concave mirror 45 is the second illumination.
  • the side concave mirror 45 irradiates the entire back surface of the wafer W held by the wafer holder 10 as parallel (telecentric) light. The incident angle and the emission angle of the illumination light with respect to the wafer W can be adjusted by tilting the wafer holder 10 and changing the mounting angle of the wafer W.
  • the emitted light (diffracted light, specularly reflected light, etc.) from the back surface of the wafer W is detected by the second detection unit 50.
  • the second detection unit 50 is mainly configured by a second light-receiving side concave mirror 51 and a second imaging unit 55 which are arranged to face the lower side of the wafer holder 10, and the parallel emitted light reflected on the back surface of the wafer W is second.
  • the light is collected by the light receiving side concave mirror 51 and reaches the imaging surface of the second imaging unit 55, and an image of the wafer W is formed.
  • the second imaging unit 55 includes an objective lens, an image sensor, and the like (not shown), and generates an image signal (detection signal) by photoelectrically converting an image of the wafer W formed on the imaging surface of the image sensor.
  • the image signal is output to the image processing unit 61 via the control unit 60.
  • the control unit 60 controls the wafer holder 10, the tilt mechanism 19, the first and second illumination units 21, 41, the first and second imaging units 35, 55, and the like, respectively.
  • the image processing unit 61 generates an image (digital image) of the wafer W based on the image signal from the first imaging unit 35 or the second imaging unit 55.
  • the wafer holder 10 according to the first embodiment is disposed on the frame 11, an annular frame 11, eight arms 12 a to 12 h that are formed in a plate shape capable of supporting the wafer W and suck and hold the wafer W, and the frame 11. And eight arm driving portions 13a to 13h for holding the eight arm portions 12a to 12h in a rotatable manner.
  • the frame portion 11 is formed in an annular shape having a diameter larger than that of the wafer W, and is configured to be tiltable together with the eight arm portions 12a to 12h and the arm drive portions 13a to 13h by a tilt mechanism 19 (see FIG. 1). .
  • the eight arm portions 12a to 12h and the eight arm driving portions 13a to 13h are paired with the same alphabetical code, and are equally spaced along the circumferential direction of the frame portion 11 (at 45 degree intervals). Arranged.
  • the arm portions 12a, 12c, 12e, and 12g may be collectively referred to as a first arm portion group
  • the arm portions 12b, 12d, 12f, and 12h may be collectively referred to as a second arm portion group.
  • the arm drive units 13a, 13c, 13e, and 13g may be collectively referred to as a first arm drive unit group
  • the arm drive units 13b, 13d, 13f, and 13h may be collectively referred to as a second arm drive unit group. .
  • the eight arm portions 12a to 12h are disposed so as to extend toward the inner diameter side of the frame portion 11 by the eight arm driving portions 13a to 13h, and suck and hold the wafer W in an area surrounded by the frame portion 11. It is like that. Therefore, a groove (not shown) for vacuum suction is formed in a portion of each arm portion 12a to 12h that contacts the wafer W.
  • the first arm portion group and the second arm portion group are located on the inner diameter side of the frame portion 11 so as to be capable of sucking and holding the wafer W, and on the retracted position positioned on the outer diameter side of the frame portion 11. It can be rotationally displaced.
  • the arm portion that is located at the retracted position and extends outside the frame portion 11 is It rotates from the position toward the inside of the frame part 11 and rotates toward the suction position located on the inner diameter side of the frame part 11.
  • each arm drive part may be comprised using a servomotor, for example, and may be comprised using a rotary actuator. Alternatively, other configurations can be adopted as necessary.
  • Each arm drive unit is driven in response to a command from the control unit 60 based on a recipe (a sequence stored in accordance with the type of inspection of the wafer W) stored in a storage unit built in the control unit 60. The Unless otherwise specified, each drive and each process is performed based on a recipe stored in a storage unit built in the control unit 60.
  • the control unit 60 is connected to an input device (not shown) so that the operator can select one or both of the front surface diffraction inspection and the rear surface diffraction inspection of the wafer W using the input device and register it in the recipe. It is configured. In addition, manual operation not based on the recipe is also possible.
  • the first detection unit 30 and the second detection unit 50 are described in the same plane, it seems to interfere with each of the arm units 12a to 12h swung to the retracted position.
  • the first light-receiving side concave mirror 31 is tilted in the direction perpendicular to the paper surface so that the first imaging unit 35 is at the back of the paper surface, and the second light-receiving side is disposed so that the second image capturing unit 55 is in front of the paper surface. If the concave mirror 51 is disposed so as to be inclined in the direction perpendicular to the paper surface, the interference between the two will be eliminated and the arms 12a to 12h can be swung.
  • a wafer W inspection / evaluation method using the inspection apparatus 1 configured as described above will be described.
  • the wafer W to be inspected is transferred onto the wafer holder 10 by a transfer device (not shown) so that the surface (the surface on which the pattern to be inspected is provided) faces upward (see S11 in FIG. 3).
  • the wafer W is aligned on the wafer holder 10 by the alignment mechanism (not shown) on the basis of a reference mark (notch, orientation flat, etc.) provided on the outer edge by an alignment mechanism (not shown) during the transfer.
  • the wafer holder 10 rotates and displaces the first arm unit group to the suction position by the operation of the first arm driving unit group and the second arm driving unit group.
  • the wafer W is sucked and held by the first arm portion group in a state where the second arm portion group is rotationally displaced to the retracted position (hereinafter referred to as a first holding state for convenience) (FIG. 3). (See S12).
  • each part of the inspection apparatus (wafer holder 10, first arm driving unit group, second arm driving unit group, tilt mechanism 19, first and second illumination units 21, 41, first and second imaging units 35, 55, etc.) ) Is driven in response to a command from the control unit 60.
  • illumination light having a predetermined wavelength for example, wavelength of 546 nm
  • the reflected illumination light becomes parallel light and is irradiated on the entire surface of the wafer W held by the wafer holder 10 in the first holding state.
  • tilt angle tilt angle
  • Diffracted light from the pattern can be received by the first detection unit 30 to form an image of the wafer W.
  • the repetitive direction of the repetitive pattern A on the wafer W is obtained using the alignment mechanism (not shown) and the information of the repetitive pattern A input and stored in advance, and the illumination direction on the surface of the wafer W (first The wafer W is arranged such that the direction from the illumination unit 20 toward the first detection unit 30) and the pattern A repetition direction match.
  • the wafer W is tilted by the tilt mechanism 19 so that the pitch of the pattern A is P, the wavelength of the illumination light applied to the surface of the wafer W is ⁇ , the incident angle of the illumination light is ⁇ 1, and the next time Setting is made so that the following Expression 1 is satisfied when the outgoing angle of the folded light is ⁇ 2.
  • the diffracted light generated in the repeated pattern A of the wafer W and emitted from the front surface side of the wafer W is collected by the first light receiving side concave mirror 31 and reaches the imaging surface of the first imaging unit 35, An image (image by diffracted light) is formed.
  • an image of the wafer W can be obtained by setting the tilt angle of the wafer W and the pattern repeat direction to a predetermined posture with respect to the illumination light.
  • the image sensor of the first imaging unit 35 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is transmitted to the image processing unit via the control unit 60. To 61.
  • the image processing unit 61 generates an image (digital image) of the wafer W based on the image signal input from the first imaging unit 35. Further, when the image processing unit 61 generates an image (digital image) of the wafer W, the image data of the non-defective wafer (in the surface diffraction inspection) stored in the image data of the generated wafer W and a database (not shown) ( Compared with the reference pattern), the wafer W is inspected for abnormalities (defects) or the pattern is evaluated. The inspection of the wafer W is performed for each chip area (area corresponding to one semiconductor device as a product), and the signal intensity (luminance value) of the wafer W to be inspected and the signal intensity (luminance value) of a non-defective wafer.
  • the present teaching is not limited to this, and the inspection may be performed for each of a plurality of chip regions as necessary. Alternatively, a region narrower than one chip region may be designated and the above inspection may be performed on that region. Then, the result of the surface diffraction inspection by the image processing unit 61 and the image of the wafer W at that time are output and displayed on the display unit 62 and also output to an external computer or the like by the output unit 63.
  • the acquired image becomes an image having brightness according to the intensity of the diffracted light (hereinafter referred to as a diffracted image).
  • the intensity of the diffracted light changes according to the distribution of diffraction efficiency, and if the regularly formed pattern A is made uniform, no local change in diffraction efficiency will occur.
  • the shape of the pattern A in a partial region changes, the diffraction efficiency of the region changes, and as a result, the brightness of the diffraction image in the corresponding region changes. Changes can be detected.
  • the pattern change is a change in the line width (hole diameter), hole shape, or cross-sectional shape of the pattern A.
  • the distance (pixel size) on the wafer W corresponding to one pixel of the diffraction image captured and acquired by the first imaging unit 35 (or the second imaging unit 55) is, for example, 300 ⁇ m, and is based on the dimension of the pattern A and the repetition pitch.
  • the brightness of each pixel in the diffraction image corresponds to the average intensity of the diffracted light from the pattern of the corresponding region on the wafer W. If the pattern A of the wafer W is not normally formed due to a defect in an exposure apparatus or an etching apparatus that forms a pattern, the entire pattern in a region having a certain area is deformed in the same manner, so the pixel size is the dimension of the pattern A. Even if the pitch is larger than the repetition pitch, it is possible to detect an abnormality (defect) in the corresponding region.
  • the first imaging unit 35 causes the diffraction image to be emitted. Can be obtained. From this diffraction image, as described above, the abnormality (defect) of the pattern A can be detected.
  • the only abnormality that can be detected is an abnormality near the surface of the wafer W. That is, the abnormality that can be detected includes an abnormality in the hole diameter near the surface of the wafer W, an abnormality in the hole shape, and an abnormality in the cross-sectional shape of the hole near the surface of the wafer W.
  • FIG. 5 is an enlarged view of a portion of the wafer W viewed from above, and FIG. 5B is an enlarged cross-sectional view of the wafer W.
  • the hole diameter is 2 ⁇ m
  • the hole pitch is 4 ⁇ m
  • the hole depth is 20 ⁇ m.
  • the thickness of the wafer W is 725 ⁇ m, and the thickness of the wafer W is omitted in FIG. Further, in FIG. 5, the silicon portion is indicated by hatching and the hole portion is indicated by white.
  • FIG. 6 shows an example in which the holes constituting the pattern A are not formed normally.
  • FIG. 6A shows a case where the middle of the hole is swollen
  • FIG. 6B shows a case where the deep part of the hole is tapered. If it becomes such a shape, it interferes with the subsequent forming process and the function of the finished TSV, and must be detected by inspection.
  • infrared illumination light for example, light having a wavelength of 1100 nm
  • the diffracted light detected by the first imaging unit 35 is used. Since diffracted light from a deep hole is also included, it is possible to detect an abnormality (defect) in the deep hole.
  • the depth at which the illumination light reaches the wafer W can be changed by changing the illumination wavelength.
  • an abnormality when the illumination wavelength in the infrared region is relatively short (that is, the depth at which the illumination light reaches is relatively shallow), no abnormality is detected, and the illumination wavelength in the infrared region is relatively long (that is, the arrival of illumination light) If an abnormality is detected when the depth of the wafer W is relatively deep), it is understood that there is an abnormality in a deep portion of the wafer W. For example, as shown in FIG. 6B, an abnormality (defect) in which a deep hole is tapered may be considered.
  • the second illumination unit 40 is used to illuminate the back surface of the wafer W from the back surface side of the wafer W, and the diffracted light emitted from the back surface of the wafer W is second.
  • An inspection (hereinafter referred to as back-surface diffraction inspection) performed by detection by the detection unit 50 is effective. That is, if the back surface diffraction inspection of the wafer W is performed using illumination light that is permeable to silicon (infrared light having a wavelength of 700 nm or more is preferable, for example, light having a wavelength of 1100 nm), an abnormality (defect) in a deep part of the hole is detected. can do.
  • the illumination light passes through the silicon on the back side of the wafer W and is diffracted at the boundary (surface) between the silicon portion and the hole portion of the wafer W. This is because light (diffraction phenomenon) occurs.
  • light diffracted by being illuminated by the second illumination unit 40 from one surface of the front and back surfaces of the wafer W is transmitted in the component that reflects in one surface direction and in the other surface direction (in this case, the pattern is like a diffraction grating).
  • the component which acts on is generated.
  • an inspection hereinafter referred to as a transmission diffraction inspection
  • the first detection unit 30 detects the light transmitted and diffracted to the other surface is also effective.
  • illumination light having a predetermined wavelength for example, wavelength of 1100 nm
  • the reflected illumination light is converted into parallel light and applied to the entire back surface of the wafer W held by the wafer holder 10 in the first holding state (S13).
  • the tilt angle of the wafer W held on the wafer holder 10 based on the wavelength of the illumination light emitted from the second illumination unit 41, diffraction from a regularly formed repetitive pattern of a predetermined pitch is performed.
  • the light can be received by the second detection unit 50 to form an image of the wafer W (S14).
  • the repetitive direction of the repetitive pattern A on the wafer W is obtained using the alignment mechanism (not shown) and the information of the repetitive pattern A input and stored in advance, and the illumination direction on the back surface of the wafer W (second)
  • the wafer W is arranged so that the direction from the illumination unit 40 toward the second detection unit 50 and the pattern A repetition direction coincide with each other, and the wafer W is tilted (tilted) by the tilt mechanism 19. 1 is set so as to satisfy 1 (matching diffraction conditions).
  • the diffracted light that is generated by the repetitive pattern A of the wafer W and is emitted (reflected) from the back surface side is collected by the second light receiving side concave mirror 51 and reaches the image pickup surface of the second image pickup unit 55 to be in the first holding state.
  • An image of the wafer W held by the wafer holder 10 (image by diffracted light) is formed.
  • the image sensor of the second imaging unit 55 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is transmitted to the image processing unit via the control unit 60. It outputs to 61 (S15).
  • the wafer holder 10 moves the first arm unit group to the retracted position by the first arm driving unit group as shown in FIG.
  • the second arm in a state where the second arm drive unit group is rotationally displaced to the suction position by the second arm drive unit group (hereinafter referred to as a second holding state for convenience).
  • the wafer W is sucked and held by the group of parts (S16).
  • the second arm drive unit group causes the second arm unit group to be pivotally displaced from the retracted position to the suction position, and then the first arm drive unit group retracts the first arm unit group from the suction position. Rotate to position.
  • the holding position of the wafer holder 10 with respect to the wafer W can be changed (to a position rotated by 45 degrees around the rotational symmetry axis of the frame portion 11) without moving the wafer W (while maintaining the posture).
  • illumination light having the same wavelength as that when the wafer W is held in the first holding state is emitted from the second illumination unit 41 to the second illumination side concave mirror 45, and the illumination light reflected by the second illumination side concave mirror 45 is emitted.
  • the parallel light is irradiated onto the entire back surface of the wafer W held by the wafer holder 10 in the second holding state (S17).
  • the tilt angle (tilt angle) of the wafer W held by the wafer holder 10 and the repetition direction of the illumination light and the repeating pattern are changed. (The posture of the pattern on the wafer W is maintained), so that the second detection unit 50 receives diffracted light under the same conditions as when the wafer W is held in the first holding state. Can be formed.
  • the arm portions 12a to 12h of the first arm portion group and the second arm portion group are arranged at intervals of 45 degrees, respectively, so that the wafer W can be divided into four in either the first holding state or the second holding state. Deflection does not occur because it is held in place.
  • the thickness of the wafer W is thinner than the above example (725 ⁇ m) (for example, 100 ⁇ m)
  • the holding portions 312a to 312h of the arm portions 12a 'to 12h' can be made triangular so that the occurrence of deflection can be suppressed.
  • the diffracted light generated from the repetitive pattern A of the wafer W and emitted from the back surface side is condensed by the second light receiving side concave mirror 51 and reaches the image pickup surface of the second image pickup unit 55, and the wafer holder 10 in the second holding state.
  • An image of the wafer W (image by diffracted light) held on is formed.
  • the image sensor of the second imaging unit 55 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is transmitted to the image processing unit via the control unit 60. It outputs to 61 (S18).
  • the image processing unit 61 is based on the image signal input from the second imaging unit 55 in the first holding state and the second holding state, respectively. Then, an image (digital image) of the wafer W is generated. At this time, in the image of the wafer W held by the wafer holder 10 in the first holding state, the portion adsorbed and held by the first arm portion group and the vicinity thereof are excluded from the inspection target region because they are shadows of these arms. . Further, in the image of the wafer W held on the wafer holder 10 in the second holding state, the portion adsorbed and held by the second arm portion group and the vicinity thereof are excluded from the inspection target area because they are shadows of these arms.
  • the image (digital image) of the wafer W is generated by combining the image signal of the non-holding portion excluding the portion (and the vicinity thereof) held by each arm portion in the wafer W (S19).
  • the switching from the first holding state to the second holding state is performed while maintaining the posture of the wafer W, the image of the wafer W held on the wafer holder 10 in the first holding state and the second holding state are maintained.
  • the image of the wafer W held on the wafer holder 10 in the state is basically not relatively displaced, but if necessary, an image of the non-holding portion of the wafer W held on the wafer holder 10 in the first holding state. Alignment may be performed with reference to a pattern existing in an overlapping area between the image of the non-holding portion of the wafer W held by the wafer holder 10 in the second holding state. In the synthesis, the image corresponding to the holding portion (and its vicinity) in one image adopts the image of the other non-holding portion, and the average value of the two images is used in the overlapping region of the non-holding portion. .
  • a weighted average value of two images may be further employed. For example, the weight of an image is decreased near the holding portion of one image (the other weight is increased), and the weight is increased far from the holding portion of one image (the other is decreased). If a change in weight is applied, an image of the wafer W without an unnatural signal change based on a subtle difference in brightness between two images due to imaging noise or the like can be obtained.
  • the image processing unit 61 When the image processing unit 61 generates a composite image of the wafer W, as in the case of the surface diffraction inspection, the non-defective wafer (in the back surface diffraction inspection) stored in the image data and database (not shown) of the generated wafer W. The image data is compared with each other to inspect whether there is an abnormality (defect) in the wafer W or to evaluate the pattern (S20). Then, the result of the back surface diffraction inspection by the image processing unit 61 and the image of the wafer W at that time are output and displayed on the display unit 62 and also output to an external computer or the like by the output unit 63.
  • the backside diffraction inspection similarly to the surface diffraction inspection, by changing the illumination wavelength, an inspection is performed under a plurality of conditions in which the depth at which the illumination light reaches the wafer W is changed. By combining, it is possible to determine the type of abnormality (defect) in the wafer W. However, it is difficult to distinguish the top and bottom of the hole except for a wafer (for example, 100 ⁇ m thick) thinned by back grinding. When the wafer thickness is 725 ⁇ m and the hole depth is 20 ⁇ m as in the above example, the distance from the wafer back surface to the vicinity of the hole opening is 725 ⁇ m. This is because the distance from the hole bottom to the hole bottom is 705 ⁇ m, and the difference is about 20 ⁇ m. In that case, inspection can be performed by performing more precise wavelength control (for example, accuracy of ⁇ 1 ⁇ m).
  • the first to eighth arm driving units 13a to 13h (holding position changing units) that change the holding position of the wafer holder 10 with respect to the wafer W are provided.
  • the image of the changed wafer W can be acquired, and the back surface diffraction inspection over the whole back surface side of the wafer W becomes possible.
  • it is possible to perform the back surface diffraction inspection of substantially the entire wafer by holding the wafer W by holding the wafer by sandwiching the edge portion of the wafer W. Since the wafer is held, “deflection” due to the weight of the wafer W occurs, and the accuracy of the diffraction inspection deteriorates.
  • the arm portions of the first arm portion group and the second arm portion group are arranged at 45 degree intervals, respectively, in either the first holding state or the second holding state.
  • “deflection” due to the weight of the wafer W as in the case of the edge grip does not occur. Therefore, it is possible to perform a back surface diffraction inspection with high accuracy using illumination light having permeability to the wafer W without lowering the uniformity of the illumination angle and the light receiving angle within the wafer surface.
  • the repetition direction (posture) of the pattern A with respect to the second illumination unit 40 and the second detection unit 50 can be kept constant, and the wafer holder 10 can be held. Regardless of the position, it is possible to detect the diffracted light under the same conditions and perform a highly accurate back surface diffraction inspection (inspection or evaluation of the wafer W).
  • the image processing unit 61 holds the image signal input from the second imaging unit 55 in each arm unit in the wafer W in the first holding state and the second holding state (that is, a plurality of substrate holding conditions).
  • the back surface diffraction inspection over the entire back side of the wafer W is more reliably performed. be able to.
  • the wafer W can be moved without changing the posture of the wafer W. Since the configuration is such that the holding position of the wafer holder 10 is changed, the holding position can be changed without sucking the front surface side (surface opposite to the attracted surface) of the wafer W. Thereby, the holding position can be changed without damaging the surface side of the wafer W.
  • the front surface diffraction inspection and the back surface diffraction inspection of the wafer W not only the front surface diffraction inspection and the back surface diffraction inspection of the wafer W but also a transmission diffraction inspection can be performed.
  • illumination light having a predetermined wavelength for example, wavelength of 1100 nm
  • the reflected illumination light becomes parallel light and is irradiated on the entire surface of the wafer W held by the wafer holder 10 in the first holding state.
  • the tilt angle (tilt angle) of the wafer W held by the wafer holder 10 based on the wavelength of the illumination light emitted from the first illumination unit 21, it is diffracted by the repetitive pattern A of the wafer W.
  • Diffracted light transmitted to the back side opposite to the side illuminated with the illumination light (hereinafter referred to as transmitted diffracted light) can be received by the second detection unit 50 to form an image of the wafer W.
  • the tilt mechanism 19 tilts (tilts) the wafer W, and a rotating device (not shown) rotates (tilts) the entire second detection unit 50 about an axis passing through the surface of the wafer W, so that illumination light is incident.
  • the angle and the emission angle (detection angle) of the transmitted diffracted light it is possible to guide the transmitted diffracted light of a desired specific order at the desired incident angle to the second detection unit 50.
  • the tilt axis of the tilt mechanism 19 and the rotation axis for rotating the second detection unit 50 are parallel. Further, the repeating direction of the repeating pattern provided on the wafer W to be placed is substantially orthogonal to the tilt axis of the tilt mechanism 19 and the rotation axis for rotating the second detection unit 50.
  • the transmitted diffracted light transmitted to the back surface side of the wafer W is collected by the second light receiving side concave mirror 51 and reaches the image pickup surface of the second image pickup unit 55, and the wafer W held by the wafer holder 10 in the first holding state.
  • An image image by diffracted light
  • the image sensor of the second imaging unit 55 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is transmitted to the image processing unit via the control unit 60.
  • the control unit 60 To 61.
  • the wafer holder 10 When an image of the wafer W held by the wafer holder 10 in the first holding state is picked up, the wafer holder 10 sucks and holds the wafer W in the second holding state by the operation of the first to eighth arm driving units 13a to 13h. Switching from the first holding state to the second holding state is performed in the same manner as in the first embodiment described above.
  • illumination light having the same wavelength as that when the wafer W is held in the first holding state is emitted from the first illumination unit 21 to the first illumination side concave mirror 25, and the illumination light reflected by the first illumination side concave mirror 25 is emitted.
  • the parallel light is irradiated onto the entire surface of the wafer W held by the wafer holder 10 in the second holding state.
  • the amount of tilt (tilt angle) of the wafer W held by the wafer holder 10 does not change only by changing the holding position of the wafer holder 10 with respect to the wafer W (the arm part displaced to the suction position), so the first holding state
  • the transmitted diffracted light under the same conditions as when the wafer W is held can be received by the second detector 50 to form an image of the wafer W.
  • the transmitted diffracted light transmitted to the back side of the wafer W is collected by the second light receiving side concave mirror 51 and reaches the imaging surface of the second imaging unit 55, and the wafer W held by the wafer holder 10 in the second holding state. An image (image by diffracted light) is formed.
  • the image sensor of the second imaging unit 55 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is transmitted to the image processing unit via the control unit 60. To 61.
  • the image processing unit 61 When an image of the wafer W held by the wafer holder 10 in the second holding state is captured, the image processing unit 61 generates a composite image (digital image) of the wafer W in the same manner as in the first embodiment described above. The wafer W is inspected for abnormalities (defects) or the pattern is evaluated. Then, the result of the transmission diffraction inspection by the image processing unit 61 and the image of the wafer W at that time are output and displayed on the display unit 62 and output to an external computer or the like by the output unit 63.
  • the second illumination unit 40 may irradiate the back surface of the wafer W with illumination light
  • the first detection unit 30 may detect the transmitted diffracted light transmitted to the front surface side of the wafer W.
  • the image processing unit 61 is a non-holding portion excluding a portion (and the vicinity thereof) held by each arm portion of the wafer W held by the wafer holder 10 in the first holding state.
  • the image signal of the wafer W is synthesized by combining the image signal and the image signal of the non-holding portion excluding the portion (and the vicinity thereof) held by each arm portion in the wafer W held by the wafer holder 10 in the second holding state. (Digital image) is generated, and the presence or absence of an abnormality (defect) in the wafer W is inspected.
  • the present teaching is not limited to this.
  • the wafer holder in the second holding state is inspected for the presence (abnormality) of the non-holding portion in the wafer W. 10
  • the presence or absence of an abnormality (defect) in the non-holding portion of the wafer W is inspected, and the two inspection results are combined (specifically, determined to be abnormal) Or, a logical sum (OR) of the inspection results may be taken).
  • the eight arm portions 12a to 12h are provided, but the present teaching is not limited to this.
  • the number and the shape of the arm portions are the inspection target in the region excluded from the inspection target region in the image of the wafer W held by the wafer holder in the first holding state and the image of the wafer W held in the wafer holder in the second holding state.
  • Two groups of arm portions configured so as not to overlap with a region excluded from the region, and the wafer W can be stably vacuum-sucked by the arm portions included in each group of arm portions. That's fine.
  • two types of holding states are not necessarily realized by two sets of arm portions, and even if three or more sets of arm portions are provided so as to realize three or more types of holding states. Good.
  • three or more sets of arm portions are arranged so that the region excluded from the inspection target region in the image of the wafer W held on the wafer holder does not overlap in all of the plurality of holding states. It only has to be configured. Note that when there are three or more holding states, portions excluded from the inspection target region can be overlapped as long as they do not overlap in all of the plurality of holding states. In the diffraction inspection, since the diffraction image is affected if the wafer W is distorted while being held, each arm portion needs to have flatness accuracy for holding the wafer W without being distorted. is there.
  • the first to eighth arm driving units 13a to 13h individually swing and displace the first to eighth arm units 12a to 12h to the suction position and the retracted position, respectively.
  • the present invention is not limited to this, and can be moved (displaced) by any method as long as it is retracted so as not to block light used for inspection. For example, you may make it slide to an adsorption
  • grooves (not shown) for vacuum suction are formed in the portions of the arm portions 12a to 12h that are in contact with the wafer W, but the present teaching is limited to this. It is not a thing.
  • the wafer W may be vacuum-sucked by a so-called pin chuck method (see the third embodiment described later), and the wafer W may be held by suction using a so-called electrostatic chuck. You may make it perform.
  • the inspection apparatus of the second embodiment has the same configuration as that of the inspection apparatus 1 of the first embodiment except for the wafer holder and the holding position changing unit, and the same reference numerals as those of the first embodiment are assigned to the respective parts. The detailed explanation is omitted.
  • the wafer holder 110 according to the second embodiment includes an annular frame portion 111 and three arm portions 112a to 112c that hold the wafer W by suction.
  • the frame portion 111 and the arm portions 112a to 112c are integrally formed.
  • the frame part 111 is formed in an annular shape having a diameter larger than that of the wafer W, and is configured to be tiltable together with a rotation driving part 131 described later in detail by a tilt mechanism 139 (see FIG. 10).
  • Each of the three arm portions 112a to 112c is formed in a substantially sector shape that is rotationally symmetric about the rotational symmetry axis AX1 of the frame portion 111, and is equally spaced along the inner peripheral portion of the frame portion 111 (at intervals of 120 degrees). Arranged. That is, the three arm portions 112 a to 112 c are disposed so as to extend toward the inner diameter side of the frame portion 111, and suck and hold the wafer W in a region surrounded by the frame portion 111. In addition, a region surrounded by the tip portions of the three arm portions 112a to 112c in the vicinity of the rotational symmetry axis AX1 of the frame portion 111 is referred to as an opening region H1.
  • the three arm portions 112a to 112c are referred to as a first arm portion 112a, a second arm portion 112b, and a third arm portion 112c, respectively, in the clockwise order from the right side of FIG. To do.
  • an inner suction portion 113a for sucking the wafer W On the surface of the first arm portion 112a, an inner suction portion 113a for sucking the wafer W, an intermediate suction portion 114a, and an outer suction portion 115a are formed in order from the front end side of the first arm portion 112a.
  • the inner suction portion 113a is provided near the distal end portion of the first arm portion 112a, that is, near the rotational symmetry axis AX1 of the frame portion 111.
  • the inner support part 116a is formed so as to extend in an elliptical shape, and is arranged so as to extend along the circumferential direction of the frame part 111.
  • the outer support portion 116b is formed so as to extend around the inner support portion 116a in an elliptical shape, and is disposed so as to extend along the circumferential direction of the frame portion 111.
  • the suction groove 117 is formed so as to extend in an elliptical shape between the inner support portion 116a and the outer support portion 116b.
  • the inner support portion 116a and the outer support portion 116b have the same height.
  • the decompression space surrounded by the support portions 116a and 116b and the wafer W located on both sides of the suction groove 117 is formed in the suction groove 117.
  • the wafer W is formed and sucked from the decompression space to reduce the pressure in the decompression space, whereby the wafer W is sucked and held by the inner suction portion 113a.
  • the inner side support part 116a and the outer side support part 116b are each formed in an ellipse shape, the decompression space formed between the inner side support part 116a and the outer side support part 116b is closed.
  • a suction hole 118 for sucking gas from the decompression space is formed on the bottom surface of the suction groove 117.
  • the suction hole 118 is formed so as to extend downward from the bottom surface of the suction groove 117, and the lower end portion of the suction hole 118 is connected to an internal passage 119 formed in the wafer holder 110 (first arm portion 112a) ( See FIG.
  • the internal passage 119 is formed so as to extend from each of the arm portions 112a to 112c to the outer peripheral portion of the frame portion 111 so as to open. It is connected to a vacuum source (not shown) (for example, a common decompression line of a production line) through the formed groove 133 and vacuum passage 134.
  • the intermediate suction portion 114a is provided in the middle portion of the first arm portion 112a, that is, in the middle of the rotational symmetry axis AX1 and the frame portion 111. Similar to the suction portion 113a, the inner support portion and the outer support portion, and suction grooves and the like are provided.
  • the outer suction portion 115a is provided near the proximal end portion of the first arm portion 112a, that is, closer to the inner peripheral portion of the frame portion 111, and detailed illustration is omitted. It has an outer support portion, a suction groove and the like.
  • an inner suction portion 113b for sucking the wafer W, an intermediate suction portion 114b, and an outer suction portion 115b are formed in this order from the front end side of the second arm portion 112b.
  • the inner suction portion 113b, the intermediate suction portion 114b, and the outer suction portion 115b of the second arm portion 112b have the same configuration as the inner suction portion 113a, the intermediate suction portion 114a, and the outer suction portion 115a of the first arm portion 112a. Detailed description will be omitted.
  • an inner suction portion 113c for sucking the wafer W is formed in order from the front end side of the third arm portion 112c.
  • the inner suction portion 113c, the intermediate suction portion 114c, and the outer suction portion 115c of the third arm portion 112c have the same configuration as the inner suction portion 113a, the intermediate suction portion 114a, and the outer suction portion 115a of the first arm portion 112a. Detailed description will be omitted.
  • the inner suction portions 113a to 113c, the intermediate suction portions 114a to 114c, and the outer suction portions 115a to 115c are formed concentrically around the rotational symmetry axis AX1 of the frame portion 111, respectively.
  • the width of the suction groove formed in each suction portion is set to a small width such that local distortion of the wafer W due to vacuum suction does not affect the inspection image.
  • each suction unit is configured so that local distortion of the wafer W due to vacuum suction does not affect the inspection image.
  • the opening angle of the first to third arm portions 112a to 112c formed in a substantially fan shape is It is preferably less than 60 degrees (circumference 360 degrees divided by 6).
  • the circumferential widths of the first to third arm portions 112a to 112c are smaller than the gap portions between the arm portions 112a to 112c, respectively, so that the holding position changing portion 120 (see FIG. 10) is used.
  • the wafer holder 110 can be rotated about the rotational symmetry axis AX1 of the frame portion 111 (for example, rotated by 60 degrees) at a position that does not overlap with the portions held by the arm portions 112a to 112c on the wafer W.
  • the first to third arm portions 112a to 112c need to have a size (opening angle ⁇ ) that can hold the wafer W without causing “deflection” due to its own weight.
  • the holding position changing unit 120 includes a temporary holding unit 121 that can hold the wafer W on the inner diameter side of the frame unit 111, a temporary holding unit driving unit 125 that displaces the temporary holding unit 121, and the wafer holder 110. And a rotation driving unit 131 that rotates the frame unit 111 about the rotational symmetry axis AX1.
  • the temporary holding unit 121 includes a stage 122 that holds the wafer W by suction, a support shaft 123 that supports the stage 122, and a lift base 124 that supports the support shaft 123.
  • the vertical and horizontal directions in a plane parallel to the paper surface are defined as the Z axis and the Y axis, respectively, and the direction perpendicular to the paper surface is defined as the X axis.
  • the stage 122 is formed in a disc shape that can pass through the opening H ⁇ b> 1 of the wafer holder 110, and has a support portion, a suction groove, and the like so as to suck the wafer W, like the suction portion of the wafer holder 110.
  • the support shaft 123 is formed in a vertically extending rod shape that can be inserted into the opening H ⁇ b> 1 of the wafer holder 110.
  • the elevating base 124 is formed in a plate shape extending substantially horizontally, and a nut 128b of a ball screw portion 128a provided in the temporary holding portion driving portion 125 (a linear motion guide and a ball screw portion (not shown) provided in the elevating portion 126). 128a and can be moved in the Z-axis direction by rotation of the ball screw 128a).
  • the temporary holding unit 121 is connected to the temporary holding unit driving unit 125.
  • the temporary holding unit drive unit 125 includes an elevating unit 126 that moves the temporary holding unit 121 up and down (up and down), and a horizontal moving unit 129 that moves the temporary holding unit 121 together with the elevating unit 126 (moves in the Y-axis direction). Configured.
  • the elevating part 126 has an elevating motor 127, a ball screw part 128 a that receives the rotational force of the elevating motor 127 and moving the elevating base 124 up and down, and a nut 128 b, and a stage together with the elevating base 124 and the support shaft 123.
  • 122 is configured to be movable up and down (up and down).
  • the horizontal moving unit 129 includes a horizontal moving motor, a ball screw, and the like, and is configured to be able to slide the elevating unit 126 and the temporary holding unit 121 in a substantially horizontal direction.
  • the horizontal moving unit 129 includes a standby position (see a solid line in FIG. 10) where the temporary holding unit 121 lowered to the lower side of the wafer holder 110 by the elevating unit 126 is positioned on the outer diameter side of the frame unit 111 of the wafer holder 110. It can be slid in a substantially horizontal direction between a position directly below the opening H1 of the wafer holder 110 (see a one-dot chain line in FIG. 10).
  • the elevating unit 126 inserts the temporary holding unit 121 slid to the position just below by the horizontal moving unit 129 through the opening H1 of the wafer holder 110, and separates the wafer W upward from the arm units 112a to 112c. Can be raised to a temporary holding position (see the two-dot chain line in FIG. 10).
  • the rotation driving unit 131 includes a rotation support unit 132 that is tiltably attached to the tilt mechanism 139 and rotatably supports the wafer holder 110, and a direct drive motor 136 that is attached to the rotation support unit 132 and rotates the wafer holder 110. It is configured.
  • the rotation support portion 132 is formed in an annular shape surrounding the periphery of the wafer holder 110, and rotatably supports the outer peripheral portion of the frame portion 111 of the wafer holder 110 via a bearing 135 attached to the inner peripheral portion of the rotation support portion 132. To do.
  • the direct drive motor 136 is formed in an annular shape that matches the shape of the rotation support portion 132 and the frame portion 111, and is attached to the lower end portion of the rotation support portion 132 to rotate the frame portion 111.
  • the frame portion 111 of the wafer holder 110 can rotate about the rotational symmetry axis AX1 of the frame portion 111 together with the arm portions 112a to 112c.
  • a groove portion 133 is formed on the inner peripheral portion of the rotation support portion 132 so as to communicate with the internal passage 119 of the frame portion 111, and a vacuum passage 134 is formed inside the rotation support portion 132 so as to be connected to the groove portion 133. Yes.
  • the vacuum passage 134 is formed so as to open from the groove portion 133 of the rotation support portion 132 to the outer peripheral portion, and a pipe or the like connected to a vacuum source (not shown) is connected to the opening portion of the vacuum passage 134.
  • the bearing 135 is configured to have a seal member (not shown), is attached to the upper and lower ends of the inner peripheral portion of the rotation support portion 132, and is externally provided in a space surrounded by the frame portion 111 and the groove portion 133. Gas is prevented from flowing in.
  • a wafer W inspection / evaluation method using the inspection apparatus of the second embodiment will be described.
  • the wafer W to be inspected is transferred above the wafer holder 110 by a transfer device (not shown) so that the surface (the surface on which the inspection target is provided) faces upward.
  • the wafer W is aligned on the wafer holder 110 by the alignment mechanism (not shown) on the basis of a reference mark (notch, orientation flat, etc.) provided on the outer edge portion by an alignment mechanism (not shown) during the transfer.
  • the temporary holding unit 121 is held substantially horizontally by the operation of the holding position changing unit 120 (temporary holding unit driving unit 125).
  • the wafer W is inserted into the opening H1 of the wafer holder 110 and raised to the above-described temporary holding position, and the wafer W is once mounted on the stage 122 of the temporary holding unit 121 by a transfer device (not shown). After mounting, the wafer W is sucked and held on the stage 122.
  • the elevating unit 126 of the temporary holding unit driving unit 125 lowers the wafer W sucked and held on the stage 122 of the temporary holding unit 121 to the wafer holder 110 together with the temporary holding unit 121, and the wafer by the temporary holding unit 121.
  • the back surface of the wafer W is suctioned by the wafer holder 110. Note that it is not necessary to cancel the adsorption of the back surface of the wafer W by the temporary holding unit 121 and the adsorption of the wafer W by the wafer holder 110 at the same time, but the wafer W is lowered to just before contacting the wafer holder 110.
  • the wafer W may be gently lowered and the back surface of the wafer W may be suctioned by the wafer holder 110 after the wafer holder 110 and the wafer W come into contact with each other.
  • the temporary holding unit 121 is removed from the opening H1 of the wafer holder 110 by the elevating unit 126 of the temporary holding unit driving unit 125 and is lowered to the above-described directly lower position, and the temporary holding unit 121 lowered to the immediately below position is moved horizontally. 129 is slid to the standby position described above.
  • the wafer W is held on the wafer holder 110, and the wafer holder 110 can be tilted together with the rotation driving unit 131 by the tilt mechanism 139.
  • the wafer holder 110 rotates the first to third arm portions 112a to 112c as shown in FIG. 8A and FIG. In the first holding state, the wafer W is sucked and held.
  • each part of the inspection apparatus (wafer holder 110, holding position changing part 120, tilt mechanism 139, first and second illumination units 21, 41, first and second imaging parts 35, 55, etc.) It is driven in response to a command from the control unit 60.
  • illumination light including a wavelength (for example, a wavelength of 1100 nm) set by the dimming unit is emitted from the second illumination unit 41 to the second illumination side concave mirror 45,
  • the illumination light reflected by the second illumination side concave mirror 45 is converted into parallel light and is irradiated on the entire back surface of the wafer W held by the wafer holder 110 in the first holding state.
  • setting (tilt) is performed so that diffracted light generated in the repetitive pattern A of the wafer W can be received by the second detection unit 50.
  • the repeating direction of the pattern on the wafer W is parallel to the incident surface of the illumination light, and the posture of the tilt angle is such that the diffracted light can be received by the second detection unit.
  • the diffracted light that is generated by the repetitive pattern A of the wafer W and is emitted (reflected) from the back surface side is collected by the second light receiving side concave mirror 51 and reaches the imaging surface of the second imaging unit 55 in the first holding state.
  • An image of the wafer W held by the wafer holder 110 (image by diffracted light) is formed.
  • the image sensor of the second imaging unit 55 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is transmitted to the image processing unit via the control unit 60. To 61.
  • the wafer holder 110 When an image of the wafer W held by the wafer holder 110 in the first holding state is picked up, the wafer holder 110 is moved by the operation of the holding position changing unit 120 as shown in FIGS. 8B and 9B.
  • the wafer W is sucked and held by the first to third arm portions 112a to 112c in a state where the holding state is rotationally displaced by 60 degrees around the rotational symmetry axis AX1 (hereinafter referred to as a second holding state for convenience).
  • the holding position of the wafer holder 110 with respect to the wafer W can be changed (to a position rotated by 60 degrees around the rotational symmetry axis AX1 of the frame portion 111).
  • the tilt mechanism 139 is operated to tilt the wafer holder 110 together with the rotation drive unit 131 so as to be substantially horizontal.
  • the temporary holding unit 121 located at the standby position is slid to the directly below position by the horizontal moving unit 129, and the temporary holding unit 121 slid to the directly below position is moved by the lifting unit 126.
  • the wafer W is raised until it contacts the back surface. At this time, suction of the back surface of the wafer W by the wafer holder 110 is released, and at the same time, suction of the back surface of the wafer W by the temporary holding unit 121 is performed.
  • the back surface of the wafer W may be suctioned by the temporary holding unit 121.
  • the temporary holding unit 121 holding the wafer W is lifted to the temporary holding position by the elevating unit 126, and the temporary holding unit 121 holds the wafer W without the arms 112a to 112c holding the wafer W.
  • the frame unit 111 is rotated together with the arm units 112a to 112c by the direct drive motor 136 of the rotation driving unit 131.
  • the wafer holder 110 is rotated by 60 degrees about the rotational symmetry axis AX1 of the frame 111.
  • the rotation direction may be clockwise or counterclockwise, and the rotation amount may be 180 degrees or 300 degrees.
  • the lifting / lowering unit 126 holds the wafer W sucked and held on the stage 122 of the temporary holding unit 121.
  • the wafer holder 110 is lowered onto the wafer holder 110 together with the holding unit 121 to release the adsorption of the back surface of the wafer W by the temporary holding unit 121, and at the same time, the wafer holder 110 adsorbs the back surface of the wafer W.
  • the temporary holding unit 121 is lowered to the position immediately below by the elevating unit 126, and the temporary holding unit 121 lowered to the position just below is waited by the horizontal moving unit 129. Slide to position.
  • tilt angle is the same as when the wafer W is held in the first holding state by the operation of the tilt mechanism 139 (the same as the case where the second detection unit 50 receives diffracted light in the first holding state).
  • the wafer holder 110 is tilted so as to return to. In this posture, the pattern repeat direction on the wafer W is parallel to the illumination light incident surface.
  • illumination light having the same wavelength as that when the wafer W is held in the first holding state is emitted from the second illumination unit 41 to the second illumination side concave mirror 45, and the illumination light reflected by the second illumination side concave mirror 45 is emitted.
  • the parallel light is irradiated onto the entire back surface of the wafer W held by the wafer holder 110 in the second holding state.
  • the second detection unit 50 can receive diffracted light under the same conditions as when the wafer W is held in the first holding state, and an image of the wafer W can be formed.
  • the diffracted light generated by the repeated pattern A of the wafer W and emitted from the back surface side is condensed by the second light receiving side concave mirror 51 and reaches the image pickup surface of the second image pickup unit 55, and the wafer holder 110 in the second holding state.
  • An image of the wafer W held on (image by diffracted light) is formed.
  • the image sensor of the second imaging unit 55 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is transmitted to the image processing unit via the control unit 60. To 61.
  • the image processing unit 61 is based on the image signals input from the second imaging unit 55 in the first holding state and the second holding state, respectively. Then, an image (digital image) of the wafer W is generated. At this time, in the image of the wafer W held by the wafer holder 110 in the first holding state, the portions adsorbed and held by the first to third arm portions 112a to 112c and the vicinity thereof are shadows of these arms, so that the inspection is performed. Exclude from the target area.
  • the portions adsorbed and held by the first to third arm portions 112a to 112c and the vicinity thereof are shadows of these arms, so Exclude from area.
  • the image signal of the wafer W (digital image) is generated by combining the image signal of the non-holding portion excluding the portion (and the vicinity thereof) held by the arm portions 112a to 112c in the wafer W held on the wafer W.
  • the image of the wafer W held on the wafer holder 110 in the state is basically not relatively displaced, but if necessary, an image of the non-holding portion of the wafer W held on the wafer holder 110 in the first holding state. Alignment may be performed on the basis of a pattern existing in an overlapping area between the image of the non-holding portion of the wafer W held by the wafer holder 110 in the second holding state. In the synthesis, the image corresponding to the holding portion (and its vicinity) in one image adopts the image of the other non-holding portion, and the average value of the two images is used in the overlapping region of the non-holding portion. .
  • a weighted average value of two images may be further employed. For example, if the weight of one image is close to the holding portion, the weight of the image is decreased (the other weight is increased), and the weight is increased at a distance (the other is decreased). It is possible to obtain an image of the wafer W without an unnatural signal change based on a subtle brightness difference between two images caused by imaging noise or the like.
  • the image processing unit 61 When the image processing unit 61 generates the composite image of the wafer W, the non-defective product (in the back surface diffraction inspection) stored in the image data and database (not shown) of the generated wafer W, as in the first embodiment.
  • the wafer image data is compared, and the wafer W is inspected for abnormalities (defects) or the pattern is evaluated. Then, the result of the back surface diffraction inspection by the image processing unit 61 and the image of the wafer W at that time are output and displayed on the display unit 62 and also output to an external computer or the like by the output unit 63.
  • inspection and evaluation are performed under a plurality of conditions with different depths at which the illumination light reaches the wafer W, and the inspection results at each illumination wavelength are combined.
  • the type of abnormality (defect) in the wafer W can be determined, as in the first embodiment.
  • the holding position changing unit 120 that changes the holding position of the wafer holder 110 with respect to the wafer W is provided, the same effect as in the case of the first embodiment can be obtained.
  • the rotation driving part 131 is used for the frame part 111 and the first to third arm parts 112a. Since the holding position of the wafer holder 110 with respect to the wafer W is changed by rotating the .about.112c integrally, the holding position without adsorbing the front surface side (surface opposite to the attracted surface) of the wafer W. Can be changed. Thereby, the holding position can be changed without damaging the surface side of the wafer W.
  • the repetition direction of the pattern A with respect to the second illumination unit 40 and the second detection unit 50 can be kept constant, Regardless of the holding position of the wafer holder 110, it is possible to detect diffracted light under the same conditions and perform a highly accurate back surface diffraction inspection (inspection or evaluation of the wafer W).
  • the rotation driving unit 131 integrates the frame unit 111 and the first to third arm units 112a to 112c. Therefore, the temporary holding unit 121 can easily hold the wafer W.
  • the three arm portions 112a to 112c are provided.
  • the number of the arm portions 112a to 112c is not limited to this, and may be four, for example, and can stably hold the wafer W. It is only necessary to provide a plurality.
  • the opening angle (center angle) of the substantially fan-shaped arm portions is less than (180 / n) degrees.
  • each arm portion is smaller than the gap between the arm portions, so that the region excluded from the inspection target region in the image of the wafer W held by the wafer holder in the first holding state, and the second holding state
  • the frame portion and each arm portion can be rotated so that the region excluded from the inspection target region does not overlap in the image of the wafer W held by the wafer holder. Therefore, the back surface diffraction inspection of the wafer W can be performed in a short time only by performing a minimum of two imaging operations.
  • the arm opening angle In the case of a thin wafer (thickness: 100 ⁇ m), it is very easy to bend, so it is necessary to set the arm opening angle to (180 / n) degrees or more. What is necessary is just to image.
  • the three arm portions 112a to 112c are formed in a substantially fan shape.
  • the present invention is not limited to this.
  • the arm portions 112a to 112c may be formed in a rectangular shape to stabilize the wafer W. Any shape that can be held is acceptable.
  • the transmission diffraction inspection of the wafer W held by the wafer holder 110 of the second embodiment is performed in the same manner as the transmission diffraction inspection described in the first embodiment.
  • the image processing unit 61 does not include the portions (and the vicinity thereof) held by the arms 112a to 112c in the wafer W held by the wafer holder 110 in the first holding state.
  • the image signal of the holding portion is synthesized with the image signal of the non-holding portion excluding the portion (and the vicinity thereof) held by the arms 112a to 112c in the wafer W held by the wafer holder 110 in the second holding state.
  • an image (digital image) of the wafer W is generated and the presence or absence of an abnormality (defect) in the wafer W is inspected, but the present invention is not limited to this.
  • the wafer holder in the second holding state is inspected for the presence (abnormality) of the non-holding portion in the wafer W.
  • the presence or absence of an abnormality (defect) in the non-holding portion in the wafer W is inspected, and the two inspection results are combined (specifically, determined as abnormal) Or, a logical sum (OR) of the inspection results may be taken).
  • the elevating unit 126 and the horizontal moving unit 129 of the temporary holding unit driving unit 125 are configured using a motor and a ball screw, but the present teaching is not limited to this. As occasion demands, another configuration can be adopted as appropriate. For example, you may comprise using a linear motor.
  • the temporary holding unit 121 (and the elevating unit 126) is slid between the standby position and the directly below position using the horizontal moving unit 129. It is not limited, and a movement method other than slide movement can be adopted.
  • the temporary holding unit 121 (and the lifting unit 126) may be rotationally moved between the standby position and the directly below position using a turntable.
  • the wafer holder 110 is rotated using the direct drive motor 136.
  • the present teaching is not limited to this, and an arbitrary rotation mechanism may be adopted as necessary. it can.
  • the wafer holder 110 may be rotated using a servo motor.
  • the suction and holding of the wafer W is performed using vacuum suction.
  • electrostatic force is used by a so-called electrostatic chuck.
  • the wafer W may be sucked and held.
  • the inspection apparatus of the third embodiment has the same configuration as that of the inspection apparatus of the second embodiment except for the wafer holder, and the same reference numerals as those of the second embodiment are given to the respective parts, and detailed description thereof is omitted.
  • the wafer holder 160 according to the third embodiment performs vacuum suction of the wafer W by a so-called pin chuck method, and holds the annular frame 161 and the wafer W by suction similarly to the wafer holder 110 according to the second embodiment. It has three arm portions 162a to 162c.
  • the frame portion 161 is formed in an annular shape having a diameter larger than that of the wafer W, and is configured to be tiltable together with the rotation drive portion 131 by the tilt mechanism 139, similarly to the wafer holder 110 of the second embodiment.
  • the three arm portions 162a to 162c are each formed in a substantially fan shape that is rotationally symmetrical about the rotational symmetry axis AX2 of the frame portion 161, and are equally spaced along the inner peripheral portion of the frame portion 161 (at intervals of 120 degrees). Arranged. That is, the three arm portions 162a to 162c are arranged so as to extend toward the inner diameter side of the frame portion 161 so as to suck and hold the wafer W in a region surrounded by the frame portion 161.
  • an area surrounded by the tip ends of the three arm portions 162a to 162c in the vicinity of the rotational symmetry axis AX2 of the frame portion 161 is referred to as an opening portion H2, and like the wafer holder 110 of the second embodiment, a temporary holding portion. 121 is configured to be insertable.
  • the three arm portions 162a to 162c are referred to as a first arm portion 162a, a second arm portion 162b, and a third arm portion 162c, respectively, in the clockwise order from the right side of FIG. To do.
  • a suction part 163a for sucking and holding the wafer W is formed on the surface of the first arm part 162a.
  • the suction part 163a is formed over substantially the entire surface of the first arm part 162a, and as shown in FIG. 11B, a plurality of protrusions 166 that support the wafer W when sucking the wafer W, and a plurality of protrusions 166
  • An outer wall 167 that supports the wafer W and is formed so as to surround the protrusion 166 is configured.
  • Each protrusion 166 is formed in a columnar shape or a hemispherical shape. However, the present teaching is not limited to such a configuration, and the shape of the protrusion 166 can be any shape as necessary.
  • the heights of the protrusions 166 and the outer wall part 167 are designed to be the same, and by aligning these heights with high precision, the wafer W supported by the protrusions 166 and the outer wall part 167 of the wafer W is designed. Flatness accuracy can be ensured. Note that the flatness of the wafer W increases as the arrangement interval of the protrusions 166 decreases. Further, the suction holding force becomes larger and more stable as the suction portion 163a is larger. Therefore, when the rotational symmetry axis AX2 and the center of the wafer W are held in alignment, the vicinity of the peripheral edge of the wafer W and the outer wall 167 come into contact with each other.
  • a decompression space surrounded by the outer wall 167, each protrusion 166, and the wafer W is formed in a region inside the outer wall 167.
  • the wafer W is attracted and held by the attracting portion 163a.
  • a suction hole 168 for sucking gas from the reduced pressure space is formed as in the wafer holder 110 of the second embodiment.
  • the suction portions 163b and 163c for sucking and holding the wafer W are also formed on the surfaces of the second arm portion 162b and the third arm portion 162c, respectively.
  • the suction portions 163b and 163c of the second arm portion 162b and the third arm portion 162c have the same configuration as the suction portion 163a of the first arm portion 162a, and detailed description thereof is omitted.
  • the same inspection as that of the second embodiment that is, the front surface diffraction inspection and the back surface diffraction inspection of the wafer W
  • the same effect as in the second embodiment can be obtained.
  • the number of arm portions may be four as long as a plurality of wafers W can be stably held.
  • the opening angle (center angle) of the substantially fan-shaped arm portions is less than (180 / n) degrees.
  • the arm portion may be formed in a rectangular shape as long as it can hold the wafer W stably.
  • the wafer holder 160 may be rotated using a servo motor as in the case of the second embodiment.
  • the inspection apparatus 201 of the fourth embodiment includes a wafer holder 10 similar to that of the first embodiment, and the wafer holder 10 is given the same reference numerals as in the case of the first embodiment and detailed description thereof is omitted.
  • the tilt mechanism 219 provided in the wafer holder 10 causes the wafer W held by the wafer holder 10 to be centered on an axis parallel to the surface of the wafer W (an axis extending in the X-axis direction). Can be rotated (that is, rotated about an axis perpendicular to the incident surface of the illumination light).
  • the vertical direction of the paper surface is the Z axis
  • the horizontal direction of the paper surface is the Y axis
  • the direction perpendicular to the paper surface is the X axis.
  • the inspection apparatus 201 further includes an illuminating unit 220 that irradiates illumination light (inspection light) as parallel light on the front surface or back surface of the wafer W held by the wafer holder 10, and the front surface of the wafer W when irradiated with the illumination light.
  • the detection unit 230 that detects light from the back surface, the control unit 260 that controls the apparatus, the image processing unit 261 that performs image processing, the display unit 262 that performs image display, and the processing results of the image processing unit 261 are externally transmitted.
  • An output unit 263 for outputting to a computer or the like is provided.
  • the illumination unit 220 includes an illumination unit 221 that emits illumination light, and an illumination-side concave mirror 225 that reflects the illumination light emitted from the illumination unit 221 toward the front or back surface of the wafer W.
  • the illumination unit 221 has the same configuration as the first illumination unit 21 in the first embodiment, and includes a light source unit 222, a light control unit 223, and a light guide fiber 224.
  • the light from the light source unit 222 passes through the light control unit 223, and illumination light having a predetermined wavelength and having a predetermined intensity is emitted from the light guide fiber 224 to the illumination side concave mirror 225 to become diverging light.
  • the illumination light (diverging light) emitted from the light guide fiber 224 to the illumination side concave mirror 225 is parallel to the illumination side concave mirror 225 because the exit portion of the light guide fiber 224 is disposed on the focal plane of the illumination side concave mirror 225.
  • (Telecentric) light is applied to the entire front or back surface of the wafer W held by the wafer holder 10.
  • the incident angle and the emission angle of the illumination light with respect to the wafer W can be adjusted by rotating the wafer holder 10 to change the mounting angle of the wafer W.
  • the light emitted from the wafer W (diffracted light, specularly reflected light, etc.) is detected by the detection unit 230.
  • the detection unit 230 is mainly composed of a light receiving side concave mirror 231 and an image pickup unit 235 arranged to face the wafer holder 10, and the emitted light condensed by the light receiving side concave mirror 231 is on the image pickup surface of the image pickup unit 235.
  • the image of the wafer W is formed.
  • the imaging unit 235 includes an objective lens, an image sensor, and the like (not shown).
  • the imaging unit 235 generates an image signal (detection signal) by photoelectrically converting an image of the wafer W formed on the imaging surface of the image sensor, and the generated image signal. Is output to the image processing unit 261 via the control unit 260.
  • the control unit 260 controls the operations of the wafer holder 10, the tilt mechanism 219, the illumination unit 221, the imaging unit 235, and the like.
  • the image processing unit 261 generates an image (digital image) of the wafer W based on the image signal input from the imaging unit 235.
  • a database (not shown) electrically connected to the image processing unit 261 stores image data of non-defective wafers in advance. When the image processing unit 261 generates an image of the wafer W, the generated wafer W is generated. The image data of the non-defective wafer stored in the database is compared, and the presence or absence of an abnormality (defect) in the wafer W is inspected.
  • the image processing unit 261 and the database do not necessarily have to be electrically connected as long as they are communicably connected by wire (including an optical line) or wirelessly. Then, the inspection result by the image processing unit 261 and the image of the wafer W at that time are output and displayed on the display unit 262.
  • a wafer W inspection / evaluation method using the inspection apparatus 201 configured as described above will be described.
  • a wafer W to be inspected is previously transferred onto the wafer holder 10 by a transfer device (not shown) so that the surface (the surface on which the inspection target is provided) faces upward. Further, the wafer W is aligned in the middle of the transfer in the same manner as in the first embodiment, and the wafer W can be placed at a desired position on the wafer holder 10 in a desired direction. At this time, the wafer holder 10 sucks and holds the wafer W in the first holding state as in the case of the first embodiment.
  • each part of the inspection apparatus (wafer holder 10, first to eighth arm driving units 13a to 13h, tilt mechanism 219, illumination unit 221, imaging unit 235, etc.) receives a command from the control unit 260. Driven.
  • the tilt mechanism 219 is operated so that the back surface of the wafer W faces upward.
  • the wafer holder 10 is rotated.
  • illumination light having a predetermined wavelength for example, 1100 nm wavelength
  • the illumination-side concave mirror 225 based on a command from the control unit 260, and the illumination light reflected by the illumination-side concave mirror 225 is parallel light.
  • the entire back surface of the wafer W held by the wafer holder 10 in the first holding state is irradiated.
  • the wafer W penetrates the wafer W by adjusting the tilt angle (tilt angle) of the wafer W held by the wafer holder 10 in the same manner as in the surface diffraction inspection. Then, the diffracted light diffracted by the pattern and emitted from the back surface side is received by the detection unit 230 and an image can be formed.
  • the diffracted light generated from the repetitive pattern A of the wafer W and emitted from the back surface side is condensed by the light receiving side concave mirror 231, reaches the imaging surface of the imaging unit 235, and is held by the wafer holder 10 in the first holding state.
  • An image of the wafer W (image by diffracted light) is formed.
  • the image sensor of the imaging unit 235 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is sent to the image processing unit 261 via the control unit 260. Output.
  • the wafer holder 10 When an image of the wafer W held by the wafer holder 10 in the first holding state is picked up, the wafer holder 10 sucks and holds the wafer W in the second holding state by the operation of the first to eighth arm driving units 13a to 13h. Switching from the first holding state to the second holding state is performed in the same manner as in the first embodiment with the back surface of the wafer W facing upward.
  • the wafer W can be prevented from dropping by releasing the suction and holding of the arm used in the first holding state after confirming the suction and holding by a vacuum sensor (not shown) when the second holding state is reached. Note that switching from the first holding state to the second holding state may be performed in a state where the wafer W is once reversed and the surface thereof is directed upward.
  • illumination light having the same wavelength as that when the wafer W is held in the first holding state is emitted from the illumination unit 221 to the illumination side concave mirror 225, and the illumination light reflected by the illumination side concave mirror 225 becomes parallel light.
  • the entire back surface of the wafer W held by the wafer holder 10 in the holding state is irradiated.
  • the tilt angle of the wafer W held by the wafer holder 10 does not change only by changing the holding position of the wafer holder 10 with respect to the wafer W (the arm part displaced to the suction position), so that in the first holding state
  • the diffracted light under the same conditions as when the wafer W is held can be received by the detection unit 230 to form an image of the wafer W.
  • the diffracted light emitted (reflected) from the back surface side generated by the repetitive pattern A of the wafer W is collected by the light receiving side concave mirror 231 and reaches the image pickup surface of the image pickup unit 235, and reaches the wafer holder 10 in the second holding state.
  • An image of the held wafer W (image by diffracted light) is formed.
  • the image sensor of the imaging unit 235 photoelectrically converts the image of the wafer W formed on the imaging surface to generate an image signal, and the generated image signal is sent to the image processing unit 261 via the control unit 260. Output.
  • the image processing unit 261 performs the first processing based on the image signals input from the imaging unit 235 in the first holding state and the second holding state, respectively.
  • a composite image (digital image) of the wafer W is generated, and the presence or absence of an abnormality (defect) in the wafer W is checked or the pattern is evaluated. Then, the result of the back surface diffraction inspection by the image processing unit 261 and the image of the wafer W at that time are output and displayed on the display unit 262 and output to an external computer or the like by the output unit 263.
  • inspection and evaluation are performed under a plurality of conditions with different depths at which the illumination light reaches the wafer W, and the inspection results at each illumination wavelength are combined.
  • the type of abnormality (defect) in the wafer W can be determined as in the first embodiment.
  • the same effect as in the first embodiment can be obtained. Moreover, since the same illumination part 220 and the detection part 230 can be used in a surface diffraction test
  • the non-holding portion of the wafer W is based on the image signal of the non-holding portion of the wafer W held by the wafer holder 10 in the first holding state. And checking whether there is an abnormality (defect) in the non-holding portion of the wafer W based on the image signal of the non-holding portion in the wafer W held by the wafer holder 10 in the second holding state. Inspection may be performed so that the two inspection results are combined.
  • the number and shape of the arm portions are excluded from the inspection target region in the image of the wafer W held by the wafer holder in the first holding state.
  • Two groups of arm portions configured so that the region and the region excluded from the inspection target region in the image of the wafer W held by the wafer holder held in the second holding state do not overlap each other. What is necessary is just to be able to stably vacuum-suck the wafer W by the arm part included in the part group.
  • two types of holding states are not necessarily realized by two sets of arm portions, and even if three or more sets of arm portions are provided so as to realize three or more types of holding states. Good.
  • three or more sets of arm portions are arranged so that the region excluded from the inspection target region in the image of the wafer W held on the wafer holder does not overlap in all of the plurality of holding states. It only has to be configured.
  • the arm drive unit may be configured to slide the arm unit to the suction position and the retracted position, and the light used for the inspection may be used. Any structure may be used as long as it is retracted so as not to block.
  • the wafer W may be vacuum-sucked by a so-called pin chuck method, and electrostatic force is used by a so-called electrostatic chuck. Then, the wafer W may be sucked and held.
  • the same wafer holder 10 as in the first embodiment is provided.
  • the present invention is not limited to this, and the same wafer holder 110 (and holding position changing unit 120) as in the second embodiment.
  • a wafer holder 160 (and holding position changing unit 120) similar to that of the third embodiment may be provided. Thereby, the effect similar to the case of 2nd Embodiment (or 3rd Embodiment) can be acquired.
  • the inspection object is the same as in the second embodiment.
  • the tilt mechanism 219 operates to rotate the wafer holder 110 so that the back surface of the wafer W faces upward. Further, switching from the first holding state to the second holding state is performed after the wafer holder 110 is rotated by the operation of the tilt mechanism 219 so that the surface of the wafer W faces upward and becomes substantially horizontal. This is performed in the same manner as in the case of the embodiment.
  • the wafer W in order to perform the back surface diffraction inspection of the wafer W using the illumination unit 220 and the imaging unit 230 provided above the wafer holder, the wafer W is held on the wafer holder so that the surface of the wafer W faces upward. Thereafter, the tilt angle is adjusted so that the imaging unit 230 receives the diffracted light with a predetermined pitch by rotating the wafer holder and the wafer so that the back surface of the wafer faces upward using the tilt mechanism.
  • This configuration has the advantage that the device configuration can be simplified and the size of the device can be reduced.
  • the present invention is not limited to this, and a mechanism for rotating the wafer holder and the wafer W so that the back surface of the wafer faces upward is referred to as a tilt mechanism. It may be provided separately.
  • the concave mirror is used for the illumination unit and the detection unit.
  • the present invention is not limited to this, and it can be replaced with a lens.
  • the light source is built in, but the present invention is not limited to this, and light generated outside may be captured by a fiber or the like.
  • the hole pattern is described as an example of the pattern A.
  • the inspection target is not limited to this, and the depth from the substrate surface to the direction orthogonal to the surface is described. Any pattern may be used. For example, not only a hole pattern but also a line and space pattern may be used.
  • the inspection of the TSV provided on the silicon wafer as the inspection target has been described.
  • the present invention is not limited to this.
  • the present invention is applicable to a liquid crystal substrate in which a liquid crystal circuit is provided on a glass substrate. Is possible.
  • the surface diffraction inspection is performed by one imaging without changing the holding state of the wafer W.
  • the surface diffraction inspection for example, when illumination light having a wavelength of 1100 nm is used, since the transmittance is high, the light reaches the arm of the wafer holder and is reflected, and the reflected light is reflected in the image and becomes inspection noise. There is a possibility that. Therefore, as in the case of the back surface diffraction inspection, the inspection is performed in the first holding state and the second holding state, and the portions where the arms and the like of both images are not reflected are synthesized and inspected as an image of the entire wafer W. .
  • light that is not used for inspection among the light reflected or diffracted by the wafer may be reflected in the inspection image.
  • light diffracted (including the 0th order) by the wafer W is reflected by an apparatus cover or the like and wraps around and is reflected in an image. Therefore, it is desirable to arrange a member that absorbs light on the inner surface of the apparatus.
  • the flowchart in FIG. 13 shows a TSV formation process in a three-dimensional stacked semiconductor device.
  • a resist is applied to the surface of a wafer (such as a bare wafer) (step S101).
  • a wafer is fixed to a rotating support base with a vacuum chuck or the like using a resist coating apparatus (not shown), and a liquid photoresist is dropped from the nozzle onto the surface of the wafer.
  • a thin resist film is formed by rotating at high speed.
  • a predetermined pattern (hole pattern) is projected and exposed on the surface of the wafer coated with the resist (step S102).
  • the resist on the wafer surface is irradiated with light of a predetermined wavelength (for example, energy rays such as ultraviolet rays) through a photomask on which a predetermined pattern is formed using an exposure apparatus, and the mask pattern is applied to the wafer. Transfer to the surface.
  • a predetermined wavelength for example, energy rays such as ultraviolet rays
  • step S103 development is performed (step S103).
  • a developing device (not shown) is used to dissolve the resist in the exposed area with a developer and leave a resist pattern in the unexposed area. As a result, a hole pattern is formed in the resist on the wafer surface.
  • step S104 the surface of the wafer on which the resist pattern (hole pattern) is formed is inspected.
  • a surface inspection device (not shown) is used, for example, the entire surface of the wafer is irradiated with illumination light, and an image of the wafer is captured by the diffracted light generated in the resist pattern.
  • the wafer image is inspected for abnormalities such as a resist pattern. In this inspection process, whether or not the resist pattern is good is determined. If the resist pattern is defective, it is determined whether or not rework is to be performed, that is, the resist is peeled off and restarted from the resist coating process.
  • step S105 When an abnormality (defect) that requires rework is detected, the resist is removed (step S105), and the processes from steps S101 to S103 are performed again.
  • the inspection result by the surface inspection apparatus is fed back to the resist coating apparatus, the exposure apparatus, and the developing apparatus.
  • etching is performed (step S106).
  • an etching apparatus (not shown) is used to etch the silicon portion of the underlying bare wafer using, for example, the remaining resist as a mask to form TSV formation holes. As a result, a TSV hole pattern is formed on the surface of the wafer W.
  • the wafer W on which the pattern A is formed by etching is inspected (step S107).
  • the inspection process after etching is performed using the inspection apparatus according to any one of the embodiments described above. If an abnormality is detected in this inspection process, the exposure conditions (deformation illumination conditions, focus offset conditions, etc.) of the exposure apparatus and the etching apparatus are selected according to the type and degree of abnormality including the determined abnormality depth. It is determined whether to adjust the parameters, whether to discard the wafer W, or whether a detailed analysis such as observing the cross section of the wafer W is necessary. If a serious and wide-range abnormality is found in the etched wafer W, it cannot be reworked, and the wafer W is discarded or sent for analysis such as cross-sectional observation (step S108).
  • an insulating film (or barrier metal) is formed on the side wall of the hole (step S109), and the hole portion where the insulating film is formed is filled with Cu (step S110). . Thereby, a three-dimensional mounting through electrode is formed on the wafer (bare wafer).
  • a hole having a high aspect ratio (depth / diameter) (for example, 10 to 20) must be formed, which is technically difficult. is important.
  • RIE Reactive Ion Etching
  • feedback operation is mainly performed in which the etching apparatus is monitored for abnormalities, and when abnormalities are detected, the etching apparatus is stopped and adjusted.
  • parameters for adjusting the etching apparatus for example, parameters for controlling the etching rate ratio between the vertical direction and the horizontal direction, parameters for controlling the depth of holes such as etching time, and uniformity within the wafer surface are controlled.
  • a parameter etc. can be considered.
  • the inspection results in the inspection process after etching it is also possible to feed forward the inspection results in the inspection process after etching to the subsequent processes.
  • the information is transmitted from the above-described inspection apparatus to a host computer (not shown) that manages the process online. It is used for the management such as not using the abnormal part (chip) in the inspection / measurement in the subsequent process, and the unnecessary electrical test is not performed when the device is finally completed. Be utilized. Also, if the area of the abnormal part is large from the inspection result in the inspection process after etching, adjust the parameters for insulating film formation and Cu filling accordingly to reduce the influence on the non-defective part, etc. Can do.
  • the inspection process after etching is performed using the inspection apparatus according to any one of the above-described embodiments, the change in the shape of the pattern A in the depth direction is detected. Since the inspection accuracy is improved, the manufacturing efficiency and performance uniformity of the semiconductor device can be improved.
  • the TSV is formed at the first stage before the element is formed on the wafer.
  • the present teaching is not limited to this, and the TSV is formed after the element is formed.
  • the TSV may be formed during the element formation.
  • the transparency to infrared rays is reduced, but it is not completely opaque, so wavelength selection and adjustment of the amount of illumination light are taken into account the change in transparency. Just do it.
  • the portion where the element is formed by ion implantation or the like is in a state where it does not transmit infrared rays at all, the hole shape inspection by the back surface diffraction inspection is possible.
  • inspection can be performed without being affected by the decrease in transparency caused by ion implantation if TSVs are formed on the bare wafer for inspection and QC purposes. It is.
  • the present invention can be applied to an inspection apparatus used in an inspection process after etching in the manufacture of a semiconductor device. Thereby, the inspection accuracy of the inspection apparatus can be improved, and the manufacturing efficiency of the semiconductor device can be improved.
  • Inspection device (first embodiment; evaluation device) 10 Wafer holder (holding member) 11 Frame part 12a 1st arm part 12b 2nd arm part 12c 3rd arm part 12d 4th arm part 12e 5th arm part 12f 6th arm part 12g 7th arm part 12h 8th arm part 13a 1st arm drive part 13b 2nd arm drive unit 13c 3rd arm drive unit 13d 4th arm drive unit 13e 5th arm drive unit 13f 6th arm drive unit 13g 7th arm drive unit 13h 8th arm drive unit 19 Tilt mechanism (adjustment unit) 20 1st illumination part 30 1st detection part 40 2nd illumination part 50 2nd detection part 60 Control part 61 Image processing part (evaluation part or test

Landscapes

  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)
  • Testing Or Measuring Of Semiconductors Or The Like (AREA)

Abstract

La présente invention concerne un appareil capable d'effectuer une évaluation ou une inspection avec une précision élevée. L'appareil est pourvu : d'un porte-tranche (10) retenant une tranche (W) ; d'une section d'éclairage émettant une lumière d'éclairage sur la tranche (W) portée par le porte-tranche (10), ladite lumière d'éclairage présentant la caractéristique d'être imprégnée par rapport à un matériau constituant la tranche (W) ; d'une section de détection de lumière détectant la lumière émise par la tranche (W) exposée à la lumière d'éclairage ; et d'une section d'inspection inspectant si la tranche (W) présente une anomalie, sur la base des signaux de détection de la lumière détectée au moyen de la section de détection de lumière. L'appareil est également pourvu de sections d'entraînement de bras (13a-13h) modifiant les positions de retenue du porte-tranche (10) (sections de bras (12a-12h)) par rapport à la tranche (W).
PCT/JP2012/066154 2011-06-27 2012-06-25 Procédé d'évaluation de motif, appareil d'évaluation de motif et procédé de fabrication d'un dispositif à semi-conducteur WO2013002179A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2011141984 2011-06-27
JP2011-141984 2011-06-27

Publications (1)

Publication Number Publication Date
WO2013002179A1 true WO2013002179A1 (fr) 2013-01-03

Family

ID=47424071

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/066154 WO2013002179A1 (fr) 2011-06-27 2012-06-25 Procédé d'évaluation de motif, appareil d'évaluation de motif et procédé de fabrication d'un dispositif à semi-conducteur

Country Status (3)

Country Link
JP (1) JPWO2013002179A1 (fr)
TW (1) TW201304029A (fr)
WO (1) WO2013002179A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014116878A1 (fr) * 2013-01-23 2014-07-31 Rudolph Technologies, Inc. Caractérisation d'un processus de microfabrication de tsv et produits
WO2015035923A1 (fr) * 2013-09-11 2015-03-19 International Business Machines Corporation Structure d'interconnexion verticale et procédé permettant d'améliorer des performances diélectriques beol
CN108630561A (zh) * 2017-03-15 2018-10-09 北京北方华创微电子装备有限公司 基片表面的检测装置和检测方法、传片腔室

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003297888A (ja) * 2002-03-26 2003-10-17 Isoa Inc 光学的検査方法及び光学的検査システム
JP2006184177A (ja) * 2004-12-28 2006-07-13 Mitsubishi Electric Corp 赤外検査装置及び赤外検査方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4655644B2 (ja) * 2005-01-26 2011-03-23 凸版印刷株式会社 周期性パターンのムラ検査装置
JP4878907B2 (ja) * 2006-05-08 2012-02-15 三菱電機株式会社 画像検査装置およびこの画像検査装置を用いた画像検査方法
JP5128920B2 (ja) * 2007-12-03 2013-01-23 芝浦メカトロニクス株式会社 基板表面検査装置及び基板表面検査方法
CN101990636A (zh) * 2008-04-09 2011-03-23 株式会社尼康 表面检查方法和表面检查装置
EP2280269A3 (fr) * 2009-07-30 2011-02-23 University-Industry Cooperation Group Of Kyung Hee University Analyse non destructive pour structure périodique

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003297888A (ja) * 2002-03-26 2003-10-17 Isoa Inc 光学的検査方法及び光学的検査システム
JP2006184177A (ja) * 2004-12-28 2006-07-13 Mitsubishi Electric Corp 赤外検査装置及び赤外検査方法

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014116878A1 (fr) * 2013-01-23 2014-07-31 Rudolph Technologies, Inc. Caractérisation d'un processus de microfabrication de tsv et produits
CN105051485A (zh) * 2013-01-23 2015-11-11 鲁道夫科技公司 表征tsv微制造过程及其产品
KR20150141934A (ko) * 2013-01-23 2015-12-21 루돌프 테크놀로지스 인코퍼레이티드 Tsv 마이크로 제조 프로세스 및 제품들의 특성화
US9952041B2 (en) 2013-01-23 2018-04-24 Rudolph Technologies, Inc. Assessing alignment of top and bottom ends of TSVs and characterizing microfabrication process
CN105051485B (zh) * 2013-01-23 2018-05-04 鲁道夫科技公司 表征tsv微制造过程及其产品
KR20210006518A (ko) * 2013-01-23 2021-01-18 루돌프 테크놀로지스 인코퍼레이티드 Tsv 마이크로 제조 프로세스 및 제품들의 특성화
KR102337617B1 (ko) * 2013-01-23 2021-12-08 루돌프 테크놀로지스 인코퍼레이티드 Tsv 마이크로 제조 프로세스 및 제품들의 특성화
KR102389680B1 (ko) * 2013-01-23 2022-04-21 루돌프 테크놀로지스 인코퍼레이티드 Tsv 마이크로 제조 프로세스 및 제품들의 특성화
WO2015035923A1 (fr) * 2013-09-11 2015-03-19 International Business Machines Corporation Structure d'interconnexion verticale et procédé permettant d'améliorer des performances diélectriques beol
CN108630561A (zh) * 2017-03-15 2018-10-09 北京北方华创微电子装备有限公司 基片表面的检测装置和检测方法、传片腔室

Also Published As

Publication number Publication date
JPWO2013002179A1 (ja) 2015-02-23
TW201304029A (zh) 2013-01-16

Similar Documents

Publication Publication Date Title
US10460998B2 (en) Method for inspecting substrate, substrate inspection apparatus, exposure system, and method for producing semiconductor device
JP6036680B2 (ja) 検査装置および半導体装置の製造方法
US6774987B2 (en) Surface inspection method, surface inspection apparatus, and recording medium and data signal for providing surface inspection program
WO2012115012A1 (fr) Dispositif d'observation, dispositif d'inspection, procédé de fabrication d'un dispositif à semi-conducteur et élément de support de substrat
JP5787261B2 (ja) 検査装置、及び検査方法
JP2007095881A (ja) アライメント装置および外観検査装置
WO2013002179A1 (fr) Procédé d'évaluation de motif, appareil d'évaluation de motif et procédé de fabrication d'un dispositif à semi-conducteur
JP5500427B2 (ja) 表面検査装置および表面検査方法
JP2004006504A (ja) バンプ検査方法及び装置
JP2006250843A (ja) 表面検査装置
JP2013205367A (ja) 検査装置、検査方法、およびデバイス製造方法
JP5257759B2 (ja) 検査装置および検査方法
JP2009300139A (ja) 検査装置
JP5994308B2 (ja) 検査装置、検査方法、およびデバイス製造方法
JP2004096078A (ja) アライメント装置
JP2009031125A (ja) 基板検査装置
JP2013140187A (ja) 検査装置
JP2011141135A (ja) 表面検査装置
JP5252286B2 (ja) 表面検査方法、表面検査装置および検査方法
JP2010025657A (ja) 検査装置
JP2009300141A (ja) 検査装置
JP2011141137A (ja) 表面検査装置
JP2009229155A (ja) 基板検査装置、およびマスク用基板の製造方法
JP2012163422A (ja) 検査装置
JP2011085493A (ja) 表面検査装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12803713

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2013522845

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12803713

Country of ref document: EP

Kind code of ref document: A1