JP2002195956A - Failure inspecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple and small configuration while devices for macro inspection and partial magnification inspection are integrated for a unit configuration. SOLUTION: A failure inspecting device comprises a lighting optical system 10 which projects an optical flux from a light source onto a wafer W at a prescribed incident angle, a low-magnification focusing lens 21 which receives the reflection light from the wafer W, a low-magnification imaging element 22 which images a wafer image focused by the low-magnification focusing lens 21, a high-magnification focusing lens 31 which receives the reflection light from the wafer, and a high-magnification imaging element 32 which images a wafer image focused by the high-magnification focusing lens 31. Based on the image information of the wafer imaged by both imaging elements 22 and 32, the failure of the object to be inspected is inspected. Related to the failure inspecting device, a sight field of the high-magnification focusing lens 31 and the imaging element 32 for a wafer can be moved in two-dimensional manner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defect inspection apparatus for detecting a defect on the surface of a substrate in a process of manufacturing a semiconductor device or the like. The present invention relates to a defect inspection device.

[0002]

2. Description of the Related Art Semiconductor wafers and liquid crystal display element panels (collectively referred to as semiconductor wafers and the like) are formed by arranging a large number of circuit element patterns on the surface.
Each circuit element pattern has extremely thin wiring, extremely small circuit elements, and the like.If a surface defect exists on a semiconductor wafer or the like, the performance of a chip or a panel including the circuit element pattern is impaired. Inspection is very important.

Various such surface defect devices or methods have been proposed in the prior art.
There is an apparatus disclosed in Japanese Patent Publication No. 874. In this apparatus, an illumination optical system for scattered light and an illumination optical system for diffracted light are provided, and the presence or absence of a surface defect is inspected from scattered light and diffracted light from a substrate (such as a semiconductor wafer).

Further, Japanese Patent Application Laid-Open No. 11-230917 discloses a macro inspection unit for photographing a low-magnification image to inspect the entire surface of a semiconductor wafer or the like for defects, and a macro-magnification unit for photographing a high-magnification image. There is disclosed a defect inspection apparatus including a review inspection unit for inspecting a defective portion in an enlarged manner. According to this defect inspection apparatus, when the entire surface of a semiconductor wafer or the like is collectively inspected by the macro inspection unit and a defect or the like is found, the semiconductor wafer or the like is transported to the review inspection unit, and the defective portion is enlarged and detailed. There is an advantage that can be observed.

[0005]

However, in such a defect inspection apparatus, a macro inspection unit and a review inspection unit are provided, respectively, and a transport unit for transporting a semiconductor wafer or the like to be inspected between both units is provided. is necessary. In addition, the review inspection unit allows you to accurately magnify and photograph defective parts.
There is also a need for a positioning / transporting unit that moves and positions the semiconductor wafer or the like so as to accurately position a defective portion of the semiconductor wafer or the like to be inspected directly below the objective lens of the high-magnification imaging apparatus. Therefore, there is a problem that the configuration of the defect inspection apparatus is easily complicated and large, and the cost of the apparatus is easily increased.

The present invention has been made in view of such a problem.
It is an object of the present invention to provide a defect inspection apparatus which can have a unit configuration in which an apparatus for performing a macro inspection and a partial enlargement inspection is integrated, and has a relatively simple and small configuration. Another object of the present invention is to provide a defect inspection apparatus capable of performing macro inspection and enlarged inspection of an arbitrary portion as they are while holding a test object fixed.

[0007]

According to the present invention, there is provided a table on which a test object is placed, and an illumination optical system for irradiating the test object with a light beam from a light source at a predetermined incident angle. System, a low-magnification light-receiving optical system that receives reflected light (specular reflection light, diffracted light, scattered light, etc.) from the object on the table, and a test object imaged by the low-magnification light-receiving optical system Low-magnification imager that captures the image of the subject, a high-magnification light-receiving optical system that receives reflected light from the same test object on the table, and an image of the test object formed by the high-magnification light-receiving optical system A defect inspection apparatus is configured to include a high-magnification imager that photographs a subject, and a field-of-view moving device that two-dimensionally moves the field of view of the object to be inspected by at least a high-magnification light receiving optical system. Based on image information of the test object captured by the magnification imager A defect inspection of the inspected object.

As described above, according to the present invention, the defect inspection apparatus
A unit (low-magnification light-receiving optical system and low-magnification imager) that performs low-magnification inspection (macro inspection) based on light reflected from the object under illumination from the illumination optical system. A unit (high-magnification receiving optical system and high-magnification imager) for performing a high-magnification inspection (magnification inspection or review inspection) based on the object to be inspected on one table by selectively using both units The device is configured to perform inspections.
It can be made compact.

The low-magnification inspection can inspect the whole surface of the object at once, while the high-magnification inspection inspects a predetermined position on the surface of the object. The defect inspection apparatus of the present invention has a visual field moving device that two-dimensionally moves the visual field of the high-magnification light receiving optical system with respect to the object to be inspected, and moves the visual field of the high-magnification light receiving optical system with this visual field moving device. By simply doing so, an arbitrary position on the surface of the test object can be easily enlarged and inspected. In other words, there is no need for a transport device that transports a relatively large test object having a complicated configuration, and the entire device can be reduced in size and size. Further, when the entire surface cannot be inspected at once by the low-magnification light receiving optical system, the visual field moving device may be configured to two-dimensionally move the visual field of the low-magnification light receiving optical system. .

According to another aspect of the present invention, there is provided an illumination optical system for irradiating a light beam from a light source to a test object at a predetermined incident angle, and a low-magnification light receiving optical system for receiving reflected light from the test object. A low-magnification imager that captures an image of the test object formed by the low-magnification light-receiving optical system, a high-magnification light-receiving optical system that receives light reflected from the test object, and a high-magnification light-receiving optical system And a high-magnification imager for photographing an image of the test object formed by the system.The defect inspection apparatus is configured based on image information of the test object photographed by the low-magnification imager and the high-magnification imager. The defect inspection of the object to be inspected is performed. This defect inspection apparatus has a field-of-view moving device that at least two-dimensionally moves the field of view of the object with a high-magnification light-receiving optical system, and further receives and condenses reflected light from the object to be measured. An optical system is provided, and a low-magnification light-receiving optical system and a high-magnification light-receiving optical system are arranged such that the entrance pupil is located substantially in the focal plane of the light-collecting optical system.

The condensing optical system includes a condensing lens for receiving and condensing light reflected from the object to be inspected, and a concave mirror for receiving and reflecting and condensing light reflected from the object to be inspected. A low-magnification light-receiving optical system and a high-magnification light-receiving optical system are arranged such that the entrance pupil is located substantially within the focal plane of these condenser lenses or concave mirrors.

Also in the present invention, the defect inspection apparatus
A unit (low-magnification light-receiving optical system and low-magnification imager) that performs low-magnification inspection (macro inspection) based on light reflected from the object under illumination from the illumination optical system. And a unit (high-magnification light-receiving optical system and high-magnification imager) for performing a high-magnification inspection (magnification inspection or review inspection) based on the system. be able to.

It is preferable that the field-of-view moving device has a swing mechanism for swinging the high-magnification light receiving optical system two-dimensionally around the center of the entrance pupil of the high-magnification light receiving optical system. .

According to still another aspect of the present invention, an illumination optical system for irradiating a test object with a light beam from a light source at a predetermined incident angle, and a low-magnification light receiving optical system for receiving light reflected from the test object A low-magnification imager that captures an image of the test object formed by the low-magnification light-receiving optical system, a high-magnification light-receiving optical system that receives light reflected from the test object, and a high-magnification light-receiving optical system And a high-magnification imager for photographing an image of the test object formed by the system.The defect inspection apparatus is configured based on image information of the test object photographed by the low-magnification imager and the high-magnification imager. The defect inspection of the object to be inspected is performed. The defect inspection apparatus further includes a test object moving apparatus for moving the test object one-dimensionally in a first direction within the test plane while maintaining the position of the test plane, and at least a high magnification light receiving optical system. A field-of-view moving device for one-dimensionally moving a field of view with respect to the inspection object in a second direction substantially orthogonal to the first direction.

In the present invention, the defect inspection apparatus is
A unit (low-magnification light-receiving optical system and low-magnification imager) that performs low-magnification inspection (macro inspection) based on light reflected from the object under illumination from the illumination optical system. And a unit (high-magnification light-receiving optical system and high-magnification imager) for performing a high-magnification inspection (magnification inspection or review inspection) based on the system. be able to.

According to the present invention, there is also provided a device for moving a test object one-dimensionally in a first direction within the test surface while maintaining the position of the test surface, and at least a high-magnification light receiving optical system. A field-of-view moving device for one-dimensionally moving the field of view with respect to the test object in a second direction substantially orthogonal to the first direction, the device having a simple configuration for moving the test object in a one-dimensional manner An arbitrary position on the surface of the object to be inspected can be easily inspected by using a simple apparatus that one-dimensionally moves the visual field of the object to be inspected by the high-magnification light receiving optical system.

In the present invention, a condensing optical system for receiving and condensing the reflected light from the object to be inspected may be provided. In this case, the entrance pupil is located substantially within the focal plane of the condensing optical system. Are arranged such that the light receiving optical system of low magnification and the light receiving optical system of high magnification are located. In addition, as the light collecting optical system, there are a light collecting lens that receives and condenses reflected light from a test object, and a concave mirror that receives light reflected from a test object and reflects and condenses the light.

The field-of-view moving device can be configured to have a swinging mechanism for swinging the high-magnification light receiving optical system one-dimensionally around the center of the entrance pupil of the high-magnification light receiving optical system. .

In the defect inspection apparatus according to the present invention having the above-described configuration, it is preferable to provide a display device for displaying an image of the test object captured by the low-magnification imager and the high-magnification imager. Further, the object to be inspected is a semiconductor wafer or the like, and the illumination optical system is configured to irradiate the surface of the semiconductor wafer or the like with a light beam from a light source at a large incident angle as a parallel light beam. It is preferable to provide a wafer support table for rotating a semiconductor wafer or the like while holding the wafer at the same plane position.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of a defect inspection apparatus to which the present invention is applied. For simplicity of description, a direction perpendicular to the paper surface in FIG. 1 is defined as a Y direction, a direction extending left and right is defined as an X direction, and a direction extending vertically is defined as a Z direction, as indicated by arrows X and Z.

This defect inspection apparatus includes:
It comprises an illumination optical system 10, a low-magnification inspection unit 20, a high-magnification inspection unit 30, and a wafer support table 50 for mounting and holding a wafer W to be inspected.
Opening / closing door 2 for loading / unloading wafer W into / from chamber 1
An opening 1a which is opened / closed is formed, so that a wafer W can be loaded and unloaded onto the wafer support table 50 by a transfer device (not shown) such as a robot arm. In addition, when the surface inspection is performed, the opening 1a is closed by the opening / closing door 2, so that stray light from the outside is blocked, thereby enabling an efficient inspection.

The wafer W is placed horizontally on the wafer support table 50 with the inspection surface facing upward as shown in the figure, and is fixed and held by vacuum suction or the like. The wafer support table 50 is rotatable in a horizontal plane by a drive mechanism 51, and the wafer W is rotated while the inspection surface is located on the same horizontal plane.

The illumination optical system 10 houses a light source such as a halogen lamp or a metal halide lamp, and includes a lamp house 11 having a lens and an exchangeable wavelength selection filter, and uses only light in a specific wavelength range. I can do it. The light from the lamp house 11 passes through the light guide 12 and strikes the wafer W at an incident angle of 80 to 90 degrees.
Light in degrees. The shape of the exit side end surface 12a of the light guide 12 is a slit shape in which the direction perpendicular to the paper surface (Y direction) is long and the direction perpendicular to the longitudinal direction is short. The slit-shaped light beam emitted from the emission-side end surface 12a of the light guide 12 is converted by the cylindrical lens 3 into substantially parallel light in a plane in the short direction of the slit. Thus, the light emitted from the end surface 12a of the light guide 12 efficiently illuminates the entire surface of the wafer. Thus, the incident angle is 80 degrees to 90 degrees.
Since it is large, the length of the cylindrical lens 13 in the lateral direction can be reduced.

When light is irradiated from the illumination optical system 10 as described above, if there is a defect such as a foreign matter or a scratch on the surface of the wafer W, scattered light is generated. The scattered light is received by a condenser lens 5 (corresponding to a condenser optical system in the claims) disposed above and opposed to the wafer support table 50. The optical axis of the condenser lens 5 is parallel to the normal line of the wafer W.

A low-magnification inspection unit 20 and a high-magnification inspection unit 30 are arranged above the condenser lens 5 side by side. The low-magnification inspection unit 20 includes a low-magnification imaging lens 21.
The high-magnification inspection unit 30 is composed of a high-magnification imaging lens 31 and a high-magnification imaging element 32. The imaging lens 21, Both inspection units 20 and 30 are arranged such that 31 entrance pupils are located. That is, the condenser lens 5 and the quantity inspection units 20 and 30
Is an optical system whose object side is telecentric.

The low-magnification inspection unit 20 is disposed so as to have a central optical axis coaxially with the central optical axis of the condenser lens 5, and only the light scattered substantially in the normal direction of the wafer W is provided.
Foreign matter collected by the imaging lens 21 and scattered light,
An image of the flaw is formed on the low-magnification image sensor 22. Further, only the light scattered in a predetermined angle direction viewed from the normal line of the wafer W is condensed through the imaging lens 21, and the image of the foreign matter and the flaw due to the scattered light is formed on the image sensor 22. You.

At this time, if a repetitive pattern is formed on the wafer W, the wafer support table 50 is appropriately rotated by the table rotation driving device 51 so that the diffracted light generated by the repetitive pattern does not enter the light receiving optical system.
When the same pattern is formed all over the wafer W, the diffraction angle of the diffracted light becomes the same at any position on the wafer W, and when the wafer W is rotated, the diffraction angle changes uniformly. In the case of a non-telecentric optical system, the angle of the scattered light condensed by the light receiving optical system differs depending on the position on the wafer, so that even if the wafer W is rotated, the mixture may remain in a part of the wafer W. . Therefore, a telecentric optical system as in this example is more convenient. In addition, as the light collecting optical system, a reflecting optical element such as a spherical reflecting mirror may be used in place of the light collecting lens 5, which will be described later.

The image pickup devices 22 and 32 are two-dimensional sensors, for example, CCDs. Low magnification image sensor 22
In order to be able to image the entire surface of the wafer W,
The focal length of the low-magnification imaging lens 21 and the size of the low-magnification image sensor 22 are set. On the other hand, in the high-magnification imaging device 32, the focal length of the high-magnification imaging lens 31 and the size of the high-magnification imaging device 32 are adjusted so that an image obtained by enlarging a predetermined portion of the range that can be captured by the low-magnification imaging device 22 is obtained. Is set. Further, the two imaging lenses 21 and 31 are not limited to lenses having a fixed focal length, but may be zoom lenses or varifocal lenses. The magnification can be changed according to the size of a foreign object or a flaw to be inspected. Efficient inspection becomes possible.

The high-magnification inspection unit 30 includes a unit case 33 integrally holding a high-magnification imaging lens 31 and a high-magnification image sensor 32, and a swing actuator. The unit case 33 is supported via a spherical bush or the like so as to be swingable in all directions (360 degrees) around the center of the entrance pupil of the high-magnification imaging lens 31. It is configured to be dynamically controlled. By this swing control, the optical axis direction of the high-magnification inspection unit 30 can be arbitrarily set variably.
It is possible to enlarge an arbitrary portion on the surface of the camera and photograph it.

The image signals picked up by the two image pickup devices 22 and 32 are sent to a display device 41 composed of a CRT, a liquid crystal panel display or the like, where the image of a defect such as a foreign substance or a scratch is displayed. At this time, the images from the image sensors 22 and 32 can be switched and displayed on the screen of the display device 41. An image processing device 42 is provided so as to be connected to the display device 41. The image processing device 42 processes the image captured by the imaging elements 22 and 32, and displays information such as the position and size of a defect on the display device 41 and the display device 41. It is sent to the arithmetic unit 43. Therefore, the display device 41 can also display such defect information.

The operation control signal is sent from the arithmetic unit 43 to the drive mechanism 51 to control the rotational drive of the wafer support table 50, and further, a control signal is sent to the swing control unit 45 to increase the high magnification by the swing actuator 34. Inspection unit 3
The swing control of 0 is performed.

Next, a procedure for performing a collective inspection of the surface of the wafer W and then observing a defective portion with the inspection apparatus having the above configuration will be described with reference to a flowchart of FIG.
First, an image based on the scattered light of the entire surface of the wafer W is photographed by the low-magnification inspection unit 20, and the image is displayed on the display device 4.
1 (step S1). At the same time, the image processing device 42 detects a surface defect (step S2), calculates its position and size, and sends the information to the display device 41 and the arithmetic device 43 (step S3). In response to this, the display device 41 displays the preceding information on the image of the entire wafer (step S4). On the other hand, the arithmetic unit 43 includes the image processing unit 42
The swing direction and swing amount of the high-magnification inspection unit 34 required to bring the defect portion into the field of view that can be captured by the high-magnification image sensor 32 are calculated from the position of the defect sent from The information is transmitted to the swing control device 45 (step S5). The swing control device 45 drives the swing actuator 34 based on this information (step S6), captures an image of the defective portion enlarged by the high-magnification image sensor 32, and enlarges the defective portion thus captured. Is displayed on the display device 41 (step S7). At this time, if the high-magnification imaging lens 31 is a zoom lens, the magnification is changed according to the size of the defect.

Next, a procedure for detecting a small defect will be described with reference to the flowchart of FIG. In this case, the inspection procedure is such that small defects are first inspected by the high magnification inspection unit 30 and whole display is performed by the low magnification inspection unit 20 after the defect is detected. For this reason, first, based on the size of the field of view of the enlarged image captured by the high-magnification image sensor 32, the region on the wafer W is divided into n regions by the arithmetic unit 43 (step S11), and a predetermined region is High magnification inspection unit 3 necessary for imaging
The swing amount of 0 is calculated, and the information is transmitted to the swing control device 45 (step S12). The swing control device 45 drives the swing actuator 34 based on this information (step S13), captures an enlarged image of the predetermined area with the high-magnification image sensor 32, and displays this on the display device 10 (step S14). ). In this case, the imaging resolution is higher than in the case where the inspection with the whole image of the wafer surface is performed by the low-magnification inspection unit 20, so that a smaller defect can be detected.

Here, when the image processing device 42 performs image processing and detects a defect, the position and size are calculated and the information is stored (step S15). Next, returning from step S16 to step S12, the arithmetic unit 43 calculates the swing amount of the high-magnification inspection unit 30 for moving to the next inspection area, and transmits the calculated amount to the swing control unit 45. Thereby, the swing control device 45 controls the swing of the swing actuator 34 to swing the high-magnification inspection unit 30, and photographs the next inspection area by the high-magnification image sensor 32, and performs the same defect inspection processing as described above. I do. This operation is performed over all n regions (that is, over the entire surface of the wafer W).
Do.

When it is determined in step S16 that the inspection over the entire area has been completed, the process proceeds to step S17, where the display device 41 switches to the image from the low-magnification image sensor 22 to display the image of the entire surface of the wafer W,
Here, the position of the defect stored by the image processing device 42,
The size is sent to the display device 41, and the preceding information is displayed on the image of the entire wafer (step S18). If it is desired to further observe the defective portion, the display is switched to an enlarged image of the defective portion. If the high-magnification imaging lens 31 is a zoom lens,
The magnification is changed according to the size of the defect.

Next, a defect inspection apparatus according to a second embodiment of the present invention will be described with reference to FIG. In this embodiment, the same parts as those in the first embodiment will be described using the same reference numerals as those in the first embodiment. In the present embodiment, the condensing lens 5 in the first embodiment constituting the condensing optical system according to the claims is replaced by a concave spherical reflecting mirror 8. The use of a large-diameter condenser lens 5 composed of a refractive lens as in the first embodiment increases the size of the apparatus. Therefore, in this embodiment, a reflection-type optical element composed of a spherical reflecting mirror 8 is used as a condenser optical system. The size of the device is reduced by using it. Also, since it is a spherical reflecting mirror, no chromatic aberration occurs, which is convenient.

This defect inspection apparatus also includes an illumination optical system 10, a low-magnification inspection unit 20, a high-magnification inspection unit 30, and an object to be inspected in a chamber 1 having an opening 1a opened and closed by an opening and closing door 2. And a wafer support table 50 for mounting and holding a wafer W to be formed. However,
In this apparatus, as shown in FIG.
Above, a spherical reflecting mirror 8 is provided in place of the condenser lens 5. The wafer W is placed horizontally on the wafer support table 50 so that the inspection surface faces upward, and is fixed and held by vacuum suction or the like.
Is rotatable in a horizontal plane by a drive mechanism 51.

The illumination optical system 10 accommodates a light source such as a halogen lamp or a metal halide lamp, and includes a lamp house 11 having a lens and an exchangeable wavelength selection filter. , The wafer W is illuminated at an incident angle of 80 to 90 degrees. The exit side end face 12a of the light guide 12 is shaped like a slit whose direction perpendicular to the plane of the drawing (Y direction) is long. , And the light emitted from the end face 12a of the light guide 12 efficiently illuminates the entire surface of the wafer.

When light is irradiated from the illumination optical system 10 as described above, if there is a defect such as a foreign matter or a scratch on the surface of the wafer W, scattered light is generated. The light is received, reflected, and condensed by the spherical reflecting mirror 8 disposed above and opposed thereto.

The low-magnification inspection unit 20 and the high-magnification inspection unit 30 are arranged side by side at the position where the light reflected and condensed by the spherical reflecting mirror 8 is received.
The low-magnification inspection unit 20 includes a low-magnification imaging lens 21 and a low-magnification imaging device 22, and the high-magnification inspection unit 30 includes a high-magnification imaging lens 31 and a high-magnification imaging device 32.
And at a position substantially within the focal plane of the spherical reflecting mirror 8,
Both inspection units 20 and 30 are arranged so that the entrance pupils of the imaging lenses 21 and 31 are located. That is, in this apparatus, the optical system including the spherical reflecting mirror 8 and the quantity inspection units 20 and 30 is an optical system whose object side is telecentric.

The low-magnification inspection unit 20 is disposed so as to have the center normal axis of the wafer W and the target optical axis with the center optical axis of the spherical reflecting mirror 8 interposed therebetween, and to be almost normal to the wafer W. Only the scattered light is condensed through the imaging lens 21, and an image of a foreign substance or a flaw due to the scattered light is formed on the low-magnification image sensor 22. Further, only the light scattered in a predetermined angular direction viewed from the normal line of the wafer W is condensed through the imaging lens 31, and an image of a foreign substance or a flaw due to the scattered light is formed on the image sensor 32. You. At this time, if a repetitive pattern is formed on the wafer W, the wafer support table 50 is appropriately rotated so that diffracted light generated by the repetitive pattern does not enter the light receiving optical system.

The imaging elements 22 and 32 are, for example, CCDs. The low-magnification imaging element 22 captures an image of the entire surface of the wafer W. The high-magnification imaging element 32 has a range that can be captured by the low-magnification imaging element 22. The setting is such that an image obtained by enlarging a predetermined portion is obtained. Note that the imaging lens 21 or 31 may be a zoom lens or a varifocal lens, and efficient inspection can be performed by changing the magnification according to the size of a foreign object or a flaw to be inspected.

The high-magnification inspection unit 30 is omnidirectional (360) around the center of the entrance pupil of the high-magnification imaging lens 31.
The unit case 33 is supported via a spherical bush or the like so as to be swingable in degrees.
4 is configured to be controlled to swing. By the swing control, the optical axis direction of the high-magnification inspection unit 30 can be arbitrarily set variably.
2, an arbitrary portion on the surface of the wafer W can be enlarged and photographed.

The image signals photographed by the two image pickup devices 22 and 32 are sent to a display device 41 composed of a CRT, a liquid crystal panel display, or the like, where the image of a defect such as a foreign substance or a scratch is displayed. An image processing device 42 is provided so as to be connected to the display device 41.
Performs processing of the image captured by the imaging devices 22 and 32,
Information such as the position and size of the defect is sent to the display device 41 and the arithmetic device 43. Therefore, the display device 41 can also display such defect information.

The rotation control of the wafer support table 50 is controlled by sending an operation control signal from the arithmetic unit 43 to the drive mechanism 51, and a control signal is sent to the swing control unit 45 to increase the high magnification by the swing actuator 34. Inspection unit 3
The swing control of 0 is performed.

Next, the procedure of performing a collective inspection of the surface of the wafer W and then observing the defective portion by the inspection apparatus having the above-described configuration is the same as that of the apparatus shown in FIG. 1, and this will be briefly described. First, the low magnification inspection unit 20 displays an image based on the scattered light of the entire surface of the wafer W on the display device 41, and at the same time, the image processing device 42 detects a surface defect,
The information is sent to the display device 41 and the arithmetic device 43. In response to this, the display device 41 displays the previous information on the image of the entire wafer, and the arithmetic device 43 indicates that the defective portion has a high-magnification image sensor 32.
The swing direction and the swing amount of the high-magnification inspection unit 34 required to enter the field of view that can be captured by the camera are calculated, and the information is transmitted to the swing control device 45. The swing control device 45 drives the swing actuator 34 based on this information, takes an image of the defective portion enlarged by the high-magnification image sensor 32, and displays the enlarged image of the defective portion thus taken on the display device 41. Will be displayed.

Next, a procedure for detecting a small defect will be briefly described. First, in the arithmetic unit 43, the wafer W
The upper region is divided into n regions, the amount of swing of the high-magnification inspection unit 30 required to image a predetermined region is calculated, and the information is transmitted to the swing controller 45. The swing control device 45 drives the swing actuator 34 based on this information, captures an enlarged image of the predetermined area by the high-magnification image sensor 32, and causes the display device 10 to display the enlarged image. If a defect is detected by the image processing of the image processing device 42, the information is stored.

Next, the arithmetic unit 43 calculates the swing amount of the high-magnification inspection unit 30 for moving to the next inspection area, and the swing control unit 45 controls the swing of the swing actuator 34 to control the high-magnification. The inspection unit 30 is rocked, the next inspection area is photographed by the high-magnification image sensor 32, and the same defect inspection processing as described above is performed. This operation is performed over all n regions (that is, over the entire surface of the wafer W).

Thereafter, the display device 41 switches to the image from the low-magnification image sensor 22 to display an image of the entire surface of the wafer W. Here, the image processing device 42 displays the stored defect information on the display device 41. To display the preceding information on the image of the entire wafer. If the defect portion is to be further magnified and observed, the image is switched to an enlarged image of the defect portion. If the high-magnification imaging lens 31 is a zoom lens, the magnification is changed to the size of the defect.

In the defect inspection apparatuses according to the first and second embodiments described above, the high-magnification inspection unit 30 is omnidirectionally (two-dimensionally) centered on the center of the entrance pupil of the high-magnification imaging lens 31. ) Although it is configured to be swingable, a similar configuration may be used for the low magnification inspection unit 20.
This is particularly suitable when the size of the wafer W is large and it is difficult to image the front surface of the wafer W at once with the low magnification inspection unit 20.

The high-magnification inspection unit 30 is one-dimensionally centered on the center of the entrance pupil of the high-magnification imaging lens 31,
That is, it can be swung in a predetermined plane including the optical axis,
The wafer support table 50 may be configured to be linearly movable in the direction of the wafer surface in a plane orthogonal to the predetermined plane. Thereby, the one-dimensional swing of the high-magnification inspection unit 30 and the linear movement of the wafer support table 50 are controlled, and an arbitrary portion on the entire surface of the wafer W is moved to the high-magnification image sensor 3.
2 can be taken. In this case, since the swing of the high-magnification inspection unit 30 and the linear movement of the wafer support table 50 are also one-dimensional movements, the mechanism and operation control thereof are simple. The high-magnification inspection unit 30 is fixedly provided so that the optical axis of the high-magnification imaging lens 31 is perpendicular to the table surface of the wafer support table 50, and is controlled so as to move the table 50 two-dimensionally. May be.

In the defect inspection apparatus described above, the defect inspection is performed based on the scattered light emitted from the wafer surface when the wafer surface is illuminated. The defect inspection may be performed based on the defect inspection.

[0053]

As described above, the defect inspection apparatus is
A unit (low-magnification light-receiving optical system and low-magnification imager) that performs low-magnification inspection (macro inspection) based on light reflected from the object under illumination from the illumination optical system. And a unit (high-magnification light-receiving optical system and high-magnification imager) for performing a high-magnification inspection (magnification inspection or review inspection) based on the system. be able to.

Note that the low-magnification inspection can inspect the entire surface of the object at once, while the high-magnification inspection inspects a predetermined position on the surface of the object. The defect inspection apparatus of the present invention has a visual field moving device that two-dimensionally moves the visual field of the high-magnification light receiving optical system with respect to the object to be inspected, and moves the visual field of the high-magnification light receiving optical system with this visual field moving device. By simply doing so, an arbitrary position on the surface of the test object can be easily enlarged and inspected. In other words, there is no need for a transport device that transports a relatively large test object having a complicated configuration, and the entire device can be reduced in size and size.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a defect inspection device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of a defect inspection apparatus according to a second embodiment of the present invention.

FIG. 3 is a flowchart showing an inspection procedure by the defect inspection apparatus of the present invention.

FIG. 4 is a flowchart showing another inspection procedure by the defect inspection apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chamber 5 Condensing lens 8 Spherical reflecting mirror 10 Illumination optical system 11 Lamp house 12 Light guide 13 Cylindrical lens 20 Low magnification inspection unit 21 Low magnification imaging lens 22 Low magnification imaging device 30 High magnification inspection unit 31 High magnification imaging lens Reference Signs List 32 High-magnification imaging device 34 Swing actuator 41 Display device 42 Image processing device 43 Arithmetic device 45 Swing control device 50 Wafer support table W Wafer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA49 BB02 CC17 CC19 FF04 FF42 GG02 HH12 JJ03 JJ09 JJ26 LL01 LL08 LL19 LL22 LL59 MM04 MM24 PP13 QQ24 QQ31 SS13 2G051 AA51 AB07 AC02 BB01 CC03 DA03 CB01 DA03

Claims (8)

[Claims] 1. A table on which a test object is placed, an illumination optical system for irradiating a light beam from a light source to the test object at a predetermined incident angle, and a reflected light from the test object on the table A low-magnification light-receiving optical system for receiving light, a low-magnification imager for taking an image of the test object formed by the low-magnification light-receiving optical system, and reflection from the same test object on the table A high-magnification light-receiving optical system for receiving light; a high-magnification imager for photographing an image of the test object formed by the high-magnification light-receiving optical system; A field-of-view moving device that two-dimensionally moves the field of view with respect to the inspection object; and a defect of the inspection object based on image information of the inspection object captured by the low-magnification imaging device and the high-magnification imaging device. A defect inspection device for performing an inspection. 2. An illumination optical system for irradiating a test object with a light beam from a light source at a predetermined incident angle; a low-magnification light-receiving optical system for receiving reflected light from the test object; A low-magnification imager that captures an image of the test object formed by an optical system, a high-magnification light-receiving optical system that receives reflected light from the test object, and an image formed by the high-magnification light-receiving optical system And a high-magnification imager for photographing the image of the object to be imaged. The imager is configured based on image information of the object photographed by the low-magnification imager and the high-magnification imager. In a defect inspection apparatus that performs a defect inspection of an inspection object, a defect inspection apparatus that has a field-of-view moving device that two-dimensionally moves a field of view of the high-magnification light receiving optical system with respect to the object to be inspected, A light collecting optical system for receiving and collecting light is provided. Serial condensing optical system defect inspection apparatus characterized substantially in that the low magnification of the light receiving optical system and the high magnification of the light-receiving optical system so that the incident pupil is located in the focal plane is disposed of. 3. An illumination optical system for irradiating a test object with a light beam from a light source at a predetermined incident angle; a low-magnification light-receiving optical system for receiving light reflected from the test object; A low-magnification imager that captures an image of the test object formed by an optical system, a high-magnification light-receiving optical system that receives reflected light from the test object, and an image formed by the high-magnification light-receiving optical system And a high-magnification imager for photographing the image of the object to be imaged. The imager is configured based on image information of the object photographed by the low-magnification imager and the high-magnification imager. A defect inspection apparatus for inspecting a defect of an inspection object, comprising: a visual field moving device that two-dimensionally moves a visual field with respect to the test object of at least the high-magnification light receiving optical system; Center of the entrance pupil of the receiving optical system Defect inspection apparatus characterized by being configured with a swinging mechanism for swinging the receiving optical system of the high magnification in two dimensions. 4. An illumination optical system for irradiating a test object with a light beam from a light source at a predetermined incident angle, a low-magnification light receiving optical system for receiving light reflected from the test object, and the low-magnification light reception A low-magnification imager that captures an image of the test object formed by an optical system, a high-magnification light-receiving optical system that receives reflected light from the test object, and an image formed by the high-magnification light-receiving optical system And a high-magnification imager for photographing the image of the object to be imaged. The imager is configured based on image information of the object photographed by the low-magnification imager and the high-magnification imager. A defect inspection apparatus that performs a defect inspection of an inspection object, wherein the inspection object moving device that one-dimensionally moves the inspection object in a first direction within the inspection surface while maintaining the inspection surface position; High-magnification receiving optical system That defect inspection apparatus characterized by having a field of view moving device that moves one-dimensionally in a second direction substantially perpendicular to the first direction field. 5. A condensing optical system for receiving and condensing reflected light from the test object, wherein the low-magnification optical system is arranged such that an entrance pupil is located substantially within a focal plane of the condensing optical system. The defect inspection apparatus according to claim 4, wherein a light receiving optical system and the high magnification light receiving optical system are provided. 6. The field-of-view moving device includes a swing mechanism that swings the high-magnification light receiving optical system one-dimensionally around a center of an entrance pupil of the high-magnification light receiving optical system. The defect inspection apparatus according to claim 4 or 5, wherein 7. The defect according to claim 1, further comprising a display device that displays an image of the test object captured by the low-magnification imager and the high-magnification imager. Inspection equipment. 8. The object to be inspected comprises a semiconductor wafer or the like, and the illumination optical system irradiates the surface of the semiconductor wafer or the like with a light beam from the light source at a large incident angle as a parallel light beam, and irradiates the surface of the semiconductor wafer or the like. The defect inspection apparatus according to any one of claims 1 to 7, further comprising a wafer support table for rotating the semiconductor wafer or the like while maintaining the surface position at the same plane position.