JP2001135690A - Inspecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly attain microfine pattern inspection by validly preventing vibration generated in a clean box for maintaining an environment for inspection in a clean state from being transmitted to the device main body part. SOLUTION: A clean box 3 is supported by support means 70 arranged across a floor plate material 101 on which a device main body 10 is set. Thus, the clean box 3 is arranged on the floor plate material 101 different from the floor plate material 101 on which the device main body 10 is set so that vibration generated in the clean box 3 can be effectively prevented from being transmitted to the device main body 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an inspection apparatus used for inspecting a semiconductor wafer or the like on which a predetermined device pattern is formed.

[0002]

2. Description of the Related Art A semiconductor device is manufactured by forming a fine device pattern on a semiconductor wafer. When such a device pattern is formed, dust or the like may adhere to the semiconductor wafer or may be damaged, thereby causing a defect. A semiconductor device having such a defect becomes a defective device and reduces the yield.

[0003] Therefore, in order to stabilize the yield of a production line at a high level, defects generated by dust and scratches are found at an early stage, the causes thereof are identified, and effective measures are taken for production facilities and production processes. It is preferable to take it.

[0004] Therefore, when a defect is found, an inspection device is used to check the type of the defect and classify the defect, thereby identifying the equipment or process that caused the defect. I have. Here, the inspection device for checking what the defect is is like an optical microscope, so to speak.
By looking at a defect in an enlarged manner, it tries to identify what the defect is.

[0005]

When dust or the like adheres to the semiconductor wafer during the above-described inspection, an appropriate inspection cannot be performed. Therefore, the inspection of the semiconductor wafer needs to be performed in a clean environment.

As a method of keeping the environment for inspecting semiconductor wafers clean, a main body of the inspection apparatus is covered with a clean box, and clean air is supplied into the clean box to keep the inside of the clean box high. A method of keeping the degree of cleanness is effective. In this case, the semiconductor wafer to be inspected is transported in a sealed container, and the semiconductor wafer is transferred into a clean box via this container, so that the entire environment in which the inspection apparatus is installed is highly clean. Even if the temperature is not kept high, it is possible to effectively suppress the attachment of dust and the like on the semiconductor wafer, and to appropriately inspect the semiconductor wafer.

[0007] By the way, the device pattern of a semiconductor wafer to be inspected is becoming finer and finer with the increase in the degree of integration of semiconductor devices.
It has been reduced to 18 μm or less. In performing inspection of such a fine pattern, even a slight vibration may hinder the inspection. Therefore, it is required that such vibration is not transmitted to the main body of the inspection apparatus.

In particular, in many cases, vibration from a blower for supplying air to the inside of the clean box is transmitted to the clean box. Further, the clean box may be vibrated even when the inspector touches the clean box. If vibration generated in such a clean box is transmitted to the main body of the inspection device, it may become a factor that hinders proper inspection.Therefore, measures to prevent such vibration from being transmitted to the main body of the inspection device are taken. It is required to take.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and effectively suppresses transmission of vibration generated in a clean box for keeping an inspection environment clean to an apparatus main body. Accordingly, it is an object of the present invention to provide an inspection apparatus that can appropriately inspect a fine pattern.

[0010]

An inspection apparatus according to the present invention is an inspection apparatus installed in an installation space in which a plurality of floorboards are laid, and a clean box in which an internal environment is kept clean. An apparatus main body that is housed inside the clean box and inspects an object to be inspected, and a support member that supports the clean box are provided. The inspection apparatus is characterized in that the clean box is installed on an installation space via a support member, so that the clean box is installed on a floor board different from the floor board on which the apparatus body is installed. .

In this inspection apparatus, the clean box is
By being installed in the installation space via the support member, the apparatus is installed on a different floorboard than the floorboard on which the apparatus main body is installed, so that the vibration of the clean box is caused by the floorboard on which the cleanbox is installed. It is cut off from the floor plate on which the apparatus main body is installed, and the transmission of the vibration of the clean box to the apparatus main body is effectively suppressed. Therefore, according to this inspection apparatus, the inspection of the inspection object by the apparatus main body can be appropriately performed.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

First, prior to a specific description of an inspection apparatus to which the present invention is applied, an installation space in which the inspection apparatus is installed will be described.

As shown in FIGS. 1 and 2, an installation space 100 in which an inspection apparatus to which the present invention is applied is composed of a plurality of floor boards 101 made of, for example, a concrete base 10.
2 is spread over. The floor board 101 is, for example,
A material such as aluminum is formed by die-casting into a rectangular plate having a length and width of about 600 mm and a thickness of about 50 mm. This floor board material 10
1 is provided with a large number of ventilation holes 110 penetrating in the thickness direction thereof, and air from an inspection device installed in the installation space 100 is supplied from the ventilation holes 110 to the floor board material 1.
01 and can be discharged to the outside of the installation space 100.

The floor board 101 as described above has a support base 1 of a foundation 102 whose ends are vertically and horizontally laid in a grid pattern.
02a is mounted on the support 02a via the vibration isolating member 103. A plurality of floorboards 101 are vertically and horizontally adjacent to each other on a foundation 102 with a slight gap, so that an installation space 1 in which an inspection apparatus is installed is provided.
00 is configured. The vibration isolating members 103 are for preventing the vibration generated in the floor plate material 101 from being transmitted to the adjacent floor plate material 101, and are disposed at positions where the corners of each floor plate material 101 abut. I have. FIG.
FIG. 2 is a perspective view of the vicinity of a portion where the inspection device is installed in the installation space 100 as viewed obliquely from above, and FIG. 2 is a cross-sectional view taken along line A1-A2 in FIG.

FIG. 3 shows the appearance of an inspection apparatus to which the present invention is applied, which is installed in the installation space 100 as described above. The inspection apparatus 1 is for inspecting a semiconductor wafer on which a predetermined device pattern is formed. When a defect is found in a device pattern formed on the semiconductor wafer, the inspection apparatus 1 determines what the defect is. It examines and classifies.

As shown in FIG. 3, the inspection apparatus 1 includes a clean unit 2 for keeping an environment for inspecting a semiconductor wafer clean. The clean unit 2 includes a clean box 3 formed by bending a stainless steel plate or the like to form a hollow box, and a clean air unit 4 integrally provided above the clean box 3.

The clean box 3 is provided with a window 3a at a predetermined location so that an inspector can visually recognize the inside of the clean box 3 from the window 3a.

The clean air unit 4 is for supplying clean air into the clean box 3, and has two blowers 5a and 5b respectively disposed at different positions on the upper portion of the clean box 3, and these blowers 5a, 5
b and an air filter (not shown) disposed between the clean box 3. The air filter is, for example, a HEPA filter (High Efficiency Particulate).
Air Filter) and ULPA Filter (Ultra Low Penetrat)
ion Air Filter). The clean air unit 4 is provided with blowers 5a, 5b
The dust and the like in the air blown by the above are removed by a high-performance air filter and supplied as clean air into the clean box 3.

In the inspection apparatus 1, the air flow in the clean box 3 is controlled by individually controlling the amount of clean air supplied from the clean air unit 4 into the clean box 3 for each of the two blowers 5a and 5b. Has been made to be able to control appropriately. Here, an example in which the clean air unit 4 includes two blowers 5a and 5b will be described. However, the number of blowers may be determined according to the size and shape of the clean box 3, and three or more blowers are provided. It may be configured. In this case, the amount of clean air supplied from the clean air unit 4 into the clean box 3 is individually controlled for each blower.

The clean box 3 in which the clean air unit 4 is integrally provided at the upper part is installed in the installation space 100 with the leg 6 provided at the lower end thereof being mounted on the support member 70. . The lower end of the clean box 3 facing the installation space 100 is in an open state, and the air supplied into the clean box 3 from the clean air unit 4 mainly flows from the lower end of the clean box 3. Floor board material 101 discharged outside the clean box 3 and constituting the installation space 100
Installation space 1 through a ventilation hole 101a provided in
00 is discharged below. An opening area is provided at a predetermined position on the side surface of the clean box 3, and air supplied from the clean air unit 4 into the clean box 3 is provided on the side surface of the clean box 3. The air is also discharged from the open area to the outside of the clean box 3.

The clean unit 2 always supplies clean air from the clean air unit 4 to the clean box 3 as described above, and circulates air circulated in the clean box 3 as an air flow to the outside of the clean box 3. To be discharged. As a result, dust and the like generated in the clean box 3 are discharged to the outside of the clean box 3 together with the air, so that the internal environment of the clean box 3 is maintained at a very high degree of cleanness, for example, about class 1. .

The support member 70 on which the legs 6 of the clean box 3 are placed is different from the floor plate 101 on which the apparatus body 10 described later is installed, among a plurality of floor boards 101 constituting the installation space 100. This is for installing the clean box 3 on different floor boards 101. Here, among the plurality of floorboards 101 constituting the installation space 100, as the floorboard 101 on which the apparatus main body 100 is installed, for example, a floorboard 101a called an anti-vibration gantry is used, and other parts are used. Uses a floor plate material 101b called grating. The anti-vibration pedestal 101a is a floor plate material having more excellent load resistance and vibration resistance than the grating 101b.

The supporting member 70 is formed by bending a metal plate or the like having a predetermined thickness, and
And a supporting leg 72 extending downward from both ends of the mounting portion 71. The support member 70 supports the anti-vibration gantry 101a on which the apparatus main body 10 is installed among the plurality of floor plate members 101 constituting the installation space 100, and supports the support leg 70 on a grating 101b disposed outside the anti-vibration mount 101a. It is arranged in the installation space 100 so that 72 is located.
The installation section 7 of the support member 70 thus arranged
By mounting the leg 6 of the clean box 3 on 1, the clean box 3 is installed on the grating 101b disposed outside the anti-vibration gantry 101a on which the apparatus main body 10 is installed. Become.

In the inspection apparatus 1 to which the present invention is applied, as described above, the clean box 3 is installed on the floor board 101 different from the floor board 101 on which the apparatus body 10 is installed via the support member 70. Accordingly, the transmission of the vibration generated in the clean box 3 to the apparatus main body 10 via the floor plate 101 is suppressed.

That is, since the clean box 3 is integrally provided with a clean air unit 4 for supplying clean air into the clean box 3 above the blower 5a, 5b of the clean air unit 4. In many cases, the vibration generated by the operation described above is transmitted to the clean box 3, and the clean box 3 is often vibrated. In addition, even when the inspector touches the clean box 3, the clean box 3 may be vibrated. When the vibration occurs in the clean box 3 as described above, the clean box 3 and the apparatus main body 10 have the same floor plate material 101.
If installed on the upper side, the vibration generated in the clean box 3 may be transmitted to the apparatus main body 10 via the floor plate 101, and an appropriate inspection by the apparatus main body 10 may be hindered.
In particular, in the inspection apparatus 1, as will be described in detail later, a fine pattern is inspected at a high resolution using ultraviolet light. It may be. Therefore, in the inspection apparatus 1, by using the support member 70, the clean box 3 is installed on the floor board 101 different from the floor board 101 on which the apparatus main body 10 is installed, and the vibration generated in the clean box 3 is provided. Is not transmitted to the apparatus main body 10.

As a method of installing the clean box 3 on a floor board 101 different from the floor board 101 on which the apparatus body 10 is installed, it is necessary to make the size of the clean box 3 sufficiently larger than the size of the apparatus body 10. It is conceivable that if the size of the clean box 3 is too large, it is necessary to increase the number of blowers or to install an air filter in a wide area in order to maintain the cleanness of the internal environment, thereby increasing costs. In addition, it becomes difficult to appropriately control the airflow in the clean box 3, and it may not be possible to properly discharge dust and the like generated in the clean box 3 to the outside of the clean box 3. If the size of the clean box 3 is too large, the installation space 100 needs to be increased accordingly, which is disadvantageous in saving space.

On the other hand, the clean box 3 is supported by the support member 70 disposed on the floor board 101 different from the floor board 101 on which the apparatus body 10 is installed, so that the clean box 3 is If the clean box 3 is installed on a floor board 101 different from the floor board 101 to be installed, it is not necessary to increase the size of the clean box 3, thereby increasing the cost and controlling the airflow in the clean box 3. The transmission of the vibration generated in the clean box 3 to the apparatus main body 10 can be effectively suppressed without causing the inconvenience that the cleaning becomes difficult. When the clean box 3 is installed on the floor board 101 different from the floor board 101 on which the apparatus body 10 is installed using the support member 70, the entire inspection apparatus 1 is compact. This is very advantageous in saving space.

In the above, an example in which the leg 6 of the clean box 3 is mounted on the mounting portion 71 of the support member 70 so that the clean box 3 is supported by the support member 70 will be described. However, in the inspection device 1 according to the present invention, the support member 70 may directly support the lower end of the clean box 3 without providing the leg 6 in the clean box 3. Further, the leg 6 of the clean box 3 and the support member 70 are configured as an integral member, and the leg 6 of the clean box 3 straddles the floor plate 101 on which the apparatus body 10 is installed. May be installed on different floor boards 101.

In this inspection apparatus 1, as shown in FIG.
The apparatus main body 10 is housed inside the clean box 3,
In the clean box 3, an inspection of a semiconductor wafer on which a predetermined device pattern is formed is performed by the apparatus main body 10. Here, the semiconductor wafer to be inspected is placed in a predetermined hermetically sealed container 7 and transported.
It is transported inside. FIG. 4 shows the inside of the clean box 3 viewed from the direction of arrow B in FIG.

The container 7 has a bottom 7a, a cassette 7b fixed to the bottom 7a, and a cover 7c detachably engaged with the bottom 7a to cover the cassette 7b. The semiconductor wafers to be inspected are mounted on the cassette 7b such that a plurality of the semiconductor wafers are overlapped at a predetermined interval, and are sealed by the bottom 7a and the cover 7c.

When inspecting a semiconductor wafer,
First, a container 7 containing a semiconductor wafer is installed in a container installation space 8 provided at a predetermined position of the clean box 3. In the container installation space 8, an upper surface of an elevator 22a of an elevator 22 to be described later is
The container 7 is installed in the container installation space 8 such that the bottom 7a is located on the elevator 22a of the elevator 22.

When the container 7 is set in the container setting space 8, the engagement between the bottom 7a of the container 7 and the cover 7c is released. When the elevator 22a of the elevator 22 is lowered in the direction of arrow B in FIG. 2, the bottom 7a of the container 7 and the cassette 7b are separated from the cover 7c and moved into the clean box 3. Thereby, the semiconductor wafer to be inspected is transferred into the clean box 3 without being exposed to the outside air.

When the semiconductor wafer is transferred into the clean box 3, the semiconductor robot to be inspected is taken out of the cassette 7b and inspected by the transfer robot 23 described later.

As described above, the inspection apparatus 1 performs the inspection of the semiconductor wafer inside the clean box 3 maintained at a high degree of cleanliness. Inconveniences such as obstruction of a simple test can be effectively avoided. In addition, the semiconductor wafer to be inspected is placed in a sealed container 7 and transported, and the semiconductor wafer is transferred into the clean box 3 via the container 7. If only the inside of the container 7 is maintained at a sufficient degree of cleanness, it is possible to effectively prevent dust and the like from adhering to the semiconductor wafer without increasing the cleanliness of the entire environment in which the inspection device 1 is installed. .

By locally increasing only the degree of cleanliness at a necessary place in this way, it is possible to achieve a high degree of cleanliness and significantly reduce the cost for realizing a clean environment. The mechanical interface between the closed container 7 and the clean box 3 is a so-called SMIF (standard mechanical interface).
ace) is preferable, and in that case, a so-called SMIF-POD is used as the closed container 7.

As shown in FIG. 3, the inspection apparatus 1 includes an external unit 50 in which a computer for operating the apparatus main body 10 is disposed. This external unit 50 is installed outside the clean box 3. The external unit 50 includes a display device 51 for displaying an image or the like obtained by imaging a semiconductor wafer, a display device 52 for displaying various conditions at the time of inspection, and a device body 10.
An input device 53 and the like for inputting an instruction and the like are also provided. The inspector who inspects the semiconductor wafer inputs necessary instructions from the input device 53 arranged in the external unit 50 while viewing the display devices 51 and 52 arranged in the external unit 50, and inspects the semiconductor wafer. I do.

The apparatus body 10 disposed inside the clean box 3 has a support 11 as shown in FIG. The support table 11 is a table for supporting each mechanism of the apparatus main body 10. A leg 1 is provided at the bottom of the support base 11.
The support base 11 and each mechanism provided on the support base 11 are separated from the clean box 3 by the legs 12 so as to be independent of the clean box 3.
Is supported on a floor board 101 different from the floor board 101 on which the is installed.

On the support table 11, via a vibration isolation table 13,
An inspection stage 14 on which a semiconductor wafer to be inspected is placed is provided.

The anti-vibration table 13 is for suppressing vibration generated in the apparatus main body 10 such as vibration from the floor and vibration generated when the inspection stage 14 is moved. Stone surface plate 13a to be installed,
It has a plurality of movable legs 13b that support the stone surface plate 13a. The anti-vibration table 13 detects the vibration of the apparatus main body 10 when the vibration is generated, and detects the vibration of the movable leg 13b.
Is driven to quickly cancel the vibration of the stone base 13a and the inspection stage 14 installed on the stone base 13a.

In the inspection apparatus 1, the inspection stage 14 on which the semiconductor wafer to be inspected is installed is provided on the anti-vibration table 13, so that even if the apparatus body 10 is vibrated, This vibration is canceled quickly, the influence of the vibration is suppressed, and the inspection capability at the time of performing inspection with high resolution using ultraviolet light is improved.

The inspection stage 14 is placed on the vibration isolation table 13.
In order to stably install the vibration isolator, it is desirable that the center of gravity of the vibration isolation table 13 is located at a somewhat lower position. Therefore, in this inspection device 1, the notch 13 is formed at the lower end of the stone platen 13a.
c is provided so that the movable leg 13b supports the stone surface plate 13a at the notch 13c, thereby lowering the center of gravity of the vibration isolation table 13.

It should be noted that vibrations or the like generated when the inspection stage 14 is moved can be predicted to some extent in advance. If the vibration isolation table 13 is operated by predicting such vibrations in advance, it is possible to prevent the vibrations occurring on the inspection stage 14 from occurring. Therefore, it is desirable that the inspection apparatus 1 operates the anti-vibration table 13 by predicting in advance vibrations and the like that occur when the inspection stage 14 is moved.

The inspection stage 14 is a stage for supporting a semiconductor wafer to be inspected. The inspection stage 14 has a function of supporting a semiconductor wafer to be inspected and a function of moving the semiconductor wafer to a predetermined inspection target position.

Specifically, the inspection stage 14 includes an X stage 15 installed on the vibration isolation table 13 and an X stage 1
5, a Y stage 16 installed on the Y stage 16, a θ stage 17 installed on the Y stage 16, a Z stage 18 installed on the θ stage 17, and a suction plate 19 installed on the Z stage 18. Have.

The X stage 15 and the Y stage 16 are stages that move in the horizontal direction.
The stage 16 moves semiconductor wafers to be inspected in directions orthogonal to each other, and guides a device pattern to be inspected to a predetermined inspection position.

The .theta. Stage 17 is a so-called rotary stage for rotating a semiconductor wafer.
When inspecting the semiconductor wafer, the semiconductor wafer is rotated by the θ stage 17 so that, for example, the device pattern on the semiconductor wafer is horizontal or vertical to the screen.

The Z stage 18 is a stage that moves in the vertical direction and adjusts the height of the stage. When inspecting a semiconductor wafer, the Z stage 18 is used to adjust the inspection surface of the semiconductor wafer to an appropriate height.
Adjust the height of the stage.

The suction plate 19 is for sucking and fixing the semiconductor wafer to be inspected. During the inspection of the semiconductor wafer, the semiconductor wafer to be inspected is placed on the suction plate 19 and is sucked by the suction plate 18 to suppress unnecessary movement.

An optical unit 21 supported by a frame 20 is disposed on the vibration isolation table 12 so as to be positioned on the inspection stage 14. The optical unit 21 is for taking an image of a semiconductor wafer when inspecting the semiconductor wafer. The optical unit 21 has a function of capturing an image of a semiconductor wafer to be inspected at low resolution using visible light, and a function of capturing an image of a semiconductor wafer to be inspected at high resolution using ultraviolet light. It also has the function to perform.

As shown in FIGS. 4 and 5, an elevator 22 for taking out a cassette 7b on which a semiconductor wafer to be inspected is mounted from the container 7 and moving the cassette 7b into the clean box 3, as shown in FIGS. Is provided. Further, as shown in FIG. 5, a transfer robot 23 for transferring the semiconductor wafer, and centering and phase setting of the semiconductor wafer before placing the semiconductor wafer on the inspection stage 14 are provided on the support base 11, as shown in FIG. Is provided. FIG. 5 is a plan view schematically showing the apparatus main body 10 viewed from above.

The elevator 22 has an elevating platform 22 a which can be raised and lowered. The container 7 is installed in the container installation space 8 of the clean box 3 and the bottom 7
a when the engagement between the cover a and the cover 7c is released.
The lower portion 2a is operated to lower the bottom portion 7a of the container 7.
Then, the cassette 7b fixed thereto is moved into the clean box 3.

The transfer robot 23 has an operation arm 23b provided with a suction mechanism 23a at the distal end thereof. The operation arm 23b is moved and the semiconductor arm is moved by the suction mechanism 23a provided at the distal end. The wafer is sucked, and the semiconductor wafer is transported in the clean box 3.

The pre-aligner 24 carries out phase setting and center setting of the semiconductor wafer with reference to an orientation flat and a notch formed in advance on the semiconductor wafer. The inspection apparatus 1 sets the pre-aligner 24 before placing the semiconductor wafer on the inspection stage 14.
In this way, the efficiency of the inspection is improved by performing the phase setting or the like.

When the semiconductor wafer is set on the inspection stage 14, first, the bottom 7 a of the container 7 and the cassette 7 b are moved into the clean box 3 by the elevator 22. Then, a semiconductor wafer to be inspected is selected from the plurality of semiconductor wafers mounted on the cassette 7b, and the selected semiconductor wafer is taken out of the cassette 7b by the transfer robot 23.

The semiconductor wafer taken out of the cassette 7b is transferred to the pre-aligner 24 by the transfer robot 23. The semiconductor wafer conveyed to the pre-aligner 24 is subjected to phase setting and center setting by the pre-aligner 24. Then, the semiconductor wafer on which the phase setting and the center setting have been performed is transferred to the inspection stage 14 by the transfer robot 23, and is placed on the suction plate 19 to perform the inspection.

When the semiconductor wafer to be inspected is transported to the inspection stage 14, the semiconductor wafer to be inspected next is taken out of the cassette 7b by the transport robot 23 and transported to the pre-aligner 24. Then, while the inspection of the semiconductor wafer previously conveyed to the inspection stage 14 is being performed, the phase of the semiconductor wafer to be inspected next and the centering are performed. When the inspection of the semiconductor wafer previously transported to the inspection stage 14 is completed, the next semiconductor wafer to be inspected is immediately transported to the inspection stage 14.

As described above, before the semiconductor wafer to be inspected is conveyed to the inspection stage 14, the inspection apparatus 1 performs the phase alignment and the center alignment by the pre-aligner 24, so that the inspection stage 14 The time required for positioning the semiconductor wafer can be reduced. Further, the inspection apparatus 1 takes out the semiconductor wafer to be inspected next from the cassette 7b by using the time during which the inspection of the semiconductor wafer previously carried to the inspection stage 14 is being performed, and performs phase detection by the pre-aligner 24. By performing the centering and the centering, the overall time can be reduced, and the inspection can be performed efficiently.

In the inspection apparatus 1, the elevator 22, the transfer robot 23, the pre-aligner 2
4 are installed on the support base 11 so as to be lined up in a straight line as shown in FIG. The respective installation positions are determined so that the distance L1 between the elevator 22 and the transfer robot 23 is substantially equal to the distance L2 between the transfer robot 23 and the pre-aligner 24. Further, from the viewpoint of the transfer robot 23,
The inspection stage 14 is arranged in a direction substantially orthogonal to the direction in which the elevators 22 and the pre-aligners 24 are arranged.

The inspection apparatus 1 can quickly and accurately transport a semiconductor wafer, which is an object to be inspected, by arranging each mechanism as described above.

That is, in the inspection apparatus 1, since the distance L1 between the elevator 22 and the transfer robot 23 is substantially equal to the distance L2 between the transfer robot 23 and the pre-aligner 24, Transfer robot 23
Without changing the length of the arm 23b of the cassette 7b.
The semiconductor wafer taken out of the wafer can be transferred to the pre-aligner 24. Therefore, in the inspection apparatus 1, since an error or the like generated when the length of the arm 23b of the transfer robot 23 is changed does not matter, the operation of transferring the semiconductor wafer to the pre-aligner 24 can be performed accurately. Further, since the elevator 22, the transfer robot 23, and the pre-aligner 24 are arranged in a straight line, the transfer robot 23 can transfer the semiconductor wafer taken out of the cassette 7b to the pre-aligner 24 only by linear movement. . Therefore, in the inspection apparatus 1, the operation of transporting the semiconductor wafer to the pre-aligner 24 can be performed extremely accurately and quickly.

Further, in the inspection apparatus 1, as viewed from the transfer robot 23, the elevator 22 and the pre-aligner 24
Are arranged so that the inspection stage 14 is positioned in a direction substantially perpendicular to the direction in which the semiconductor wafers are arranged, so that the semiconductor wafer is transported to the inspection stage 14 by the linear movement of the transport robot 23. be able to. Therefore,
In this inspection apparatus 1, a semiconductor wafer is placed on an inspection stage 1
4 can be performed very accurately and quickly. In particular, the inspection apparatus 1 inspects a semiconductor wafer on which a fine device pattern is formed.
Since the transfer and positioning of the semiconductor wafer to be inspected must be performed very accurately, the above arrangement is very effective.

Next, the inspection apparatus 1 will be described in more detail with reference to the block diagram of FIG.

As shown in FIG. 6, an external unit 50 of the inspection apparatus 1 has an image processing computer 60 to which a display device 51 and an input device 53a are connected, and a control device to which a display device 52 and an input device 53b are connected. Computer 61
And are arranged. In FIG. 1, the input device 53a connected to the image processing computer 60 and the input device 53b connected to the control computer 61 are collectively shown as the input device 53.

When inspecting a semiconductor wafer, the computer for image processing 60 operates the CCD (charge-coupled device) camera 30 installed inside the optical unit 21.
A computer that takes in and processes an image obtained by imaging a semiconductor wafer by 31. That is, this inspection device 1
Performs inspection of the semiconductor wafer by processing and analyzing the image of the semiconductor wafer captured by the CCD cameras 30 and 31 installed inside the optical unit 21 by the image processing computer 60.

The input device 53a connected to the image processing computer 60 is used to input, to the image processing computer 30, instructions necessary for analyzing images captured from the CCD cameras 30, 31. And comprises, for example, a pointing device such as a mouse, a keyboard, and the like. The display device 51 connected to the image processing computer 60 is for displaying analysis results of images taken from the CCD cameras 30 and 31, and is composed of, for example, a CRT display or a liquid crystal display.

When inspecting a semiconductor wafer, the control computer 61 controls the inspection stage 14, the elevator 2
2. A computer for controlling the transfer robot 23, the pre-aligner 24, and each device inside the optical unit 12. That is, the inspection apparatus 1 controls the control computer so that an image of the semiconductor wafer to be inspected is picked up by the CCD cameras 30 and 31 installed inside the optical unit 21 when inspecting the semiconductor wafer. 61, the inspection stage 14, the elevator 2
2. It controls the transfer robot 23, the pre-aligner 24, and each device inside the optical unit 21.

The control computer 61 has a function of controlling the blowers 5a and 5b of the clean air unit 4. That is, the inspection apparatus 1 controls the blowers 5 a and 5 b of the clean air unit 4
Is controlled to constantly supply clean air into the clean box 3 when inspecting a semiconductor wafer,
Further, the air flow in the clean box 3 can be controlled.

The input device 53 b connected to the control computer 61 includes the inspection stage 14, the elevator 22, the transfer robot 23 and the pre-aligner 24, each device inside the optical unit 21, and the blower of the clean air unit 4. This is for inputting an instruction necessary for controlling 5a, 5b and the like to the control computer 61, and includes, for example, a pointing device such as a mouse or a keyboard. The control computer 6
1 is for displaying various conditions and the like at the time of inspection of a semiconductor wafer.
It consists of an RT display, a liquid crystal display and the like.

The image processing computer 60 and the control computer 61 can exchange data with each other by a memory link mechanism. That is,
Image processing computer 60 and control computer 61
Are connected to each other via memory link interfaces 60a and 61a provided respectively, so that the image processing computer 60 and the control computer 51 can exchange data with each other.

On the other hand, inside the clean box 3 of the inspection apparatus 1, the semiconductor wafer placed in the closed container 7 and conveyed is taken out from the cassette 7 b of the container 7 and set on the inspection stage 14. As described above, the elevator 22, the transfer robot 23, and the pre-aligner 24 are arranged as mechanisms. These are connected to a control computer 61 arranged in the external unit 50 via a robot control interface 61b.
Then, control signals are sent from the control computer 61 to the elevator 22, the transfer robot 23, and the pre-aligner 24 via the robot control interface 61b.

That is, the semiconductor wafers conveyed in the closed container 7 are transferred to the cassette 7 of the container 7.
b, when it is taken out and installed on the inspection stage 14,
Control signals are sent from the control computer 61 to the elevator 22, the transfer robot 23, and the pre-aligner 24 via the robot control interface 61b. Then, the elevator 22, the transfer robot 23, and the pre-aligner 24 operate based on the control signal, and as described above, the semiconductor wafers that have been transported in the closed container 7 are transferred to the cassette 7b of the container 7. , And the phase and center are set by the pre-aligner 25 and set on the inspection stage 14.

Further, a vibration isolation table 13 is disposed inside the clean box 3 of the inspection apparatus 1, and the X stage 15 and the Y stage 1 are mounted on the vibration isolation table 13 as described above.
6, an inspection stage 14 including a θ stage 17, a Z stage 18, and a suction plate 19 is provided.

Here, the X stage 15 and the Y stage 1
6, the θ stage 17, the Z stage 18, and the suction plate 19 are connected to a control computer 61 arranged in the external unit 50 via a stage control interface 61c. Then, control signals are sent from the control computer 61 to the X stage 15, the Y stage 16, the θ stage 17, the Z stage 18, and the suction plate 19 via the stage control interface 61c.

That is, when inspecting a semiconductor wafer, control signals are sent from the control computer 61 to the X stage 15, Y stage 16, θ stage 17, Z stage 18 and suction plate 19 via the stage control interface 61c. Sent out. And X stage 1
5, Y stage 16, θ stage 17, Z stage 18
The suction plate 19 operates on the basis of the control signal to suck and fix the semiconductor wafer to be inspected by the suction plate 19, and the semiconductor stage is controlled by the X stage 15, the Y stage 16, the θ stage 17 and the Z stage 18. The wafer is moved to a predetermined position, angle and height.

As described above, the optical unit 21 is also provided on the vibration isolation table 12. The optical unit 21 is for taking an image of the semiconductor wafer at the time of inspecting the semiconductor wafer, and as described above, the function of taking an image of the semiconductor wafer to be inspected at a low resolution using visible light. And a function of capturing an image of a semiconductor wafer to be inspected with high resolution using ultraviolet light.

Inside the optical unit 21, there is provided a mechanism for capturing an image of a semiconductor wafer with visible light.
A CCD camera 30 for visible light, a halogen lamp 32,
An optical system 33 for visible light, an objective lens 34 for visible light, and an autofocus controller 35 for visible light are arranged.

When the image of the semiconductor wafer is taken with visible light, the halogen lamp 32 is turned on. Here, the driving source of the halogen lamp 32 is the external unit 50.
Is connected via a light source control interface 61d to a control computer 61 arranged in the computer. The driving source of the halogen lamp 32 includes the control computer 6.
1 transmits a control signal via the light source control interface 61d. The turning on / off of the halogen lamp 32 is performed based on this control signal.

When taking an image of a semiconductor wafer with visible light, the halogen lamp 32 is turned on, and the visible light from the halogen lamp 32 is transmitted to the visible light optical system 33.
Then, the semiconductor wafer is illuminated by being applied to the semiconductor wafer via the visible light objective lens 34. Then, the image of the semiconductor wafer illuminated by the visible light is converted into a visible light objective lens 34.
And enlarges the enlarged image with the visible light CCD camera 30.
To capture an image.

Here, the visible light CCD camera 30 is connected to an image processing computer 60 provided in the external unit 50.
Are connected via an image capture interface 60b. Then, the image of the semiconductor wafer captured by the visible light CCD camera 30 is captured by the image processing computer 60 via the image capturing interface 60b.

When an image of a semiconductor wafer is captured with visible light as described above, the visible light autofocus controller 35 performs automatic focus position adjustment. That is, the visible light autofocus control unit 35 detects whether or not the distance between the visible light objective lens 34 and the semiconductor wafer matches the focal length of the visible light objective lens 34. Is a visible light objective lens 34
Alternatively, the Z stage 18 is moved so that the inspection target surface of the semiconductor wafer coincides with the focal plane of the visible light objective lens 34.

Here, the visible light auto-focus control unit 35 sends an auto-focus control interface 61 to a control computer 61 arranged in the external unit 50.
e. Then, a control signal is sent from the control computer 61 to the visible light autofocus control unit 35 via the autofocus control interface 61e. Automatic focus positioning of the visible light objective lens 34 by the visible light autofocus controller 35 is performed based on this control signal.

The optical unit 21 includes a CCD camera 31 for ultraviolet light and a laser light source 3 for ultraviolet light as a mechanism for capturing an image of a semiconductor wafer with ultraviolet light.
6, an optical system 37 for ultraviolet light, and an objective lens 38 for ultraviolet light
And an ultraviolet light autofocus control section 39.

When an image of a semiconductor wafer is taken with ultraviolet light, the ultraviolet laser light source 36 is turned on. Here, the drive source of the ultraviolet laser light source 36 is connected to a control computer 61 arranged in the external unit 50 via a light source control interface 61d. A control signal is sent from the control computer 61 to the drive source of the ultraviolet laser light source 36 via the light source control interface 61d. Turning on / off the ultraviolet laser light source 36
The light is turned off based on this control signal.

It is preferable that the ultraviolet laser light source 36 emits an ultraviolet laser having a wavelength of about 266 nm. An ultraviolet light laser having a wavelength of about 266 nm is obtained as a fourth harmonic of a YAG laser. Further, a laser light source having an oscillation wavelength of about 166 nm has been developed, and such a laser light source may be used as the ultraviolet laser light source.

When capturing an image of a semiconductor wafer with ultraviolet light, the ultraviolet laser light source 36 is turned on, and the ultraviolet light from the ultraviolet laser light source 36 is transmitted to the ultraviolet optical system 37 and the objective lens for ultraviolet light. The semiconductor wafer is illuminated by being applied to the semiconductor wafer via 38. Then, the image of the semiconductor wafer illuminated by the ultraviolet light is enlarged by the ultraviolet light objective lens 38, and the enlarged image is captured by the ultraviolet light CCD camera 31.

Here, the ultraviolet CCD camera 31 is connected to the image processing computer 60 provided in the external unit 50.
Are connected via an image capture interface 60c. The image of the semiconductor wafer captured by the ultraviolet light CCD camera 31 is captured by the image processing computer 60 via the image capturing interface 60c.

When an image of a semiconductor wafer is picked up by ultraviolet light as described above, the automatic focus position is adjusted by the ultraviolet light autofocus control section 39. That is, the autofocus controller 39 for ultraviolet light detects whether or not the interval between the objective lens 38 for ultraviolet light and the semiconductor wafer matches the focal length of the objective lens 38 for ultraviolet light. Is the objective lens 38 for ultraviolet light.
Alternatively, the Z stage 18 is moved so that the inspection surface of the semiconductor wafer coincides with the focal plane of the ultraviolet light objective lens 38.

Here, the auto-focus control section 39 for ultraviolet light is provided to the control computer 61 provided in the external unit 50 by the auto-focus control interface 61.
e. Then, a control signal is sent from the control computer 61 to the ultraviolet light autofocus control section 39 via the autofocus control interface 61e. Automatic focusing of the ultraviolet light objective lens 38 by the ultraviolet light autofocus control unit 39 is performed based on this control signal.

Further, the clean air unit 4 is provided with two blowers 5a and 5b as described above. These blowers 5a and 5b are connected to a control computer 61 arranged in the external unit 50 via an air volume control interface 61f. A control signal is sent from the control computer 61 to the blowers 5a and 5b of the clean air unit 4 via the air volume control interface 61f. Control of the number of rotations of the blowers 5a and 5b, switching on / off, and the like are performed based on this control signal.

Next, the optical unit 21 of the inspection apparatus 1
Will be described in more detail with reference to FIG. Here, the auto focus control units 35 and 3
The description of 9 will be omitted, and an optical system for illuminating the semiconductor wafer to be inspected and an optical system for imaging the semiconductor wafer to be inspected will be described.

As shown in FIG. 7, the optical unit 21
As an optical system for capturing an image of a semiconductor wafer with visible light, a halogen lamp 32 and an optical system 33 for visible light are used.
And a visible light objective lens 34.

The visible light from the halogen lamp 32 is guided to the visible light optical system 33 by the optical fiber 40.
The visible light guided to the visible light optical system 33 first passes through the two lenses 41 and 42 and enters the half mirror 43. Then, the visible light incident on the half mirror 43 is
The light is reflected by the half mirror 43 toward the objective lens 34 for visible light, and enters the semiconductor wafer via the objective lens 34 for visible light. Thereby, the semiconductor wafer is illuminated with the visible light.

Then, the image of the semiconductor wafer illuminated by the visible light is magnified by the visible light objective lens 34,
The light passes through the half mirror 43 and the imaging lens 44 and is imaged by the visible light CCD camera 30. That is,
The reflected light from the semiconductor wafer illuminated by visible light
The light enters the visible light CCD camera 30 via the visible light objective lens 34, the half mirror 43, and the imaging lens 44.
The image is taken by the D camera 30. And C for visible light
An image of the semiconductor wafer (hereinafter, referred to as a visible image) captured by the CD camera 30 is sent to the image processing computer 60.

The optical unit 21 includes an ultraviolet laser light source 36, an ultraviolet optical system 37, and an ultraviolet objective lens 38 as an optical system for capturing an image of a semiconductor wafer with ultraviolet light. Have.

Ultraviolet light from the ultraviolet laser light source 36 is guided to the ultraviolet light optical system 37 by the optical fiber 45.
The ultraviolet light guided to the ultraviolet light optical system 37 first passes through the two lenses 46 and 47 and enters the half mirror 48. Then, the visible light incident on the half mirror 48 is
The light is reflected by the half mirror 48 toward the ultraviolet light objective lens 38 and is incident on the semiconductor wafer via the ultraviolet light objective lens 38. Thereby, the semiconductor wafer is illuminated by the ultraviolet light.

The image of the semiconductor wafer illuminated with the ultraviolet light is enlarged by the ultraviolet light objective lens 38,
The light passes through the half mirror 48 and the imaging lens 49 and is imaged by the ultraviolet light CCD camera 31. That is,
The reflected light from the semiconductor wafer illuminated by ultraviolet light,
The light enters the ultraviolet light CCD camera 31 via the ultraviolet light objective lens 38, the half mirror 48, and the imaging lens 49, whereby the enlarged image of the semiconductor wafer is converted to the ultraviolet light CC.
The image is captured by the D camera 31. And UV light C
The image of the semiconductor wafer (hereinafter, referred to as an ultraviolet image) captured by the CD camera 31 is sent to the image processing computer 60.

In the inspection apparatus 1 described above, an image of a semiconductor wafer can be imaged and inspected by ultraviolet light having a wavelength shorter than that of visible light. As compared with the case of performing classification, finer defects can be detected and classified.

In addition, the inspection apparatus 1 has both an optical system for visible light and an optical system for ultraviolet light, and inspects a semiconductor wafer at a low resolution using visible light and uses an ultraviolet light. Inspection of a semiconductor wafer with high resolution can be performed. Therefore, the inspection apparatus 1 detects and classifies large defects by inspecting a semiconductor wafer at low resolution using visible light, and inspects a semiconductor wafer at high resolution using ultraviolet light. It is also possible to detect and classify small defects.

In the inspection apparatus 1, the numerical aperture NA of the ultraviolet light objective lens 40 is preferably large.
For example, it is set to 0.9 or more. As described above, by using a lens having a large numerical aperture NA as the ultraviolet light objective lens 40, it is possible to detect a finer defect.

When a defect of a semiconductor wafer is composed of only irregularities without color information, such as a scratch, the defect can hardly be seen with light having no coherence. On the other hand, when light having excellent coherence, such as laser light, is used, even when a defect such as a scratch has no color information and consists only of irregularities, light is generated in the vicinity of the irregularities. By interfering, the defect can be clearly seen. The inspection apparatus 1 uses an ultraviolet laser light source 36 that emits laser light in the ultraviolet region as a light source of ultraviolet light. Therefore, in the above inspection device 1,
Even a defect such as a scratch, which has no color information and consists only of irregularities, can be clearly detected. That is, in the inspection apparatus 1, the halogen lamp 3
Phase information, which is difficult to detect with visible light (incoherent light) from 2, can be easily detected using the ultraviolet laser (coherent light) from the ultraviolet laser light source 36.

Next, an example of a procedure for inspecting a semiconductor wafer by the inspection apparatus 1 will be described with reference to a flowchart of FIG. Note that the flowchart of FIG. 8 illustrates a procedure of a process after a state where the semiconductor wafer to be inspected is set on the inspection stage 14. Further, the flowchart shown in FIG. 8 shows an example of a procedure when the defect is inspected by the inspection apparatus 1 and classified when the position of the defect on the semiconductor wafer is known in advance. Here, it is assumed that a number of similar device patterns are formed on a semiconductor wafer, and the detection and classification of defects are performed by using an image of a defective area (a defect image) and an image of another area (a reference image). ) Is taken and compared.

First, as shown in step S1-1, a defect position coordinate file is read into the control computer 61. Here, the defect position coordinate file is a file in which information relating to the position of the defect on the semiconductor wafer is described, and is created by measuring the position of the defect on the semiconductor wafer in advance by a defect detection device or the like. Then, here, the defect position coordinate file is read into the control computer 61.

Next, in step S1-2, the X stage 15 and the Y stage 16 are driven by the control computer 61 to move the semiconductor wafer to the defect position coordinates indicated by the defect position coordinate file. In the field of view of the objective lens 34 for visible light.

Next, in step S1-3, the visible light autofocus controller 35 is driven by the control computer 61 to perform automatic focus positioning of the visible light objective lens.

Next, in step S1-4, an image of the semiconductor wafer is captured by the visible light CCD camera 30, and the captured visible image is sent to the image processing computer 60. The visible image captured here is an image at the defect position coordinates indicated by the defect position coordinate file, that is, an image of a region where a defect is present (hereinafter, referred to as a defect image).

Next, at step S1-5, the X stage 15 and the Y stage 16 are driven by the control computer 61 to move the semiconductor wafer to the reference position coordinates, and the reference area of the semiconductor wafer is changed to the visible light objective lens. 3
4 so that it is within the field of view. Here, the reference region is a region other than the inspection target region of the semiconductor wafer, and is a region where a device pattern similar to the device pattern in the inspection target region of the semiconductor wafer is formed.

Next, in step S1-6, the visible light autofocus controller 35 is driven by the control computer 61 to perform automatic focusing of the visible light objective lens.

Next, in step S1-7, an image of the semiconductor wafer is captured by the visible light CCD camera 30, and the captured visible image is sent to the image processing computer 60. Note that the visible image captured here is an image of a region where a device pattern similar to the device pattern in the inspection target region of the semiconductor wafer is formed (hereinafter, referred to as a reference image).

Next, in step S1-8, the image processing computer 60 compares the defect image captured in step S1-4 with the reference image captured in step S1-7, and detects a defect from the defect image. I do. If a defect is detected, the process proceeds to step S1-9. If a defect is not detected, the process proceeds to step S1-9.
Proceed to 11.

In step S1-9, the image processing computer 60 checks what the detected defect is and classifies it. If the defect can be classified, the process proceeds to step S1-10. If the defect cannot be classified, the process proceeds to step S1-11.

In step S1-10, the result of defect classification is stored. Here, the defect classification result is stored in, for example, a storage device connected to the image processing computer 60 or the control computer 61. Note that the defect classification result may be transferred to another computer connected to the image processing computer 60 or the control computer 61 via a network, and may be stored.

When the processing in step S1-10 is completed, the classification of the defects in the semiconductor wafer has been completed, and the processing is ended here. However, when there are a plurality of defects on the semiconductor wafer, the process may return to step S1-2 to detect and classify other defects.

On the other hand, if the defect cannot be detected in step S1-8, or if the defect cannot be classified in step S1-9, the process proceeds to step S1-11 and the subsequent steps. Defect detection and classification are performed by imaging at a resolution.

In this case, first, in step S1-11, the X stage 15 is controlled by the control computer 61.
Then, the Y stage 16 is driven to move the semiconductor wafer to the defect position coordinates indicated by the defect position coordinate file, so that the inspection target area of the semiconductor wafer falls within the field of view of the ultraviolet light objective lens 38.

Next, in step S1-12, the control computer 61 drives the ultraviolet auto focus control unit 39 to perform automatic focus positioning of the ultraviolet light objective lens.

Next, in step S1-13, an image of the semiconductor wafer is captured by the ultraviolet CCD camera 31, and the captured ultraviolet image is sent to the image processing computer 60. The ultraviolet image captured here is an image at the defect position coordinates indicated by the defect position coordinate file, that is, a defect image. In addition, imaging of the defect image here is performed with higher resolution than imaging using visible light, using ultraviolet light that is light having a shorter wavelength than visible light.

Next, in step S1-14, the X stage 15 and the Y stage 16 are driven by the control computer 61 to move the semiconductor wafer to the reference position coordinates. 38. Here, the reference area is
This is an area other than the inspection target area of the semiconductor wafer, in which a device pattern similar to the device pattern in the inspection target area of the semiconductor wafer is formed.

Next, in step S1-15, the control computer 61 drives the ultraviolet light autofocus control section 39 to perform automatic focus position adjustment of the ultraviolet light objective lens 38.

Next, in step S1-16, an image of the semiconductor wafer is captured by the ultraviolet CCD camera 31, and the captured ultraviolet image is sent to the image processing computer 60. The ultraviolet image captured here is an image of a region where a device pattern similar to the device pattern in the inspection target region of the semiconductor wafer is formed, that is, a reference image. The imaging of the reference image here is performed at a higher resolution than when visible light is used by using ultraviolet light that is light having a shorter wavelength than visible light.

Next, in step S1-17, the image processing computer 60 compares the defect image captured in step S1-13 with the reference image captured in step S1-16, and detects a defect from the defect image. I do.
If a defect can be detected, step S1-1
Proceeding to step S8, if no defect is detected, proceeding to step S1-19.

In step S1-18, the image processing computer 60 checks what the detected defect is and performs classification. If the defect classification has been completed, the process proceeds to step S1-10, and the defect classification result is stored as described above. On the other hand, if the defect cannot be classified, the process proceeds to step S1-19.

In step S1-19, information indicating that the defect cannot be classified is stored. Here, information indicating that the defect cannot be classified is stored, for example, in a storage device connected to the image processing computer 60 or the control computer 61. Note that this information may be transferred to another computer connected to the image processing computer 60 or the control computer 61 via a network and stored.

According to the above-described procedure, first, the image picked up by the visible light CCD camera 30 is processed and analyzed to inspect the semiconductor wafer at a low resolution, and to detect a defect by visible light. When classification was not possible,
Next, the semiconductor wafer is inspected with high resolution by processing and analyzing the image captured by the ultraviolet CCD camera 31.

Here, a method of detecting a defect from the reference image and the defect image captured by the CCD cameras 30 and 31 will be described with reference to FIG.

FIG. 9A shows an example of an image of a reference region where a device pattern similar to the device pattern in the inspection target region is formed, that is, an example of the reference image. FIG. 9B shows an example of an image of the inspection target area determined to have a defect, that is, a defect image.

When detecting a defect from such a reference image and a defect image, a device pattern is extracted from the reference image as shown in FIG. 9C based on color information, density information, and the like. Further, a difference image is obtained from the reference image and the defect image, and a portion having a large difference is extracted as a defect as shown in FIG.

Then, as shown in FIG.
An image obtained by superimposing the image of the device pattern extraction result shown in FIG. 9C and the image of the defect extraction result shown in FIG. 9D is obtained, and the rate at which the defect exists in the device pattern is determined. It is extracted as a feature value.

By the above-described method, the CCD camera 3
The image processing computer 60 processes and analyzes the reference image and the defect image captured by 0 and 31 to detect a defect and inspect a semiconductor wafer.

As described above, the inspection apparatus 1 first inspects the semiconductor wafer at low resolution by processing and analyzing the image picked up by the visible light CCD camera 30, and inspects the defect by visible light. If the detection and classification cannot be performed, the semiconductor wafer is inspected at a high resolution by processing and analyzing the image captured by the ultraviolet CCD camera 31. It is possible to detect and classify finer defects as compared with the case of detecting and classifying defects using only visible light.

However, when imaging with low resolution using visible light, the area that can be imaged at a time is wider. If the defect is sufficiently large, inspection of the semiconductor wafer with low resolution using visible light is possible. Is more efficient. Therefore,
Rather than using ultraviolet light to inspect and classify defects from the beginning, as described above, inspecting and classifying defects using visible light first enables more efficient semiconductor wafers. Inspection can be performed.

Further, in the inspection apparatus 1, as described above, the clean box 3 is installed in the installation space 100 while being supported by the support member 70, so that a plurality of floor plate members constituting the installation space 100 are provided. 1
In FIG. 1, the clean box 3 is installed on a floor board 101 different from the floor board 101 on which the apparatus body 10 is installed. Therefore, this inspection device 1
Then, the vibration generated in the clean box 3 is
Can be effectively suppressed, and the inspection of a fine pattern of a semiconductor wafer by the apparatus main body 10 can be appropriately performed.

In the above description, the inspection apparatus 1 to which the present invention is applied has been used for checking what the defect is in the semiconductor wafer. However, the use of the inspection apparatus 1 according to the present invention can be used for purposes other than the defect identification of the semiconductor wafer. That is, the inspection apparatus 1 according to the present invention can be used, for example, to inspect whether a device pattern formed on a semiconductor wafer is formed in an appropriate shape as a desired pattern. Further, the use of the inspection device 1 according to the present invention is not limited to inspection of a semiconductor wafer, and the inspection device 1 according to the present invention is widely applicable to inspection of fine patterns. It is also effective for inspection of flat panel displays on which various patterns are formed.

[0134]

As described above in detail, in the inspection apparatus according to the present invention, the clean box in which the apparatus main body is accommodated is installed in the installation space via the support member, so that the apparatus main body is provided. Because it is made to be installed on a floor plate material different from the floor plate material where the part is installed,
The transmission of the vibration of the clean box to the apparatus main body is effectively suppressed. Therefore, according to this inspection device,
The inspection of the inspection object by the apparatus main body can be appropriately performed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state where a part of an installation space in which an inspection apparatus to which the present invention is applied is installed is viewed obliquely from above.

FIG. 2 is a sectional view taken along line A1-A2 in FIG.

FIG. 3 is a perspective view showing an appearance of an inspection apparatus to which the present invention is applied.

FIG. 4 is a diagram showing a state where the apparatus main body disposed inside a clean box of the inspection apparatus is viewed from the direction of arrow B in FIG. 3;

FIG. 5 is a plan view schematically showing a state where the apparatus main body of the inspection apparatus is viewed from above.

FIG. 6 is a block diagram illustrating a configuration example of the inspection device.

FIG. 7 is a diagram showing a configuration example of an optical system of an optical unit of the inspection device.

FIG. 8 is a flowchart illustrating an example of a procedure when a semiconductor wafer is inspected by the inspection apparatus.

FIG. 9 is a diagram for explaining a method of detecting a defect from a reference image and a defect image.

[Explanation of symbols]

1 inspection device, 2 clean unit, 3 clean box, 4 clean air unit, 6 legs, 10
Device body, 12 legs, 14 Inspection stage, 21
Optical unit, 22 elevator, 23 transport robot, 24 pre-aligner, 30 visible light CCD camera, 31 ultraviolet light CCD camera, 32 halogen lamp, 33 visible light optical system, 34 visible light objective lens, 36 ultraviolet laser Light source, 37 UV optical system,
38 Objective lens for ultraviolet light, 50 External unit, 70
Support member, 71 Placement section, 72 Support leg, 100 Installation space, 101 Floor plate material

Continued on the front page F-term (reference) 2F065 AA03 AA14 AA49 BB02 BB27 CC19 DD03 DD04 EE06 FF10 FF51 GG02 GG04 GG21 HH03 HH13 JJ03 JJ09 JJ26 LL02 LL04 MM00 MM03 MM04 PP12 QQ24 QQ25 Q01 U02 AQ01 U02 A BA05 BA10 BA20 CB01 CB02 DA03 DA08 DA17 EA08 EA11 EB09 EC01 4M106 AA01 BA05 BA07 CA41 DB04 DB07 DB08 DB30 DJ02 DJ04 DJ05 DJ06 DJ07 DJ11 DJ23

Claims (2)

[Claims] An inspection apparatus installed in an installation space in which a plurality of floorboards are laid, a clean box in which an internal environment is kept clean, and a clean box housed in the clean box, An apparatus main body for inspecting an inspection object, and a support member for supporting the clean box, wherein the clean box is installed in the installation space via the support member, whereby the apparatus main body is installed. An inspection apparatus characterized by being installed on a floor plate different from a floor plate to be processed. 2. The apparatus according to claim 1, wherein the apparatus main body includes an inspection unit that irradiates the inspection object with ultraviolet light and detects reflected light or transmitted light to inspect the inspection object. The inspection device according to claim 1, wherein