JPS6269152A - Inspecting device for foreign matter - Google Patents

Abstract

PURPOSE:To shorten an inspection time even in case the aperture of a slit is made small enough, by reflecting passing rays of light of plural apertures toward the corresponding photoelectric element by the corresponding specular surface of a polygon mirror. CONSTITUTION:An inspecting device makes reflected light from a part in a visual field of an aperture 74 of a slit on the surface to be inspected, to which an optical beam is irradiated, made incident on a photoelectric element 90 through the aperture 74, moves the visual field of the apertures in the scanning direction on the inspection surface, and decides whether a foreign matter exists on the surface to be inspected or not, etc., based on the output signal of the photoelectric element 90. In this regard, plural pieces of apertures 74 are provided, and in accordance with the respective apertures 74, the photoelectric element 90 is provided. The reflected light which has passed through the aperture 74 is reflected toward the corresponding photoelectric element 90 which is placed in the periphery of a polygon mirror 88, by the corresponding specular surface of the pyramid-shaped polygon mirror 88. In such away, even if each aperture 74 is made small, the inspection time can be shortened by enlarging a scanning pitch, and also even in case of a large-sized photoelectric element 90, a small mounting space will suffice.

Description

[Detailed Description of the Invention] [Field of Application in Industry-1-] This invention is a method for measuring the number of people on a surface to be inspected, such as the surface of a wafer for LSI. (Related to a foreign substance inspection device that automatically performs inspections such as

[Prior Art] As a cheap inspection device for LSI wafers, reflected light from a portion within the field of view of a slit aperture on a surface to be inspected irradiated with a light beam is transmitted to a photoelectric element through the aperture. There is a type of device in which the field of view of an aperture is moved in the scanning direction on the surface to be inspected, and the presence or absence of foreign matter on the surface to be inspected is determined based on the output signal of the photoelectric element-r.

In such a conventional foreign matter inspection device, the number of apertures provided in the slit for passing reflected light is 1.
There was only one.

[Problem to be solved] The output signal of the photoelectric device has problems related to foreign matter (+, “J”).
In addition to the acid component, it also contains background noise determined by the hearing condition of the surface to be inspected. The S/N of that signal is 1-
In order to make it possible to detect minute foreign objects, there are seven ways to reduce the aperture of the slit.

However, conventionally, the slit has only one aperture, so if you try to reduce the aperture by 1 minute, it is necessary to pinch the scanning line (view of the aperture! movement trajectory of the IF) in order to completely cover the front surface of the subject. There was a problem that the inspection time was significantly increased.

Another problem is that when the aperture is made smaller, the level of the output signal from the photoelectric element is lowered, and the electric circuit associated with the transmission becomes complex and expensive.

[Purpose of the Invention] This invention was made in view of such problems in the prior art, and its main object 1-1 is to shorten the inspection time even when the slit aperture is reduced by 1 minute. The object of the present invention is to provide a foreign matter inspection device.

[L stage for solving the problem] In order to achieve such an objective, in this invention, a plurality of apertures are provided in the slit, and a photoelectric element is provided corresponding to each aperture, and a photoelectric element is provided in correspondence with each aperture. The reflected light from the crystal surface to be tested is separated into light components 1lIIr' by one stage and made incident on the corresponding photoelectric elements.

A photomultiplier is often used as a photoelectric element due to sensitivity and other factors, but since it is quite large, one person needs to use an illuminating device to reduce the mounting space.
It is. Therefore, in this invention, +1 optical separation r
By using a pyramid-shaped polygon mirror as a stage, arranging each photoelectric element -r around the polygon mirror, and reflecting the light passing through each aperture toward the corresponding photoelectric element by the corresponding mirror surface of the polygon mirror. , reducing the mounting space for photoelectric elements.

[Operation] The optic kidneys of the front surface 1- of each aperture to be examined are distributed in the scanning direction and the direction orthogonal thereto, and each Since the apertures can be arranged, even if the individual apertures are made smaller, the scan line pinch can be increased and the inspection time can be shortened.

Since the photoelectric element is placed around the polygon mirror, even if a large photomultiplier is used as the photoelectric element,
The mounting space always requires less space.

[Embodiment] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an aS diagram showing a simplified configuration of the optical system and other parts of the wafer foreign matter inspection apparatus according to the present invention. Second
The figure is a schematic diagram of the signal system and processing control system of the device.

First, in FIG. 1, reference numeral 10 is an X stage supported by a base 12 so as to be able to slide 117 in the X direction. A screw 16 directly connected to the rotating shaft of a stepping motor 14 is screwed into this X stage 10, and by operating the stepping motor 14, the X stage 10 can be moved forward and backward in the X direction. can. 18 is a linear encoder that generates a code signal corresponding to the position X of the X stage 10 in the X direction.

A Z stage 20 is attached to the X stage "11O" so as to be able to move i+J in the Z direction.The moving stage is omitted in the figure.A wafer 30 as an object to be inspected is mounted on the Z stage 20. The rotation stage 22 placed on it rotates iI
It is supported by Noh. This rotation stage 22 is connected to a DC motor 24, and is rotated by operating the DC motor 24. This DC motor 24 has a built-in rotary encoder that outputs No. 1 to the code corresponding to the rotation angle position 0.

Note that the wafer 30 is positioned on the rotation stage 22 by negative II suction. '! However, the first stage for this purpose cannot be omitted in the figure.

This foreign matter inspection device uses polarized laser light to
01- is automatically subjected to Mi"N, and the S-polarized laser beam is irradiated onto the wafer 30 (tested). Therefore, the S-polarized laser oscillation Z38.38 Each S-polarized laser oscillator Z438.38 generates S-polarized laser light of a certain wavelength, and is, for example, a 1/- conductor laser oscillator with a wavelength of 8300 angstroms.

The S-polarized laser beam is emitted from the X direction toward the wafer 30, for example, at an angle of 2" Ij (one angle of incidence. Since the irradiation angle is small in this way, the beam of S-polarized laser light with a circular cross section In this case, the spot on the wafer extends inward in the
Place the lindrical lens 44.46 in front of the
The wafer is irradiated with an S-polarized laser beam that has a flattened cross-section in the Z direction, and the spot shape is made close to a circle to increase the irradiation density.

The reflected laser light of the S-polarized laser light irradiated onto the wafer is! I((If the projection surface is microscopically smooth, then S
There are only polarized components. For example, if a pattern exists, it is microscopically considered to be ten-dimensional, so that the reflected laser light can be considered to have only an S-polarized component.

Other spit! j (When a foreign object is irradiated with one shot, the surface of the foreign object generally has minute irregularities, so j! (Single shot S-polarized laser light is scattered and polarized) J direction changes. As a result, in addition to the S-polarized component, the reflected laser light also contains the P-polarized component.
It will contain a considerable amount of polarized light components.

This phenomenon is based on the level of the P-polarized component contained in the reflected laser light from the wafer.
-jjiij and the size of the foreign object are detected. This is this W
Physical inspection^ This is the detection principle of the device.

Refer to Figure 1. One laser beam emitted from the wafer enters an optical system common to a detection system 50 for detecting foreign matter according to the principle described in 1liI and a microscope 52 for 11-view observation of the wafer. That is, the reflected laser beam passes through the objective lens 54, the half mirror 56, and the prism 58 through 111 and reaches the 45-degree prism 1 and 60.

Further, a lamp 70 is provided for 11-view observation. The visible light emitted from this lamp 70 causes the half mirror to
56 and the objective lens 54, the wafer 11 (1
It will be revealed. In addition, the 45 degree prism 60 and the 60 degree prism 62 are structured to be put in the middle of the optical path.
At the time of inspection, 45 degree blur 0 is placed in the middle of the optical path, and at 11 viewing, 60 degree blur and 62 are placed in the middle of the optical path.

Blizz T, I entered the microscope 2 side after passing 60 and 111
The reflected light passes through a 60-degree prism 62, a field lens 64, and a relay lens 66 in order and enters the eyepiece 6.
8. Therefore, the wafer 30 can be observed 11 times through the eyepiece lens 68 at a magnification that is one minute larger. In this case, the wafer's S-polarized laser beam is at the center of the field of view f! 1 (the first shot area is located.

The wafer 30 can also be observed at low magnification through the prism 58.

The reflected laser light that has entered the detection system side via the prism 60 passes through four apertures 74 provided in the slit 72.
The light passes through the S-polarized light cut filter (polarizing plate) 86, and only the P-polarized light component is extracted. The extracted P-polarized laser beam enters the separation mirror 88.

Four apertures of Surishito 72 44; i T bird 4
The mirror 88 is a four-sided mirror in the shape of a square X1. The incident surface of the 4t mirror 88 1. As shown in FIG. 3, the field of view 74A of the h aperture 4 in FIG.

The P-polarized light component of the reflected laser light that has passed through each aperture 4 is incident on the corresponding mirror surface 88A, and is separated and reflected in the J direction (which is substantially orthogonal to Ij).

Minute M mirror 88! - Photomultipliers 90 (electronic JJ') corresponding to each aperture 4 are provided on the left and right sides. The P-polarized laser light emitted by each mirror surface 88A is incident on the corresponding photomultiplier 90, and is converted into light 11i.

In this way, since the apertures 74 are arranged in an island shape, the laser beams passing through the four apertures 4 are separated by the separation mirror 88 (nine separation steps) in the cylinder into a corresponding photomultiplier. It can be made to enter the pliers 90.

Here, for example, if the four apertures 4 are arranged linearly as shown in FIG. 9, it is difficult to separate them at once using a mirror or prism. This is because unless the difference in the relative position between the aperture 4 and the mirror or prism is kept small, they will be separated at an inappropriate position. Even if we assume that each aperture 4
As shown in the figure, there are 7 waves that bend partially in a certain direction (perpendicular to the scanning direction), so the separation boundary is not linear, and a 6-shaped mirror or prism is required. It is from.

Therefore, in the case of such a linear arrangement, 11 beams are separated once with the (, 'I position) in Figure 9 as a boundary, and 21111I+ beams are further separated with the boundary in the ■ position. 11. This requires three mirrors or prisms on one side, and blurring due to two reflections or refractions is likely to occur.In addition, regarding the separation of each time: As in the case of position 1, the separation is likely to be incomplete because it is easily affected by the difference.

On the other hand, in the case of the T-bird arrangement, as is clear from Fig. 3, the spacing between adjacent apertures is 1/Kinin in each orthogonal direction, so the above-mentioned separation of 1111 The mirror 88 allows light separation to be performed at -.degree. Also, the relative position of the aperture 4 and the separation mirror 88 is 1°I, l! Even if you don't restrict the 1 difference so strictly,
Complete separation is possible.

Also, although the photomultiplier 90 is quite large,
Since they are arranged on the left and right sides of the mirror 88, the minimum space is required.

Now, each photomultiplier 90 outputs a detected value i, S;, which is proportional to the respective incident light H,(.As will be described later, the output (+'jSJ - is added, and based on the added level (No. 11), it is determined whether or not there is a foreign object on the wafer (strictly speaking, the part within the field of view of each aperture 4), and whether there is a foreign object or not. If so, the particle size of the foreign object is determined from the level of the particle size.

Here, the physical inspection is performed while simultaneously rotating the wafer and feeding it in the X direction ("M'Y direction") as described above.Following such movement of the wafer 30, as shown in FIG. , the irradiation area 30A of the S-polarized laser beam is 1- of the wafer 30.
move in a spiral from the outside towards the center. The detection system 50 and the microscope 52 are in a static state, and the field of view of the aperture 4 is included in the irradiation area 307~, and That is, the wafer is helically scanned.

The field of view 74B of each aperture 4 of the pick-up y+-72 on the Ueno\ plane is arranged in a very small arrangement as shown in FIG.

Like the same car, the field of view 74B of the adjacent aperture is in the horn direction perpendicular to +TE with respect to the scanning direction (θ direction), that is,
The direction is αtakeichi. And β is Ueno's X
It is easier to feed in the direction (radial direction ゛1') than the pinch. Therefore, is it a city? It will be scanned at V t.

Now, the photomultiplier outputs (+j−
In addition to the 4+ and J acid components related to foreign objects, J also contains background noise determined by the state of the front surface of the test object. y
In order to improve the detection of Is objects, there is a method of reducing the aperture of the slit. However, in the case of a single aperture, as mentioned above, a smaller aperture increases the time to scan the entire subject.

Therefore, in this embodiment, four apertures are provided (generally, three sides are one), and the width β of the overall field of view of all the apertures in the scanning direction and the vertical direction is expanded. In the case of a small size, the number of scans is increased by 6 bits, thereby achieving an improvement in detectability and a reduction in scanning time.

In addition, in order to eliminate the difference in the detection of foreign objects by /d direction, as described later, the output of each photomultiplier that detects the scattered light emitted from different directions is 4. i number is added.

Next, the J system and processing control system of this single object inspection apparatus will be explained by referring to FIG. 2.

First, the +jSJ system will be explained. The output signals of the photomultipliers 90 are amplified by the summing amplifier 100 and input to the level comparison circuit 102.

Here, there is a relationship as shown in FIG. 6 between the particle size of the foreign matter on the wafer 1' and the output 4+C'i level of the photomultiplier 90. In this figure, L7, L2
, LJ are threshold values of the level comparison circuits 102 and 106.

The level comparison circuit 102 is operated by each human power 4+';"J
The level of ' is compared with each threshold value, and an output of 1 and a bow corresponding to the logical level threshold χ·1 is sent out according to the comparison result.

That is, the lines l1fh, Lz, L2, L,?
The logic level of the output 4W"tOi + 02.03 corresponding to 4W"tOi + 02.03 becomes "1" when 4+jSJ' with a level of 1., below the dark value is input, and the input L';"J level reaches the end of the threshold ff4 Therefore, for example, if the input level is less than the threshold L/, all output signals will be 0, and the input signal level will be 0 when the input signal level is less than the threshold L2.
If the threshold value is less than J, the output signal is O1 and 02 are “
l”, 03 becomes “0”.

In this way, the output signal 'yO1+02+03 is a small binary code that represents the level comparison unity of the input signals 1 and -J.

The output L knee J” of the level comparison circuit 102 is the code L (
The data is manually input to the interface circuit 108, which controls the interface between the processing control system and the A, 1-NO systems, as a binary code with 0/ as the lIλ digit bit.

This interface circuit 108 receives a signal (binary code) from the rotary encoder and the linear encoder that reduces the information of the rotational angle position 0 and the X force (radial direction) position X at each point in time.・Circuit 1
10. Manually powered via 112. These input codes are: - taken into a certain register inside the interface circuit 10g at regular intervals, and temporarily held there.

Also, inside the interface circuit 108, there is a register in which control information for the motor 14.24 is set by the processing control system. Cents were placed in this register; 1. According to the control information, the motor controller 116 controls the motor 1.
4.24 drive control is performed.

Next, the processing control system will be explained. This processing control system is a microprocessor 120. ROMI22, RAM
124, a floppy disk device 12B, an X-Y plotter 127, a CRT display device 128, a T-board 130, etc.

t32 is a / stem bath and microbrosé! Su12
0, ROM 122, RAM 124, and the interface circuit 108 are connected to the 11° port.

The keyboard 130 is used by the operator to input various commands and data, and is connected to the 7-stem bus 132 via an interface circuit 134. The floppy disk device 126 stores the operating system, various processing programs, test result data, etc., and is connected to the system bus 132 via the floppy disk controller 13B.

When this W product 49A device is started, the operating 7 stem is transferred from the floppy disk device 126 to the RAM.
124 system area 124A. Thereafter, one or more necessary processing programs 1 from among the various processing programs stored in the floppy disk device 126 are transferred to the program area 124B of the RAM l 24.
is loaded and processed by microprocessor 120.
be done. Data that is being processed is stored in RAM l24f.
' + Temporarily stored in the business area. The processed binding data is
Finally, it is transferred to and stored in the floppy disk device 126.

The ROM 122 stores dot patterns of letters, numbers, and symbols.

The CRT display device 128 is used to display the size of various messages for dialogue with the operator, as well as the size of physical maps and other data. Ru. 140 is a video controller, and a video RAM
In addition to controlling +'F loading and reading of 138, it also generates video signals according to dot patterns, generates cursor patterns, etc. This video controller 140 connects to the system bus 130 via an interface circuit 142.
It is connected to the. A cursor address pointer 140A for controlling the address of the cursor is provided in the video controller 140, and this pointer is incremented or decremented according to a cursor control signal from the keyboard 130.
20 allows access IIJ functionality.

The X-Y plotter 127 is used for printing out images, etc., and is connected to the computer and bus 132 via a plotter controller 137.

Next, the W object inspection process will be explained with reference to the flowchart shown in FIG. Here, foreign body automatic @An,
Although the 1111 type is used to specify jobs such as 11 visual observation and printing by the operator, this is just an example.

With the wafer 30 set at a predetermined position on the rotation stage 22, when the operator issues a command to start the inspection from the keyboard 130, the inspection processing program is transferred from the floppy disk device 126 to the PROGERA LB art in the RAM 124.
Loaded into area 124B and started running.

First, the microprocessor 120 performs initialization processing.

31 Physically, the X stage lo and the rotation stage 22
Motor control information for positioning the motor to the initial position is set in eleven registers of the interface circuit 108. According to this motor control information, the motor controller 11B controls the motors 14 and 24 to move each stage to its initial position. In addition, the microprocessor 120
is a storage area for tables, counters, test data buffers, etc. (see Figure 2).
201- (those storage areas will be cleared).

A conceptual diagram of the It table (created in the table area 1241) is shown in FIG. Each entry in this table 150 includes the location of the foreign object (in the order in which it was detected), the position of the foreign object (detected scanning position X, 0), and its type or nature (
(as determined by 11-view observation), and particle size.

After the initialization, a job menu is displayed on the CRT display device 128, and the system waits for job designation from the operator.

The flowchart in FIG. 8(A) shows the flow of processing when an "automatic inspection" job is specified. ! (I will explain later.

Once the autotest code is entered into the microprocessor 120 through the keyboard 130, the microprocessor 120 begins the auto-bonding process. OK, the microprocessor 120 instructs the motor controller 116 to start alignment through the interface circuit 108 (step 210). Upon receiving this instruction, the motor controller 116 performs the above-mentioned spiral scan at a constant speed.
The motors 914 and 24 are driven so as to cause 4I.

The microprocessor 120 is the interface circuit 1
08 specific internal register contents, i.e. wafer 3
0 scanning position X, 0 code, and level comparison circuit 102
The input data consisting of the code L, which is the level comparison result by
Input jF into 4C (step 215).

The microprocessor 120 determines the end of the scan by comparing the quantity information of the captured scan 4r' with the period information of the position of the scan path r4-' (step 220).
.

If the result of this determination is No (in the middle of the upper half), the microprocessor 120 makes a zero determination of the loaded code L (step 225). If L2000, its scan 1
There are no foreign objects in 1-6.

If L≠000, is there a foreign object? 71.

If the determination result in step 225 is YES, step 21
I'll be at 5. If the determination result in step 225 is No,
The micropro sensor 120 receives the captured position information (x
, /7) and the positional information of other detected foreign objects stored in the table 150 +1J(x.

θ) (step 230).

If the location information is confirmed, the foreign object in the current 71 is located in another yd.
The process returns to step 215 because it is made to look the same as a physical object.

If the comparison of location information is negative or negative, it can be assumed that a new foreign object has been detected. Therefore, the microprocessor 120
The counter N, which is the area 124E secured in the RAM 124+-, is incremented (step 235).
. Then, in the entry 8 and 11 of the table 150, the position information (x, 0) of the foreign object and the code L (U-
-1 is input (as the diameter information) (step 240).

Similar processing is repeated until the scanning of the wafer 30 is completed.

Once the scan paths r and 'I'l+ have been determined in step 220, the mask 120 is
A scan stop 1 command is sent to the motor controller tte (step 250). In response to this instruction, the motor controller 11B stops driving the motor 14.
do.

Next, see table 150 for microbrosée 120! ! (i t,, if hood L is 12 foreign objects; 1 number T
If L/N code 11L is 32 foreign objects, 11 number T L 2
The total number TL3 of ηS objects with N code L of 72 is defined as l S
'l: L, the total number of foreign objects data is stored in RAM1241.
1F is written into the specific areas 124F, 124G, and 124H of t (step 251). Then, the stored contents of the table 150 and the foreign matter total data are transferred to the floppy disk device 126 with a waferization mark added thereto and stored therein (step 252).

This completes the automatic inspection job, and a menu is displayed on the screen of the CRT display device 128.

Next, the process flow of "11 visual observation" will be explained using the flowcharts shown in FIGS. 8(B) to 8(E). I
I visual inspection includes sequential mode, all-3 designation mode, and cursor designation mode, which can be designated from the keyboard 130.

When the job and mode of II visual observation are designated, the micro processor 120 causes the DMA transfer of the Dobdoputter 7 data of both contour images of the wafer from the floppy disc device 126 to the video RAM 13g (step 28
5). This umbrella! Starting S-transmission; 1. II 8 by microprocessor 120? 1: However, subsequent transfer control is performed by the video controller 140 and the floppy disk controller 1.36. Video RA
The pattern data of M138 is sequentially read out by the video controller 140, converted into a video signal, and sent to the CRT display device 12g, where it is increased or decreased in size.

Next, the microprocessor 120 has a floppy disk device to which the observation pair 'ρ wafer pattern (input from the keyboard 130 in job selection 11.5) is added.
The memory contents of table 150 stored in 28 and SO4
The total number of objects data is read and 3IF written into the corresponding area of the RAM 124 (step 290).

The microprocessor 120 sequentially reads the position information and size information (L code) of each foreign object from the table 150 in the 124 ft RAM, reads the dot pattern data corresponding to the L code from the ROM 122, and stores the data in the video RAM 138 corresponding to the position information. It is transferred to the video controller 140 along with the address information and stored in the video RAM 1.
38 ;l) is written (step 295). Through this process, the map of the foreign matter stored in the table 150 is displayed on the screen of the CRT display device 128.

Next, the microprocessor 120 instructs the motor controller 116 to position the scanning position to the initial position via the interface circuit 108 (step 30
0). The processing differs depending on the specified mode.

If sequential mode is specified, the microprocessor 12
0 is 1 in counter M (area 124J of RAM 124)
(step 320), and reads the data of the foreign object (the foreign object detected at M number 11) stored in the entry of number M 1-1 in the table 150 (step 325).
. Then, control information for moving the scanning position to the position corresponding to the position information (x, /7) is sent to the motor controller 116 via the interface circuit 108.
(step 330). Motor controller 116
When the motors 14 and 24 are controlled by , and the proper position is determined, naturally, the center of the field of view of the optical microscope 52 will be the M axis [1'/l! Things are located.

The microprocessor 120 generates the II, J pattern corresponding to the L code of Mδ[1, and the 1st 11th (P is RA
One foreign object pattern corresponding to the foreign object code (counter P value) is read out from the ROM 122 in the area 124 of M124, and the foreign object pattern of No. 1 and 11 is left as is.
The pattern of 1° 11 objects is 1° inverted 1-, and is sequentially transferred to the B/O controller 140 along with address information, (
Insert these patterns into the corresponding address of Biddy RAM,
1: Capture and express (Suminobu 335). Now the CRT
Tisfret 4 volumes: ;'; 128 b') Picture + fi
Foreign body 7 nopt, M number) 1 +1' that is living in +
, 4 objects f 2 are inverted patterns,! :1. It becomes Kokichi, who is appointed, and is visually separated by 1x from the Hanami thing in the pond.

Microblossom 120 is ink-face circuit 1
Even through 08, the ``I position information is sequentially taken in, and N1 each II
It is compared with the quantity information of ``I'' of ``1'' of ``1'' to determine whether the placement of ``1'' is complete (step 340). Once the positioning is complete, the microprocessor 120 performs observation +
1J Noh message is transferred to the bidy RAM 138 and displayed on the screen of the CRT display device 128 (
X? knob 345). And the key human power is samurai-)(
step 350).

Operate is I/, i object 11 view IIM view 11,
・Identify the quality or kind of i thing ↑ to 1 of ε, and write the 11 types of codes that do not have that quality on the keyboard 130 ↓] Person 0
:,Q゛゛Actually, by specifying the 11 viewing function, the screen of the CRT display device 128 is changed to 11, byte class 1, which does not have the property of 5'+1 object. Gino's table is filled with personnel information, so enter the appropriate number in that table.

If the minor 0b [J seta 120 is the property of a foreign substance or +p class: 1-do (step 352)
, enter that code into the 1st integer of M scatter [1 +”F in table 150 (step 355). However, if the manual code is another code with a tab, enter
is skipped.

Next, the microprocessor 120 generates a counter M,
P is incremented by 1 (step 360), and a comparison is made between counter M and counter N (this value is the total number of detected foreign objects of 1.1) (step 365). If M<N, the process returns to Step 325.

Also, if M≧Nf, the table of RAM1381.
150 memory contents and foreign matter, ij'F! 70I B disk 'A, 12 B
Transfer to Stave 370), job menu double-sided σ
The 1st to the 1st, the cameras bow, the specified mode, the specified No. 1, the microscessor 120 has 14 insult -no input from the operake (step 41Q). When the key is manually operated, it is determined whether the human-powered hood or lAi product number is the same (
step 415). If not, wait for key personnel.

When γ11 insult-no is keyed, microprocessor I
Is Su120 that foreign object? Set fr'I3 to counter M,
(step 420), proceed to step 325.

Thereafter, in step 357, the value of the counter M is changed to the value of the counter P.
In the next step 400, it is determined whether the current mode 71 is the No. 6 designation mode or the cursor designation mode. Since this is the number designation mode, the process goes to step 410 (1).

In the same way, by manually pressing the keys I and ¥3, the specified object is automatically positioned at the approximate center of the field of view of the Wl microscope 52, and the 11th observation is made. The unity of No. 1 in the corresponding entry in Table 1.50
I can get 1 in.

In addition, in the 70-chart, if j (not 1) is entered, but if the end r key of the keyboard 130 is input at this point, the city specification mode will end, and after the processing in step 370, the job will be Go to the menu 11i1bi state.

The cursor specification mode will be explained. In the cursor specification mode, the operator operates the cursor operation keys provided on the keyboard 130 to
Cursor address pointer 1 through cursor control signal
1+ of 4OA and 128 CRT display devices
The foreign object to be observed is designated by moving the cursor displayed on the screen to the position of the target foreign object, which is also displayed on the screen, and pressing the cursor read key on the keyboard 130.

In this mode, the microprocessor 120 waits for a key input (step 430), and when a key input occurs, it determines whether it is the code for a cursor read key (step 435). If the determination result is NO, the process will wait for key personnel.

If the decision is unity or YES, it will be microbrosé.

Step 120 reads the contents (cursor address) of cursor address pointer 140A (step 440).

Then, the cursor address is converted to the corresponding correct combination, that is, 11 things, 1, 1, and 1 v (step 445).
).

Next, search the table 150, and compare the obtained W object and the λ° device with each foreign object stored in the table 150, and search for the closest)+, i object.
Step 450), and set the foreign object 6-;' on the trigger M (step 455). And step 325
Proceed to.

In this way, the object specified by the cursor is automatically determined to be the object f of the microscope, and its observation result is entered into the corresponding entry in the table 150.

Although the national hand has not been played, if the end r key on the keyboard 130 is pressed, the process branches to step 370, and after the end r, the state is set to ``R'' selection ++In +f+i.

By performing the 11th observation in 1life, you can obtain a table that integrates the 1st observation and the automatic verification.

In the 11-view observation, the foreign object being observed is displayed on the CRT display device 128 on the foreign object map 1.
Since the size is displayed as an inverted pattern, the operator (observer) can easily check the foreign object being observed using a foreign object detector.

If you specify "Print" on the job selection screen, +'j! You can print out all the results from YPro 127.

When printing is specified, as shown in Figure 8 (F),
The microprocessor 120 reads out the wafer contour image data from the flow disk device 126 and transfers it to the plotter controller (step 465).
.

Next, the microprocessor 120 prints the wafer number 3 (manually entered from the keyboard 130 when selecting a job) and stores it in the disk unit 12B. Memory contents of table 150 and 5'H3 combination 1. The data are sequentially read out and transferred to the plotter controller 137 (step.

470).

Thus, the foreign matter map, table contents (table), total number of foreign matter data, wafer 1l19 II is X-Y Bronta 1
Printed on 27th.

When printing is finished, the state returns to 2I print selection 111r+i.

The embodiments of this invention have been described in 1.1 below.
This invention is not limited to this, but can be implemented with appropriate modifications.

For example, it is not always necessary for the correct position of the inspection system 50 to always enter the microscope 52.
It is sufficient if the positional relationship between the position and the visual field 'i'f is maintained. However, if the above embodiment is adopted, processing such as identification of foreign objects during 11-view observation is easy.

Instead of the photomultiplier, other suitable photoelectric elements can be used.

Scanning is limited to spiral alignment; for example, linear scanning may be used. However, since the front of the curve stops at the scanning end, the scanning time tends to increase.Also, when scanning the front surface of a circular object such as a wafer, the scanning end (: 1 position control or N
There seems to be a tendency for it to be on the 21st floor. Therefore, in the case of wafer inspection, spiral alignment is generally advantageous.

Moreover, it goes without saying that the present invention can be similarly applied to a foreign matter inspection apparatus of 7 m + QA other than wafers. Further, the present invention can also be applied to similar foreign matter detection devices that utilize light beams other than polarized laser light.

[Effects of the Invention (Part 1) As explained above, according to the present invention, a plurality of apertures are provided in the slot and gate, and a photoelectric element is arranged in correspondence with each aperture. The reflected light from the detection surface is separated by a square mirror and incident on the corresponding photoelectric element, and since each photoelectric element is arranged around the multiple tube, the individual apertures can be made small and C
In addition, it is possible to reduce the inspection time by 1υ by increasing the upper front pitch, and it is also possible to reduce the inspection time by 1υ.
Even if it is adopted as a photoelectric element, the mounting space can always be reduced. Figure 2 is a schematic block diagram of the same two-piece inspection device. Figure 3 is a schematic block diagram of the bow system and processing control system. Fig. 4 is an explanatory diagram of the correspondence between the aperture arrangement and the mirror surface of the separating mirror; Fig. 4 is an explanatory diagram of alignment of the test crystal plane; Fig. 5 is an illustration of the alignment of the test crystal surface in Explanatory diagram regarding vision!I!F, Figure 6 is l, llj
Thing ti'? i) F and the output of the photomultiplier,
The relationship with No. 5 and the relationship with the level comparison threshold are shown in a small graph, FIG. 7 is a conceptual diagram of a table related to inspection processing, and FIG. 8 (A) to F) is a flowchart of processing related to inspection processing. FIG. 9 is an explanatory diagram regarding light separation when the apertures of the slits are arranged in a curved manner.

10...X stage, 14.24...Motor, 22
... Rotating stage, 30... Wafer, 36.38.
... S-polarized laser light vibration Z4.44.46 ... Norindrical lens, 50 ... detection system, 52 ... microscope,
12...Slit, 74...Aperture, 86...
・S polarization cut filter, 88... Separation mirror, 90
...Photomultiplier, 100...Additional p amplification Z4
, 102...Level comparison circuit, 108...Interface circuit, 116...Mode controller,! 2
0...Microprocessor 122...ROM, 12
4...RAM, 12B...floppy disk device, 127...X-Y plotter, 128...CRT display device, 130...keyboard, 138...
-Video RAM, 150...table.

Mochi 1, 1 Outgoing Person 11 ~ R Electric Engineering Co., Ltd. Agent Patent Attorney 1
- Nobu Kajiyama Foot A3 Closed 52nd %B 4th-Q

Claims (1)

[Claims] (1) Reflected light from a portion of the surface to be inspected that is irradiated with a light beam within the field of view of the aperture of the slit is incident on the photoelectric element through the aperture, and the field of view of the aperture is set on the surface to be inspected. In the foreign matter inspection apparatus that moves in a scanning direction and determines the presence or absence of foreign matter on the surface to be inspected based on the output signal of the photoelectric element, a plurality of apertures are provided, and the photoelectric element is provided corresponding to each aperture. and the reflected light passing through each of the apertures is reflected by a corresponding mirror surface of a pyramidal polygonal mirror toward the corresponding photoelectric element arranged around the polygonal mirror.