JP2003152037A - Method and apparatus for inspecting wafer as well as inspecting infrared imaging unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the time of inspecting a wafer and to improve the inspecting accuracy by accurately bringing the electrode formed on a tester probe in contact with the circuit electrode of an IC chip in a short time. SOLUTION: The method for inspecting the wafer comprises the steps of imaging the image of the circuit pattern on the upper surface of the wafer (3) and the image of the tester probe through the wafer (3) by an infrared camera disposed under the wafer (3) in the case of positioning the tester probe (7) directly above the arbitrary IC chip (2), and relatively moving the probe (7) at the position in which the circuit electrode (5) is superposed on the tester electrode (6) based on the image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer inspection method, an inspection apparatus and an inspection infrared image pickup apparatus for inspecting a circuit for each of a large number of IC chips formed on a wafer.

[0002]

2. Description of the Related Art ICs are called LSIs or VLSIs depending on the degree of integration of circuit elements.
A circuit pattern for hundreds of IC chips with a size of several millimeters square is formed on the surface of a disk-shaped silicon wafer having a thickness of about 30 cm and a thickness of about 0.5 mm, which is then cut into individual IC chips and then connected to external electrodes. Wire bonding is performed between them, and this is sealed in a casing to form one electronic component.

If there is a defect in the circuit pattern, the work after cutting into individual IC chips becomes useless. Therefore, product inspection of the IC chips is performed before cutting into individual IC chips, and defective ICs are inspected. An inkjet marker is attached to the chip so that the chip can be identified.

FIG. 4 is a view showing a conventional inspection apparatus 41, which is provided above a table 44 for fixing a wafer 43 having a large number of IC chips 42 formed thereon with its circuit surface facing upward.
A tester probe 47 having a large number of tester electrodes 46 that are simultaneously in contact with all the circuit electrodes 45 of one IC chip 42 is movably arranged in the XYZ directions.

It is necessary to position the electrodes 45 and 46 on the order of microns, and in some cases on the order of submicrons. Therefore, between the table 44 and the tester probe 47, two wafer imaging cameras 48A and 48B having different imaging magnifications are used to detect the position of the wafer 43.
Is built in the wafer position detecting bridge 49 which is reciprocally moved in the X-axis direction with the optical axis facing downward. Further, next to the table 44, a coordinate correction fixed camera 50 for detecting the positional displacement of the tester probe 47 and the positional displacement of the bridge 49 is arranged with the optical axis facing upward.

A case where a wafer inspection is performed using this inspection device 41 will be described. [Process A: Inspection Preparation Work] Position Confirmation of Tester Probe 47 Position the tester probe 47 at preset coordinates,
Tester electrode 46 that serves as an index with the fixed camera 50 for coordinate correction
Is imaged, and if there is a position shift, the coordinates are corrected based on the shift and the tester probe 47 is retracted upward. Confirmation of Position of Wafer Position Detection Bridge 49 Similarly, the wafer position detection bridge 49 is also positioned at preset coordinates, and the fixed camera 50 for coordinate correction is used.
One of the wafer imaging cameras 48A, which serves as an index, is imaged, and if there is a positional deviation, the coordinates are corrected based on the deviation, and the inspection preparation is completed. This step A is to determine the reference positions of the tester probe 47 and the bridge 49, and since slight deviation is not allowed, it is always performed every time the wafer 43 is inspected. [Step B: Confirmation of Wafer Position] After the inspection preparation is completed in this way, the wafer 43 is fed onto the table 44 and vacuum sucked onto a plurality of suction holes (not shown) formed on the table surface. Fix it. Then, the wafer position detection bridge 49 is scanned in the X-axis direction, and the low-magnification imaging camera 48A is scanned.
The circuit pattern of the wafer 43 is picked up at, the pattern is compared with the pattern stored in advance, the center coordinates are measured from the outer circumference of the wafer 43, and rough alignment is performed to correct the rough positional deviation on the coordinates. Then, bridge X again
Scan in the axial direction and use the high-magnification imaging camera 48B to scan the wafer 4
The circuit pattern of 3 is imaged, and fine alignment is performed to accurately correct the positional deviation on the coordinates. This step B is
This is performed every time the wafer 43 is supplied. [Step C: Positioning of Tester Probe 47] When the position where the wafer 43 is placed is detected in Step B, the coordinates of each IC chip 42 are calculated based on this, and the tester probe is set to the calculated coordinates. Position 47. [Step D: Inspection] After the tester probe 47 is positioned, when the tester probe 47 is lowered by a predetermined distance, the tester electrodes 46 come into contact with all the circuit electrodes 45 of the IC chip 42. Each IC chip 42 is inspected, and thereafter, steps C and D are repeated to inspect all the IC chips 42 on one wafer 33.

[0007]

However, when performing a wafer inspection in this way, it takes time because there are many objects to be confirmed such as the wafer 43, the tester probe 47 and the wafer position detecting bridge 49. There is a problem.

Further, when the optical axis of the coordinate correcting fixed camera 50 is the Z axis passing through the mechanical origin of XY coordinates, the position confirmation of the tester probe 47 and the wafer position detecting bridge 49 by the coordinate correcting fixed camera 50 is confirmed. Is only for detecting the positional deviation when stopped at the mechanical origin. Therefore, even if the wafer position detecting bridge 49 is scanned in the X-axis direction to detect the wafer position, it is not possible to eliminate the backlash of the wafer position detecting bridge 49 and an error caused by thermal expansion.

Further, the tester probe 47 is moved to the coordinate point of the IC chip 42 calculated based on the detection data of the wafer position detecting bridge 49. In this case as well, whether the tester probe 47 is really moved to the coordinate point or not. I can't confirm. Therefore, in reality, an IC with no circuit abnormality
There is a possibility that the chip 42 may be determined to be a defective product, and the yield may be deteriorated.

Further, the table 44 and the tester probe 4
Since a clearance of at least about 6 cm in the height direction must be ensured as a space for the wafer position detection bridge 49 to reciprocate between 7 and 7, the tester probe 4
7, the moving distance in the Z direction becomes longer, and the tester electrode 46 becomes an IC
There is a problem that it takes time to contact the circuit electrode 45 of the chip 42, and the error increases as the movement distance increases.

In view of the above, the present invention has a technical object to accurately contact a tester electrode formed on a tester probe with a circuit electrode of an IC chip in a short time to shorten a wafer inspection time and improve inspection accuracy. I am trying.

[0012]

In order to solve this problem, the method according to the first aspect of the invention is to fix a wafer on which a large number of IC chips are formed with its circuit surface facing upward and to fix one IC.
After positioning a tester probe equipped with a large number of tester electrodes that are in contact with all the circuit electrodes of the chip at the same time directly on any IC chip, lower the tester probe to contact the electrodes. In a wafer inspection method for sequentially inspecting each IC chip for good and defective circuits, a circuit of a wafer imaged by an infrared camera from below the wafer when the tester probe is positioned right above an arbitrary IC chip. It is characterized in that the tester probe is relatively moved to a position where the circuit electrode and the tester electrode overlap based on the pattern image and the tester electrode image of the tester probe.

According to the first aspect of the present invention, since the circuit pattern formed on the upper surface of the wafer and the tester electrode of the tester probe are imaged by the infrared camera from below the wafer,
If the image pickup optical axis is fixed to an arbitrary IC chip and an image is picked up, the positional deviation between the circuit electrode and the tester electrode can be accurately detected.

That is, since it is possible to directly image each IC chip whether or not the electrodes overlap each other,
It is not necessary to accurately detect the position of the wafer in advance to determine the position of each IC chip, or to detect the position shift of the tester probe at the mechanical origin.

Further, since the circuit electrodes can be directly imaged from the lower side of the wafer by the infrared camera, the wafer position detecting bridge arranged above the wafer in the conventional inspection apparatus is not necessary. Therefore, the clearance between the tester probe and the wafer can be set to the necessary minimum, and the size of the apparatus can be reduced, and at the same time, the time required to move the tester probe up and down to bring the tester electrode into contact with the circuit electrode is shortened.

In order to carry out this method, the invention device according to a second aspect is such that a wafer having a large number of IC chips formed thereon is fixed to a table on which the circuit surface of the wafer is fixed, and the circuit electrodes of one IC chip are arranged on the table. A tester probe having a large number of tester electrodes contacted at the same time is relatively moved in the XYZ directions based on the circuit pattern image formed on the circuit surface of the wafer and the image of the tester probe to bring the electrodes into contact with each other. A wafer inspection device for inspecting good or bad of a circuit, wherein the table is formed of an infrared-transparent material, and infrared rays for imaging a circuit pattern and a tester electrode formed on a circuit surface of the wafer from below the table. The image pickup device is arranged so as to be movable relative to the table in at least the XY directions.

According to a third aspect of the present invention, at least two wafer imaging infrared cameras having a low image pickup magnification and a high image pickup magnification are focused on the circuit surface of the wafer fixed to the table, and above the wafer. An infrared camera for imaging a tester electrode that is focused by a tester electrode of a tester probe located at the same position and has an imaging magnification equal to the infrared imaging camera for wafer imaging with the high imaging magnification, and the imaging optical axis of each infrared camera is If an infrared imaging device equipped with an optical system that branches off from the main imaging optical axis of the book is used, the infrared imaging device can be used with the main imaging optical axis roughly aligned using a low-magnification wafer imaging infrared camera. Each electrode position can be accurately detected by using each infrared camera having a high imaging magnification without moving in the Z direction.

Further, as in the invention of claim 4, it is provided with two infrared cameras having a low image pickup magnification and a high image pickup magnification for focusing at the same point, and the image pickup optical axis of each infrared camera is one main. If an infrared imaging device provided with an optical system branched and formed from the imaging optical axis and arranged so as to be relatively movable in the Z direction along the main imaging optical axis is used, an infrared camera with a low imaging magnification is used. The position of each electrode can be accurately detected based on the image of the infrared camera having a high imaging magnification by moving in the Z direction in the state of being roughly aligned.

According to the invention of claim 5, a wafer imaging infrared camera which focuses on a circuit surface of a wafer fixed to a table and a tester which focuses on a tester electrode of a tester probe located above the wafer. If the infrared imaging device is provided with an infrared camera for imaging an electrode and an optical system for branching the imaging optical axis of each infrared camera from one main imaging optical axis, the infrared imaging device is moved in the Z direction. The circuit pattern of the wafer and the tester electrode can be simultaneously imaged by different cameras without any need.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a diagram showing an example of a wafer inspection apparatus according to the present invention, and FIGS. 2 and 3 are explanatory diagrams showing another embodiment.

FIG. 1 shows a wafer inspection apparatus according to a third aspect of the invention, which uses an infrared imaging apparatus according to the sixth aspect of the invention. In the wafer inspection device 1 of this example, all the circuit electrodes 5 of one IC chip 2 are above the table 4 on which the wafer 3 on which a large number of IC chips 2 are formed is fixed with the circuit surface facing upward. A large number of tester electrodes 6 ...
The tester probe 7 formed with is arranged so as to be movable in the XYZ directions with respect to the table 4.

In this example, the clearance between the tester probe 7 and the table 4 is initially set to be several millimeters, and when the wafer 3 is mounted on the table 4, the tester probe 7 is retracted upward or sideways. Is made like. Further, although the tester probe 7 is arranged so as to be movable in the XYZ directions, the table 4 or both may be made movable.
It suffices if it can move relative to the YZ direction.

The table 4 is made of an infrared permeable material, and in this example, a quartz glass plate that also transmits visible light is used. The surface of the table 4 is finished to be smooth, and the suction hole 4 for sucking and fixing the wafer 3 is fixed.
a is formed at a position corresponding to a portion of the wafer 3 where the circuit pattern is not formed.

Below the table 4, an infrared image pickup device 8 for picking up an image of the circuit pattern of the wafer 3 and the tester electrodes 6 formed on the tester probe 7 is arranged so as to be relatively movable in the XYZ directions.

The infrared image pickup device 8 has a low image pickup magnification (0.8) which is focused on the position F ₁ corresponding to the circuit surface of the wafer 3.
1.5-fold) and wafer imaging infrared camera 9A high imaging magnification (10-12 fold), focusing and 9B, the position _{F 2} corresponding to tester electrode 6 of the tester probe 7 positioned above the wafer 3 The infrared imaging camera 9C for imaging a tester electrode having a high imaging magnification (10 to 12 times) is provided, and these three infrared cameras 9A to 9C have their imaging optical axes R _{1 to} R ₃ as one main imaging optical axis. 1 attached to the optical system 10 branched from R
Is formed into a unit.

The infrared cameras 9B and 9C having a high imaging magnification have at least one IC chip 2 to be inspected.
It is desirable to select the imaging magnification such that all the circuit electrodes 5 and all the tester electrodes 6 can be imaged at the same time.

In this optical system 10, the half mirrors BS ₁ , BS ₂ and the mirror M for branching the main imaging optical axis R from the main imaging optical axes R _{1 to} R ₃ of the cameras 9A to 9C are housings. The infrared camera 9A, 9B is focused on the position F ₁ on the main image pickup optical axis R, and the infrared camera 9C is mainly arranged on the branched image pickup optical axes R _{1 to} R ₃ which are arranged and formed in the image pickup unit 11. Lenses L _{1 to} L ₃ for focusing on a position F ₂ on the imaging optical axis R
Are installed respectively.

It should be noted that when the tester probe 7 is located above the wafer 3 at a distance, the wafer 3 can be viewed by one camera.
The depth of field is designed to be shallow so that the circuit pattern and the tester electrode 6 of the tester probe 7 are not imaged at the same time.

Further, each of the cameras 9A to 9C measures the positional deviation amount between the circuit electrode 5 and the tester electrode 6 by comparing the respective image data and feeds back so that the positional deviation amount becomes zero. Table 4 while controlling
It is connected to a controller 12 that moves the tester probe 7 relative to.

The above is the wafer inspection apparatus according to the present invention. Next, an inspection method using the same will be described. First, when the wafer 3 is carried in and fixed to the table 4 by suction, and imaged by the infrared camera 9A for wafer imaging having a low imaging magnification, infrared rays penetrate the wafer 3 formed of a silicon substrate, and a large number of IC chips 2 ... The circuit pattern of is displayed.

Hundreds of IC chips 2 formed on the wafer 3
Since the inspection order is predetermined, the IC chip 2 in the inspection order 1 is searched for while comparing the image data of the infrared camera 9A with the CAD data of the circuit pattern, and the infrared image pickup device 8 is located directly below the IC chip 2. Stop. At this time, since it is not necessary to position the infrared imaging device 8 in a fixed place on the order of micron order or submicron order, positioning can be performed in a short time.

Then, while maintaining the clearance between the tester probe 7 and the wafer 3, the tester probe 7 is positioned in the XY directions so as to coincide with the XY coordinates of the main imaging optical axis R of the infrared imaging device 8. Also in this case, rough positioning is sufficient and it is not necessary to perform positioning on the order of micron or sub-micron, so that positioning can be performed in a short time.

That is, in the steps up to this point, the infrared image pickup device 8 and the tester probe 7 are only roughly positioned so as to be located directly below and above the IC chip 2 to be inspected, and the positions of the two are mutually aligned. No confirmation required.

Then, the infrared imaging device 8 is fixed at this position, and the circuit pattern of the one IC chip 2 to be inspected and the tester are tested by the infrared camera 9B for wafer imaging and the infrared camera 9C for imaging the tester electrode having a high imaging magnification. Probe 7
The tester electrode 6 is imaged at the same size.

At this time, since the depth of field of each of the infrared cameras 9B and 9C is set to be shallow, the wafer camera infrared camera 9B captures an image of the tester electrode 6 or the tester electrode infrared camera 9C captures an IC chip. The circuit pattern 2 is not imaged.

Therefore, by comparing the respective image data, it is possible to measure the positional deviation amount between the circuit electrode 5 and the tester electrode 6, and the positional deviation amount becomes 0, and the corresponding electrodes 5, 6 respectively. The tester probe 7 is moved while performing feedback control so that the electrodes overlap with each other. At this time, the electrodes 5 and 6 are positioned for the first time on the order of microns or submicrons.

During this time, accurate measurement is sufficient for one time, so that it is possible to perform an inspection in an extremely short time, and it is possible to directly detect whether or not the electrodes 5 and 6 are overlapped with each other. It never happens.

In this way, if the tester probe 7 is lowered in the Z direction by a predetermined clearance while the circuit electrodes 5 and the tester electrodes 6 are accurately positioned, all the tester electrodes 6 will be included in the circuit electrodes. 5 can be simultaneously contacted, and a predetermined motion inspection can be performed.

Moreover, when the tester electrode 6 comes into contact with the circuit electrode 5, the contact state of both electrodes 5, 6 can be imaged by the wafer imaging infrared camera 9B having a high imaging magnification. It is also possible to confirm whether or not they are in contact.

FIG. 2 shows another embodiment of the wafer inspection apparatus. In this example, the wafer inspection apparatus according to the invention of claim 4 is shown, and the infrared imaging apparatus according to the invention of claim 7 is used. . The same parts as those in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted.

The wafer inspection device 21 of this example is the same as the wafer inspection device of FIG. 1 except for the infrared imaging device 22.
Infrared imaging apparatus 22 of the present example, the low imaging magnification and high imaging magnification of the two infrared cameras 9D to focus at the same point, provided with a 9E, the respective infrared camera 9D, 9E imaging optical axis R _{4 of,} R An optical system 23 for branching and forming ₅ from one main imaging optical axis R is provided, and is arranged so as to be movable relative to the table 4 in the XYZ directions with the main imaging optical axis R as the Z direction. Further, lenses L ₄ and L _{5 for} focusing the infrared cameras 9D and 9E at the same point are provided on the branched imaging optical axes R ₄ and R ₅ , respectively.

When performing a wafer inspection using this wafer inspection device 21, after setting the position of the infrared imaging device 8 in the Z direction so that the circuit surface of the wafer 3 fixed to the table 4 is in focus, low imaging is performed. When an image is taken by the infrared camera 9D having a magnification, infrared rays pass through the wafer 3 formed of a silicon substrate, and the circuit patterns of a large number of IC chips 2 ... Are projected.

Based on this image data, I of the inspection order No. 1
The C chip 2 is searched for, and the infrared imaging device 22 is located just below it.
Is roughly positioned, an infrared camera 9E having a high imaging magnification images a circuit pattern of one IC chip 2 to be inspected, and the image is stored.

Next, while maintaining the clearance between the tester probe 7 and the wafer 3, the tester probe 7 is roughly positioned so as to match the XY coordinates of the main imaging optical axis R of the infrared imaging device 22, and at the same time, the infrared imaging device. Two
2 is moved in the Z direction so as to focus at the position of the tester electrode 6 of the tester probe 7.

In this state, the infrared camera 9 having a high imaging magnification
An image of the tester electrode 6 of the tester probe 7 is picked up by E, and the positional deviation amount between the circuit electrode 5 of the IC chip 2 and the tester electrode 6 of the tester probe 7 is determined based on the image and the image data of the previously stored circuit pattern. The tester probe 7 is moved while performing feedback control so that the amount of positional deviation becomes 0 and the corresponding electrodes 5 and 6 overlap each other, and the electrodes 5 and 6 are positioned on the order of microns or submicrons. If so, the subsequent steps are similar to those of the wafer inspection apparatus of FIG.

Incidentally, instead of the infrared image pickup device 22 having two infrared cameras 9D and 9E for low-magnification image pickup and high-magnification image pickup, as shown in FIG. The circuit electrode 5 and the tester electrode 6 are individually imaged using the infrared imaging device 25 provided with one infrared camera 9H provided with a lens (not shown), and the circuit electrode 5 and the tester probe 7 are imaged from the image. The amount of displacement with the tester electrode 6 may be measured. Further, in any case, if the depth of field of the infrared camera is deep, the circuit electrode 5 and the tester electrode 6 can be imaged at the same time without moving in the Z direction.

Further, another embodiment similarly shown in FIG. 2 shows a wafer inspection apparatus according to the invention of claim 5, and uses the infrared imaging apparatus according to the invention of claim 8.

The wafer inspection apparatus 31 of this example also uses infrared imaging.
The wafer inspection apparatus is the same as the wafer inspection apparatus in FIG. 1 except for the apparatus 32.
The infrared imaging device 32 of this example is fixed to the table 4.
Position F corresponding to the circuit surface of wafer 3₁Wafer to focus on
Infrared camera for image pickup 9F and above the wafer 3
Position F corresponding to the tester electrode 6 of the tester probe 7
_TwoEquipped with infrared camera 9G for imaging tester electrode
And the image pickup optical axis R of each infrared camera 9F, 9G₆,
R₇Optical system 33 for branching and forming an optical axis R from one main imaging optical axis R
Is equipped with. In addition, each of the branched imaging optical axes R₆, R₇
Infrared cameras 9F and 9G are mounted on the circuit surface of the wafer 3 and
Lens L for focusing with the tester electrode 6 of the tester probe 7
₆, L ₇Are installed respectively.

Each of the image pickup cameras 9F and 9G has a main image pickup optical axis R.
A low imaging magnification of 0.8 to 2.5 times, which is convenient for positioning, and a high imaging magnification of 10 to 18 times, which is convenient for accurately detecting the positional deviation of the electrodes 5 and 6 ( It is designed to be about 5 to 8 times), and both functions are combined in one camera.

When performing a wafer inspection using this wafer inspection apparatus 31, first, the circuit pattern of the wafer 3 fixed to the table 4 is imaged by the wafer imaging infrared camera 9F and the IC chip 2 of the inspection order 1 is taken. Is searched for, and the infrared imaging device 32 is stopped immediately below.

Next, while maintaining the clearance between the tester probe 7 and the wafer 3, the tester probe 7 is positioned so as to coincide with the XY coordinates of the main imaging optical axis R of the infrared imaging device 32.

The infrared camera 9 for imaging the tester electrode
By imaging the tester electrode 6 of the tester probe 7 with G and comparing the image data of the cameras 9F and 9G, I
While measuring the positional deviation amount between the circuit electrode 5 of the C chip 2 and the tester electrode 6 of the tester probe 7, feedback control is performed so that the positional deviation amount becomes 0 and the corresponding electrodes 5 and 6 overlap. If the tester probe 7 is moved and the electrodes 5 and 6 are positioned on the order of microns to submicrons, the subsequent steps are the same as those of the wafer inspection apparatus of FIG.

It should be noted that instead of the infrared imaging device 32 equipped with the two infrared cameras 9F and 9G for wafer imaging and tester electrode imaging, as shown in FIG. 3, one infrared imaging device having a relatively deep depth of field is used. Infrared imaging device 3 including infrared camera 9H
5, the circuit electrode 5 and the tester electrode 6 may be simultaneously imaged, and the positional deviation amount between the circuit electrode 5 and the tester electrode 6 of the tester probe 7 may be measured from the image.

In each of the above explanations, the case where the circuit electrode 5 and the tester electrode 6 are imaged has been described.
The present invention is not limited to this, and an image of an arbitrary marker formed on each IC chip 2 and an arbitrary marker formed on the tester probe 7 is imaged, and the electrodes 5 and 6 are set based on the preset positional relationship between them. The positions may be controlled so that they overlap each other.

[0055]

As described above, according to the present invention, it is possible to simultaneously image the tester electrode and the circuit electrode of the tester probe while the infrared imaging device is roughly positioned right under the IC chip to be inspected. Therefore, not only can each electrode be positioned on the micron to sub-micron order based on the image data, but there is no need for tedious inspection preparation work or confirmation of the position of each optical system. In addition, since the positioning can be performed accurately, there is a very excellent effect that the inspection time can be shortened.

Moreover, since the infrared image pickup device arranged below the wafer can pick up the image of the circuit pattern formed on the upper surface thereof and the tester probe arranged above it, the image pickup device is placed between the wafer and the tester probe. Since it is not necessary to arrange the device, the clearance can be minimized and the device can be miniaturized, and at the same time, since the moving distance is shortened, there is also a very excellent effect that the device is less prone to error and deviation.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a wafer inspection apparatus according to the present invention.

FIG. 2 is an explanatory diagram showing another embodiment.

FIG. 3 is an explanatory diagram showing another embodiment.

FIG. 4 is an explanatory view showing a conventional device.

[Explanation of symbols]

1, 21, 31, 24, 34 ... Wafer inspection device 2 ... IC chip 3 ... Wafer 4 ... Table 5 ... Circuit electrode 6 ... Tester electrode 7 ... Tester probe 8 , 22, 25, 32, 35 ... Infrared imaging devices 9A to 9H ... Infrared camera R ... Main imaging optical axis R _{1 to} R ₇ ... Imaging optical axis

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2F065 AA07 AA14 AA20 BB02 BB18                       CC19 DD06 FF04 FF61 FF67                       GG22 JJ03 JJ05 JJ09 JJ26                       LL00 LL12 PP04 PP12 QQ24                       QQ31 QQ38 TT02 TT08                 2G065 AA11 AB02 AB23 BA14 BA40                       BB06 BB14 BB44 BB48 BD03                       CA11 DA18 DA20                 4M106 AA01 BA01 DD13

Claims (8)

[Claims] 1. A wafer (3) having a large number of IC chips (2) formed thereon is fixed with its circuit surface facing upward, and is simultaneously contacted with a circuit electrode (5) of one IC chip (2). A tester probe (7) having a large number of tester electrodes (6) is provided with an arbitrary IC chip (2) so that the electrodes (5, 7) overlap each other.
In the wafer inspection method in which the tester probe (7) is lowered and the electrodes (5, 7) are brought into contact with each other and the circuit is sequentially inspected for good or bad of each IC chip (2) after being positioned directly above When positioning the tester probe (7) directly above an arbitrary IC chip (2), a circuit pattern image of the wafer (3) and an image of the tester probe taken by an infrared camera from below the wafer (3) are displayed. On the basis of circuit electrodes (5)
A wafer inspection method, wherein the tester probe (7) is relatively moved to a position where the tester electrode (6) and the tester electrode (6) overlap each other. 2. A circuit electrode (5) of one IC chip (2) is attached to a table (4) on which a wafer (3) having a large number of IC chips (2) formed thereon is fixed with its circuit surface facing upward. )
A tester probe (7) having a large number of tester electrodes (6) that are simultaneously contacted with the substrate in the XYZ directions based on the image of the circuit pattern formed on the circuit surface of the wafer (3) and the image of the tester probe. A wafer inspecting device for moving and bringing the electrodes (5, 7) into contact with each other to inspect whether a circuit is good or bad, wherein the table (4) is made of an infrared transmissive material, and the table (4). From below the wafer (3)
The infrared image pickup device (8, 22, 32) for picking up the circuit pattern formed on the circuit surface and the tester probe (7) is arranged so as to be movable at least in the XY directions with respect to the table (4). Wafer inspection device. 3. An infrared camera for imaging two wafers having a low imaging magnification and a high imaging magnification, in which the infrared imaging device (8) focuses on a circuit surface of a wafer (3) fixed to a table (4). 9A, 9B) and a tester electrode (6) of a tester probe (7) located above the wafer (3) are in focus, and the infrared imaging camera (9B) for wafer imaging has an imaging magnification of the high imaging magnification. In addition to the infrared camera (9C) for imaging the tester electrode,
The wafer inspection apparatus according to claim 2, further comprising an optical system (10) for branching and forming the imaging optical axes (R _{1 to} R ₃ ) of A to 9C from one main imaging optical axis (R). 4. The infrared imaging device (22) comprises two infrared cameras (9D, 9E) having a low imaging magnification and a high imaging magnification for focusing at the same point, and the infrared cameras (9D, 9E). ) Is provided with an optical system (23) for branching and forming the imaging optical axis (R ₄ , R ₅ ) from one main imaging optical axis (R),
The wafer inspection apparatus according to claim 2, wherein the wafer inspection apparatus is arranged so as to be relatively movable in the Z direction along the main imaging optical axis (R). 5. An infrared camera (9F) for imaging a wafer, wherein the infrared imaging device (32) focuses on a circuit surface of a wafer (3) fixed to a table (4), and the wafer (3).
Infrared camera for imaging the tester electrode (9) focused by the tester electrode (6) of the tester probe (7) located above
G) and the infrared cameras (9F, 9F)
The wafer inspection apparatus according to claim 2, further comprising an optical system (33) for branching and forming the image pickup optical axes (R ₆ , R ₇ ) of G) from one main image pickup optical axis (R). 6. An infrared camera (9A, 9B) having a low imaging magnification and a high imaging magnification for focusing at the same point, and the respective cameras (9A, 9B) have different focal points and the high imaging. The infrared camera (9B) having a magnification is provided with an infrared camera (9C) having the same imaging magnification, and the imaging optical axes (R _{1 to} R ₃ ) of the infrared cameras (9A to 9C) are connected to one main imaging optical axis ( An infrared imaging device comprising an optical system (10) branched from R). 7. Infrared cameras (9D, 9E) having a low imaging magnification and a high imaging magnification for focusing at the same point are provided, and an imaging optical axis (R) of each infrared camera (9D, 9E).
_4. An infrared imaging device comprising an optical system (23) for branching and forming ( ₄ , R ₅ ) from one main imaging optical axis (R). 8. Two infrared cameras having different focal points (9)
F, 9G), and each infrared camera (9
F, infrared imaging apparatus characterized by comprising an optical system (33) for imaging light axis (R _{6, R 7)} for branching from one of the main imaging optical axis (R) of 9G).