JPS6235212A - Observing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an observation device used in a wafer inspection device for inspecting semiconductor wafers.

[Background of the invention]

For example, wafer inspection equipment typically uses one stage to inspect semiconductor wafers one by one;
Currently, clean rooms and the like of factories that produce C and other products take up a considerable amount of space.

Therefore, recently, inspection apparatuses having multiple stages (for example, two) have been proposed, which are thought to save space compared to conventional apparatuses.

In addition, in the wafer inspection equipment, there is a process called needle alignment in which the probe bottle is brought into contact with the IC batt of UNO.In this process, the worker visually observes the probe using the microscope attached to the UNO inspection equipment. work is being carried out. Although efforts have recently been made to automate this process, the task of visually checking the actual contact between the IC bat and the probe bottle will continue to be necessary.

However, when there are multiple stages, it is not necessarily necessary to provide a microscope or the like for each stage. In other words, if an observation means such as a microscope is provided for each stage, the significance of providing a plurality of stages in one wafer inspection apparatus will be reduced.

[Purpose of the invention]

The present invention has been made in view of the above, and an object of the present invention is to provide an observation device that is suitable for a wafer inspection device having a plurality of stages, has an easy-to-use structure, and is advantageous for work and maintenance. It is something.

[Summary of the invention]

The present invention includes one observation means including an optical system, for example, a microscope, which is moved to an observation position of any observation target by a moving means, and the microscope is rotated about the optical axis of the optical system by a rotating means. make it possible,
The technical point is that two or more observation objects can be observed using one observation means.

〔Example〕

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

FIG. 1 shows a plan view of an embodiment of a wafer inspection apparatus having an observation apparatus according to the present invention.

In addition, FIG. 2 shows a front view of the inside of the casing, particularly the stage part, and FIG. 6 shows the loading mechanism part of the cross section taken along line A-A in FIG. ing.

In FIGS. 1 to 6, 1 is a pedestal, and 2 and 6 are vibration isolation mechanisms provided on the pedestal 1, respectively. The base 4 is fixed on the vibration isolation mechanism 2. The XY stage 5 is provided on the base 4 and is movable on the base 4 in the X and Y directions.The 02 stage 6 is provided on the XY stage 5 and is movable on the XY stage in the Z direction.

The θ rotation stage 7 is provided on the 2 stages 6 and can rotate (rotate) on the Z stage 6.
Z and θ) are each driven by a motor (not shown). The wafer 8 is placed on the θ rotation stage 7. The θ rotation stage 7 has a suction mechanism (not shown),
The suction mechanism allows the wafer 8 to be vacuum suctioned onto the surface.

The probe card 9 is a support stand 1 that stands up from the base 4.
Fixed to 0. The wafer 8 is mounted on the above-mentioned XY stage 5,
x by the z stage 6 (fine movement) and the θ rotation stage 7,
Alignment in y, z, and θ directions is controlled. Reference numeral 13 denotes a sensor (light receiving section) that detects the position of a chip formed on the wafer 8 in order to align the wafer 8 as described above. The IC chips formed on the wafer 8 are brought into contact with the probe needles 9a by vertical movement (coarse movement) of the Z stage B. The signal obtained by the probe needle 9a is transferred to the probe card 9.
The signal is then inputted to a tester provided separately from the wafer inspection apparatus, and an inspection output regarding the wafer 8 is obtained by the tester. Of course, the tester may be provided integrally with the wafer inspection apparatus described above. In this example, the above-mentioned elements 4-
7.9 to 11.13 constitute the right inspection section.

The base 14, XY stage 15, Z stage 16, θ rotation stage 17, probe card 19, support stand 20, and sensor 22 are elements 4 to 7.9 to 11 of the right inspection section, respectively.
．． 13, and constitutes the p1 left inspection section. 18 indicates a wafer placed on the θ rotation stage. The above-mentioned right side inspection section and left side inspection section are each supported by a vibration isolation mechanism 2.6 provided independently on the pedestal section 1, and the vibration isolation mechanism 2.6 prevents mutual vibration. It is configured so that it is not transmitted. The control unit 23 includes a microcomputer (hereinafter referred to as MCU) 23a consisting of an arithmetic processing section, a part of memory, a processing section 10, etc., and controls the stages 5 to 7, 15 to 17 described above, the wafer carrier transport mechanism described below, Controls the driving of a wafer loading mechanism, etc., which will be described later.

Next, behind the center of the plane of the inspection device, there is provided a vibration mechanism 21 which can be oscillated around a central axis 21B, and a microscope is installed at the tip of the arm 21A as an observation means. 11 are provided.

The microscope 11 is rotatable relative to the tip of the arm 21A within a plane of movement about the optical axis of the objective lens 11A (see FIG. 2), which is parallel to the central axis 21B. This allows the eyepiece 11B of the microscope 11 to face forward even if the p1 arm 21A rotates.

That is, the microscope 11 is configured to be able to revolve around the central axis 21B and to be able to rotate around the optical axis of the objective lens 11A.

Next, the wafer carrier transport mechanism and wafer loading mechanism will be described. The wafer carrier transport mechanism is the first
The sea urchin loading mechanism is located at a portion indicated by 61 in the figure, and the sea urchin loading mechanism is disposed at a section indicated by 62 in FIG. The wafer carriers 33g and 33b containing a plurality of wafers are sequentially transported to position B by a transport mechanism (not shown). The carrier 33a brought to position B is placed on the mounting table 3 shown in FIG.
4aK is loaded and raised by the elevator 64 to the position shown by the broken line. A motor 65 shown in FIG. 6 is used to move the mounting table 34a' of the elevator 34 up and down. This elevator 6
4 and the motor 65 constitute a part of the above-mentioned transport mechanism. The support stand 36 fixed to the pedestal part 1 has a guide member 67 and a worm 38, and the worm 68 is connected to the motor 6.
Rotated by 9. The motor 40 has a worm gear (not shown) that meshes with the worm 38, and is guided by the guide member 37 by the forward and reverse rotation of the motor 39, so that the force direction (left and right in FIG. 6) is
X direction). The seventh wheel 40 has a rotating shaft 41,
The arm 42 is fixed to this rotating shaft 41. The arm 42 can be rotated clockwise and counterclockwise in FIG. 1 about the rotating shaft 41 by forward and reverse rotation of the motor 40. In this embodiment, the nine elements 66 to 42 described above constitute the wafer loading mechanism 'fr. The support stand 4 is fixed to the pedestal part 1, and the motor 44 is fixed to this support stand 43. A stage 45 for pre-aligning the wafer can be rotated (rotated) by a motor 44.

Next, the operation of this device will be explained using FIG. 4 as a valve plate.

First, in response to a command from the 84 CU (23+a) in the control unit 26, the transport mechanism is activated by the carriers 33a and 3 as described above.
3b is brought to the 3rd position one after another, and the carrier at position B is lifted up and down @64 to the position shown by the broken line in Figure 3. M.C.
U 23 a determines whether there is a wafer on the θ rotation stage 7 or not. When it is determined that there is no wafer on the stage 7, it is determined whether or not there is a wafer on the pre-alignment stage 45. And on stage 45, Uni/S
If it is determined that there is no wafer, a command is issued to bring the wafer to the pre-alignment stage 45. And M
The loading mechanism and the prealignment stage operate as follows according to the subroutine (not shown) of the CU 23a. First, the motor 69 rotates forward and the motor 40 moves to the left in FIG. Then, one of the wafers stored in the carrier 53a is placed on the arm 42. Then, the motor 9 begins to rotate in reverse, and the arm 42 together with the motor 40 moves further to the right in FIG. 3 through the positions shown in FIGS. 1 and 3. The motor 40 is then stopped from moving at an appropriate position. After that, the motor 40 starts rotating, and the arm 42 rotates around the shaft 41 at 18
Rotate 0 degrees. In this way, the wafer 1 is brought onto the pre-alignment stage 45, and the wafer is placed on the stage 45. Thereafter, the motor 40 moves to the left in FIG. 3 due to the rotation of the motor 39, and returns to the next position shown in FIGS. 1 and 6. However, the arm 42 remains facing the stage 45. On the other hand, the stage 45 on which the evaporator is placed performs pre-alignment of the wafer by rotation.

When the MCU 23a detects that the pre-alignment has been completed, it issues a command to set the wafer on the 0-rotation stage 7; If it is determined that there is a wafer on the stage 45 at step (2) and the pre-alignment has already been completed, the process immediately moves to step (2). Further, if it is determined that there is a wafer on the stage 45 at stage (2), and the pre-alignment has not yet been completed at that time, the pre-alignment operation continues, and when the pre-alignment is completed, the process moves to stage (2). At step (3), the command to set the wafer on the θ rotation stage 7 is issued, and the MCU 23
According to the subroutine a (not shown), the loading mechanism and the fine alignment stage (XY, Z, θ stages 5 to 7) operate as follows. First, the motor 69 begins to rotate in reverse, and the motor 40 moves to the right in FIG. 6 while keeping the arm 42 facing the prealignment stage 45. When the pre-aligned wafer is placed on the arm 42, the motor 39 rotates forward, and the motor 40 moves to the left in FIG.

Motor 40 then returns to the position shown in FIGS. 1 and 6. Thereafter, the motor 40 rotates forward, and the arm 42 rotates 90 degrees clockwise in FIG. The wafer is thus brought to position C.

At this time, the XY stage 5 is driven by a motor (not shown), and the θ rotation stage 7 has also moved to the C position. Therefore, the wafer is placed on the θ rotation stage Z. The stage 7 attracts this wafer and fixes it on the surface. In this way, the wafer is set on stage Z. Thereafter, the arm 42 is rotated 90 degrees clockwise in FIG. 1 by the forward rotation of the motor 40.
degree and return to the state shown in Figure 1. Also, θ rotation stage 7
By moving the XY stage 5, it returns to the position shown in FIGS. 1 and 2. Thereafter, the MCU 23a drives the XY stage in the X and Y directions, causes an illumination optical system (not shown) to illuminate the wafer, and causes the sensor 16 to receive reflected light from the wafer. In this manner, information regarding the positions of chips formed on the wafer is obtained. MCU 23 a is
The stages 5 to 7 are slightly moved based on the data obtained by the sensor 13, and fine alignment of the wafer is performed. Wafer 8 in FIG. 1 is a wafer produced in this manner. When the fine alignment of the MCU23aH wafer 8 is completed, a signal is sent to a tester (not shown).
At the same time, the two stages 6 are driven by a motor (not shown) to
The rotation stage 7 is raised.

As the θ rotation stage rises, the tips formed on the wafer 8 come into contact with the probe needles 9a.

At this time, the operator moves the microscope 11 as indicated by the broken line in FIG. 1 or 2 to observe the state of contact between the tip and the blog needle 9a.

Next, the tube needle 9a is brought into contact with the tester and a nine-step test is performed. Once the chip has been inspected,
The z stage 6 is driven by the signal from the MCU 23a, and the θ rotation stage 7 is lowered. After the XY stage 5 is moved by one chip, the θ rotation stage 7 is moved again.
is raised and the next chip comes into contact with the probe needle 9a, and is inspected by the tester. Such actions are repeated one after another]
As the wafer 8 is returned, a large number of chips formed on the wafer 8 are inspected. When the MCU 23a issues the wafer set command (2), the MCU 23a immediately moves to the step (2) without waiting for the above-mentioned wafer inspection to be completed, and determines whether or not there is a wafer on the θ rotation stage 17. That is, as mentioned above,
The steps of wafer setting, fine alignment, and wafer inspection are performed in parallel with the determination (1) (and subsequent steps). At stage ■, θ rotation stage 7
If it is determined that there is a wafer in M CU 23 a
■ It is determined whether the inspection of the wafer on the θ rotation stage Z has been completed. If the wafer 1 inspection has not yet been completed at that time, the MCU 23a continues the above-described wafer setting on the stage 7, fine alignment of the wafer, and wafer inspection. Then, without waiting for the end of the wafer inspection, the process immediately shifts to step (3). That is, the steps of wafer setting, fine alignment, and wafer inspection, and the determination (and subsequent steps) are performed in parallel. If the inspection of the wafer has been completed at stage (2), the MCU 23a issues a command (2) to return the wafer on the θ rotation stage 7 to the carrier 33a. When this command is issued, the loading mechanism and the fine alignment stage operate as follows according to a subroutine (not shown) of the MCU 23a. First, the motor 40 rotates in the reverse direction, and the arm 42 rotates 90 degrees counterclockwise from the position shown in FIG.

At the same time, the XY stage 5 is driven, and the θ rotation stage 7F
Moved to iC position. Then, the vacuum suction is released and the wafer 8 is placed on the arm 42.

Thereafter, the stage 7 is moved to the position shown in FIG. Note that the stage 7 may be provided so as to wait at position C until the next wafer arrives. After the Eva 8 is placed on the arm 42, the motor 4o rotates forward, and the arm 42 rotates 90 degrees clockwise in FIG. 1 to return to the position shown in FIG. 1. Then, the motor 69 rotates forward. The motor 40 is moved to the left in FIG. 6, and the wafer is returned into the wafer carrier 33a. Thereafter, the motor 39 returns the Q motor 40 to the position shown in FIG. When the motor 40 completes returning to this position, MCU
23 a will return to the stage ■.

When the MCU 23 a shifts to stage 2 or from stage 2 to stage 2, it is determined whether or not there is a wafer on the θ rotation stage 17 . If it is determined that there is no wafer on the stage 17, it is determined (2) whether or not there is a wafer on the pre-alignment stage 45. If it is determined that there is no wafer on the stage 45, ■Pre-alignment stage 4
I give the command to bring 5 wafers. Then, in the same manner as the operation in step (2), the wafer stored in the carrier 33a is brought to the pre-alignment stage 45, and pre-alignment of the wafer is performed. When it is detected that the pre-alignment is completed in this way, a command is issued to set the wafer on the θ rotation stage 17 of [Co., Ltd.]. The operation when it is determined that there is a wafer on the stage 45 at step (2) is the same as the operation when it is determined that there is a wafer on the stage 45 at step (2). When a command is issued to set the wafer on the θ rotation stage 17 at step (3), the MCU 23
a controls the loading mechanism and stages 15 to 17 according to a subroutine not shown. This is done in the same manner as the control for setting the wafer on the stage 45 onto the stage 7, the control for fine alignment of the set wafer, and the control for wafer inspection in step (2). However, ■ means the direction of the rotational force of arm 42, the point that stages 15 to 17 are moved instead of stages 5 to 7, and the point that stay i:/17 is brought to the θ position when setting the wafer on stage 17. , the wafer on stage 17 is probe needle 1
The points inspected in 9a are different.

In this case, the operator moves the microscope 11 as shown by the solid line in FIG. 1 or 2 to observe and check the state of contact between the chips on the wafer and the probe needles 19.

After this check, the chip is inspected. Incidentally, the wafer inspection is performed by the same tester as described above. When the MCU 23a issues the @ wafer set command, it immediately shifts to the VCo stage without waiting for the wafer inspection to be completed, and determines whether or not there is a wafer on the pre-alignment stage 45. become. That is, as in (7) above, the steps of setting the wafer on the stage, fine alignment of the set wafer, and inspecting the wafer, and the determination (and subsequent steps) in (2) are performed in parallel. When it is determined that there is a wafer on the pre-alignment stage 45 at step (2), the MC023a determines whether or not the inspection of the wafer on the eaves table 17 has been completed for the 00th time. If the wafer inspection has not been completed by that time, s M CU 25 a
Step 0 continues setting the wafer on stage 17, fine alignment of the wafer, and inspecting the wafer. Then, without waiting for the completion of the wafer inspection, the process immediately moves to step 0. That is, similar to the above-mentioned O1, the wafer setting, fine alignment, and wafer inspection processes and the O discrimination (and subsequent processes) are performed in parallel.

If the wafer inspection is completed at stage 0, MCU23a
issues a command to return the wafer on the @θ rotation stage 17 to the carrier 33a. When this command is issued, MCU23
The loading mechanism and stages 15 to 17 for fine alignment operate according to the subroutine (not shown) in step a, and the wafer 18 on the stage 17 is returned to the carrier 33a in the same manner as in step 6), and as shown in FIGS. State is restored. However, ■ means the direction of the rotational force of the arm 42, the point in which stages 15 to 17 are moved, and stage 17! >;The points brought to the D position are different. MCU 23
When the loading mechanism is restored to the state shown in FIGS. 1 and 3, step (a) returns to step (2). When the MCU 23a shifts from @ or O to the 00 stage, it determines whether or not there is a wafer on the pre-alignment stage 45. If it is determined that there is no wafer on stage 45, a command is issued to bring the wafer to stage 45 for zero prealignment. Then, according to the subroutine of the MCU 25a, the carrier 33 is
The wafer stored in a is placed on the pre-alignment stage 4.
5 and performs pre-alignment of the wafer.

When the MCU 23a completes the pre-alignment of the wafer according to the [phase] command, it returns to the ω stage. In addition, the operation when it is determined that there is a wafer on the stage 45 at stage 00 is as follows.
The operation is similar to the operation when it is determined that there is a wafer on the stage 45 at step 2.8.

Just 1. McU23& returns to ■ upon completion of pre-alignment.

In this embodiment, a command with a loading mechanism (first
When another command (second command) is issued to operate the loading mechanism (for example, when the command ■ and the command ■ are issued), the loading mechanism operates according to the first command. Needless to say, the operation according to the second command is performed after the operation according to the second command is completed. However, the time from when a wafer is set on the θ rotation stage 7° 17 until the inspection of that wafer is completed is much longer than the time required for the loading mechanism to operate. Therefore, the two commands described above are rarely applied to the loading mechanism at the same time.

In addition, in this example, ■, 0. The determinations of (1), (2), and 0.0.0 are made by the MCU 23a itself determining the control states of the loading mechanism, prealignment stage, fine alignment stage, etc. according to the flowchart in FIG. For example, when determining ■, the procedure is as follows. That is, if the arm 42 has finished receiving and taking the wafer from the θ rotation stage 7 and the operation of supplying a new wafer from the arm 42 to the stage 7 has not been performed, the MCU 23a will not transfer the wafer to the θ rotation stage 7. It is determined that there is no wafer.

In addition, each motor and stage 5 of 55, 39, 40, and 44
~7. Each motor (not shown) that moves 15 to 17 is an MC
Needless to say, it is driven by a signal transmitted from U23a via a driver (not shown).

Further, when the wafer carrier has finished inspecting all of the large number of wafers stored therein, the wafer carrier is moved away from the B position by the transport mechanism, and the next new wafer carrier is brought to the B position. Then, operations such as loading, prealignment, wafer setting, fine alignment, wafer inspection, etc. are repeated as described above.

As described above, in this embodiment, while the wafer is being inspected by the single inspection unit (while the operation based on the command of ■ or ■ is being carried out), the wafer is loaded into the independent inspection unit and inspected. -@Alui is the operation in stages ① to ①], one microscope 11 is moved and used in common.

In addition, in the example, from ■ to ■ of the brooch yard, ■
In the above example, the M CU 23 a may be provided so as to transition from ■ to ■ or from ■ to ■.

In addition, if electromagnetic shielding members 46 and 47 are provided between the left and right inspection sections as shown by broken lines in Fig. 2, the electromagnetic noise generated in the force inspection section will be affected by the other force inspection section. The impact can be reduced. Therefore, if the influence of electromagnetic noise is large, it is desirable to provide an electromagnetic shielding member as described above.

Further, in the above embodiment, the observation device according to the present invention is applied to a wafer inspection device, but the present invention is not limited to this in any way, and can be applied to other devices as well. It is.

Furthermore, similar effects can be obtained by using a television camera or the like in addition to a microscope as the observation means.

(Effects of the Invention) - As explained above, according to the present invention, there are effects of a simple configuration, easy work and maintenance, and good operability.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an example of a wafer inspection device equipped with an embodiment of the viewing device according to the present invention, FIG. 2 is a front view showing the stage portion inside the casing, and FIG. FIG. 4 is a sectional view showing the loading mechanism portion of the device along A-Aiiiilj, and is a flowchart showing the operation of the control device. (Explanation of symbols of main parts) 5 to 7...Stage mechanism, 11...Microscope, 1
5 to 17...Stage mechanism, 21...1] mechanism, 21A...Arm, 66 to 42...Loading mechanism. Agent Patent Attorney Tadashi Sato Figure 7

Claims (3)

[Claims] (1) An observation device for observing at least two observation objects, including one observation means including an objective optical system, and a swinging means for supporting the observation means so as to be able to swing between the respective observation objects; An observation device comprising means for rotating the observation means about an optical axis of the objective optical system that is parallel to a central axis of swing of the swing means. (2) Claim 1, wherein the observation means is a microscope.
Observation device described in section. (3) The observation device according to claim 1, wherein the observation means is a television camera.