JP2002214072A - Light irradiation device and inspection device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the inspection time of the solid-state image pickup element formed on the surface of a wafer. SOLUTION: Two solid-state image pickup element 2a and 2b arranged in close vicinity of the surface of a wafer 1 are irradiated with inspection lights respectively having uniform luminous intensities from the ends 14a and 14b divided into two of an optical fiber. Shutters 16a and 16b are provided in opposed relation to the ends 14a and 14b of the optical fiber, and the solid-state image pickup elements 2a and 2b are separately irradiated with inspection lights by controlling the on-off operation of the shutters 16a and 16b to be inspected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light irradiating apparatus for performing control of irradiating a test object with light and an inspection apparatus using the light irradiating apparatus.

[0002]

2. Description of the Related Art Solid-state imaging devices (semiconductor imaging devices) used in digital cameras and the like, for example, CCDs (Charge Couplers).
d Device: charge-coupled device)
A semiconductor integrated circuit is formed by lamination by a VD, a photolithography process, or the like. Generally, a large number of solid-state imaging devices are formed on a single wafer surface in a matrix. Each solid-state image sensor thus produced is
A performance test of the solid-state imaging device is performed in a state where the solid-state imaging device is aligned and formed on the wafer, and the solid-state imaging devices that pass here are individually cut and used for a digital camera or the like.

An inspection apparatus for performing an inspection in a state where the solid-state imaging devices are aligned on a wafer as described above generally includes a light irradiation device, a prober, and a tester. The prober has a stage for moving the wafer and a probe pin for energizing the wafer. Then, the wafer is placed on the stage, the solid-state image sensor to be inspected is moved to the position of the probe pin, and the probe pin is brought into contact with the output terminal of the solid-state image sensor to energize. In this state, the surface of the solid-state imaging device is irradiated with inspection light having high illuminance uniformity by a light irradiation device, and an electric output from an output terminal of the solid-state imaging device at this time is taken in via a probe pin and sent to a tester.
A light irradiation device used for such an inspection is disclosed in, for example, Utility Model Registration No. 2582733.

FIG. 4 shows such a conventional inspection procedure. When the measurement is started from step S51, first, the prober makes sure that the solid-state imaging device to be inspected is located at a position corresponding to the probe pin. The wafer is moved to (step S52), and the probe pin is brought into contact with the output terminal of the solid-state imaging device (device under test) to be inspected to be electrically connected to the tester (step S53). Next, the light irradiation device irradiates the device under test with inspection light (step S54), and the tester takes in the electrical output output from the output terminal via the probe pin at this time to perform the inspection (step S55). When the inspection of one device under test is completed in this way, the prober removes the probe pin from the device under test (step S56). Then, returning to step S52, the inspection of the next device to be inspected formed on the wafer is performed in the same procedure as described above (steps S52 to S5).
6). If this inspection is completed for all the devices to be inspected formed on the surface of the wafer, step S57
When it is determined that the inspection is completed, the inspection is terminated.

[0005]

As can be seen from the above description, the conventional inspection is performed on each of the solid-state imaging devices formed on the wafer surface in order, and the above-described steps S52 to S56 are performed. This has to be repeated for all the devices to be inspected, and there is a problem that the inspection time becomes long. In particular, the mechanical operation control time, such as the movement positioning of the wafer in step S52 and the contact and removal operations of the probe pins in steps S53 and S56, is long, and it is required to shorten it.

The present invention has been made in view of such a problem.
An object of the present invention is to provide a light irradiation device capable of shortening an inspection time and an inspection device using the same.

[0007]

In order to achieve the above object, a light irradiation device according to the present invention comprises a plurality of light irradiation units for irradiating a plurality of test objects with predetermined light. And light blocking means for selectively blocking light irradiation by the plurality of light radiators, and blocking control means for controlling the operation of the light blocking means. Note that the plurality of objects to be inspected include a plurality of solid-state imaging devices formed aligned on a wafer.

The light irradiating device is configured to be capable of irradiating a predetermined light to a plurality of test objects at a time. Irradiation can be switched, and once the positioning of the test object with respect to the light irradiation means (positioning of the wafer) is performed once, inspection of a plurality of test objects irradiated with light by a plurality of light irradiators is performed. The inspection can be performed in the positioning state, the inspection time can be reduced, and the inspection efficiency can be improved.

An inspection apparatus according to the present invention is an inspection apparatus for inspecting an output signal from each of the objects when each of them is connected to a plurality of objects and receives light irradiation. Means for controlling the operation of the light blocking means, and irradiating the corresponding test object with predetermined light from only one of the light irradiation means. The control operation for causing the inspection means to inspect the output signal from the plurality of light irradiators is sequentially performed.

When a plurality of test objects arranged in close proximity are simultaneously irradiated with inspection light from a plurality of light irradiating means, the light from the light irradiating means which should irradiate the adjacent test object for each test object also enters the inspection. There is a problem that accuracy is reduced. However, in the case of the inspection apparatus according to the present invention, only irradiation from one light irradiation unit is performed at a time in a state where it is possible to irradiate the inspection light from the light irradiation unit to each of the plurality of test objects. By doing so, it is possible to perform an accurate test for each test object.

[0011]

Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an inspection apparatus TU using a light irradiation apparatus 10 according to an embodiment of the present invention.
Is shown. This inspection apparatus TU is a silicon wafer 1
A plurality of solid-state imaging devices 2 aligned on the surface of the device are irradiated with inspection light to inspect their outputs. This inspection device TU
It comprises a light irradiation device 10, a tester 30, and a prober (not shown). The prober can simultaneously contact a transfer holding device (not shown) capable of transferring and moving the wafer 1 in a horizontal plane and both output terminals of two adjacent solid-state imaging devices 2a and 2b formed on the surface of the wafer 1. Probe pins 21. The light irradiation device 10 irradiates inspection light to the surface of the wafer 1 held by the transfer holding device of the prober. The tester 30 receives an electric output from the probe pin 21 of the prober and performs an inspection.

The light irradiation device 10 has a light source 11, and an illuminance adjustment device 12 adjusts the illuminance of light emitted from the light source 11. The illuminance adjustment device 12 adjusts the brightness of the inspection light, and includes an ND filter, a dot filter, and the like. The inspection light having the illuminance adjusted in this way passes through the light uniforming device 13 and the illuminance unevenness is adjusted, so that the inspection light having the uniform illuminance in the light beam is produced. As the light uniforming device 13, a fly array lens, a rod lens, a micro lens array, or the like is used.

The inspection light thus uniformized is incident on the optical fiber 14. The optical fiber 14 has a tip 14
a, 14b are branched into two branches, and the inspection light having uniform illuminance emitted from the light uniforming device 13 is divided into two in the optical fiber 14, and the distal ends 14a, 14 are branched into two branches.
b. These optical fiber tips 1
F value adjusting devices 15a and 15b are provided opposite to 4a and 14b, and each of the inspection lights is adjusted so as to have a predetermined F value. Shutters (light interrupters) 16a and 16b are provided below the F-number adjusting devices 15a and 15b, and these shutters 16a and 16b are opened and closed by shutter controllers (interruption controllers) 17a and 17b, respectively. It can be controlled to block light passing through it.

A wafer 1 transported and positioned by a transporter of a prober (not shown) is held below the shutters 16a and 16b, and the light source 11 is controlled by opening and closing the shutters 16a and 16b as described above. The inspection light generated by adjusting the light from the two solid-state imaging devices 2 located immediately below these shutters 16a and 16b among the solid-state imaging devices 2 formed on the surface of the wafer 1
a, 2b (hereinafter, for the sake of simplicity, two solid-state imaging devices 2 to be inspected are denoted by reference numerals 2 and 3).
a, 2b).

As described above, the inspection light is transmitted to the solid-state imaging devices 2a and 2a.
When irradiating the probe b, the transfer and holding device of the prober positions and holds the solid-state imaging devices 2a and 2b to be inspected so as to be located directly below the shutters 16a and 16b, respectively. The output terminals of the solid-state imaging devices 2a and 2b are contacted and electrically connected. Note that the upper part of the probe pin 21 is open, and the light receiving portions of the solid-state imaging devices 2a and 2b are
The inspection light is received from the light irradiation device 10 through the opening above the first light source 1.

Here, when light is emitted from the light source 11 in a state where both the shutters 16a and 16b are opened, the two inspection lights adjusted as described above and divided by the optical fiber 14 pass through the shutters 16a and 16b. Two solid-state imaging devices 2a and 2b that pass through and are located below
Is irradiated. This state is shown in FIG. 3 (A), and as can be clearly seen from this figure, the left solid-state imaging device 2a has inspection light (emitted from the optical fiber end 14a) that has passed through the shutter 16a located immediately above it. Inspection light), but also partially receives inspection light (inspection light emitted from the optical fiber end 14b) that has passed through the shutter 16b. Similarly, the right solid-state imaging device 2b mainly receives inspection light (inspection light emitted from the optical fiber end 14b) that has passed through the shutter 16b located directly above the solid-state imaging device 2b, but has received inspection light (inspection light that has passed through the shutter 16a). The inspection light emitted from the optical fiber end 14a) is also partially received.
For this reason, in this state, both the solid-state imaging devices 2a and 2b
In any case, uneven inspection light is received.

The inspection device TU performs an inspection by detecting the output when each solid-state image sensor 2 receives uniform light from the light irradiation device 10 while adjusting the illuminance. If the inspection light applied to the solid-state imaging device 2 becomes non-uniform, accurate inspection cannot be performed. For this reason, in the present inspection apparatus TU, irradiation of inspection light and inspection of the solid-state imaging device are performed in the following procedure, and an efficient and highly accurate inspection is performed.

FIG. 2 shows this inspection procedure. Here, the measurement is started from step S1. The following operation is started with light emitted from the light source 11 and with the shutters 16a and 16b closed by the shutter controllers 17a and 17b. First, an operation instruction signal is sent from the tester 30 to the prober. With this signal, the prober determines that the solid-state imaging devices 2a and 2b to be inspected are located immediately below both shutters 16a and 16b.
The wafer 1 is held, moved, and positioned by the transfer holding device (step S2). Next, as shown in FIG.
The probe pins 21 of the prober are brought into contact with the output terminals of these solid-state imaging devices 2a and 2b to make electrical connection with the tester 30 (step S3).

In this state, an operation instruction signal is sent from the tester 30 to the shutter controller 17a, and the shutter controller 17a controls the opening of the shutter 16a based on this signal. As a result, inspection light emitted from the light source 11 and subjected to various adjustments and having a constant and uniform illuminance is emitted with the shutter 16a opened and the shutter 16b closed. S
4). This state is shown in FIG. 3B, and the left solid-state imaging device 2a receives only the inspection light emitted from the optical fiber end 14a that has passed through the shutter 16a located immediately above the solid-state imaging device 2a. At this time, the shutter 16b is closed, and the inspection light emitted from the optical fiber end 14b is blocked here, so that the solid-state imaging devices 2a and 2b are not irradiated. Therefore, the left solid-state imaging device 2a is irradiated with inspection light having uniform illuminance.

The electric signal output from the solid-state imaging device 2a on the left side under the uniform irradiation of the inspection light is taken into the tester 30 via the probe pin 21 and inspected by the tester 30 (step S5). ). Thus, the inspection of the left solid-state imaging device 2a is completed. Then, an operation instruction signal is sent from the tester 30 to the shutter controller 17a.
a closes the shutter 16a.

Next, an operation instruction signal is sent from the tester 30 to the shutter controller 17b, and based on this signal, the shutter controller 17b controls to open the shutter 16b. As a result, this time, the inspection light emitted from the light source 11 and subjected to various adjustments and having a constant and uniform illuminance is emitted with the shutter 16b opened and the shutter 16a closed. (Step S
6). This state is shown in FIG. 3 (C), and the solid-state imaging device 2b on the right side receives only inspection light of uniform illuminance emitted from the optical fiber end 14b that has passed through the shutter 16b located immediately above it. . Therefore, the electric signal output from the solid-state imaging device 2b on the right side after receiving the uniform irradiation of the inspection light is transmitted to the tester 3 via the probe pin 21.
0 and is inspected by the tester 30 (step S7).

When the inspection of the two solid-state imaging devices 2a and 2b located below the light irradiation device 10 is completed in this way, an operation instruction signal is sent from the tester 30 to the shutter controller 17b, and the shutter control is performed by this signal. Table 17
b performs control to close the shutter 16b. Then, the prober removes the probe pins 21 from the solid-state imaging devices 2a and 2b (step S8). Thereafter, until the inspection of all the solid-state imaging devices 2 on the wafer 1 is completed, the process returns to step S2 and the inspection of the remaining solid-state imaging devices 2 formed on the wafer is performed in the same procedure as described above (step S2). To S8). When it is determined in step S9 that the inspection has been completed for all the solid-state imaging devices 2 formed on the surface of the wafer 1, this inspection is ended.

As described above, if the inspection apparatus TU shown in FIG. 1 is used, the two solid-state imaging devices 2
The inspection for a and 2b can be performed continuously while being held at this position. For this reason, the number of times of wafer transfer positioning and probe pin movement control is smaller than in the conventional case where wafer transfer positioning and probe pin contact movement control are performed each time one solid-state imaging device is inspected. Inspection time can be reduced by half. In particular, the switching control of the light irradiation by switching the operation of the shutters 16a and 16b can be performed in a short time. However, the transfer control of the wafer and the control of the movement of the probe pins are time-consuming. By
Inspection time can be significantly reduced.

In the above-described embodiment, the tip of the optical fiber is divided into two parts. However, if the tip is divided into three parts or more and a shutter is provided for each part and the same control is performed, the inspection time can be reduced. Can be further shortened. Further, the light from the light source is split by the optical fiber, but the splitting means is not limited to this. Also,
It is also possible to provide a plurality of light sources.

[0025]

As described above, according to the present invention,
A light irradiation device is configured to be able to irradiate a predetermined inspection light to a plurality of test objects at a time, and the light irradiation is switched for each test object by controlling the operation of a light blocking unit. Once the positioning of the test object with respect to the light irradiating means (positioning of the wafer) is performed once, the inspection of a plurality of test objects irradiated with light by the plurality of light irradiators is performed in the positioning state. Inspection time can be reduced, and inspection efficiency can be improved.

Further, according to the inspection apparatus of the present invention, in a state where it is possible to irradiate the inspection light from the light irradiating means to each of the plurality of test objects, the shielding control means controls the plurality of light shielding means. The operation is controlled to irradiate a predetermined light from only one of the light irradiating means to the corresponding test object, and the output signal from this test object is inspected by the inspection means. Inspection is possible.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of an inspection device provided with a light irradiation device according to the present invention.

FIG. 2 is a flowchart showing an inspection procedure by the inspection device.

FIG. 3 is a schematic front view showing a state in which a solid-state imaging device to be inspected is irradiated with inspection light in the inspection apparatus.

FIG. 4 is a flowchart showing an inspection procedure by a conventional inspection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wafer 2, 2a, 2a Solid-state imaging device 10 Light irradiation device 11 Light source 12 Illuminance adjustment device 13 Light uniformity device 14 Optical fiber 15a, 15b F value adjustment device 16a, 16b Shutter 17a, 17b Shutter controller 21 Probe pin 30 Tester

Claims (4)

[Claims] 1. A light irradiator having a plurality of light irradiators for irradiating a plurality of test objects with predetermined light, respectively, and a light blocker capable of selectively blocking light irradiation by the plurality of light irradiators. A light irradiating device comprising: a light blocking means; and a light blocking control means for controlling an operation of the light blocking means. 2. The light irradiation apparatus according to claim 1, wherein the plurality of objects to be inspected comprise a plurality of solid-state imaging devices formed in alignment on a wafer. 3. The light according to claim 1, wherein the light blocking means is provided in each of the plurality of light irradiators, and can block light irradiation by the corresponding light irradiators. Irradiation device. 4. The light irradiation device according to claim 1, further comprising: an output signal from each of the plurality of test objects when connected to each of the plurality of test objects and receiving light irradiation. Inspection means for inspecting the light, the interruption control means controls the operation of the light interruption means,
A control operation for inspecting an output signal from the object to be inspected by the inspection means in a state where the predetermined light is emitted to the corresponding object from only one of the light irradiators, An inspection device using a light irradiation device, wherein the inspection is performed sequentially on the irradiation device.