JPH05259247A - Prober for solid image-pickup element - Google Patents

Abstract

PURPOSE:To reduce a black defect on a solid image-pickup element by carrying a wafer with a device surface facing downward by an arm and making a surface of a wafer stage itself for mounting the wafer face downward. CONSTITUTION:A wafer stage 3 is designed to suck a wafer so that it faces downward, wherein when the wafer is carried by an arm with its device surface downward, the wafer is sucked by the wafer stage 3 as it is. In addition an air shower 13 for blowing off dust attached to a probe is also incorporated. Since a signal of an image sensor 9 is output to a monitor 12 and a device pad is aligned with the probe based on the image, operation is easy to do. Thus there is no difficulty in operativity by an apparatus constitution being reverse vertically to a conventional one, instead total development together with a machine such as a light source may reduce an opportunity that a man is concerned with fine adjustment during operation or routine work, resulting in a reduction in black defects of the solid image-pickup element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a prober for measuring a solid state image pickup device in a wafer state.

[0002]

2. Description of the Related Art A conventional prober, as shown in FIG.
A loader unit 10 for setting a wafer, a wafer stage 3 on which the wafer 1 is placed, an arm 2 for carrying the wafer 1 to the wafer stage 3, an alignment unit 11 below the wafer stage 3, an image sensor 5 for counting the number of wafers. , An image sensor for alignment 6, a light source 7, a probe card 4, a microscope 9 used for alignment, and is connected to a solid-state image sensor tester 8 by a cable.

Next, the operation will be described. First, the wafer 1 to be measured is set on the loader unit 10. After that, when the program in which the device parameters are input in advance is executed, the image sensor 5 of the loader unit 10 counts the number of wafers. When the counting is completed, the arm 2 starts picking from the first wafer, and the first wafer is placed on the wafer stage 3. At this time, the arm 2 and the wafer stage 3 are
A small hole is formed on the surface in contact with the wafer, and the wafer is fixed by evacuating the inside of the hole.

When the wafer is placed on the wafer stage 3, the alignment is started according to the device parameters inputted in advance. The alignment is performed by moving the wafer stage 3 under the image sensor 6 and reading the device configuration and comparing it to the data. At the end of the prober alignment, humans make fine adjustments. At this time, the microscope 9 is placed directly above the probe guard 4.
Bring in and visually align the probe with the pad of the device.

After that, the prober can automatically load and align the wafers for several wafers and automatically measure all the set wafers.

By the above operation, the solid-state image pickup device on the wafer is measured. However, dust that falls on the device surface and fine particles that are contained in human breath during final adjustment by human eyes, pad scrapes scraped by probe needle pressure when the wafer moves, dust flow due to other moving parts, There is a big problem such as fire up, which causes a black defect of the solid-state image sensor.

[0007]

As described in the conventional example, in the prober of FIG. 2, since the measurement wafer is facing upward, dust and human drops falling on the device surface during the final fine adjustment by human eyes. The fine particles contained in the breath of the eye, the scraps of the pad scraped by the stylus of the probe when the wafer moves, and the like adhere to the effective pixels of the solid-state image sensor and cause black scratches.

Further, since the wafer of the solid-state image pickup device faces upward, there is a drawback that the solid-state image pickup device is damaged only by dropping a component or the like.

[0009]

According to the prober for a solid-state image pickup device of the present invention, an arm moves a wafer downward,
The wafer is attracted to the underside of the wafer stage with the device side facing down, the light source and other peripheral devices are located at the bottom of the prober, and air is blown around the probe card to blow off dust adhering to the probe. Equipped with shower device.

[0010]

FIG. 1 shows an embodiment of the present invention. Similar to FIG. 2, there are a wafer 1, an arm 2, a wafer stage 3, a probe card 4, an image sensor 5, an image sensor 6, a light source 7, a loader unit 10, and an alignment unit 11, and in addition to this, an image sensor 9, Monitor 12, air shower 13,
It is equipped with a mirror 14 and is connected to the solid-state image sensor tester 8 via a cable.

The wafer stage 3 attracts the wafer downward. When the wafer is carried by the arm 2 with the device surface facing downward, the wafer
It is adapted to be adsorbed on the stage 3. The conventional device for driving devices such as the probe card 4, the light source 7, the solid-state image sensor 8 and the like are all arranged upside down. Also, probe card 4
Air blower to remove dust adhering to the probe at a position that does not interfere with measuring the device near the
Shower 13 is also incorporated.

In the present invention, since the alignment by the prober is performed by the image sensor 6 as in the conventional case, there is no inconvenience that the prober is positioned upside down.

For fine adjustment by human eyes, the microscope is stopped, the signal of the image sensor 9 is output to the monitor 12, and the device pad and the probe are aligned based on the image, so that the work becomes easy. There is.

Since the drive circuit associated with the conventional probe card 4 and the solid-state image sensor tester is composed of a drawer-like unit, there is no problem in operation.

Since the light source 7 uses the mirror 14 to irradiate the device surface with light by reflection, there is no need to direct the light upward, and it is possible to supply parallel light as in the conventional case.

Further, in the present invention, when the light source is integrally formed with the light source, the operability is further increased and the appearance is neat. Furthermore, since the signal cables such as GP-IB can be put together when they are connected to the solid-state image sensor tester 8 or the like, the probability of trouble occurrence due to poor signal transmission between devices, which has occurred in the past, is reduced.

As described above, there is no difficulty in operability due to the device configuration being upside down from the conventional one, and rather, human beings intervene in fine adjustment during operation and daily routine by total development with equipment such as light source. Since the chances of doing so are reduced, the reliability of the device itself is increased.

Further, since the wafer stage 3 is arranged so that the wafer faces the device surface and the air shower 13 for blowing off the dust adhering to the probe is provided, the black defect of the solid-state image pickup device is caused. Decreases.

Further, not only in the solid-state image pickup device but also in the semiconductor integrated circuits in general, when the characteristic of the tester is checked, the structure of the prober is made to be the structure of the present invention, so that the structure of the device including the tester is neat and the device performance is improved. Needless to say

[0020]

As described above, according to the present invention, the wafer is carried by the arm with the device surface facing downward, and the surface of the wafer stage itself on which the wafer is mounted faces downward, so that the wafer falls from above. No dust is attached to the solid-state image sensor. In addition, since the surface of the wafer stage on which the wafer is placed faces downward, the entire device configuration will be reversed upside down from the conventional one, and the configuration will be more rigorous, reducing the chance of human intervention in daily operations. The reliability of the device also increases.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a prober for a solid-state image sensor according to the present invention.

FIG. 2 is a configuration diagram of a conventional prober.

[Explanation of symbols]

 1 Wafer 2 Arm 3 Wafer Stage 4 Probe Card 5 Image Sensor 6 Image Sensor 7 Light Source 8 Solid-State Image Sensor Tester 9 Image Sensor 10 Loader Section 11 Alignment Section 12 Monitor 13 Air Shower 14 Mirror

Claims (1)

[Claims] 1. A loader unit for setting a wafer, a wafer stage for holding and fixing the wafer, an arm for transferring the wafer to the wafer stage, an alignment unit for positioning the wafer stage, and an image sensor for counting the number of wafers. In the prober for a solid-state image sensor, which includes at least an image sensor for alignment, a light source for illuminating a wafer, a probe card for evaluating characteristics of the solid-state image sensor on the wafer, and a solid-state image sensor tester, wafer alignment is performed. An image sensor and a monitor for confirmation are provided, the wafer stage has a wafer holding surface facing downward, a mechanism for holding and fixing the wafer main surface facing downward, and the arm has a structure for transporting the wafer while facing downward. The light source and the probe card are arranged below the wafer stage, and the probe card is A prober for a solid-state imaging device, comprising an air shower device for blowing off dust adhering to a probe of a probe card.