JPH079920B2 - Clean prober device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a clean prober device.

(Prior Art) Prober devices are well known to those skilled in the art. For example, a semiconductor wafer prober conveys a wafer from a wafer cassette to a measurement stage, electrically connects semiconductor chips regularly formed on the wafer mounted on the measurement stage to a probe card, and measures electrical characteristics. Ink was attached to the defective chip by a marker such as an inker.

(Problems to be Solved by the Invention) Miniaturization of integrated circuits has been remarkably developed along with technological innovation, and an environment corresponding to this miniaturization technique is required. In order to create an environment compatible with such miniaturization technology, it is necessary to eliminate dust contained in the air as much as possible. That is, even in the measuring device, it is necessary to suppress the generation of dust as much as possible and to eliminate the dust. For example, the miniaturization of integrated circuits is progressing further, and in 4M DRAM, most users require cleaner prober devices. Some users have already banned the use of belts and the operation of the prober device in the clean bench even during 1MDRAM manufacturing. On the other hand, the conventional prober has an X- and Y-axis lead screw mounted on an iron plate with a thickness of 10 to 150 cm. For this reason, some kind of oil or grease is naturally used, so if clean air or the like is blown into the structure with a small number of outlets, the air inside the equipment may be diffused, resulting in an extremely low degree of cleanliness. . However, in the conventional prober device, although various measures have been taken to prevent dust generation,
Still, since a ball screw and a motor belt are used to move the measurement stage up and down, dust is generated even though it is slight. In reality, no means is provided for removing this dust.

The present invention has been made to improve the above points,
Provided is a clean prober device which can reduce the adhesion of dust to an object to be measured and improve the yield.

[Configuration of Invention] (Means for Solving Problems) A clean prober device according to the present invention stores a prober unit for measuring electrical characteristics of an object to be measured placed on a mounting table and the object to be measured. In the prober device including a loader unit having a mounting table for the cassette, the prober unit includes a means for supplying clean air to at least a region surrounding the object to be measured mounted on the mounting table, and the prober unit. Discharger for forcibly discharging the air of the prober to the outside of the housing of the prober section, and the loader section is parallel to the measured object stored in the cassette mounted on the cassette mounting table. And a discharge means for forcibly discharging the clean air to the outside of the housing of the load section.

(Operation) In a probe device for measuring the electrical characteristics of an object to be measured placed on a mounting table, the object to be measured in the probe device, that is, the object to be measured mounted on the mounting table and the cassette mounting of the loader section. By providing means for supplying clean air to each of the objects to be measured housed in the cassette placed on the table, and forcing each of these air to be forcibly discharged to the outside, This has the effect of reducing dust adhesion and improving yield.

(Example) Next, an example in which the clean prober device of the present invention is applied to a semiconductor wafer prober for measuring a semiconductor wafer as an object to be measured will be described with reference to the drawings.

This semiconductor wafer prober is mainly composed of a loader section 3 for accommodating the wafer 1 and transferring the wafer 1 to a measuring section, and a prober section 5 for measuring the transferred wafer 1.

The structure of the loader unit 3 is such that four systems of cassette mounting bases 11 on which the wafer cassettes 10 containing the wafers 1 are mounted are arranged, and the cassette mounting bases 11 are connected to the rotating shafts 13 engaged with the motors 12, respectively. The cassette mounting table 11 can be moved up and down by a predetermined amount by the rotation of the motor 12. For example, 25 wafers 1 are stored in one wafer cassette 10 at appropriate intervals. This wafer cassette
The 10 has a structure that allows air to flow between the rear side and the front side. Behind the wafer cassette 10, the four systems, the ventilation plate 15 such as 700 mm in length and 100 mm in width,
A thickness of 3 mm is provided, and on one side of the ventilation plate 15 on the side of the wafer cassette housing portion, ventilation holes 16 are set at predetermined intervals as shown in FIG. From this ventilation hole 16, a tube 18 connected to the clean air suction part 7
Is connected to the nozzle 19 of the ventilation plate 15 so that clean air is ejected. This clean air suction part 7
Is provided behind the ventilation plate 15, and a nozzle 22 for sucking air from the outside of the wafer prober housing is provided so as to project to the outside of the housing. The air sucked from the nozzle 22 is removed by a filter 23 corresponding to, for example, 0.01 micron dust. The dust-removed clean air is sent to the tubes 18 and 36 at a controlled rate of 30 per minute.

A power supply unit 4 is arranged on the bottom surface of the front surface of the loader unit 3, and a floor-direction surface excluding the power supply unit 4 is provided with ventilation holes to allow ventilation, for example, as shown in FIG. It is 8a. This grating structure 8a
A fan 9a is provided on the floor-side surface of the as a ventilation fan for promoting the discharge of air. Also this loader unit 3
The vacuum suction tweezers 20 for loading and unloading the wafer 1 from the wafer cassette 11 and the vacuum suction tweezers 20.
A pre-alignment stage 21 is provided for placing and pre-positioning the wafer 1 transferred from the.

Next, the prober unit 5 will be described.
A measurement stage 30 capable of driving in the directions Y, Y, Z, and θ is installed, and a plurality of ventilation holes, for example, a grating structure is formed in the drive guide plate 30b in the X and Y directions. There is. The wafer 1 is transferred from the pre-alignment stage 21 of the loader unit 3 to the measurement stage 30 by a vacuum suction arm (not shown). Measuring stage 30
The head plate 31 of the prober unit 5 housing facing the
The probe card 32 is installed, and the probe needle 33 is attached to the probe card 32. The head plate 31 has, for example, a hollow structure with a thickness of 30 mm, and nozzles 35a project toward the measurement stage 30 at four locations around the probe card 32 at 90 ° intervals. A nozzle 35b also projects downward from the square of the head plate 31. These nozzles 35a and 35b are
It is connected to an air tube 36 provided in the head plate 31, and this air tube 36 is connected to the clean air suction section 7. An operation panel 37 is installed on the front side of the prober unit 5.
A CPU 38 for controlling each operation of the semiconductor wafer prober is installed below. The floor direction surface excluding the CPU38 device has a grating structure 8b similar to that of the loader unit 3, and the fan 9b also functions as a ventilation fan.
Installed as well.

Next, the flow of clean air (down blow) will be described.

First, the flow of the loader will be described with reference to FIG. Air outside the housing is sucked through a nozzle 22 provided in the clean air suction portion 7, dust contained in the air is removed by a filter 23 and converted into clean air. This clean air is sent to the loader section and the prober section through the tubes 18 and 36.

Regarding the loader section 3, the clean air is transmitted from the clean air suction section 7 through the tube 18 to the nozzle 19 of the ventilation plate 15.
Then, the air enters the ventilation plate 15, and clean air is ejected from the ventilation hole 16 of the ventilation plate 15. The jetted clean air passes through the inside of the wafer cassette 10 as shown by the arrow 50, and the clean air is guided toward the floor as shown by the arrow 51 by the action of the fan 9a.
It passes through the bottom surface of the grating structure 8a and is discharged to the outside of the housing.

Next, the prober unit 5 will be described. As shown in FIG. 3, the clean air is sucked from the clean air suction portion 7, travels through the tube 36, and is jetted from the nozzles 35a and 35b which are set to be scattered on the head plate 31. The positions of the nozzles 35a and 35b are formed so as to set the cleanliness by spraying on the semiconductor wafer which is the object to be measured. The clean air ejected from the nozzle 35a set around the probe card is blown to the measurement stage as shown by the arrow 52, and the action of the fan 9b causes the grating structure provided on the guide plate 30b of the measurement stage 30 as shown by the arrow 54. After passing through the ventilation hole, it is guided toward the floor as shown by arrow 53, passes through the bottom surface of the grating structure 8b, and is discharged to the outside of the housing. In addition, the clean air ejected from the nozzle 35b set on the square of the head plate 31 is the arrow 55 as it is.
And goes through the bottom surface of the grating structure 8b.
Next, the measurement of the wafer will be described. First, a wafer cassette 10 containing, for example, 25 wafers 1 is placed on a cassette placing table 11. This wafer cassette 10 always has a ventilation plate.
Clean air is blown from 15 to prevent dust and dirt from adhering to the wafer 1. The vacuum suction tweezers 20 for the wafer 1 are inserted from the wafer cassette 10 in parallel into the respective gaps of the wafer cassette 10, the wafer 1 is vacuum-sucked at one end of the tweezers 20, and the wafer 1 is taken out according to a predetermined program.
Transport to 21. The wafer 1 transferred to the pre-alignment stage 21 is pre-positioned with reference to the orientation flat or the like. The pre-positioned wafer 1 is transferred to the measurement stage 30 by the vacuum suction arm. Here, the measuring stage 30
The measuring stage 30 is driven in the X and Y directions by known means.
The wafer 1 placed on is accurately positioned. After this,
The measurement stage 30 is set at a predetermined position, and the measurement stage 30 is raised from below to probe the probe needle 33 attached to the probe card 32 to the electrode portion of the semiconductor chip formed on the wafer 1.
And the electrical characteristics are measured. During the measurement, clean air is constantly ejected from the nozzles 35a and 35b installed on the head plate 31, so that dust or dirt does not adhere to the wafer 1. Further, dust or dirt generated for any reason is discharged to the outside of the wafer prober casing along the clean air flow path. The wafer 1 after the measurement is returned to the original position of the wafer cassette 10 by the vacuum suction tweezers 20 and the vacuum suction arm. In order to take out the second wafer from the wafer cassette 10, the horizontal position of the vacuum suction tweezers 20 is fixed, and the cassette mounting table 11 is raised by a predetermined set interval so that the next wafer 1 can be taken out. All of the wafers 1 stored in the wafer cassette 10 are configured to be executed in an automatic continuous process according to a predetermined program.

In the above embodiment, the clean air is discharged to the outside of the wafer prober casing in the floor direction, which is the grating structure 8a, 8b. However, a wafer prober is usually used in an environment of clean room class 100 or less (100 particles of 1 μm in 1 m ³ or less). Depending on the structure of the clean room, the wind speed of the discharged clean air will cause It can be said that there is a possibility that dust will be scattered around. Therefore, it is not necessary to adopt a structure in which the air is directly discharged to the outside of the housing as in the above embodiment. For example, in the above-described embodiment, the suction mechanism 40 for sucking the clean air that may contain dust that has passed through the grating structures 8a and 8b is installed. This inhalation mechanism 40
As shown in FIG. 6, is provided on the lower side of the grating structures 8a and 8b, and sucks air by a known vacuum action. The air sucked in here passes through the hose 41 extending from here to the outside of the clean room, and is discharged to the outside of the wafer prober and the clean room.

As yet another embodiment, an intake mechanism may be provided below the grating structures 8a and 8b, and the air sucked in here may be blown again to the clean air intake section 7 installed in the loader section 3 by the hose 42. A filter 43 is provided to remove dust contained in the air taken in at this time.

The present invention is not limited to the above-mentioned embodiment, and it is desirable that the device structure is adapted to the cleanness required by the object to be measured.

For example, it is possible to adjust the number of nozzles and setting positions for ejecting air in the above-described embodiment, and the number of ventilation plates, the installation positions and the number of ventilation holes. Further, the structure of the bottom surface of the housing may be devised, and the number of fans can be increased or decreased.

In the above embodiment, an example in which the down blow air was cleaned and blown again in the probe device was described, but this air may be discharged to the outside of the clean room without being recirculated. Further, since the probe device is installed in the clean room, the down blow may be formed by forming a negative pressure at the bottom of the probe device to form the air suction feed path.

[Advantages of the Invention] As described above, according to the present invention, in the probe device for measuring the electrical characteristics of the measured object placed on the mounting table, the measured object in the probe device, that is, the mounting table is A means for supplying clean air to the measured object placed and the measured object stored in the cassette placed on the cassette mounting table of the loader unit is provided, and the clean air is forcibly externally supplied. The provision of the means for discharging the particles has the effect of reducing the adhesion of dust to the object to be measured and improving the yield.

[Brief description of drawings]

FIG. 1 is a state explanatory view for explaining an embodiment of the clean prober device of the present invention, FIG. 2 is a view showing an air flow path of FIG. 1 by an arrow, and FIG. 3 is an air flow of FIG. Nozzle installation explanatory drawing, FIG. 4 is a drawing of the grating structure of FIG. 1, FIG. 5 is a drawing of the ventilation plate of FIG. 1, and FIGS. 6 and 7 are other embodiments of FIG. FIG. 1 …… Wafer 7 …… Clean air suction part 8a, 8b …… Grating structure 9a, 9b …… Fan 15 …… Ventilation plate 18,36 …… Tube 35a, 35b …… Nozzle

Claims (1)

[Claims] 1. A probe apparatus comprising: a prober section for measuring electrical characteristics of an object to be measured mounted on a mounting table; and a loader section having a mounting table for a cassette for accommodating the object to be measured. The prober unit includes means for supplying clean air to at least a region surrounding the object to be measured placed on the mounting table, and an exhaust unit for forcibly exhausting the air of the prober unit to the outside of the housing of the prober unit. And a loader section for supplying the clean air in parallel to the object to be measured housed in the cassette mounted on the cassette mounting table, and the load of the clean air. And a discharge means for forcibly discharging it to the outside of the case.