JPS63217636A - Wafer prober - Google Patents

Abstract

PURPOSE:To contrive complete automation of a card transferring system at the time of exchange of probe cards by a method wherein a desired probe card selected among a plurality of probe cards housed in a card housing rack is held by an extension arm, which, is arranged in a prober main body and is movable in both up-and-down and rotating directions, and this is transferred to an insert ring. CONSTITUTION:An expansion arm 23 is extended in such a way that a probe card placing plate 31 is inserted under the lower surface of a probe card 9 selected from among probe cards housed in a card housing rack 7 and thereafter, a vertically driving motor 36 is driven to make a base stand 21 ascend and the card 9 is placed on the plate 31. After being aligned, the card 9 is again placed and after a rotating motor 33 is driven to make a rotating base stand 22 rotate at 90 degrees, the arm 23 is extended to convey the card 9 up to the lower surface of an insert ring 6 provided on the lower surface of a test head 4 of a prober, the motor 36 is driven to make the stand 21 ascend and the card 9 is abutted on the ring 6. Thereby, a complete automation of work is contrived and the improvement of production efficiency, quality and yield can be contrived.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is a method for measuring electrical characteristics of semiconductor elements (hereinafter referred to as chips) formed in large numbers on the surface of a semiconductor wafer (hereinafter referred to as wafer). The present invention relates to a wafer prober equipped with an automatic probe card transfer device.

(Prior art) A wafer blower measures the electrical characteristics of each chip formed on a wafer and eliminates chips determined to be defective before the assembly process, reducing costs and improving productivity. This is a device to contribute to the

By the way, in recent years semiconductor manufacturing processes have been required to improve productivity, yield, and quality.
As wafers become larger in diameter and automation of manufacturing equipment progresses, the same applies to probers. A bar has been developed.

However, in recent years, due to the high integration and diversification of chips, the number of low-volume, high-mix production processes has increased, and as a result, the number of operations required by operators has increased significantly.

In particular, the probe card needs to be replaced for each type of chip to be specified. For example, when measuring a chip of X type and then a chip of Y type, change the probe card according to the Y type. It is necessary to replace it.

Conventionally, such probe card replacement methods required the operator to loosen screws on the head plate, remove the probe card, and then install a probe card suitable for type Y. was done by artificial means.

(Problems to be Solved by the Invention) However, as mentioned above, in the conventional wafer prober, the operator manually replaces the probe card every time the type of wafer is replaced, which is contrary to automation in the semiconductor manufacturing process. Needless to say, it is extremely difficult to improve productivity, yield, quality, etc.

In particular, the probe card's stylus lacks durability due to drag on the tip, so in order to obtain highly reliable measurement results, the probe card must be replaced repeatedly. Not only does it take a lot of time to replace the probe and select the type, it becomes an obstacle to shortening the work time.In addition, when installing the probe card, the operator may drop the probe card during transportation and damage it. There was also a fear that it would happen.

Therefore, the present invention has been made to solve the above-mentioned problems, and it automates the probe card transport system to facilitate full prober automation, improve productivity and yield, and improve probe card exchange. An object of the present invention is to provide a wafer blobber that can improve safety.

[Structure of the Invention] (Means for Solving the Problems) The wafer prober of the present invention measures a wafer by contacting a stylus attached to a probe card with the electrode pads of a large number of semiconductor elements formed on a semiconductor wafer. In the prober,
The probe cards can be automatically exchanged via a transport am equipped with a telescoping arm that arranges a plurality of types of probe cards at predetermined positions and takes out the probe cards according to a preset program and transports them to the insert ring. It is characterized by being configured as follows.

(Function) The extendable arm, which is placed inside the blower body and can move vertically and rotationally, grasps a desired probe card from among the multiple probe cards stored in the card storage shelf and transports it to the insert ring. This makes it possible to fully automate the card transport system when exchanging probe cards, making it easier to fully automate the blower, improving productivity, yield, and safety when exchanging probe cards.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing the appearance of the wafer blobber of the example.
Reference numeral 1 is the main stage of the wafer prober, and reference numeral 2 is the loader stage of the wafer prober.

Wafer cassettes 3a and 3b that accommodate wafers are arranged in the loader stage 2. For example, when measuring wafers in the wafer cassette 3a, the wafer cassette 3a is
A wafer transport mechanism (not shown) takes out the wafer and transports it to the measurement position, and the wafer after measurement is transported to and stored in the wafer cassette 3b in the reverse order.

Reference numeral 4 designates a test head, which is rotatably attached to the prober body via a rotary shaft 5.

A ring-shaped insert ring 6 is provided at the center of the upper surface of the main stage 1, and a probe card is attached to this insert ring 6. During wafer measurement,
The test head 4 is in close contact with the main stage 1, and at this time, the detection signal detected by the stylus of the probe card is transmitted to the probe card, insert ring 6,
The signal is transmitted to a blower tester (not shown) via a measurement circuit within the test head 4.

On the other hand, on the left side of the main stage 1, there is a card storage rack 7 that accommodates a plurality of probe cards, and a desired probe card is automatically taken out from this card storage rack 7 to the probe card mounting position, that is, the bottom surface of the insert ring 6. Probe card automatic transport 11118 that transports this
is provided.

FIG. 2 is a diagram showing a more detailed structure of the probe card automatic transport mechanism 8 and the lower surface part of the test head 4.
is accommodated.

Reference numeral 21 is the base of the probe card automatic transport mechanism;
A rotary base 22 is arranged on this base 21 with a gap maintained therebetween.

Arranged on the rotating base 21 is a telescopic arm 23 that is freely telescopic and has a structure in which a number of links are connected in an X shape with pivot pins.

A telescoping arm drive screw 24 is parallel to the direction of extension and contraction of this telescoping arm 23.
is attached to the rotating base 21 at both ends by sliding support members 25a and 25b. A pole nut 26 is screwed onto the telescoping arm drive screw 24.
6 and a support pin 27 of the telescopic arm 23 are connected by a nut connecting plate 28.

Further, a telescopic arm drive motor 29 is installed on the rotating base 22, and a gear 29a provided on the rotating shaft of this 29.
and a gear 24a provided at one end of the telescopic arm drive screw 24 are connected by a timing belt 30.

That is, the telescoping action of the telescoping arm 23 is achieved by transmitting the rotation of the telescoping arm drive motor 29 mounted on the rotation base 22 to the drive screw 24 via the timing belt 25, and by this rotation, the telescoping arm 23 is screwed into the drive screw 24. By moving the pole nut 27, the pole nut 27 and the support pin 2 of the telescopic arm 23 are
This is done by moving the nut connecting plate 29 that connects the parts 8 and 8.

A disk-shaped probe card mounting plate 31 is attached to the tip of the extendable arm 23, and probe card support pins 32 are protruded from the periphery thereof at 120 degree intervals.

On the other hand, a rotary motor 33 is attached to the base 21, and a gear is attached to the rotating shaft of the rotary motor 33. It is connected to the rotating base rotating shaft (not shown) by a timing belt. That is, by rotating the rotary motor 33, the rotary base 22 is rotated.

By the way, the base 21 can be moved up and down in the Z-axis direction by a vertical drive mechanism. It is composed of a drive motor 36.

A gear is attached to the rotating shaft of the vertical drive motor 36, and this gear is connected to a gear inserted through the lower end of the vertical drive screw 35 via a timing belt.

The three vertical guide shafts 34 extend vertically from the prober main body by passing through bearing members 38 provided on the base 21, and the penetrating portions have a slidable structure. Further, a pole nut 37 is screwed onto the vertical drive screw 35.
This pole nut 37 is fixed to the base 21.

That is, the vertical movement structure of the base 21 is controlled by the rotation of the vertical drive motor 36. By rotating the L drive screw 35,
This is done by raising and lowering the pole nut 37, which is integrated with the base 21 screwed onto the vertical drive screw 35.

The operation of such a probe card automatic transport device will be explained.

First, the probe card 9 corresponding to the wafer type is selected based on the wafer type information programmed in advance in the storage mechanism of the prober CPU, and the probe card mounting plate 31
After extending the telescoping arm 23 so that the selected probe card 9 is inserted into the lower surface of the selected probe card 9 stored in the card storage rack 7, the vertical drive motor 36 is driven to raise the base 21 and move the probe card mounting plate The probe card 9 is placed on the probe 31. Then, the probe card 9 is temporarily placed on a probe card alignment mechanism (not shown) and aligned.

After the alignment is completed, the probe card 9 is placed again, the rotary motor 33 is driven to rotate the rotary base 22 by 90 degrees, and the telescopic arm 23 is extended to insert the insert provided on the lower surface of the test head 4 of the prober. The probe card 9 is conveyed to the bottom surface of the ring 6, and then the vertical motor 36 is driven to move the probe card 9 to the base 2.
1 and then probe card 9 and insert ring 6.
and come into contact with. Thereafter, the probe card 9 and insert ring 6 are fixed by the probe card fixing mechanism.

By the way, the probe card fixing mechanism may be any type of mechanism. For example, in this example, positioning pins 42 each driven by a plurality of air cylinders 41 are mounted on the test head 4 side at multiple locations on the outer periphery of the insert ring 6. The positioning pin 42 presses and fixes the card holder portion 9a of the probe card 9 from below.

That is, radial fixing grooves 9b are provided at a plurality of locations on the lower surface of the card holder 9a, and the positioning pins 42 are fitted into the fixing grooves 9b.

As described above, according to the prober of the present invention, it is possible to completely automatically transport the probe card to the insert ring of the test head, so there is no chance of the operator dropping the probe card and damaging it while transporting it. Furthermore, if you want to fully automate the work, for example by automating the attachment and detachment of the probe card and insert ring, this can be easily accommodated, and production efficiency, quality, and yield can be improved. .

Additionally, a scalar robot or the like may be used as the transport mechanism.
In this case, multiple types of 10-book cards may be placed on a ring-shaped card placement plate instead of the probe card storage shelf.

[Effects of the Invention] As explained above, the wafer prober of the present invention greatly contributes to complete automation of work and improves production efficiency, quality, and
Yields can be improved, and it becomes easier to respond to small-volume production of other products.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the appearance of a wafer 10-bar according to an embodiment of the present invention, and FIG. 2 is a diagram showing the structure of an automatic probe card transport mechanism. 4... Test head, 6... Insert ring, 7... Card storage rack, 8...
... Probe card automatic transport mechanism, 9 ... Probe card, 21 ... Base, 22 ...
・Rotating base, 23... Telescopic arm, 24...
- Telescopic arm wA moving screw, 29... Telescopic arm drive motor, 31... Probe card mounting plate, 33...
... Rotating motor, 35 ... Vertical drive screw,
36... Vertical drive motor. Applicant Tokyo Electron Co., Ltd. Agent Patent Attorney Sasa Suyama - Closed 1

Claims (2)

[Claims] (1) In a wafer prober that measures by contacting a stylus attached to a probe card to the electrode pads of a large number of semiconductor elements formed on a semiconductor wafer, a plurality of probe cards are arranged at predetermined positions, and A wafer prober characterized in that the probe card is configured to be automatically exchangeable via a transfer mechanism equipped with an extendable arm that takes out the probe card and transfers it to an insert ring according to a preset program. (2) The wafer prober according to claim 1, wherein the extendable arm has a structure in which a large number of links intersect in an X shape, and the intersections and joints are connected by pivot pins. .