JPH0758312B2 - Wafer prober - Google Patents

Description

The present invention relates to a wafer prober for measuring the electrical characteristics of a chip formed by contacting a chip formed on a semiconductor wafer such as silicon with a probe needle. Regarding

[Prior Art] In a wafer prober, a probe needle is sequentially brought into contact with each electrode of a large number of chips formed on a semiconductor wafer, and the electrical characteristics of each chip are measured. Since a large current flows, the needle tip is oxidized, or aluminum scraps or the like are attached to the probe needle because the probe needle and the electrode are pressed against each other. When such probe needles are oxidized or Al is attached, correct measurement cannot be performed and the yield of products (chips) is reduced. Therefore, the wafer prober 2 is generally mounted on the wafer mounting table 7 (chuck) as shown in FIG. A ceramic plate 10 for polishing the probe needle is placed on the side of or on the wafer mounting table 7, and the ceramic plate is brought into contact with the probe needle 51 from below to scrape and polish the needle tip.

[Problems to be Solved by the Invention] However, since such conventional polishing of a probe needle sharpens the needle tip, the life of the probe needle naturally becomes short,
I had to change the probe card frequently.
Further, as shown in FIG. 6, when Al debris or the like is attached to other than the needle tip, there is a drawback that it cannot be completely removed.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art and provides a wafer prober that can keep probe needles clean at all times without wearing them and thus maintain highly accurate measurement.

[Means for Solving the Problems] In order to achieve such an object, the wafer prober of the present invention is a wafer prober including a probing portion provided with a probe card attachment portion, and a probe needle arranged on the probe card. Cleaning means for cleaning the probe card, and a conveying means for conveying the probe card removed from the probe card mounting portion to the cleaning means, and a probing portion provided with the probe card mounting portion and a probe card. In a wafer prober having a probe card supply section for supplying a probe card with an automatic probe card exchange function, a cleaning means for cleaning probe needles arranged on the probe card and a plurality of probe cards are stored in the probe card supply section. The stocker and the probe card stored in the stocker A cleaning means for transferring the probe card removed from the probe card mounting portion to the cleaning means, and in particular, an ultrasonic cleaner or a cleaning means as the cleaning means. It is characterized in that it is provided with an agent injection nozzle. By cleaning the oxides or deposits generated on the probe needles by such a cleaning means, the oxides or deposits are removed without wearing the probe needles.

Next, a case where an ultrasonic cleaner is provided as a cleaning means and a case where a cleaning agent injection nozzle is provided will be described with reference to examples.

[Embodiment 1] The wafer prober 1 shown in FIG. 1 is a wafer prober with a probe card automatic exchange function including a wafer transfer section 2, a probing section 3 and a probe card supply section 4, and the probe card supply section 4 has a plurality of probes. It comprises a stocker 41 for accommodating the card 5 and a handling arm 42 for taking out the probe card 5 from the stocker 41 and transporting it to the probe card mounting portion 31 of the probing unit 3.

An ultrasonic cleaner 6 is installed as a probe needle cleaning means in the vicinity of the probe card supply unit 4. In FIG. 1, the probe card supply unit 4 is installed on the front side of the prober 1 and the ultrasonic cleaning device 6 is installed on the rear side of the prober 1. However, they may be replaced with each other. It is desirable that the probe card 5 be located at a position where it can be conveyed to the ultrasonic cleaner 6 by the arm 42.

As shown in FIG. 2, the ultrasonic cleaner 6 is a known device including a container 61 for storing a solvent such as alcohol and a dish 62 for generating ultrasonic waves by a driving device (not shown) and on which the probe card 5 is placed. Then, the probe needle 51 of the probe card 5 placed on the dish 62 is washed by the cooperation of the ultrasonic vibration and the solvent.

For example, as shown in FIG. 3, the arm 42 has means for mechanically locking the probe card 5 by opening and closing the tip, and it is extendable / contractible with respect to the rotating shaft 43. It is conveyed between the unit 31, the stocker 41, and the ultrasonic cleaner 6.

In the above configuration, for example, after the probe card 5 after probing is released from the attachment portion 31,
It is conveyed to the ultrasonic cleaner 6 by the handling arm 42, where the probe needle is cleaned and stored again in the stocker 41 by the handling arm 42. This allows the probe needle to be kept clean at all times.

Second Embodiment In the embodiment shown in FIG. 4, the cleaning means 8 may be installed, for example, in the vicinity of the chuck 7 on which the wafer is mounted.
The cleaning means 8 is composed of a spray nozzle 81 for spraying a cleaning solvent such as alcohol onto the probe needle and a tray 82 for collecting the solvent after cleaning.

The injection nozzle 81 is connected to a solvent tank and an air supply source (not shown), and can inject a solvent at a constant amount and a constant pressure onto the probe needle by an operator's operation or the like.

In this case, by providing the cleaning means 8 in the conventional needle polishing mechanism, the probe card can be locked by the probe card locking means in the conventional needle polishing mechanism for cleaning.

"Effects of the Invention" As is clear from the above embodiments, the wafer prober of the present invention is a wafer prober having a probing portion provided with a probe card attachment portion, and is for cleaning probe needles arranged on the probe card. Since the cleaning means and the conveying means for conveying the probe card removed from the probe card mounting portion to the cleaning means are provided, the probe needle can be kept clean without polishing as in the conventional case, and high measurement accuracy can be maintained. . Moreover, since the probe needle does not wear, the frequency of replacement of the probe card can be reduced, and the burden on the operator can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a wafer prober according to the present invention, FIGS. 2 and 3 are diagrams showing the essential parts of the same embodiment, and FIG. 4 is an embodiment different from FIG. FIG. 5 is a diagram showing a conventional probe needle polishing mechanism, and FIG. 6 is a diagram showing contamination of the probe needle. 1 ... Wafer prober 4 ... Probe card supply unit 5 ... Probe card 51 ... Probe needle 6 ... Ultrasonic cleaner (cleaning means) 8 ... Cleaning means 81 ... Injection nozzle

Claims (4)

[Claims] 1. A wafer prober having a probing portion provided with a probe card mounting portion, a cleaning means for cleaning probe needles arranged on the probe card, and the probe card detached from the probe card mounting portion. And a transfer means for transferring the cleaning means to the cleaning means. 2. A wafer prober provided with a probe card mounting portion and a probe card supply portion for supplying a probe card, and having a probe card automatic exchange function. A cleaning means for cleaning the needle, a stocker for storing the plurality of probe cards in the probe card supply section, and a transport means for transporting the probe card stored in the stocker to the probe card mounting section, The wafer prober, wherein the carrying means has a function of carrying the probe card removed from the probe card mounting portion to the cleaning means. 3. The wafer prober according to claim 1, wherein the cleaning means is an ultrasonic cleaning device. 4. The wafer prober according to claim 1, wherein the cleaning means is a cleaning liquid jet nozzle.