JPH0472645A - Wafer prober - Google Patents

Abstract

PURPOSE:To make a test in an always uniform contact state by a method wherein a raised pressure is stored as a good-product pressure data, the contact on all chips is confirmed by means of a monitor needle by using the data and, after that, a pressure according to the good-product pressure data is exerted. CONSTITUTION:A pressure is input/output from and to the lower part; a stage 4 is raised and lowered; at this time, a pressure 5 is raised form a point where the contact is confirmed by the contact with a monitor needle 2; and the pressure 5 is read out at a point of an optimum contact pressure. A good-product initial data is first stored by said measuring method. Then, an automatic prober is actuated automatically. Even when the interval (between a probe needle and a wafer) of the probe needle 2 is changed by a change in surroundings, the pressure 5 is exerted on the stage 4, the stage is raised, the good-product stored pressure is exerted after the contact has been confirmed by using the monitor needle 2 and a measuring operation is executed. It is possible to obtain the uniform contact with the surface of a wafer 3.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a wafer properr used for testing semiconductor integrated circuits, and in particular to a semiconductor integrated circuit testing device (hereinafter referred to as a test system) and a semiconductor integrated circuit. electrical contact.

[Conventional technology]

FIG.
(1) is a probe card, (2) is a probe needle, (3)
Fi wafer, (4) is the prober stage, (5) is the test system, Figure 4 (g) is the electrical contact method with the test system (probe needle and wafer), Figure 4 (q is the operation of the wafer prober) , FIG. 4(Φ) shows an example of poor contact, 6) shows dust, and FIG. 4(G) shows the test results.

In the semiconductor integrated circuit whose operation will be explained next, the method of making electrical contact between the test system and the wafer is to place the probe needle on the pad of one chip on the surface of the sea urchin, as shown in Figure 4). The test is performed by inputting a signal to the system chip 1, but the contact between the probe needle (2) and the wafer (3) is determined by inputting the data to the test system of the good chip in the i-Manual before the auto test. Visually check for any scratches on the glove needle pad, fix the probe card and stage, and then fix the probe card and stage as shown in Figure 4 (C).
) After measuring one chip at (c) -1, the stage moves down to C1 (0) at -2.The stage moves below the next chip at (c)-3, and at (c)-4, the stage moves to the bottom. Same as previous chip
This method was to measure the distance increase.

[Problem to be solved by the invention]

Conventional wafer prober equipment is configured as described above, so in one example, dust may enter between the stage of the wafer prober and the wafer. In this case, there was a problem of poor contact in dust-free areas.

The present invention has been developed to solve the above-mentioned problems, and aims to achieve uniform electrical contact between the glove needle and all chips on the wafer surface.

[Means to solve the problem]

The wafer probe in this invention uses a monitor probe needle and pressure to bring the stage into contact with the needle.

[Effect]

The wafer prober of the present invention expresses the contact between the probe needle and the wafer as pressure, so that tests can always be performed with uniform contact.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure shows the principle of the structure of the stage of the wafer prober of the present invention. (1) is a probe card, (2) is a monitor glove needle, (3) is a wafer, (4) is a stage, and (5) is a probe card.
is the pressure, and (6) is the pressure gauge.

In Figure 2, (,) indicates the measurement of an initial good chip, and (b) indicates the measurement when the distance between the glove needle and the wafer has changed due to the environment (connection state between the glove card and the probe needle), etc. (C) is a state in which the stage is raised by pressure, the stage is raised until the monitor needle monitors, pressure is applied, and measurement is performed, and (d) is a flowchart for automatic test (K).

FIG. 3 is an example diagram.

In the structure of the Queha prober of the present invention, when the stage and the probe needle are brought into contact, as shown in FIG. The feature is that the pressure is increased from the point where V is applied, and the pressure (stylus pressure) is read and memorized at the optimal contact pressure point.

Next, the operation will be explained. First, as shown in FIG. 2 (-, according to the same measurement method as above), the initial data of non-defective products is stored. Next, the autoprober is operated automatically. Even if the distance between the probe needle and the wafer (probe needle and wafer) changes due to changes in the environment, as shown in Figure 2 (C),
Pressure is applied to the stage and the stage rises, and after confirming contact with a monitor needle, uniform contact can be obtained on the wafer surface by applying pressure to memorize good products and performing measurement.

FIG. 3 shows one embodiment, in which the structure is similar to a piston in a car, and the same structure as above is used for the rotating shaft to perform control.

The same structure can also be implemented in the handler.

〔Effect of the invention〕

As described above, by making the contact between the glove card and the wafer uniform according to the invention of the first century, it is possible to avoid defects due to changes in the contact state, and thus an improvement in yield is expected.

[Brief explanation of drawings]

Fig. 1 is a principle diagram of an embodiment of the present invention, Fig. 2 is an operation diagram and flowchart of Fig. 1, Fig. 3 is a configuration diagram of an embodiment of the invention, and Fig. 4 explains a conventional wafer probe. FIG. In the figure, (1) is a probe card, (2) is a monitor probe needle, (3) is a wafer, (4) is a stage, (5) is a pressure, and (6) is a pressure gauge. In addition, in the figures, the same symbols indicate the same or corresponding parts.

Claims (1)

[Claims] In a wafer prober device for testing semiconductor integrated circuits in their wafer state, probe needles and IC
In order to maintain uniform electrical contact with the electrode pads of the chips for all chips on the IC wafer, a monitor is installed on the probe needle to apply a force that pushes up the stage of the prober on which the IC wafer is placed perpendicular to the probe needle. Confirm the contact with the wafer using a monitor, then raise the stage to the optimal contact between the probe needle and the stage, store the increased pressure as good product pressure data, and use the above data to determine whether all chips are in contact with the wafer. A wafer prober is characterized in that it can uniformly contact the entire wafer surface by applying pressure according to the above-mentioned good product pressure data after confirming contact with a monitor needle.