JPH03292749A - Inspection device and inspection - Google Patents

Abstract

PURPOSE:To make it possible to verify immediately whether a probing is performed in a normal state or not by a method wherein a check mechanism for checking the contact of probes with electrodes is provided separately from a semiconductor wafer and in a case a state of fail is continuously generated, a probe card is moved to the check mechanism and the contact of the probes with the electrodes is checked. CONSTITUTION:A wafer 3 placed on a main chuck 1 is sucked and fixed, probes 5 of a probe card 6 are made to correspond to a semiconductor element and after the probes are brought face to face with electrodes made to correspond to the probes, a probing is performed. At this time a state of fail is continuously continued a plurality and in case the state of fail is continued a previously set number, the probes 5 are automatically made to stop the electrical contact with the wafer 3 to be measured on the main chuck 1 by the control of a CPU, a dummy wafer 4 fixed temporarily on a subchuck 2 is automatically moved to a position to oppose to the probes 5, the probes are brought into contact with a dummy chip of the wafer 4 and the state of the contact of the probes with the dummy chip is checked.

Description

[Detailed description of the invention] main character and immediacy (Industrial application field) The present invention relates to an inspection device and an inspection method.

(Prior art) In the semiconductor manufacturing process, a tester probe is brought into contact with a completed element on a semiconductor wafer to inspect its electrical characteristics.
It's happening.

This type of probe device is disclosed in Japanese Patent Application Laid-Open No. 63-198345.
As described in many publications such as Japanese Patent Application Laid-open No. 63-207144, there is an inspection section for inspecting the electrical characteristics of a large number of semiconductor elements formed on a semiconductor wafer (hereinafter abbreviated as wafer), and a section for storing the wafer. The apparatus is comprised of a supply device such as a loader that takes out wafers from a cassette 71 and supplies them to the inspection section.

In the probing of the above device, for example, when a defective crystal knob is selected, if a chip is determined to be a fail (defective product), it is common to use a marking device or the like to mark the surface of the fail element to indicate the defect. In this work,
There may be consecutive failure states.

Possible causes of this continuous failure include a defect in the object to be inspected itself, or a case in which the probe electrodes of the probe card, such as probe needles, are not in contact with the electrodes of the object to be inspected, such as an element, at the correct position.

If the above continuous failure occurs, one of the two causes is that the probe needle of the probe card and the electrode of the device under test are not in contact even though they are in the determined position.
Assuming that there is dust attached to the tip of the probe, the tip of the probe is polished, and probing is restarted to inspect the electrical characteristics of the device for defects.

If a series of failures continues after polishing in this manner, conventionally, the process returns to the non-defective elements in the wafer and inspects whether the probe needles of the probe card are normal.

(Problem to be solved by the invention) However, if there are continuous failures from the beginning of probing, there are no non-defective elements, so the probe needle is returned to the non-defective elements as in the conventional method and re-inserted the probe needle to the element determined to be non-defective. It is not possible to contact the product and determine that it is a good product. As a result, it is impossible to determine whether the probe needle is normal or not.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an inspection device that can immediately confirm whether a probe needle is probing in a normal state.

Means for Solving the Problems The present invention provides an inspection apparatus for inspecting characteristics by electrically contacting probe electrodes with electrodes of semiconductor elements formed on a semiconductor wafer, which are separate from the semiconductor wafer. This is an inspection device equipped with a check mechanism to check the contact of the probe electrode.

Furthermore, in the case where a plurality of consecutive failures occur during probing, the probe card is moved to the checking mechanism and a contact check of the probe electrodes is performed.

(Function) The inspection device of the present invention is provided with an electrode near the mounting body on which the semiconductor wafer is placed, which inspects the contact state of the probe needle, for example, an electrode that inspects a constant value when a set current flows.
By bringing the probe needle into contact with this electrode, the contact state of the probe needle of the probe card can be inspected, so that contact failure of the probe needle can be inspected. As a result, it is possible to prevent a good element from being mistaken as defective.

(Embodiment) An embodiment in which the present invention is applied to a probe device for inspecting a wafer will be described in detail with reference to the drawings.

As shown in FIG. 1, the probe device includes a main body 7a and a mounting body movable on the main body, such as a main chat rack.
It consists of a loader section that transports wafers.

An aluminum chuck is fitted onto the upper surface of the main chuck 1. The upper surface of this chamber is provided with grooves, etc., into which the wafer 3 is suctioned and fixed by well-known suction means.

Near the outer periphery of the main chuck 1, for example 1a from the outer periphery
A sub-chuck 2 is provided at a certain distance apart so that a needle inspection plate or the like for polishing the probe needle after probing is placed.

The main chuck 1 and the sub-chuck 2 are movable, for example, movable in the X direction, Y direction, Z direction, or θ direction by a rotary moving means such as a motor.

Further, on the upper surface of the sub-chuck 2, for example, as shown in FIG.
As shown in FIG. 2, suction holes are evenly provided so that a dummy wafer 4 made of aluminum or the like can be temporarily fixed, for example, suctioned.

Since the dummy wafer 4 is used for contact checking of the probe 5, it is not limited to the aluminum used in the embodiment, but is not particularly limited as long as it is a conductive material.

The probe needle 5 is electrically connected to a tester (not shown), etc., and the probe card 6 is fixed by a ring insert member 6b rotatably provided in the head brake 1-6a of the probe device.

Next, the operation of inspecting the tip of the probe needle will be explained.

In the probe device 7, the handling arm (
After positioning the taken-out wafer using a wafer (not shown), the wafer is placed on the main chuck 1. The placed wafer 3 is suctioned and fixed by the suction means provided in the main chuck 1, and then the main chuck 1 starts moving in the X direction, Y direction, Z direction, or θ direction by a known means such as a motor (not shown). The probe needles 5 of the probe card 6 are made to correspond to predetermined semiconductor elements. Then, the operator uses a visual means such as a COD camera to align the probe needle and the electrode corresponding to the probe needle, and then performs probing. If this continues, the probe needle 5 is automatically moved to the main chuck 1 under the control of the CPU.
Electrical contact with the upper target wafer 3 is stopped, and the dummy wafer 4 temporarily fixed to the sub-chuck 2 is automatically moved to a position facing the probe needle.

The probe needle is brought into contact with the dummy chip of the dummy wafer 4, and the contact state of the probe needle is checked.

At this time, if the contact check results are positive,
The failure result of the elements on the wafer 3 inspected immediately before moving the probe needle 5 to the dummy wafer is certain, and based on this result, work such as marking (not shown) is performed.

These results can be stored in memory and displayed on a CRT or the like.

Further, if the contact check with the dummy wafer 4 is defective, the contact state of the probe needles 5 is defective, and therefore the tip of the probe needles 5 is polished or the like. After this, the contact check with the dummy wafer \4 is performed again, and if the contact check is good, the consecutive elements are again probed just before moving the probe needle 5, and the good chips are selected.・Work such as marking only the knobs.

As described above, according to this embodiment, the dummy wafer 4 is provided on the sub-chuck 2 located close to the main chuck 1, and the contact check can be performed with a small amount of movement of the probe card.

Further, even if continuous failures occur during probing at the initial stage of probing, comparison can be made with the dummy wafer 4 even when there is no object to compare with, and the contact state of the probe needles 5 can be accurately grasped.

The present invention is configured as described above, so that even if continuous failures occur during probing, the probe will not touch the test object that is in good bus condition for comparison. Probe contact checks can be performed easily and accurately. Especially when continuous failures occur in the initial stage of probing, a more reliable probe contact check can be performed.

In addition, the probe is not moved to the bus chip position to perform a contact check, and unlike a specific bus chip, it is a dummy wafer that is somewhat large. By being able to perform contact checks based on the location of the person, contact checks can be carried out quickly as accuracy is not required during contact checks.

Furthermore, it is a simple butchik for testing the fi formation, in which a dummy wafer made of a tetraelectric material is provided on the sub-chuck, and has excellent effects such as being easily compatible with conventional probe equipment.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing an embodiment of a probe device according to the present invention, and FIG. 2 is a front view of the same. l Main chuck 2 Sub chuck 3 Object to be inspected 4 - dummy wafer 5 Tip probe probe card (mini

Claims (2)

[Claims] (1) In an inspection device that tests the characteristics by electrically contacting a probe electrode with the electrode of a semiconductor element formed on a semiconductor wafer, a check mechanism is provided to check the contact of the probe electrode separately from the semiconductor wafer. Characteristic inspection equipment. (2) An inspection method characterized by moving the probe card to the check mechanism according to claim 1 and performing a contact check of the probe electrodes when a plurality of consecutive failures occur during probing.