JPH0236545A - Measuring device for semiconductor element - Google Patents

Abstract

PURPOSE:To remove Si dusts, which are generated by irradiation with a laser beam, and to make it possible to measure stably the electrical characteristics of semiconductor pellets by a method wherein a measuring device is provided with a laser beam irradiation mechanism to put a defective mark on a defective semiconductor element and a mechanism to remove fused matters which are generated by irradiation with the laser beam. CONSTITUTION:A probe card 4 makes it probes 5 and 5' come into contact to electrode terminals 3 and 3' of semiconductor pellets 2, 2' and 2'' and the transfer of a signal is performed among said pellets 2, 2' and 2''. A measuring device is provided with a laser beam irradiation mechanism 6, which directs a laser beam 7 on a defective semiconductor pellet to put defective mark on the defective semiconductor pellet, and an Si dust removing mechanism 8, which is provided with a nozzle 8a to be arranged directly over the irradiation position of the beam 7 and sucks dusts which are generated by irradiation with the laser beam. As the Si dusts, which are generated by irradiation with the laser beam 7, are removed by the mechanism 8, the dusts are hardly adhered on the probes 5 and 5' of the card 4 and the surfaces of the adjacent pellets and a measurement of the semiconductor pellets can be conducted stably.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for measuring electrical characteristics of a semiconductor element formed on a semiconductor substrate.

[Conventional technology]

To manufacture a semiconductor device, first, impurities are diffused into a semiconductor substrate to form multiple circuit elements such as resistors, diodes, and transistors, each circuit element is wired with a conductive film, and multiple semiconductor elements (hereinafter referred to as semiconductor pellets) are formed. A semiconductor substrate (hereinafter referred to as a semiconductor wafer) including a semiconductor substrate (hereinafter referred to as a semiconductor wafer) is formed. Next, the electrical characteristics of the semiconductor pellets are measured using an LSI tester in the state of a semiconductor wafer, the semiconductor pellets are sorted, and defective semiconductor pellets are marked with a defect mark (dot).

In this method of sorting semiconductor pellets, a probe of a probe card formed to face the electrode terminal of the semiconductor pellet is brought into contact with the electrode terminal of the semiconductor pellet, and measurement is performed according to a test program stored in advance in an LSI tester. After completion, if the pellet is found to be defective, marks such as scratches and ink are placed on the surface of the defective pellet, and the electrical characteristics of the semiconductor pellet are measured and the defective pellets are marked individually.

Methods for marking defective pellets include an ink coating method in which ink is applied to the surface of the semiconductor pellet, a scratch dotting method in which the surface of the semiconductor pellet is scratched with a thin wire made of stainless steel, and a laser beam is irradiated to form depressions on the surface of the semiconductor pellet. There is a laser beam dotting method, and the laser beam dotting method tends to be used more often because it is easy to work with and the marks are easy to identify.

FIG. 3 shows a conventional measuring device.

The probes 5, 5' of the probe card 4 are in contact with the electrode terminals 3, 3' of the semiconductor wafer 1 containing a plurality of semiconductor pellets 2.2', 2', and are connected to an LSI tester (not shown in the figure). Connect the LSI through the connection cable (omitted in the diagram)
The tester, the probe of the probe card, and the electrode terminal of the semiconductor pellet are electrically connected.

The electrical characteristics of the semiconductor pellet 2 are tested according to a test program stored in the LSI tester in advance. If the measurement results are defective, a laser beam 7 is irradiated from the laser beam irradiation mechanism 6 onto the surface of the semiconductor pellet to melt the semiconductor substrate and form a depression to mark the semiconductor pellet as defective.

While moving the probe card or semiconductor wafer,
The electrical characteristics of each semiconductor pellet are inspected and defective pellets are marked.

[Problem to be solved by the invention]

However, conventionally, when a semiconductor substrate is irradiated with a laser beam to melt a semiconductor substrate and form a depression on the pellet surface, a molten material (Si<) is generated and the probes 5, 5 of the probe card are
Si<> easily adheres to the tips of the pellets 2', and furthermore, this Si> easily adheres to the surfaces of the adjacent pellets 2', 2'.

This phenomenon of adhesion of Si < is more likely to occur as the number of probes increases, or when the distance from the laser beam irradiation position (marking position) to the probe is short. This means that the greater the number of electrode terminals on a semiconductor pellet, or the smaller the size of a semiconductor pellet, the more likely Si<<> is to adhere. Si<Zuga probe card probe 5,
5', when measuring the next semiconductor pellet 2' or 2', the contact resistance between the probe 5.5' and the electrode terminal increases, resulting in a voltage drop when current is applied from the LSI tester. increases, and as a result, there is a risk that non-defective pellets will be judged as defective.

Furthermore, if Si<> adheres to the surface of adjacent pellets, it tends to cause a poor appearance, or this Si (<<>>) straddles between the wirings of the semiconductor pellets, causing electrical short-circuits between the wirings and resulting in poor electrical characteristics.

As a solution to the above-mentioned problem of increased contact resistance of the probe card tips, a method has been implemented in which the tips of the probe card are polished every time several semiconductor wafers are measured, but this method has the following problems and cannot be completed completely. However, it has no effect on the problem of Si<> adhering to the surfaces of adjacent pellets. That is, there are disadvantages such as: (1) the workability of semiconductor pellet sorting is significantly reduced; (2) the tips of the probe card are severely worn; and (2) the Si adhered to the probes cannot be completely removed.

An object of the present invention is to provide a semiconductor device measuring device that solves the above problems.

[Differences between the invention and the prior art]

The present invention differs from the conventional apparatus described above in that it removes the melted material of the semiconductor substrate generated by laser beam irradiation.

[Means to solve the problem]

To achieve the above object, the present invention provides an apparatus for measuring the electrical characteristics of a plurality of semiconductor elements formed on a semiconductor substrate, which includes a laser beam irradiation mechanism for marking defective semiconductor elements as defective, and a laser beam irradiation mechanism for marking defective semiconductor elements. It has a mechanism for removing melt generated by irradiation.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

(Example 1) FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

In the figure, a plurality of semiconductor pellets 2.2', 2' are formed on a semiconductor wafer 1, and each semiconductor pellet 2.2' is formed on a semiconductor wafer 1.
Electrode terminals 3 and 3' of ' and 2' are provided on the front side of the semiconductor wafer 1. The probe card 4 has its probe 5,
5' to semiconductor pellet 2.2', 2' electrode terminal 3.3
', and sends and receives signals between the semiconductor pellets 2.2' and 2'.

The present invention includes a laser beam irradiation mechanism 6 that irradiates a defective semiconductor pellet with a laser beam 7 to mark a defective semiconductor pellet;
A nozzle 8a is disposed directly above the irradiation position of the laser beam 7, and is equipped with a Si removal mechanism 8 that sucks dust generated by the laser beam irradiation.

According to the present invention, since the Si<> generated by the irradiation with the laser beam 7 is removed from the Si<< removal mechanism 8,
This has the advantage that it hardly adheres to the surfaces of the probes 5, 5' of the probe card 4 and the adjacent pellets, making it possible to stably measure semiconductor pellets.

(Example 2) FIG. 2 is a configuration diagram showing a second embodiment of the present invention.

In this embodiment, the nozzle 8a of the Si<> removal mechanism 8 is opened near the probes 5, 5' of the probe card 4.

According to this embodiment, since the nozzle 8a is located near the probes 5, 5' of the probe card 4, there is an advantage that adhesion of SL to the probes 5, 5' of the probe card 4 and the surfaces of adjacent pellets can be prevented. There is.

〔Effect of the invention〕

As explained above, the present invention removes Si<< generated by laser beam irradiation in measuring the electrical characteristics of semiconductor pellets using the laser beam dotting method.
The electrical properties of semiconductor pellets can be measured stably.

The present invention is more effective as the number of probes in the probe card increases and the size of the semiconductor pellet is smaller. Its value is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of the present invention, FIG. 2 is a block diagram showing a second embodiment of the present invention, and FIG. 3 is a block diagram showing a conventional example. 1... Semiconductor wafer 2... Semiconductor pellet 3.3'... Electrode terminal 4... Probe card 5.5'... Probe 6... Laser beam irradiation mechanism 7... Laser beam 8...Si
Patent applicant for removal mechanism: NEC Corporation/・Half 4 body 7r, bar 22:2” Sheep 44 Rei Pele, 7 to 33 pa, Gokusakko 4, Brouf original-F 5.5′・Ring material 5 Go to the Racer Hime Book 7 page 7. Mechanism Figure 1 Figure 3

Claims (1)

[Claims] (1) In a device that measures the electrical characteristics of multiple semiconductor elements formed on a semiconductor substrate, there is a laser beam irradiation mechanism that marks defective semiconductor elements as defective and removes melts generated by laser beam irradiation. 1. A semiconductor device measuring device characterized by having a mechanism for: