JP2817673B2 - Testing method of probe card and IC chip - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for testing a probe card and an IC chip used in an IC wafer test.

[0002]

2. Description of the Related Art When measuring electrical characteristics of a large number of IC chips formed on an IC wafer, a measurement probe attached to a probe card is attached to each of a plurality of electrode pads (bonding pads) on the surface of the IC chip. This is performed by bringing a needle (probe) into contact, applying an electric signal to the IC chip through the plurality of measurement probes, and connecting to an IC tester that receives a response signal from the IC chip and measures electric characteristics.

Here, it is preferable to measure a plurality of IC chips at the same time in order to reduce the measurement cost.

However, when electrode pads are arranged along four sides of an IC chip to be measured, it is difficult to set a measuring probe to each electrode pad of the IC chip adjacent to the side. Become.

[0005] Japanese Patent Application Laid-Open No. Hei 4-330748 discloses a structure in which a measuring probe is set up for each of IC chips adjacent to each other in an oblique direction.

FIG. 4 is a diagram showing a probe card for probing two IC chips adjacent to each other in an oblique direction. In the same figure, the IC to be measured is located
A plurality of probe needles (not shown) supported on the upper surface of the needle stand 5 are inclined downward in the opening 6 so that each of the IC chips located in the squares a and b is located. The electrode pad is arranged so that the tip can be brought into contact with the electrode pad.

FIG. 5 shows that the number of simultaneous measurements is increased to four in order to further reduce the measurement cost. Quadrilateral a, quadrilateral b, and quadrilateral c, each of which represents a virtual chip with diagonal lines. And the quadrilaterals d are arranged in an oblique linear direction, and a number of probe needles (not shown) supported on the upper surface of the needle stand 5 are inclined downward in the opening 6 to form quadrangles a, b, c, and d
Are arranged such that the tips thereof can be brought into contact with the respective electrode pads of the IC chip located at the respective positions. This constitutes a probe card for probing four IC chips simultaneously.

FIG. 6 shows a method of measuring an IC chip on an actual IC wafer using this probe card.
It is.

First, each of the quadrilaterals a, b, c and d in FIG.
Respectively correspond to A, B, C and D in FIG. Also, a direction parallel to the orientation flat of the IC wafer 12 will be described as a column direction, and a direction perpendicular thereto will be described as a row direction.

First, at a probing start point 13 ', an IC chip D corresponding to a quadrilateral d is probed. In this example, there are no IC chips corresponding to the quadrangles a to c. When the measurement at the starting point 13 'is completed, the IC chip moves relatively in the direction of the arrow to measure the IC chip adjacent to the right side in the column direction. Also in this case, only the IC chip D corresponding to the quadrilateral d is measured. Next, when measuring an IC chip adjacent to the right side, IC chips D and C corresponding to the quadrilateral d and the quadrilateral c are measured. When the measurement at that position is completed in this manner, the measurement is performed while moving relatively by one IC chip to the right in the figure and shifting in the direction of the arrow.

At the probing intermediate point 14 ', an IC chip A corresponding to the quadrilateral a (the upper right end is missing)
In the figure, there are no IC chips in the right direction in the figure, so that four IC chips are moved in the row direction and relatively moved downward in the direction of the arrow in the figure, and a quadrilateral is formed at the probing middle point 15 '. An IC chip A corresponding to a is measured. At this position, there is no IC chip corresponding to the squares b to d.

After the measurement of the probing halfway point 15 'is completed,
Move relatively in the direction of the arrow, one IC leftward in the figure
The chip array is shifted and the measurement is performed. After the measurement at the probing halfway point 16 'is completed, the four IC chip rows are relatively moved again in the direction of the arrow and shifted downward in the figure, and the probing halfway point 17' is started. At the end of the probing, when the measurement at the probing end point 18 'is completed, the probing of the IC wafer is completed. .

When a plurality of simultaneous measurement probe cards are used in this manner, the I
Since the measurement is performed by moving one C chip at a time in parallel in the row direction (vertical direction in the drawing), the test time can be greatly reduced.

[0014]

In a conventional test using probe cards arranged obliquely in a straight line, an IC chip to be actually measured (hereinafter referred to as an effective IC chip) in probing at both ends in the column direction on an IC wafer. ) Is low in that it is unlikely that a plurality of samples can be measured simultaneously. Since the IC wafer has quadrangular IC chips on a circular shape, the position of the effective IC chip is complicated in the peripheral portion.

For the sake of simplicity, assume that four lines, ten lines,
Consider an IC wafer having only rows of valid IC chips. In this case, there are three chances that the quadrilateral of the probe card does not encounter the IC valid chip, and the three tests are not effective, and the test time is extended.

Further, in the method of arranging obliquely in a straight line,
The entire needle stand becomes large. For example, assuming that the size of the IC chip is 10 mm × 10 mm, at least 40 m
An area of mx 40 mm is required.

Accordingly, an object of the present invention is to provide a probe card and a probe card which can increase the probability of encountering an effective IC chip at both ends in the column direction of the IC wafer, reduce the test time, and reduce the area of the needle portion. IC chip
Is to provide a test method .

[0018]

In order to achieve the above object, a feature of the present invention is that a probe card used for an IC wafer test has a structure in which a measurement probe is set up from both upper and lower surfaces of a probe card substrate. , The first to fourth IC chips capable of measuring simultaneously are arranged in one direction.
And alternately in a direction perpendicular to this direction.
Ri probe card having a structure comprising a checkerboard-like arrangement
It is in. Another feature of the present invention is that the orientation of the IC wafer is
Column direction parallel to the orientation flat and straight
A large number of IC chips arranged in a matrix in the row direction of the corner
IC for testing each of the chips with a probe card
Simultaneous measurement in chip test method
The first to fourth IC chips that can be formed are arranged in rows and in columns.
In a checkered pattern.
The first group of IC cards
Of the effective IC chip at one end in the column direction
The effective IC chip at the other end can be measured from
The probe card in the first direction in the row direction
The first group of IC chips located there while moving
And then move the probe card in the row direction.
A second group of IC chips that are moved and do not belong to the first group
Of the effective IC chips on the other end in the column direction
From which a valid IC chip at one end can be measured.
The probe card to the first position in the row direction
The said located there while moving in the opposite second direction
IC chip testing method for testing a second group of IC chips
In the law.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing a probe card according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line AA in FIG. This embodiment is an example of measuring four IC chips simultaneously.

In FIG. 1, each of the virtual chips a to d is indicated by hatching. The quadrilateral a and the quadrilateral b are adjacent to each other in an oblique direction, and the quadrilateral c and the quadrilateral d are also adjacent to each other in an oblique direction. Although the quadrilateral b and the quadrilateral c are adjacent to each other, instead of the four being arranged linearly as shown in FIG.
In FIG. 1, they are arranged in a checkered pattern. That is, in FIG.
First to fourth IC chips that can sometimes measure
Are arranged in one direction and alternately arranged in a direction perpendicular to this direction.
The structure becomes a checkerboard pattern by placing
I have.

The probe card substrate 3 is constructed by incorporating the needle stand 5 having an inclined upper surface into the probe card substrate main body 4, and the quadrilateral of the virtual chip is formed in the opening 6 formed by the needle stand 5 and the probe card substrate main body 4. a to d are located.

The probe needles 7 and 8 are attached to the upper surface of the probe card substrate 3, that is, the inclined upper surface of the needle stand 5, and descend along the same surface, and their respective tips are located at predetermined positions of the quadrangles a and b. I do. This predetermined position is the position of the electrode pad of the IC chip to be measured, which comes in the quadrilaterals a and b. Although a plurality of probe needles 7 and 8 are provided according to the number of electrode pads of the IC chip, only one probe needle is shown in the figure.

On the other hand, the probe needles 9 and 10 are attached to the lower surface of the probe card board 3, that is, the lower surface of the needle stand 5, and their respective tips are located at predetermined positions of the quadrangles c and d. This predetermined location is the position of the electrode pad of the IC chip to be measured, which comes in the quadrilaterals c and d.
Also, a plurality of probe needles 9 and 10 are provided according to the number of electrode pads of the IC chip.

The tips of the probe needles 7, 8, 9, 10 are all located at the same height L as shown in FIG.

FIG. 3 shows the order of probing (measurement) using the probe card according to the embodiment of FIG. The IC wafer in Fig. 3 is an effective IC equivalent to Fig. 6.
With chips.

In FIG. 3, as in FIG. 6, the quadrilaterals a,
b, c, and d correspond to A, B, C, and D, respectively. A direction parallel to the orientation flat of the IC wafer 12 will be described as a column direction, and a direction perpendicular thereto will be described as a row direction.

As in FIG. 6, the direction of probing is relatively moved from the probing start point 13 in the direction of the arrow with respect to the column direction, and the IC chip adjacent to the right side in the figure is measured. When reaching the probing middle point 14, that is, the end in the column direction, it moves relative to the row direction by a plurality (in this example, four) in the direction of the arrow and downward in the figure. That point is the probing middle point 15. The probing is performed by moving relatively from the probing midpoint 15 to the left in the column direction with respect to the column direction and reaching the probing midpoint 16, that is, the end in the column direction. (In this example, four probings) In the direction of the arrow, move relatively in the downward direction in the figure to perform probing at the probing halfway point 17, and relative to the column direction from the probing halfway point 17 to the right in the figure. And the probing is performed to reach the probing end point 18.

According to this embodiment, for example, when attention is paid to the quadrilateral a between the probing midpoint 15 and the probing midpoint 16, A corresponding to this is shown in FIG. Is a waste, whereas only one test is wasted.

[0030]

As described above, the probe card according to the present invention has a structure in which a plurality of IC chips capable of simultaneously measuring the probe needles on the upper and lower surfaces of the substrate are arranged in a checkered pattern. By doing so, the probability of encountering an effective IC chip at both ends in the column direction of the IC wafer can be increased, the test time can be reduced, and the area of the needle stand can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view showing a probe card according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a diagram showing the order of probing IC chips on an IC wafer using the probe card according to the embodiment of the present invention.

FIG. 4 is a plan view showing a conventional two parallel probe card.

FIG. 5 is a plan view showing a conventional four parallel probe card.

FIG. 6 shows an IC using the probe card of FIG. 5 of the prior art.
FIG. 3 is a diagram showing a probing order of IC chips on a wafer.

[Explanation of symbols]

3 Probe card substrate 4 Probe card substrate main body 5 Needle stand 6 Opening 7, 8, 9, 10 Probe needle 12 IC wafer 13, 13 'Probing start point 14, 14', 15, 15 ', 16, 16', 17,1
7 'midpoint of probing 18, 18' end of probing

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-238133 (JP, A) JP-A-54-76073 (JP, A) JP-A-6-196537 (JP, A) JP-A 52-760 115188 (JP, A) JP-A-3-278438 (JP, A) JP-A-6-222079 (JP, A) JP-A-7-302820 (JP, A) Japanese Utility Model Application Laid-open No. 57-41657 (JP, U) 58-168137 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 21/66 G01R 1/073 G01R 31/26

Claims (2)

(57) [Claims] In a probe card used for an IC wafer test, a first to fourth IC chips having a structure in which a measurement probe is set up from both upper and lower surfaces of a probe card substrate and capable of performing measurement simultaneously are provided. probe card characterized by having a structure in which a checkerboard-like arrangement by alternately located column becomes <br/> and direction of the direction perpendicular to the one direction. 2. An IC chip test method for testing a plurality of IC chips arranged in a matrix in a column direction parallel to an orientation flat of an IC wafer and in a row direction perpendicular thereto by a probe card. 1st to 4th that can do
A probe card having a structure in which the IC chips of the first group are arranged in a row direction and alternately arranged in a column direction to form a checkered pattern is used. While moving the probe card in the first direction in the column direction from a position where the effective IC chip can be measured to a position where the effective IC chip on the other end can be measured, the first group of IC chips located there is tested. Thereafter, the probe card is moved in the row direction, and one end of the second group of IC chips that does not belong to the first group can be measured from the point where the effective IC chip on the other end in the column direction can be measured. Testing the second group of IC chips located there while moving the probe card in a second direction opposite to the first direction in the column direction until a valid IC chip can be measured. IC chip test method which is characterized in.