JPS61171147A - How to check the coordinates of a wafer ham tup - Google Patents

Abstract

PURPOSE:To enable the correction of wafer maps by a method wherein each coordinate is judged whether finished in measurement (state of '1') or unfinished in measurement (state of '0') through inspection of coordinates determined in the direction of advancement of a probe card, and the result is compared with pre-determined patterns of '1' and '0'. CONSTITUTION:In the case of the upward movement of a probe card 12 in the Y-axis, when the coordinate of a chip under measurement is (x, y) in a wafer map 13, chips finished in measurement from among adjacent chips lie each at coordinates (y+1, x-1), (y, x-1), (y-1, x-1), (y-1, x), and chips unfinished in measurement lie each at coordinates (y+1, x+1), (y, x+1), (y-1, x+1), (y+1, x). Therefore, if all the vertically reverse L-shaped patterns are '1' and all of the laterally reverse ones are '0' around a chip under measurement, the result of measured chips is registered at right positions of the wafer map 13, and it is possible to completely inspect the address shift of the wafer map 13.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for inspecting the coordinates of a wafer, and more specifically, a method for inspecting the coordinates of a wafer using a prober, probe card, tester, etc. The present invention relates to a method for checking whether a chip to be measured corresponds to a correct position on a wafer hap during measurement.

[Conventional technology]

In the manufacturing of semiconductor devices, a wafer is divided into many identical dimensions, the same elements are formed in each division, and wafer processing is completed.The wafer is then cut into each division, each division containing one chip. becomes.

When wafer processing is completed, measurements are taken for each section using a probe card to determine whether the devices formed in that section are good or not, and the results are stored in the wafer map. For convenience of explanation, each section of the wafer will be referred to as a chip below, and referring to FIG. 3, each chip 32a, 32b of the wafer 31.

16. The results of the measurements made are stored as 32a, 32b, . . . on the wafer map shown in FIG.

According to the current general measurement method, when the coordinates When the test is finished, move X one place to the right, then measure Y upwards (increasing Y direction), and repeat this process.The test result is either a good product or a defective product, but the diagram shows a simple This is shown with black dots.

By attaching some kind of indication to the defective chips according to the wafer map created in this manner, the defective chips can be easily identified when the wafer is cut into chips.

[Problem that the invention seeks to solve]

When actually creating a wafer map, the wafer map may not be created as described above, and even though the probe card measures as shown in FIG. In other words, the coordinates of the wafer may be shifted. Therefore, when a wafer bump as shown in FIG. 3(C) is obtained, there is a problem in that measurement must be performed again.

(Means for Solving the Problems) The present invention provides a method for inspecting the coordinates of a wafer that solves the above-mentioned problems. When writing on the wafer map, the coordinates of the measurement chip are checked by checking whether the measurement data is included in the L-shaped judgment pattern around the chip, and if there is a coordinate deviation, it is corrected using the L-shaped judgment pattern. This is accomplished by a wafer map coordinate inspection method characterized by the following.

[Effect]

In the above method, the coordinates determined in the direction of movement of the probe card are checked, and it is determined whether each coordinate has been measured (state of 11 degrees) or has not been determined (state of "0"), and the determination result is is compared with a predetermined pattern of "1" and "0" on the front side to determine coordinate deviation, and if there is a coordinate deviation, the measurement result is written in the correct coordinate according to the result of the comparison.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

A wafer map illustrating the implementation of the method of the invention is shown in FIG.

First, referring to Figure 1(a), it shows the case where the probe card moves upward on the Y axis (Y increasing direction).
The coordinates of the chip being measured in the wafer hop are (
IC, y), among the chips adjacent to the chip at the coordinates (x, y), the chips that have already been measured (they have a state of 1" because they contain measurement data) are OFF, respectively.
+11! -1), (3Flx-1), (y
-L
), (yr x+1)-(y-L x+l), (y
rL x). This state is shown in FIG. 1(C), in which the arrow indicates the Y decreasing direction.

On the other hand, the wafer map when the probe card moves downward on the Y axis (Y decreasing direction) is shown in Figures 1~), and at this time, among the chips adjacent to the chip at the coordinates (x, y), the Each finished (11”) chip is (711X2)
l (yr X2)l ()' 2 + "2)
+ (711X), unmeasured (“O′”
) chips are (71+Xl)+(yrxt) respectively
(72y xl) + (y2 * x) (to avoid confusion with the case in Figure 1(a), x
, y increases by X1+71, and decreases in x and y by X2+72). This state is shown in FIG. 1(d), in which the arrow indicates the Y increasing direction.

From the patterns in Fig. 1(C) and (d), the patterns in Fig. 1(e) and (
A basically 5-shaped determination pattern shown in f) is obtained. When Y is in the decreasing direction, if the upside-down 5-shaped pattern around the chip under measurement is all "1", and the left-right upside down 5-shaped pattern is 60", The result of the measurement chip will be written in the correct position on the wafer map.

When Y is in the increasing direction, the determination pattern of "1" is a 5-character pattern, and the determination pattern of "0" is a 5-character pattern inverted vertically and horizontally.

In this way, by checking the "1" judgment pattern and the "01 judgment pattern," it is possible to completely check the address (coordinate) deviation of the wafer happe, and each measurement chip is also inspected. It is also possible to correct misaligned addresses.

To carry out the above method, referring to the block diagram of FIG. 2, coordinate data is sent from the prober 11 to the tester 14, a wafer map is created, and the tester 14 stores the coordinate data. The results of measuring the chips on the wafer 13 with the probe card 12 are also input to the tester 14 . When the probe card comes to the chip at certain coordinates (x, y), tester 1
The wafer map is scanned according to the 5-shaped pattern described above in 4. If the signals of '1' and ``0'' match the 5-shaped pattern, it is measured, and if they deviate, necessary corrections are made.

Note that the above explanation was about increases and decreases in the Y direction, but the method of the present invention deals with increases and decreases in the X direction.

In the case of reduction, it can be carried out in exactly the same way.

〔Effect of the invention〕

As explained above, according to the present invention, the measurement chip coordinates (
By using the L-shaped determination pattern, you can check the addresses of the chips around the wafer ham (address), so if a coordinate shift occurs, you can correct the wafer ham and continue measurement. This has the effect of improving reliability.

[Brief explanation of the drawing]

Figure 1 (a+ and (bl are diagrams showing the wafer hamps around the measurement chip, Figures (C) and (d) are diagrams showing measured and unmeasured states corresponding to (a) and inside), Figure 1 (e) and (fl
are diagrams of determination patterns based on (C) and (dl, Figure 2 is a block diagram of a system implementing the method of the present invention, and Figure 3 is a diagram of (
(a) is a plan view showing the chips of the wafer; (in the same figure) is (a)
(C1 is a diagram of a wafer map that was made incorrectly. In the diagram, 11 is a prober, 12 is a probe card, 13 is a wafer, and 14 is a tester. 1 Figure 1 Figure 2 Figure J 3rd FIl

Claims (1)

[Claims] When measuring a wafer using a prober, probe card, and tester and writing the results to a wafer map,
A wafer characterized in that the coordinates of a measurement chip are checked by checking whether measurement data is included in an L-shaped determination pattern around the chip, and if there is a coordinate deviation, the coordinates are corrected using the L-shaped determination pattern. How to check map coordinates.