JPH038584B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a method for individually measuring the characteristics of a large number of semiconductor elements formed in alignment on a semiconductor wafer. The present invention relates to an improvement in a method for measuring characteristics in which semiconductor elements of a held semiconductor wafer are brought into electrical contact one by one.

BACKGROUND ART Characteristics of semiconductor elements such as transistors and ICs are usually measured after a plurality of semiconductor elements are formed on a single semiconductor wafer. This type of semiconductor device characteristic measurement is generally carried out using a probe card that has a pattern of probe needles that come into contact with the surface electrodes of one semiconductor device. A specific device will also be explained.

1 and 2, 1 is a semiconductor wafer (hereinafter simply referred to as a wafer), 2 is a wafer 1
A plurality of semiconductor elements (hereinafter simply referred to as elements) are arranged in rows and columns, 3 is a movable stage that holds the wafer 1 horizontally on its upper surface, and 4 is a stage 3.
This is a stage drive control unit that moves the stage intermittently up and down in the horizontal X and Y directions and the vertical Z direction. 5 is a horizontal probe card fixedly arranged above the stage 3, and 6 is a socket for supporting the probe card 5 and electrically wiring it to a tester 7 incorporating an external characteristic measuring circuit. probe card 5
has one window hole 8 in the center, and a probe needle group 9 consisting of a plurality of probe needles is provided protruding from the periphery of the window hole 8 toward the lower part of the center. Each probe needle is formed in a pattern in which its tip abuts each surface electrode of one semiconductor element 2, and each probe needle is wired to a tester 7 via a probe card 5 and a socket 6.

In the characteristic measuring operation by the above apparatus, first, the wafer 1 on the stage 3 is aligned with the probe card 5. Next, the stage 3 is moved intermittently in the X, Y, and Z directions to sequentially feed the elements 2 on the wafer 1 one by one to the measurement position in the center of the probe card 5, and at the measurement position, the surface electrodes of the elements 2 are sequentially moved. is brought into contact with the probe needle group 9 and the characteristics are measured using the tester 7. When the characteristic measurement result of one element 2 is found to be good, the measurement operation of the next element 2 is successively carried out, and when the characteristic measurement result is found to be poor, a defect identification mark is formed on the surface of the defective element. A marking pen that applies ink to the surface of the defective element or a pin that scratches the surface of the defective element is used as means for forming this defective identification mark. When the element arrives, it moves down and attaches a defect identification mark. Such a defective identification mark is used in a later process when the elements 2 are sorted into good and defective products. Furthermore, instead of attaching a defect identification mark to a defective element, it has recently been practiced to store the position of the defective element with respect to the wafer 1 in a microcomputer, and to perform subsequent selection processing based on the stored contents.

By the way, if the measurement time required for the tester 7 to measure the characteristics of one element 2 is T, the above-mentioned apparatus repeats the operation as shown in the time chart shown in FIG. That is, after completing the measurement of one element 2, stage 3
is lowered by a fixed pitch, moved laterally by a fixed pitch, and then raised by a fixed pitch, and measurement of the next element 2 is started. During this stage movement, the tester 7 does not operate and waits, and this waiting time W is approximately 0.3 to 0.5 seconds. It took a long time to complete the process, and it was difficult to improve the index.

As a method to reduce such wasted measurement time, two sets of stages and probe cards similar to those described above are installed in parallel, and the two probe cards are wired to one tester. While measuring the characteristics of the elements on one wafer, another group moves the stage. According to this method, the shared tester operates almost continuously and the waiting time is greatly reduced, but since the two stages are installed side by side, the total installation floor space becomes extremely large, and the two stages There was a problem that it took a lot of time to align the upper wafer and the probe card, and it was not very effective in shortening the overall working time.

In addition, if a probe card is installed above a horizontal stage and a defect identification mark is attached to the surface of a defective element, ink and scratches may be deposited on the elements surrounding the defective element when marking the surface of the defective element. There is an inconvenience that the element scatters, falls and adheres to the element, and even if the element is good, it becomes a defective item, and an improvement measure has been desired.

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and has a structure in which probe needle groups are provided protruding from both sides of one probe card to alternately measure the characteristics of elements on two wafers. A method for measuring semiconductor device characteristics is provided.

The present invention includes a probe card having probe needle groups on both sides, and a total of two wafers that hold two wafers parallel to each other on both sides of the probe card.
This is carried out by intermittently moving the three stages of the stand relatively in parallel and perpendicular directions. The two groups of probe needles on the probe card are wired to one tester, and one of the two stages moves while the elements of the wafer on the other stage are in contact with one group of probe needles to measure their characteristics. However, this reduces tester waiting time and significantly improves the index. The most effective arrangement of the above three is a vertical arrangement in which all three are arranged vertically, but even if they are arranged horizontally and horizontally, the indexing effect remains the same.

BEST MODE FOR CARRYING OUT THE INVENTION FIG. 4 shows a specific example of an apparatus for carrying out the present invention in which the above three components are vertically arranged. 10 is one probe card fixedly arranged in the vertical direction; 11 and 12 are Two first ones protruding from both sides of the probe card 10,
The second probe needle group 13 is one tester for wiring the first and second probe needle groups 11 and 12. 14 and 15 are probe cards 10
Two movable first and second stages are arranged parallel to each other on both sides of the
The wafers 6 and 17 are held by means such as vacuum suction, and each wafer 16 and 17 faces both surfaces of the probe card 10 in parallel. 18 and 19 are each stage 14,
15 independently in the vertical direction and the probe card 10
The elements 20 and 21 of each of the wafers 16 and 17 are intermittently fed in the vertical and horizontal directions perpendicular to the horizontal direction.
This is a stage drive control unit that sequentially sends the probe needles to the measurement positions where they come into contact with the corresponding probe needle groups 11 and 12.

The apparatus shown in FIG. 4 performs measurement operations in accordance with the time chart shown in FIG. First, 1st and 2nd stage 1
The wafers 16 and 17 are set on the probe cards 4 and 15, and the wafers 16 and 17 are aligned with the probe card 10. This alignment can be performed simultaneously and easily since both wafers 16 and 17 face both sides of the probe card 10. For example, the measurement operation starts with the first
The stage 14 is moved at a fixed pitch in the direction of the probe card 10 to bring the surface electrode group of one element 20 of the wafer 16 into contact with the first probe needle group 11 to measure the characteristics of this element 20. When the measurement is completed, the first stage 14 is separated from the probe card 10, and at the same time, the second stage 15 is moved in the direction of the probe card 10 by a fixed pitch to transfer another wafer 17.
one element 21 of the second probe needle group 1
2 to measure the characteristics. During this measurement time, the first stage 14 is moved to a position where the next element 20 faces the first probe needle 11 and is kept on standby. After the characteristic measurement of the element 21 by the second probe needle 12 is completed, the second stage 1
5 leaves the probe card 10, the first stage 14 is brought close to the probe card 10 again and the characteristics of the second element 20 are measured.
The stage 15 is moved to a position where the next element 21 faces the second probe needle group 12 and is kept on standby. After that, repeat the above operation, and
The characteristics of the elements 20 and 21 are measured alternately using the probe needles 11 and 12. In this way, the tester 13 continuously measures the characteristics of the elements without waiting time, and the work efficiency is maximized.

For elements whose measurement results are found to be defective in the above operation,
Consider the case where a defect identification mark is attached to the surface of the element. At this time, the ink and scratches fly away due to the marking operation, but since the wafer is arranged vertically, this is removed without falling onto the wafer, so the good devices around the defective devices are safe. . A marker such as a pen or pin for marking a defective identification mark may be housed in a thicker probe card. Furthermore, if the position of the defective element is to be stored in the microcomputer instead of attaching a defective identification mark to the defective element, the probe card may be made sufficiently thin.

By using the above vertical arrangement structure, the installation floor space for one probe needle and two stages can be reduced.
Further, although the horizontal movement of a relatively heavy stage can be easily controlled, the present invention is not limited to this example of vertical arrangement, but the present invention is also applicable to a horizontal arrangement in which the probe card 10 and each stage 14, 15 are horizontally arranged as shown in FIG. It is also possible to have a structure of

Further, the present invention can be implemented by using a structure in which two stages are fixed or semi-fixed and the probe card side is moved back and forth between the two stages.

As described above, according to the present invention, the probe needle groups on both sides of the probe card alternately measure the characteristics of the elements without waiting time, so that the operating rate of the characteristic measuring device can be greatly improved and the index can be improved. In addition, the probe card and each stage can be arranged vertically, which reduces the floor space of the entire device and prevents marking debris from falling onto the wafer, improving yield. .

[Brief explanation of drawings]

1 and 2 are a plan view and a side view of essential parts showing an example of a semiconductor device characteristic measuring device using a conventional method, FIG. 3 is an operation time chart of the device shown in FIG. 1, and FIG. 4 is a method according to the present invention. FIG. 5 is a side view of a main part showing a specific example of the apparatus for implementation, and FIG. 5 is an operation time chart of the apparatus shown in FIG. 10... Probe card, 11, 12... Probe needle group, 14... First stage, 15...
...Second stage, 16, 17... Semiconductor wafer, 20, 21... Semiconductor element.

Claims (1)

[Claims] 1 A method for individually measuring the characteristics of a plurality of semiconductor elements formed on a semiconductor wafer, which uses one probe card with a group of probe needles protruding from both sides in a pattern that contacts the surface electrodes of the semiconductor elements; Two first and second stages that hold a semiconductor wafer are arranged facing each other on both sides, and the probe card is intermittently moved back and forth between the first and second stages to attach each probe needle group on both sides of the probe card. 1. A method for measuring characteristics of a semiconductor device, characterized in that semiconductor wafers of the first and second stages are alternately brought close to each other, and characteristics of semiconductor devices on the semiconductor wafers of the first and second stages are successively measured.