JPS5934641A - Measuring method for characteristic of semiconductor element - Google Patents

Abstract

PURPOSE:To improve the working ratio of a device largely, to reduce the floor area and to enhance yield by protrusively forming probe needle groups to both surfaces of one probe card and alternately measuring the characteristics of the elements of two wafers. CONSTITUTION:Three of the probe card 10, both surfaces thereof have the probe needle groups 11, 12, and two stages 14, 15 holding two wafers 16, 17 while making the wafers oppose in parallel to both surfaces of the probe card 10 are intermittently moved relatively in the parallel and vertical directions. The two probe needle groups 11, 12 of the probe card are wired to one tester 13, and the position of one of the two stages 14, 15 is moved during a time when the element of the wafer on the other stage is in contact with one probe needle group and its characteristic is measured, thus shortening the waiting time of the tester 13, then largely improving an index. When a defective discriminating mark is put on the surface of the element, ink and chips by scratching flaws flyaway, but they are removed without falling on the wafers because the wafers are arranged vertically.

Description

[Detailed Description of the Invention] Technical Field This invention relates to a method for individually measuring the characteristics of a large number of semiconductor elements formed in alignment on a semiconductor wafer. O Concerning improvement of a method for measuring characteristics by electrically contacting semiconductor elements of a held semiconductor wafer one by one Background technology Normally, characteristics of semiconductor elements such as transistors and ICs are measured by measuring a plurality of semiconductor elements on one semiconductor wafer at once. This is done at the stage when it is formed. This type of semiconductor device characteristic measurement is 1
A common method is to use a probe card having a group of probe needles in a pattern that comes into contact with a group of surface electrodes of one semiconductor element, and a conventional example thereof will be explained using a specific device shown in FIGS. 1 and 2.

In Figures 1 and 2, (1) is a semiconductor wafer (
(hereinafter simply referred to as wafer), (2) is wafer (1)
(3) is a movable stage that holds the wafer (1) horizontally on its upper surface; (4) is the stage (3);
This is a stage drive control unit that moves the stage intermittently up and down in two directions, horizontal X1Y directions and perpendicular directions. (5) is a horizontal probe card fixedly placed above the stage (3), and (6) is a tester (A) that supports the probe card (5) and incorporates an external characteristic measurement circuit. It is a socket for wiring. The probe card (5) is 1 in the center.
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 center downward. Each probe needle is formed in a pattern in which the tip contacts each surface electrode of one semiconductor element (2), and each probe needle is connected to a tester through a probe card (5) and a socket (6). (7) is wired.

In the characteristic measurement operation using the above device, first, the wafer (1) on the stage (3) is not 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). Sequentially, the surface electrode group of the element (2) is brought into contact with the probe needle group (9) and the tester (7
) to measure the characteristics. 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 bottle that scratches the surface of the defective element is used as a means for forming this defective identification mark, and these pens and bottles are placed above the window hole (8) of the probe card (5). It waits, and when a defective element arrives, it descends and attaches a defect identification mark. Such a defective identification mark is used in a subsequent process to classify the elements (2) into good and defective products. Furthermore, instead of attaching a defective identification mark to a defective element, it has recently been practiced to store the value tW for the wafer (1) of the defective element in a microcomputer, and to perform subsequent selection processing based on this stored content.

By the way, if the measurement time required for the tester (7) to measure the characteristics of one element (2) is T, then the above device
The 11 works are repeated as shown in the time chart shown in the figure. That is,
After the measurement of one element (2) is completed, the stage (3) is lowered by a fixed pitch, moved laterally by a fixed pitch, and then raised by a fixed pitch to start measuring the next element (2). During this stage movement, the tester (7) does not operate and waits, and this waiting time W is about 0.3 to 0.5 seconds. ) It took a long time to complete all characteristic measurements, making it 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.
There is a tester in which two probe cards are wired to one tester, and one set measures the characteristics of elements on one wafer while the other set 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 is a problem in that it takes a lot of time to align the upper wafer and the probe card, and it is not very effective in shortening the overall working time.

In addition, if a probe card is installed above a horizontal stage and a mark is placed on the surface of a defective element to identify the defect, ink and scratches may be deposited on the elements surrounding the defective element when marking the surface of the defective element. There is a problem in that the element scatters, falls and adheres to the element, and even if the element is a good one, it becomes a defective one.Therefore, there has been a demand for an improvement measure.

DISCLOSURE OF THE INVENTION The present invention has been made in view of these conventional problems, and includes a probe card in which groups of probe needles are provided protruding from both sides of one probe card to alternately measure characteristics of elements on two wafers. A method for measuring semiconductor device characteristics is provided.

The present invention provides a probe card having a group of probe needles on both sides, and a total of two stage champions that hold a total of two wafers facing each other in parallel to both sides of the probe card, and relatively intermittently in the parallel and perpendicular directions. This is done by moving.

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 wait time for testers and significantly improves the index. The most effective arrangement for the above-mentioned king is a vertical arrangement in which all three are arranged vertically, but even if they are arranged horizontally horizontally, the index-like effect will not change.

BEST MODE FOR CARRYING OUT THE INVENTION A specific example of an apparatus for implementing the present invention in which the above-mentioned kings are vertically arranged is shown in the fourth example.
As shown in the figure, 00) is one probe card that is tilted vertically (before being fixed), and (U) and (B) are two first and second probe needles protruding from both sides of the probe card (10). Group, 03) is the first and second probe needle group (l
This is one tester for wiring υμs). H and α5
) are two movable acid first and second stages arranged parallel to each other on both sides of the probe card, and one wafer (16) (1°?) is attached to each inner surface by means such as vacuum suction. Each wafer (16 bars x 7) is held by a probe card α
0) parallel to both sides.

In (18) and (19), each stage a → (15) is independently intermittently fed in the vertical direction and in the horizontal direction perpendicular to the probe card 00), and each wafer (1
6) A stage drive control unit that sequentially sends each element 1120) (21) of (17) to a measurement position in contact with each corresponding probe needle group (11) (+2).

The apparatus shown in FIG. 4 performs measurement operations in accordance with the time chart shown in FIG. First, set the wafers (16) (17) on the first and second stages θ (15), and
) (17) to the probe card α mark.

This alignment can be performed simultaneously and easily since both wafers (16) α7) face both sides of the probe card θ0). In the measurement operation, for example, first, the first stage 0 → is sent at a fixed pitch in the direction of the probe card 00), and the surface electrode group of one element of the wafer 806 is brought into contact with the first blow needle group (11). Measure the characteristics of the lever element (goods). After the measurement is completed, the first stage 04) is separated from the probe card (1 (IT), and at the same time the second stage 05) is sent at a fixed pitch in the direction of the probe card (lO) to move to one element of another wafer α7). is brought into contact with the second probe needle group (b) to measure the characteristics. During this measurement time, the first stage (14) is moved to a position where the next element 0) faces the first probe needle (11) and is kept on standby. At the point when the second stage (15) leaves the probe card (]0) after the characteristic measurement of the element current υ by the second probe needle (b) is completed, the first stage 0
4) is brought close to the probe card (JO) again to measure the characteristics of the second element O), and during this time the second stage (1
5) is moved to a position 1θ where the next element υ faces the second probe needle group (b) and is kept on standby. After that, repeat the above operation until the first and second probe needles are 0υ(
By doing so, the tester (13) can perform the medullary measurements of the element continuously without waiting time, and the work efficiency is maximized.

Let us consider a case where a mark is attached to the surface of an element whose measurement result is found to be defective in the above operation, indicating the order of failure. 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 a bottle for marking the farewell mark may be housed in a thicker probe card. Furthermore, if the location of a defective confectionery is to be stored in a microcomputer instead of attaching a defective identification mark to a defective element, the probe card may be made sufficiently thin.

The above-mentioned vertical arrangement structure allows the installation floor area of one probe needle and two stages to be reduced, and also makes it easy to control the horizontal movement of the comparatively heavy stage. However, it is also possible to arrange the probe card 00) and each stage 05) horizontally in a horizontal arrangement as shown in FIG.

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 of both m1 of the probe card measure the characteristics of the element alternately without waiting time.5, so the operating rate of the characteristic measuring device can be greatly improved, and the index can be improved. can. In addition, it is possible to arrange the probe card and each stage vertically, which reduces the floor space of the entire equipment and also improves yield by preventing marking debris from falling onto the wafer. improves.

[Brief explanation of the drawing]

Figures 1 and 2 are a plan view and a side view of essential parts showing an example of a conventional method for measuring the characteristics of a cattle conductor element, and Figure 6 is a
FIG. 4 is a side view of a main part showing a specific example of an apparatus for carrying out the method of the present invention, and FIG. 5 is an operation time chart of the apparatus shown in FIG. 00)...Probe card, (1υ, (12)...
Probe needle group, O slope... 1st stage, (b)
)...2nd stage, '(i6), (17)...
Semiconductor wafer, -1@υ...semiconductor element. G (Figure snoring 2 Figure 3v 4 1d l)

Claims (1)

[Claims] (1) A method for individually measuring the characteristics of a plurality of semiconductor elements formed on a semiconductor wafer 71, in which a single probe card is provided with a group of nog-turn probe needles protruding from both sides that come into contact with the surface electrodes of the semiconductor elements. Then, two first and second stages that hold semiconductor wafers are arranged so that both sides of the probe card face each other, and the probe card is placed on the first stage.
, the semiconductor wafers of the first and second stages are alternately moved close to each probe needle group on both sides of the probe card by intermittently moving back and forth between the second stages.
A method for measuring characteristics of a semiconductor device, characterized in that characteristics of a semiconductor device on a semiconductor wafer 1 of a stage are continuously measured.