JPH03224246A - Probe device - Google Patents

Abstract

PURPOSE:To prevent imperfect contact between a probe pin and an object to be measured by overdrive, by receiving the pin pressure applied to a probe pin by using a rigid member. CONSTITUTION:A probe pin 15 is brought into contact with an electrode pad of a semiconductor wafer; the chuck top of the wafer is further made to ascend, and overdrive is applied; the pin 15 between a fixed plate 16 and guide plates 19, 20 is buckled and deformed so that a specified pin pressure is applied to the wafer; and thus the electrical contact between the pin and the wafer can excellently be maintained, and measurement of high precision is realized. Since the pressure of the pin 15 is received by a reinforced body 13 and a reinforced ring 2 of high rigidity installed at the lower part of the substrate 12a, the deflection of a probe card can extremely be reduced, and the imperfect contact between the pin 15 and an object to be measured is not generated.

Description

[Detailed description of the invention] purpose of invention (Industrial application field) The present invention relates to a probe device.

(Prior Art) In the manufacturing process of semiconductor devices, in order to measure a large number of chips formed on a semiconductor wafer, as shown in FIG. There is a probe card 3 which is soldered to the semiconductor wafer and whose free end is electrically contacted with the semiconductor wafer. Above probe needle 1
By contacting the electrode pad array of each chip of the semiconductor wafer 4, various electrical characteristics of each chip are measured with a tester.

In this measurement method, after the probe needle contacts the electrode pad array of each chip of the object to be measured, such as a semiconductor wafer, the semiconductor wafer is further raised, an overdrive is applied with a certain amount of upward stroke, and the needle pressure of the probe needle is applied to the probe. Measures are taken to ensure that the needle contacts the semiconductor wafer to avoid contact failure.

(Problems to be Solved by the Invention) However, according to the above technology, the following problems existed.

That is, even if overdrive is applied, there is a drawback that there are many contact failures.

As a result of studies conducted by the present inventors in this regard, for example, when the above-mentioned overdrive amount (0,0) is multiplied by 50 μm, the amount of deflection of the printed circuit board 2 may reach 30 μm. In this case, the actual overdrive amount is 20
Even if the stylus pressure of the probe needle 1 is set to 2gf, the actual stylus pressure will be 0.8gf, and since the actual stylus pressure is lower than the set stylus pressure, the probe needle 1 will not make contact. It was found that defects occurred and only results with low measurement accuracy were obtained.

The present invention was developed in view of the above-mentioned circumstances, and an object of the present invention is to provide a probe device configured such that contact failure does not occur even when overdrive is applied.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a probe device for measuring electrical characteristics by bringing a probe needle into contact with an object to be measured. This is a probe device in which a rigid member receives the needle pressure received by the probe.

Further, the structure of the rigid member is preferably such that a highly rigid metallic reinforcing body is provided at the lower part of the substrate and this reinforcing body is fixed to a part of the device main body via a highly rigid reinforcing ring.

(Function) Therefore, according to the present invention, when measuring an object to be measured, the probe needle of the probe card is pressed against the object to be measured with a predetermined force to apply needle pressure, and the electrodes of the probe needle and the object to be measured are Good electrical contact with the pad is maintained to obtain highly accurate measurement results. In this case, the stylus pressure of the probe needle is received by the highly rigid reinforcing body provided at the bottom of the board and the reinforcing ring provided on this reinforcing body, so the stylus pressure has very little effect on the board etc. The amount of deflection of the probe card due to needle pressure can be minimized, and poor contact between the probe needle and the object to be measured will not occur.

(Example) An example in which the present invention is applied to a wafer prober will be described with reference to the drawings.

Since the above-mentioned wafer prober is already well known, the entire explanation will be omitted and the main parts of the wafer probe will be explained first. In FIG. 1, a socket ring 11 is provided through a mounting ring on a ring insert 10 for mounting a probe card, a printed circuit board 12b is mounted on this socket ring 11, and this printed circuit board 12b and printed circuit board 12a are connected to each other.
are electrically connected by wiring 25. As shown in FIG. 2, a highly rigid metal reinforcing body (upper block) 13 made of aluminum or the like is fixed to the lower part of the printed circuit board 12a using fixing screws 13a or the like. here.

The reinforcing body 13 has a donut shape, and the reinforcing body 13 has a donut shape.
It has a reference surface facing 2b. A large number of probe needles 15 are positioned and fixed in the Z direction by an adhesive 14 such as an epoxy resin filled in the center of the reinforcing body 13 and a fixing plate 16. Furthermore, an intermediate block 17 is attached to the lower part of the reinforcing body 13. Lower block 18 and fixing screws 17a, 18a
are fixed through the middle block 17 and the lower block 1.
8 is provided with an upper guide plate 19 and a lower guide plate 2o to guide the probe needle 15 up and down so that it is positioned in XY. Further, the positioning pin 21 is connected to the reinforcing body 13.
, the intermediate block 17 and the lower block 18 to regulate the relative XY positions of each block.

The inner circumferential surface of a reinforcing ring 22 made of highly rigid aluminum or the like is fixed to the outer circumference of the lower surface of the above-mentioned fully conductive reinforcing body 13 via a fixing screw, and the outer circumferential surface of the reinforcing ring 22 is fixed to the outer circumference of the lower surface of the fully conductive reinforcing body 13.
It is fixed with a fixing screw to the bottom of the opening for attaching the probe card.

Next, the operation of the above embodiment will be explained.

As shown in FIG. 3(a), when measuring electrical characteristics by bringing the probe needles 15 into contact with the electrode pads of the semiconductor wafer 23, which is the object to be measured, the chuck top 24 is raised and the wafer 23 is brought into contact with the probe needles. 15, and then, as shown in FIG.
When overdrive is applied with an upward stroke of 0 μm, the probe needle 15 between the fixed plate 16 and the guide plate 19.20
A force in the longitudinal direction is applied to the needle 15 and the needle 15 is buckled and deformed. Therefore, the probe needle 15 is pressed against the semiconductor wafer 23 with a predetermined force and pressure is applied to the probe needle 15.
It is possible to maintain good electrical contact between the electrode pads of the wafer 23 and the electrode pads of the wafer 23, and obtain highly accurate measurement results. In this case, since the stylus pressure of the probe needle 15 is received by the highly rigid reinforcing body 13 provided at the bottom of the substrate 12a and the reinforcing ring 22 provided on this reinforcing body 13, the stylus pressure does not affect the substrate 12a etc. Since the amount of force applied is extremely small, the amount of deflection of the probe card due to needle pressure can be minimized, and poor contact between the probe needle 15 and the object to be measured will not occur.

In this example, if the semiconductor wafer 23 is raised with an upward stroke of 70 μm and an overdrive is applied to the probe needle 15, the printed circuit board with the conventional structure is
Although a deflection amount of about 0 μI11 to 45 μm occurs, according to this example, since the printed circuit board 12 receives stylus pressure by the highly rigid reinforcing body 13 and the reinforcing ring 22 provided on this reinforcing body 13, the printed circuit board 12 is deflected by about 5 μm. It only receives the amount of deflection,
It has been confirmed that the amount of deflection of the printed circuit board 12 can be minimized.

Since the stylus pressure of the probe needle is received by a highly rigid reinforcing body provided at the bottom of the board and a reinforcing ring provided on this reinforcing body, the stylus pressure has very little effect on the board etc., and the stylus pressure is Since the amount of deflection of the probe card can be minimized, the probe needle and the object to be measured can reliably come into contact and extremely accurate measurement results can be obtained.As is clear from the above, According to the present invention, there are the following excellent effects.

Conventionally, poor contact between the probe needle and the measuring end could not be detected, and the IC
However, the probe device of the present invention has improved the IC yield from 60% to 90%.

[Brief explanation of drawings]

The drawings show an embodiment of the probe device according to the present invention, and FIG. 1 is a partial cross-sectional view showing the mounting position of the vertical nail type probe card of the probe device, and FIG. 2 is a partially enlarged cross-sectional view of the same. , FIGS. 3(a) and 3(b) are explanatory cross-sectional views showing a state in which the probe needle of the above is overdriven, and FIG. 4 is a cross-sectional view showing a conventional probe card. 10 ・ ・ 12a, 13 ・ ・ 15 ・ ・ 22 ・ ・ 23 ・ ・ Phosphorus gain insert 12b...Printed circuit board, reinforcing body, probe needle, reinforcing ring, semiconductor wafer Patent Applicant: Tokyo Electron Ltd. No. Figure (α) (wa) Figure

Claims (2)

[Claims] (1) A probe device for measuring electrical characteristics by bringing a probe needle into contact with an object to be measured, characterized in that the pressure exerted by the probe needle is received by a rigid member. (2) The structure of the above-mentioned rigid member is such that a highly rigid metal reinforcing body is provided at the lower part of the substrate and this reinforcing body is provided in a part of the device main body via a highly rigid reinforcing ring. The probe device described.