JPH0833414B2 - Probing card - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a probing card used for a semiconductor wafer prober.

(Prior Art) Due to high integration of the IC, the number of terminals forming the IC increases, that is, the number of electrode pads per chip increases. There is also a corresponding demand for wafer prober technology for inspecting ICs with this increased number of electrode pads. For example, it is necessary to develop a device with an increased number of probe terminals on a probing card. As a means for increasing the number of probe terminals of a probing card, there has been proposed one in which the probe terminals are mounted substantially perpendicular to the device under test. For example, JP-A-60-18
9949, JP-A-61-154137, JP-A-61-205870, etc. propose a probe in which a probe terminal is vertically fixed to a substrate wired so as to be electrically conductive.
-11741, 57-5755, 58-148935,
In JP 59-12615, JP 62-36139, etc.,
It has been proposed to connect a substrate and a probe terminal that are electrically connected to each other via an elastic body such as a conductive spring.

(Problems to be solved by the invention) However, in the case where the probe terminal is vertically fixed to the substrate described above, the probe terminal is further overdriven when the probe terminal and the DUT are brought into contact with each other during the inspection. There is a problem that the probe terminal becomes brittle and lacks in durability due to damage such as distortion to the probe. Further, as a measure against this problem, there is one in which the substrate and the probe terminal are connected via an elastic body such as a conductive spring. However, the conductivity of a conductive spring is poor,
In addition, there is a problem in that pipes are required to hold the positions of the probe terminals and the springs, etc., and the components become minute parts, which makes installation difficult.

The present invention has been made to solve the above-mentioned problems. The probe terminals can be set to have a constant protruding length and can be mounted at a fine pitch. Moreover, the conductivity is good, and all probe terminals are always constant. It is an object of the present invention to provide a highly reliable probing card that can be brought into contact with an object to be inspected by the contact pressure.

[Structure of Invention]

(Means for Solving the Problems) The probing card of the present invention has a probe connected to a predetermined wiring of a printed circuit board at one end and a probe led out through a through hole provided in the printed circuit board at the free end side. In a plurality of probing cards, the through hole on the probe free end side is structured to serve as a guide for each probe, and a space between the guide and one end of the probe is covered with at least a surface insulating pipe to form an arc. In addition, as a means for setting the position of the probe on the free end side, a stopper is provided at a predetermined position of the probe.

Further, in the present invention, it is preferable that the probe is provided with a spring so as to surround the probe in a through hole that guides the free end side of the probe.

Further, in the present invention, it is preferable that the surface insulating pipe also serves as the stopper.

[Action effect]

According to this invention, the through-hole on the free end side of each probe has a structure that serves as a guide for each probe, and a space between the guide and one end of the probe is covered with at least a surface insulating pipe to form an arc shape. By simply inserting the free end of the probe into the through hole, each probe can be accurately attached to the predetermined position and mounted at a fine pitch, and the stopper can be used to set the position of the free end of the probe to the predetermined position of the probe. Since it is provided as a setting means, when the free end of the probe is inserted into the through hole, the stopper acts and the protruding length of the probe from the through hole can be automatically set to a constant length. Further, since the guide and the one end of the probe are covered with the insulating pipe, the insulation between the adjacent probes can be maintained. Further, even if the inspection of the inspection object is repeated, the protruding length of the probe from the through hole can be kept constant by the stopper, the conductivity is good, and the reliability can be improved.

Further, in the present invention, since the probe is provided with the spring so as to surround the probe in the through hole that guides the free end side of the probe, when the probe elastically contacts the inspected object, the pressing force applied to the probe is mainly applied to the spring. The probe can make electrical contact with the object to be inspected without applying excessive force to the probe, and improves the durability without damaging the probe such as distortion. be able to.

Further, in the present invention, if the surface insulating pipe also serves as the stopper, it is not necessary to newly provide a stopper separately from the surface insulating pipe.

(Example) Next, an example of the probing card of the present invention will be described with reference to the drawings.

As shown in FIG. 2, the probing card (1) is composed of a substrate portion (2) and a probe terminal installation portion (3).

The board portion (2) is a so-called printed board. As shown in FIG. 1, an insulating board (4) made of an insulating synthetic resin is electrically insulated with a predetermined pattern in an insulating state. The printed wiring (5) is electrically conductive. Each of the printed wirings (5) is configured so that one end thereof is connected to a terminal which is connected to a tester which is an inspection device for the object to be inspected and the other end is connected to a probe terminal (6). Here, when connecting the probe terminal (6) and the printed wiring (5), a circular through hole (7) having a diameter of, for example, 90 μm is provided so that one end of the probe terminal (6) can be inserted into the insulating substrate (4). Has been. The printed wiring (5) is provided up to the through hole (7), and one end of the probe terminal (6) is inserted into the through hole (7) and attached, for example, soldered in the through hole (7). Thus, the probe terminal (6) and the printed wiring (5) are connected and wired.

The probe terminal (6) is a material such as a tungsten wire (8) having an elastically deformable outer diameter of, for example, 80 μm. The position where the tungsten wire (8) contacts the inspected object, that is, the tip (9) has a diameter of, for example, 150 μm.
The conical contact part is made of a highly durable material such as beryllium copper. The tip (9) is formed into a conical shape by a known etching technique or the like at a position where it comes into contact with the object to be inspected. Further, an elastic body such as a coil spring (10) is provided so as to surround the tungsten wire (8) with a length of 1500 to 2000 μm in the longitudinal direction from the position of the tip (9). This coil spring (10)
Has an inner diameter smaller than the tip (9) of the probe terminal (6), the tip (9) of the probe terminal (6) serves as a stopper, and the coil spring (10) is elastically mounted so as not to come off. ) To give elasticity. Also, the tungsten wire (8) is spaced from the coil spring (10) by a predetermined length in the longitudinal direction, for example, about 600 to 1500 μm, and the tungsten wire (8) has, for example, an outer diameter of 160 μm and an inner diameter of 90 μm.
It is inserted into a SUS pipe (11) and is bonded, for example, thermocompression-bonded and fixed at this position. The pipe (11) is provided up to a position where it is inserted into the through hole (7) provided in the insulating substrate (4). In addition, this pipe (11) has an insulating member such as Teflon (trade name) on its surface to have a thickness of, for example, 10 to 20 μm so that the pipes (11) do not become conductive even if they come into contact with each other.
It is coated about m.

The probe terminal (6) as described above is installed from the substrate part (2) to the probe terminal installation part (3).
A probe terminal installation portion (3) is arranged on the substrate portion (2). In this probe terminal device section (3), a through hole is provided in the substrate section (2), and a circular insulating guide block (12) made of, for example, ceramics is formed in this hole.
The thickness is, for example, 2100 to 3500 μm. At a predetermined position of this guide block (12), guide holes (13a) (1
3b) are provided in large numbers as shown in FIG. The probe terminal (6) having the above-described configuration is inserted into the guide holes (13a) and (13b), and the guide hole (13a) is provided at a position where the tungsten wire (8) is surrounded by the coil spring (10). Has a diameter of, for example, about 150 to 160 μm, and at a position composed of only the tungsten wire (8) from the coil spring (10) to the position where the pipe (11) whose surface is covered with an insulating member is provided. The guide hole (13b) has a diameter of 90 μm, for example. That is, when the surface of the guide block (12) facing the object to be inspected is the lower surface (14), the guide hole (13a) of the guide block (12) has a length of, for example, 1500 to 2000 μm from the lower surface (14).
Has a diameter of, for example, 150 to 160 μm, and the length from this position to the upper surface (15) coaxially, for example, 600 to 1500 μm, is divided into two stages with a guide hole (13b) having a diameter of, for example, 90 μm. A large number of such guide holes (13a) (13b) are provided corresponding to the positions where the array pattern of the electrode pads (17) of the IC chip formed on the inspection object, for example, the semiconductor wafer (16) is formed. Even if the pitch interval of the guide holes (13a) is set to about 20 μm, it is possible to deal with it. Here, the installation state of the probe terminal (6) in the probing card (1) will be described.

The tip (9) of the probe terminal (6), which is the contact portion with the object to be inspected, is led out from the guide block (12) by, for example, 300 μm. In the portion of the tungsten wire (8) in which the coil spring (10) is surrounded by the tip (9), it is inserted into the guide hole (13a), and the guide having a small diameter is located only at the tungsten wire (8). Hole (13
inserted in b). Where the coil spring (1
The outer diameter of the coil spring (10) is the guide hole (13).
Since it is larger than the inner diameter of b), the guide hole (13b) serves as a stopper for the coil spring (10). The other end of the tungsten wire (8) has a through hole (7) in the insulating substrate (4).
Inserted in and soldered. From the upper surface of the through hole (7) to the upper surface (15) of the guide block (12), the tungsten wire (8) portion to which the pipe (11) is attached is provided in a curved state. When the probe terminal (6) is installed with the above configuration, a force in the extension direction is applied to the coil spring (10), so that the guide hole (13b)
Due to the stopper action, the tip end (9) of the probe terminal (6) is pushed down by the coil spring (10) toward the object to be inspected. Here, when the tip (9) is pushed down to a predetermined height position, the outer diameter of the pipe (11) fixed to the tungsten wire (8) is larger than the diameter of the guide hole (13b). ) It becomes a gas topper, and the tip (9) is accurately installed at a predetermined height position.

By configuring the probing card (1) as described above, the probe terminals (6) are vertically laid vertically with respect to the surface of the object to be inspected, for example, the semiconductor wafer (16), and the tips of the probe terminals (6) ( 9) are aligned on the planes orthogonal to each other.

Next, the above-mentioned probing card (1) is placed in a probe device (not shown), and the operation and action in the inspection of the inspection object will be described.

First, an object to be inspected, for example, a semiconductor wafer (16) is installed at a position facing the installation of the probing card (1). here,
The wafer (1) and the probing card (1) are moved relative to each other in the up-and-down direction. For example, the wafer (16) is lifted and the tip (9) of each probe terminal (6) of the probing card (1) and the wafer (16). A) contact the electrode pad (17). Here, the wafer (16) is further raised, that is, overdrive is applied, for example, 60 to 100 μm. By this overdrive, the oxide film and the like adhered to the electrode pad (17) of the wafer (16) is destroyed at the tip (9) of the probe terminal (6), and the tip (9) of the probe terminal (6) and the electrode pad. Correctly connect with the conductive member of (17). At this time, the probe terminal (6) is pushed upward as shown in FIG. 4, the pipe (11) and the guide block (12) are not in contact with each other, and the tungsten wire ( The curved portion of 7) is elastically deformed. Further, the coil spring (10) is sandwiched between the tip (9) and the guide hole (13b) and contracted as the tip (9) of the probe terminal (6) rises. In such a connection state, the test signal output from the tester (not shown) is applied to the input electrode (17) of the IC chip from the probe terminal (6), and the electric power generated in the output electrode (17) of the IC chip is generated. The target signal is output from the other probe terminal (6) to the tester, and compared with the signal expected by the tester to judge the quality of the IC chip and the function level.
After completion of this inspection, the wafer (16) is lowered by a predetermined amount.
As a result, the probe terminal (6) and the electrode pad (17)
Is in a non-contact state. At this time, the probe terminal (6)
Due to the elastic action of the coil spring, the tip (9) of the probe terminal (6) is pushed down, whereby the pipe (11) comes into contact with the guide block (12) and the pushing operation is stopped, and the probe terminal (6) is stopped. The tip (9) is installed at a predetermined height position.

As described above, the probe terminal is slidable in the vertical direction, and the height position of the probe terminal has reproducibility, so that the height position of the probe terminal is always set at an accurate height, and reliability of the probe terminal is improved. It is possible to improve.

The present invention is not limited to the above embodiment. For example, as shown in FIG. 5, the probe terminal (6) and the printed wiring (5) may be connected by soldering (18) one end of the probe terminal (6) directly to the printed wiring (5) portion.
Further, the material of the probe terminal may be any elastically deformable conductive material, the tip portion may be the same member, and the tip shape is not limited. Further, it is not limited to the coil spring, and any material may be used as long as it can give an elastic force to the probe terminal, and the material may be either conductive or insulating. Furthermore, any material may be used as long as it can deform the pipe. Furthermore, the material of the guide block may be any as long as it is insulating and durable,
The front and back surfaces may be seen through by using a thermosetting transparent resin. In this case, as a means for quickly visually setting the inspection object and the probe terminal installation portion (3) at the same position, a cross point is formed on the surface of the guide block (12) as a display portion corresponding to a predetermined portion of the inspection object. (14a)
It is also possible to align the positions of the object to be inspected by providing such marks and seeing through them. Also, as shown in FIG.
A through hole (19) may be provided at the center position of the guide block so that the other surface side can be viewed. Furthermore, the arrangement of the probe terminals may be such that the electrode pads of a plurality of IC chips can be inspected simultaneously, and the probe terminals are arranged so as to correspond to the arrangement of all the electrode pads of the IC chips formed on the wafer. Is also good. With such a configuration, it is possible to inspect one wafer at a time and the throughput is improved. Furthermore, the object to be inspected may be an LCD or the like instead of the semiconductor wafer. Furthermore, as shown in FIG. 5, instead of the pipe, a ceramic stopper (20) may be provided to adjust the height position of the probe terminal.

[Brief description of drawings]

FIG. 1 is an enlarged view of a main part of a probing card for explaining an embodiment of the present invention, FIG. 2 is a side view of the probing card of FIG. 1, and FIG. 3 is a top view of the probing card of FIG. FIG. 4 is a diagram for explaining the operation of the probing card of FIG. 1, and FIGS. 5 and 6 are diagrams for explaining another embodiment of FIG. 1 ... Probing card, 6 ... Probe terminal 8 ... Tungsten wire, 9 ... Tip 10 ... Coil spring, 11 ... Pipe 12 ... Guide block, 13a, b ... Guide hole

Claims (3)

[Claims] 1. A probing card provided with a plurality of probes, one end of which is connected to a predetermined wiring of a printed circuit board and whose free end side is led out through a through hole provided on the printed circuit board. The through hole on the end side has a structure that serves as a guide for each probe, and a space between this guide and one end of the probe is covered with at least a surface insulating pipe to form an arc, and the position of the probe on the free end side. A probing card characterized in that a stopper is provided at a predetermined position of the probe as a means for setting. 2. The probing card according to claim 1, wherein the probe is provided with a spring so as to surround and bend the probe in a through hole that guides the free end side of the probe. 3. The probing card according to claim 1 or 2, wherein the surface-insulated pipe also serves as the stopper.