JPS5826529Y2 - Fixed probe board - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a fixed probe board used for inspection and measurement of semiconductor devices completed on a semiconductor wafer.

BACKGROUND OF THE INVENTION Conventionally, in the extremely wide variety of semiconductor manufacturing processes such as monolithic semiconductor integrated circuits, the blobbing process has tended to exist as an intermediate inspection.

However, when the entire process is roughly divided into the process up to the masked wafer and the process up to the finished product, the blobbing process is a final check process that is comparable to a sea urchin fly, and it has a significant impact on labor saving and rationalization in the subsequent process. Rather than being large, it is a very important position.

In other words, as it has become possible to significantly reduce the defectiveness rate in the post-processes leading to the finished product through automation, etc., the accuracy of checking in the blobbing process has a significant impact on product yield. It is from.

A fixed probe board is used in this blobbing process, for example, November 5, 1970.
P14 of electronic materials [November special issue] published by Tani
No. 5, "Use of fixed probe card" and the method disclosed in Japanese Patent Publication No. 54-43354 are known.

As shown in the "Electronic Materials" section above, this fixed probe board is useful because it solves the drawback of poor workability for mass-produced products such as needle alignment and maintenance in adjustable multi-point probers. It is shown.

The details of the main parts of the structure are shown in Figure 1.
It is disclosed in Japanese Patent Publication No. 54-43354.

As shown in the figure, this fixed probe board (test probe assembly) has a support (base member) 3 that fixes and supports the probe needle 5 at the intermediate part around the opening of the printed circuit board 1 at a specific angle. It is fixed to the supporting surface by a fixing layer 4.

The reason for this is not clearly stated, but when fixing the probe needle 3 with an adhesive that hardens through work over time or by heating, by providing the above angle, the probe needle 5 can be reliably embedded in the fixing layer 4. It is presumed that this is intended to enhance the effect of fixing the probe needle 5 to the support surface.

However, when the probe needle 5 is supported by the fixing layer 4, electrical connection is obtained by pressing the tip 6 of the probe needle 5 against the bonding pad (electrode) of the wafer chip completed on the wafer. Therefore, all the stress when the probe needle 5 is crimped is applied to the inside of the fixed layer 4.

Since there are variations in the springiness of the tip of each probe needle and variations in the hardness of the fixing layer 4 with respect to the probe needle, the support of the probe needle 5 in the fixing layer 4 is reduced by repeated pressure bonding to mass-produced products. The points change, resulting in variations in the direction perpendicular to the contact surface at the tip 6 of the probe needle.

If vertical variations occur in the tip 6 of the probe needle in this manner, not only insufficient contact occurs when pressing the probe needle tip 6 onto the wafer chip, but also variations in the needle pressure against the wafer chip.

Here, since wafer chips have a piezo effect in which the crystal structure changes due to uneven pressure and changes the semiconductor element characteristics, the above-mentioned variation in stylus pressure has a negative effect on the wafer chips and also It has been found that there is a problem in that the reliability of test results cannot be maintained.

This idea was made in order to provide a probe board that secures the fixing effect of the probe needle and prevents the dispersion of the position due to repeated crimping of the tip of the probe needle.

This idea uses a hard support having a support surface that contacts and supports the intermediate support part of the probe needle, and also provides a groove on the support surface and/or the side surface near the support surface, and supports the probe needle including the groove. The purpose is to provide a fixing layer on the surface of the body that embeds the intermediate support portion of the probe needle.

This invention will be described in detail below along with examples.

Broadly speaking, the probe board according to this embodiment is as follows:
a printed circuit board having a circular opening in the center; radiation wiring that extends radially from a predetermined position around the opening, to which probe needles are selectively connected, and which alternately serve as first and second radiation parts; A printed wiring that extends from the first radiating section to the insertion side of the printed circuit board is connected to the second radiating section via a through hole, and is formed on the back side of the printed circuit board extending from the through hole to the insertion side. As shown in FIG. 2, as a mounting means for the probe needle, a support 3 having a support surface and grooves 3 a and 3 b that contact and support the probe needle is used as a probe board having a printed wiring. , and a fixing layer 4 are used.

That is, in the same figure, 1 is a printed circuit board,
An opening 2 is provided in its center.

Then, on the upper surface (back surface), a printed wiring connected to the second radiating section 10a via the through hole 10 is formed, and on the lower surface (front surface), the printed wiring (not shown) is formed to connect to the first radiating section 10a. ) is formed.

The second radiation part 10a constitutes one of the connection ends provided at a predetermined position around the circular opening 2, and connects one end 7 of the probe needle 5 with solder 8. be.

Similarly, a large number of probe needles are connected to corresponding connection ends (first radiating section or second radiating section).

The support 3 that supports the probe needle around the opening 2 is
Each of the probe needles is fixed to the lower surface of the printed circuit board 1 in a conical radial shape at a specific angle, and its support surface is tapered to match the angle and comes into contact with each probe needle. It is formed like this.

As shown in the enlarged cross-sectional view of FIG. 3, the supporting surface is provided with a groove having a wedge-shaped cross section.

Furthermore, a groove 3b is formed on the side surface near the support surface.

The fixing layer 4 is embedded in the surface (including the side surface) of the support 3 including the grooves 3 a and 3 b so as to embed the supporting portion of the probe needle 5 with the probe needle 5 in contact with the support surface. It is intended to provide

This fixing layer 4 fixes the probe needle 5 to the support surface of the support body 3 with an adhesive that hardens during processing over time or by heating, and due to its fluidity during processing,
It can be easily formed by being injected into the grooves 3a and 3b.

Therefore, the groove 3a provided on the support surface allows the periphery of the support portion of the probe needle 5 to be reliably filled with the fixation layer, so that the fixation effect is maintained.

In particular, in this embodiment, since the cross-sectional shape of the groove 3a is wedge-shaped, the effect can be further enhanced.

Furthermore, in this embodiment, a groove 3b is also provided on the side surface near the support surface, and by integrally forming the fixing layer 4 over this side surface portion, the probe needle 5
The fixing effect can be further enhanced.

Since the stress during crimping of the probe needle tip 6 is applied to the hard support 3, the surface of the support does not deform due to repeated crimping, and the stress is applied in a direction perpendicular to the contact surface of the probe needle tip. variation can be prevented.

Note that during this crimping, a tensile force is applied to the outer part of the probe needle 5 with respect to the outer part of the fixing layer 4 using the inner part of the support as a fulcrum. The groove 3b and the wedge-shaped groove 3a on the surface allow it to be firmly held.

In addition, the force applied to the tip of the probe needle is not only applied during the above-mentioned crimping, but also applies to the tip of the probe needle.
When adjusting and readjusting the position of the probe needle, forces are applied in various directions, so by using the support and fixation layer with the above structure, it is possible to reliably hold the probe needle against these forces. It can be fixed.

Therefore, the positioning of the tip 6 during readjustment can be performed with high precision, and a defective probe needle can be pulled out and
Even when reattaching it, highly accurate positioning is possible by attaching it in contact with the support surface of the support body.

In this embodiment, the connecting portion between the support body 3 and the Pnont substrate 1 is provided with a mating portion 9 as shown in FIG.
Instead of providing a clearance 9', a play 9' is provided.

The reason for this is that in order to easily align the tip 6 of the probe needle to the bonding pad, the probe needle 5 and the support 3 are first fixed together using a positioning jig, and then the support 3 is When connecting to the Phnom board 1, the probe needle 5
This is to facilitate alignment between one end 7, which is the connecting portion of the connector, and the corresponding connecting end 10a of the printed circuit board 1, etc.

In other words, when a large number of probe needles (several ten probe needles) are fixed to the support 3, the positioning of the tip portions 6 needs to be performed with high accuracy by inserting them into masked holes etc. provided corresponding to the bonding pads. However, this is not done accurately for the connecting end 7, and it is desirable to simplify the alignment on the connecting end 7 side in order to reduce the number of man-hours and simplify the jig.

In this case, as shown in FIG. 1, if the mating portion 9 has no play, the support 3 to which a large number of probe needles are fixed is fixed to the printed circuit board 1, and the connecting end 10 of the printed wiring is fixed to the printed circuit board 1. Although it becomes difficult to align the one end 7 of the probe needle with respect to the printed wiring when soldering the probe needle a, by providing a gap 9' as in this embodiment, the one end 7 of the probe needle This makes it easy to correct positional variations in.

In other words, the positioning of the connection end side of the probe needle can be made more roughly, so that the number of assembly steps can be simplified.

This invention is not limited to the above embodiments, and the grooves provided in the support body 3 may be the grooves 3a provided on the support surface or the grooves 3a provided on the side surface.
It may be only b.

Further, the support 3 may be made of a hard metal and may have an insulating film formed on its surface.

Furthermore, the shape of the opening provided in the printed circuit board 1 and the overall shape of the support body 3 can be variously modified as necessary.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of the prior art, FIG. 2 is a sectional view showing an embodiment of the invention, and FIG. 3 is an enlarged view of the main parts thereof. 1...Printed circuit board, 2...Opening, 3
...Support, 3a, 3b...Groove, 4.
...Fixed layer, 5...Probe needle, 6...
...Tip, 7...Connection part, 8...
Solder, 9...Mating part, 9'...Gap, 10...Through hole, 11...Ink container, 12... Capillary, 13...
ink.

Claims (1)

[Scope of utility model registration request] 1. A printed circuit board having an opening in the center and a plurality of wiring means having connecting ends at predetermined positions on the lower surface side corresponding to the periphery of the opening, one end being connected to the connecting end, and the other end being connected to the connecting end. A plurality of probe needles are arranged in a substantially conical radial shape pointing linearly toward the center below the opening, and the tips of the probe needles are aligned so as to face the electrodes of the semiconductor chip to be measured; A support surface is provided on the lower surface around the opening and provides planar support in contact with the intermediate portion of the probe needle, and a groove is provided on a part of this support surface and/or a side surface near the support surface, and a hard and an insulating fixing layer provided on the support surface including the groove of the support so as to bury the intermediate portion of the probe needle. Features a fixed probe board. 2. The fixed probe board according to claim 1, wherein the cross-sectional shape of the groove is wedge-shaped.