KR100386648B1 - Probe card including vertical type needle with a buffering means - Google Patents

Abstract

A probe card comprising a vertical probe provided with a shock absorber is disclosed. The probe card according to the present invention comprises: (1) a printed circuit board for a probe card, (2) a ceramic substrate under the printed circuit board, (3) a vertical probe fixed to the ceramic substrate, and ④ a probe mounted under the ceramic substrate. A probe buffer board having a second hole for providing a buffering action, ⑤ a probe positioning board installed under the probe buffer board, ⑥ an alignment for coupling and aligning the printed circuit board, ceramic board, probe buffer board and probe positioning board And a ceramic support plate attached to the bottom surface of the printed circuit board to support the vertical probe top. The second hole formed in the probe buffer board causes the vertical probe to be bent sideways at regular intervals when the vertical probe is connected to the pad of the semiconductor chip, thereby causing the vertical probes to contact the pad of the semiconductor chip with a constant force, thereby damaging the pad. Suppresses and prolongs the life of the probe.

Description

Probe card including vertical type needle with a buffering means}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrical inspection apparatus for semiconductor devices, and more particularly, to a probe card used to electrically inspect a semiconductor chip in a wafer state.

In general, a semiconductor chip manufactured in a wafer state is a liquid crystal display (LCD) or an electrical die sorting (EDS) that inspects electrical characteristics before being assembled into a semiconductor package. Inspection).

As a result of the EDS inspection, the semiconductor chips of good products are assembled into a liquid crystal display device (LCD) or a semiconductor package, and the defective semiconductor chips are discarded without being assembled. This EDS test is a prober station equipped with a tester in which various measuring devices are built into a computer, and a probe card for electrically contacting a unit semiconductor chip of a wafer under test. Is performed using

The probe card is used as an intermediate medium for connecting a pad and a tester of the semiconductor chip to inspect the micro pattern of the semiconductor chip on the wafer and the characteristics of the electrode during the manufacturing process of the semiconductor device. Each needle on the probe card is in direct contact with the pad of the semiconductor chip. Therefore, the characteristics of the electrical function of the semiconductor chip are examined in good and defective form. Such probe cards are currently being used for EDS inspection of liquid crystal display devices (LCDs) and plasma display panels (PDPs) as well as semiconductor devices.

1 is a cross-sectional view of a probe card including a vertical probe according to the prior art.

Referring to FIG. 1, a cross-sectional view of a probe card shown in Korean Patent Publication No. 97-13150 (Title: Probe Card with Vertical Needle and Manufacturing Method thereof, Publication Date 1997-3.29), and a printed circuit board 1 , A plurality of vertical probes 5 contacting the pads of a semiconductor chip (not shown) are formed on a substrate composed of the auxiliary substrate 3 and the bonding means 4. In the drawing, reference numeral 2 denotes a circuit pattern formed on the printed circuit board 1, reference numeral 6 denotes a wire connecting the vertical probe 5 and the circuit pattern 2, and reference numeral 7 It refers to a protective cover that serves to protect the wire 6 from external impact.

However, the above-described probe card according to the related art has the following problems.

First, the vertical probe 5 does not have a large pressing force on the semiconductor chip individually, but when the pads of the probe and the semiconductor chip are in contact with each other, the vertical probe 5 presses the semiconductor chip with a high load. However, the vertical probe 5 and the printed circuit board 1 and the auxiliary substrate 3 do not have means for buffering these loads. Thus, the high load is concentrated on one or two vertical probes which protrude specifically in case the flatness of the vertical probe 5 is uneven. If such a high load is concentrated on a specific vertical probe, damage due to high load may occur when the probe contacts the pad of the semiconductor chip in the EDS inspection process.

Second, since the vertical probe cannot perform a buffering function on its own, fatigue characteristics are easily degraded during the repeated EDS test, and the vertical probe is broken or flatness, which causes the probe card to fail.

The technical problem to be achieved by the present invention is to prevent the damage to the pads of the semiconductor chip that can be caused by the vertical probe during the EDS inspection, by installing a means for performing a buffer action in the vertical probe, the vertical probe To provide a probe card that can extend the service life of the probe and improve the electrical conductivity of the vertical probe.

1 is a cross-sectional view of a probe card including a vertical probe according to the prior art.

2 is a cross-sectional view of a probe card including a vertical probe provided with a buffer means according to the first embodiment of the present invention.

3 is an enlarged cross-sectional view of a portion A of FIG. 2.

4 is an enlarged cross-sectional view of a portion B of FIG. 2.

FIG. 5 is a plan view of the printed circuit board for the probe card in FIG. 2.

FIG. 6 is a plan view when the pattern expansion ceramic substrate is installed on the printed circuit board of FIG. 5.

7 is a plan view of a ceramic substrate.

FIG. 8 is a partial cross-sectional view of a portion excluding the printed circuit board of FIG. 2.

FIG. 9 is a cross-sectional view of the vertical probe of FIG. 8 when it is in contact with a pad of a semiconductor chip.

10 is a cross-sectional view of a probe card including a vertical probe provided with a buffer means according to a second embodiment of the present invention.

FIG. 11 is a partial cross-sectional view of a portion excluding the printed circuit board of FIG. 10.

FIG. 12 is a cross-sectional view illustrating a shape when the vertical probe contacts the pad of the semiconductor chip in FIG. 10.

Explanation of symbols on the main parts of the drawings

100: printed circuit board, 102: ceramic substrate,

104: vertical probe, 106: probe buffer board,

108: probe positioning board, 110: alignment bar,

112: ceramic support plate, 114: alignment bar cover,

116: bonding means, 118: projections,

120: circuit pattern, 122: circuit pattern contact,

124: probe fixing part, 126: soldering part.

In order to achieve the above technical problem, the present invention comprises a plurality of ① printed circuit board for the probe card, and (2) parallel to the lower portion of the printed circuit board, the expansion circuit pattern, the contact connecting projection and the probe is fitted therein A pattern expansion ceramic substrate including first holes and electrically connected to the printed circuit board through the protrusions; and a vertical probe fixed to the ceramic substrate by being vertically inserted into the ceramic substrate under the printed circuit board. A probe buffer substrate configured to be parallel to the lower portion of the ceramic substrate, the second probe having a clearance therein for moving the vertical probe fixed to the ceramic substrate in one direction, and ⑤ configured to be parallel to the lower portion of the probe buffer substrate; The vertical probe passing through the second hole of the probe buffer board may be connected to the semiconductor chip in a fixed state. A probe positioning board including a third hole for aligning, ⑥ an alignment rod formed perpendicular to the printed circuit board, a ceramic board, a probe buffer board, and a probe positioning board, and coupling and aligning them with each other, ⑦ the printed circuit board Providing a probe card, characterized in that having a ceramic support plate attached to the back of the contact with the top of the vertical probe fixed to the ceramic substrate.

According to a preferred embodiment of the present invention, it is preferable that the second hole of the probe buffer substrate has a larger diameter than the first and third holes of the ceramic substrate and the probe positioning substrate, and the probe buffer substrate is at least one. Suitable. In addition, in the case where the probe buffer substrate is more than one, it is preferable that the clearance in which the probe moves in one direction in the second hole is formed to cross in both directions about the probe, so that the probe is designed to be bent in an 'S' shape. .

Preferably, the circuit pattern and the protrusion of the ceramic substrate are suitably made of gold (Au), and the height of the protrusion of the pattern expansion ceramic substrate is suitably in the range of 100-1000 μm.

In addition, according to a preferred embodiment of the present invention, the alignment rod is made of a ceramic film, it is suitable to use an adhesive means when combining the printed circuit board, ceramic substrate, probe buffer substrate and probe positioning substrate, Ceramic epoxy (Caramic Epoxy) may be used as the bonding means.

In addition, the vertical probe is preferably in the range of 10 ~ 70 ㎛ diameter, the end of the straight line is not tapered, the vertical probe is preferably protruded in the range of 100-800 ㎛ outside the probe positioning substrate.

According to the present invention, the pad damage of the semiconductor chip can be suppressed because the vertical probe and the pad of the semiconductor chip are contacted using the buffer means installed on the probe card, and the buffer means can extend the life of the vertical probe. Can be. Also, it is easy to apply to EDS inspection of semiconductor chip with fine pitch pad, and because the length of vertical probe is the same, it can secure uniform conductivity in EDS inspection process for semiconductor chip, ceramic substrate and printing Since the circuit boards are bonded without using soldering, the life of the printed circuit board can be semi-permanently extended.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The basic member constituting the probe card used in the present specification is used in the widest sense and is not limited only to the specific shape and material described in the drawings below. The invention can be practiced in other ways without departing from its spirit and essential features. For example, in the following preferred embodiment, the ceramic substrate, the probe buffer substrate, and the probe positioning substrate are ceramic, but this may be a material such as sapphire or glass. Alternatively, the protrusion material of the ceramic substrate may be replaced with platinum (Pt) or silver (Ag), which is another material having excellent conductivity instead of gold (Au). In addition, although the number of the probe buffer boards is illustrated in this embodiment to two, it is also possible to increase to two or more as necessary. Therefore, the content described in the following preferred embodiments is exemplary and not intended to be limiting.

First embodiment: A probe card using two probe buffer substrates.

2 is a cross-sectional view of a probe card including a vertical probe provided with a buffer means according to the first embodiment of the present invention.

Referring to Figure 2, the configuration of the probe card according to the first embodiment of the present invention is ① is configured in parallel with the printed circuit board 100 for the probe card, ② the lower portion of the printed circuit board 100 for the expansion therein 3 includes a circuit pattern (120 of FIG. 3), a contact connecting protrusion 118 and a plurality of first holes into which the probe is inserted, and is electrically connected to the printed circuit board 100 through the protrusion 118. A pattern expansion ceramic substrate 102, a vertical probe 104 inserted into the ceramic substrate 102 vertically under the printed circuit board 100, soldered and fixed, and a lower portion of the ceramic substrate 102. Probe buffer substrates 106A and 106B formed in parallel with the second hole and having a clearance therein, wherein a vertical probe fixed to the ceramic substrate 102 can move in one direction, and ⑤ the probe buffer substrate 106A. 106B) is constructed parallel to the lower part and A probe positioning board 108 including a third hole for allowing the vertical probe 104 to pass through the second hole of the probe buffer board to be connected to the semiconductor chip in a fixed state; and ⑥ the printed circuit board 100. ), The alignment bar 110 formed perpendicular to the ceramic substrate 102, the probe buffer substrate 106 and the probe positioning substrate 108, and coupling and aligning them with each other, ⑦ the back of the printed circuit board 100 And a ceramic support plate 112 attached to the upper surface of the vertical probe 104 fixed to the ceramic substrate 102.

When the alignment rod 110 combines the printed circuit board 100, the ceramic substrate 102, the probe buffer substrate 106, and the probe position adjusting substrate 108, an adhesive means 116 such as a ceramic epoxy is bonded. To use. One end of the alignment rod 100 is capped by the alignment rod cover 114 while protruding from the printed circuit board. The ceramic substrate 102, the probe buffer substrate 106 and the probe positioning substrate 108 are formed using ceramic, which is suitable for improving the temperature characteristics of the probe card.

3 is an enlarged cross-sectional view of a portion A of FIG. 2. In detail, the printed circuit board 100 and the pattern expansion ceramic substrate 102 are enlarged to show that they are coupled to each other. In the past, their coupling was connected to each other using a permanent coupling means such as soldering. In the present invention, the protrusions 118 having a height of 100-1000 μm on the ceramic substrate 102 and the circuit pattern contacts 122 formed on the general printed circuit board 100 are aligned with each other without being fixed.

The circuit pattern contact 122 of the printed circuit board 100 has a cylindrical shape of about 50-70 μm in height, but if necessary, it may be formed slightly higher. Therefore, since the circuit pattern 120 and the protrusion 118 in the ceramic substrate 102 are soft metals such as pure gold Au, the protrusion 118 is inserted into the grooves of the circuit pattern contact 122. It is meant to be combined. Therefore, there is an advantage in that the semi-permanent life can be increased by not soldering the printed circuit board 100.

4 is an enlarged cross-sectional view of a portion B of FIG. 2. In detail, it is a view for explaining the length of the vertical probe 104 protruding below the probe positioning substrate 108 and the degree to which the vertical probe 104 protrudes below the probe positioning substrate 108. L1) is 100-800 占 퐉 so that the tip is stably in contact with the pad of the semiconductor chip while the middle portion of the vertical probe 104 is bent during EDS inspection.

FIG. 5 is a plan view of the printed circuit board for the probe card in FIG. 2.

Referring to FIG. 5, the shape of the printed circuit board 100 may generally use the printed circuit board 100 used for the probe card. And it can be seen that the circuit pattern contact 122 is formed in the center connected to the protrusion of the ceramic substrate 102. A ceramic support plate 112 is attached to the center of the circuit pattern contact 122 formed in two rows to press the upper portion of the vertical probe 104.

FIG. 6 is a plan view when a pattern expansion ceramic substrate is installed on the printed circuit board of FIG. 5, and FIG. 7 is a plan view of the ceramic substrate.

6 and 7, the pattern expansion ceramic substrate 102 includes both protrusions 118 formed of pure gold Au, arranged in a plurality of rows, and the protrusions are made of pure gold Au. It is connected to the pattern 120 and extends to the first hole, that is, the probe fixing part 124. That is, the vertical probe is inserted into the probe fixing part 124, which is the first hole, and fixed by soldering. The pattern expansion ceramic substrate 102 is fixed using the printed circuit board 100, the alignment bar 110, and the bonding means (116 of FIG. 2) while the vertical probe is fixed.

In addition, after the vertical probe 104 is inserted into the probe fixing part 124, soldering is performed, and a vertical type is applied by applying a conductive paste in a dotting manner and then curing. The probe 104 may be fixed to the probe fixing part 124 of the ceramic substrate 102.

FIG. 8 is a partial cross-sectional view of a portion excluding the printed circuit board of FIG. 2, and FIG. 9 is a cross-sectional view of a shape when the probe contacts the pad of the semiconductor chip of FIG. 8.

8 and 9, the probe 104 used in the probe card according to the present invention maintains a straight shape when the EDS test is not performed, but when pressed with a high load in connection with the pad of the semiconductor chip. The gap C in the second hole of the probe buffer substrates 106A and 106B is bent in an 'S' shape.

In the drawing, reference numeral 112 denotes a ceramic support plate, 126 denotes a soldering portion for fixing the vertical probe 104, 102 denotes a ceramic substrate for pattern expansion, and 108 denotes a probe positioning substrate.

Therefore, in the case of EDS inspection of a semiconductor chip having hundreds or more pads in one semiconductor chip such as a microprocessor or an application specific integrated circuit (ASIC), hundreds or more vertical probes are required. At high loads, the vertical probe 104 and the pad (not shown) of the semiconductor chip come into contact with each other. In this case, when there is no clearance between the vertical probe 104, that is, the probe buffer substrates 106A and B as in the present invention, the pad of the semiconductor chip is damaged as in the above-described problems of the related art. Was induced.

However, in the present invention, the vertical probe 104 is properly bent at the moment when the vertical probe 104 is in contact with the pad of the semiconductor chip, so that even if a slight flatness error occurs in a large number of vertical probes 104, a high load to be pressed is applied. It is designed to be distributed, not concentrated in one place. Therefore, damage caused when the vertical probe is pressed against the pad of the semiconductor chip at a high load can be suppressed. The buffer means for bringing the above-described vertical probe 104 into contact with the pad of the semiconductor chip while being bent at the time of EDS inspection is a main means for achieving the object of the present invention.

In addition, the clearance C is formed so as to intersect in both directions about the vertical probe 104, so that the F is applied to the vertical probe 104 itself due to the proper bend in the 'S' shape during the EDS inspection. There is an advantage that can be reduced to extend the life of the probe. The width of the clearance C may be appropriately set in consideration of the number of probe buffer substrates used, the number of vertical probes, and the like.

The vertical probe 104 is preferably manufactured to have a straight shape having an outer diameter of 10-70 μm from tungsten, but this may be modified in other forms in the art.

Second Embodiment A probe card using one probe buffer substrate.

FIG. 10 is a cross-sectional view of a probe card including a vertical probe provided with one probe buffer board according to a second embodiment of the present invention. FIG. 11 is a partial cross-sectional view of a portion excluding the printed circuit board of FIG. 10. 10 is a cross-sectional view showing a shape when the vertical probe is in contact with the pad of the semiconductor chip.

10 to 12, all of the differences compared to the first embodiment described above have the same configuration and operation principle except for using one probe buffer substrate 206 instead of two. . Reference numerals are also configured to correspond with each other in the above-described first embodiment for better understanding. Therefore, detailed description will be omitted to avoid duplication.

The present invention is not limited to the above embodiments, and it is apparent that many modifications can be made by those skilled in the art within the technical spirit to which the present invention belongs.

Thus, according to the present invention described above, first, since a vertical probe can be bent through the play of the second hole in the probe buffer board, even if the vertical probe is in contact with the pad of the semiconductor chip at a high load, any specific probe It is possible to prevent the pad damage of the semiconductor chip caused by the force concentrated on the.

Second, because the vertical probe can bend through the play of the second hole formed in the probe buffer board during the EDS test, the fatigue characteristic applied to the probe can be improved to extend the life of the vertical probe. have.

Third, since the probe card is made using a vertical straight probe in the range of 10 to 70 μm, it can be applied to the EDS inspection of semiconductor chips having fine pitch type pads. In particular, if the pad is a wafer having a lead on chip (LOC) type semiconductor chip formed at the center of the semiconductor chip, it is possible to manufacture a probe card capable of simultaneously inspecting one wafer at a time as long as it supports the tester's ability. .

Fourth, since the lengths of the vertical probes are the same, the influence of noise can be minimized during the EDS inspection of the semiconductor chip, and a uniform conductivity for the vertical probe can be secured.

Fifth, the ceramic substrate, the probe buffer substrate, the probe positioning substrate, and the alignment rod used in the present invention are made of a ceramic material having a small dimensional deformation with respect to heat and hardly occurring deformation. For this reason, even if the EDS inspection is performed in a high temperature environment, it is possible to suppress the misalignment between the vertical probe and the pad of the semiconductor chip due to deformation or dimensional change of the probe card.

Sixth, in the present invention, in order to electrically connect the pattern expansion ceramic substrate and the probe card printed circuit board, the solder is not used to connect the protrusion of the pattern expansion ceramic substrate and the circuit pattern contact of the printed circuit board without soldering. . Because of this, it is possible to directly use the printed circuit board once used on another probe card and to use it semi-permanently without damaging the printed circuit board.

Claims (10)

Printed circuit boards for probe cards; A pattern extending in parallel with the lower portion of the printed circuit board and including a plurality of first holes into which an expansion circuit pattern, a contact connection protrusion, and a probe are fitted, and which are electrically connected to the printed circuit board through the protrusion Ceramic substrates; A vertical probe fixed to the ceramic substrate by being inserted into the ceramic substrate under the printed circuit board; A probe buffer substrate configured to be parallel to the lower portion of the ceramic substrate, and having a second hole formed therein, wherein the vertical probe fixed to the ceramic substrate includes a play capable of moving in one direction; A probe positioning substrate configured to be parallel to the bottom of the probe buffer board and including a third hole to allow the vertical probe passing through the second hole of the probe buffer board to be connected to the semiconductor chip in a fixed state; An alignment rod which is formed perpendicular to the printed circuit board, the ceramic substrate, the probe buffer board, and the probe positioning board, and couples and aligns them with each other; And And a ceramic support plate attached to a rear surface of the printed circuit board and in contact with an upper end of a vertical probe fixed to the ceramic board. The method of claim 1, And a second hole of the probe buffer substrate has a larger diameter than the first and third holes of the ceramic substrate and the probe positioning substrate. The method of claim 1, And at least one probe buffer substrate. The method of claim 1, Probe card, characterized in that the circuit pattern and the protrusion of the ceramic substrate is made of gold (Au). The method of claim 1, Probe card, characterized in that the height of the projection of the pattern expansion ceramic substrate is in the range of 100-1000㎛. The method of claim 1, The alignment rod is made of a ceramic film, the probe card, characterized in that the bonding means is used to combine the printed circuit board, ceramic substrate, probe buffer board and probe positioning substrate. The method of claim 6, The bonding means is a probe card, characterized in that the ceramic (Caramic Epoxy). The method of claim 1, The vertical probe is a probe card, characterized in that the diameter ranges from 10 to 70㎛, the end is not a straight line. The method of claim 1, And the vertical probe protrudes out of the probe positioning substrate in the range of 100-800 μm. The method of claim 3, In the case where the probe buffer substrate is one or more, the probe that can move in one direction in the second hole is formed so as to cross in both directions around the probe, the probe card characterized in that the probe is designed to be bent in the 'S' shape .