JP4778164B2 - Contact and probe card - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a contactor and a probe card used for an energization test of a plurality of chip regions formed on a semiconductor wafer, and more particularly to an energization test of a plurality of chip regions each having a plurality of electrodes at locations corresponding to each side of a rectangle. The present invention relates to a contactor suitable for use and a probe card.
[0002]
[Prior art]
In a semiconductor wafer, a plurality of chip regions, each of which is a semiconductor device, that is, an IC chip, are generally formed in a matrix. Each chip region has a rectangular shape, and has a plurality of electrode pads, that is, pad electrodes on each of a plurality of edges corresponding to each side of the rectangle. The chip regions forming each row and each column of the matrix are usually aligned in a straight line.
[0003]
This type of chip area is subjected to an energization test to determine whether the circuit operates as specified. Such an energization test is often performed in a state before the chip region is separated from the wafer, and is also performed using a probe card having a plurality of contacts whose tips are pressed against pad electrodes in the chip region. .
[0004]
It is desired that the contact used in this type of energization test has a certain degree of elasticity so that a predetermined pressing force is applied to the pad electrode in the chip region by the overdrive at the tip. As such a contact, a needle type probe having a tapered tip, a film type probe element having a protruding electrode at the tip, and the like, which are mounted on an assembly substrate in a cantilever shape have been proposed.
[0005]
[Problems to be solved]
However, in the conventional contact, even though the chip area of the semiconductor wafer itself is small, the area of each contact from the place where it is attached to the substrate to the place where the pad electrode is pressed (area where elastic deformation occurs due to overdrive) Therefore, it is difficult to manufacture a probe card that can simultaneously conduct energization tests on four adjacent chip regions via a virtual boundary line (scribe line) that intersects in a cross shape.
[0006]
An object of the present invention is to apply a predetermined pressing force to the electrode in the chip region without increasing the length of the contact.
[0007]
[Solution, action, effect]
The contact according to the present invention is a bending member that has a base end portion and a tip end portion and is folded at least once between the base end portion and the tip end portion, and a mounting portion that is attached to the assembly board. A mounting portion disposed at the base end portion, and a projecting electrode that is in contact with the electrode of the semiconductor wafer and disposed at the distal end portion.
[0008]
The contact is mounted on the assembly substrate at the mounting portion, and the protruding electrode is pressed against the electrode in the chip region. In the contact, since the bent member is folded at least once, the length of the contact is short even if the pressing force to the electrode in the tip region and the amount of displacement with respect to the electrode are the same as the conventional one. Become.
[0009]
However, when the protruding electrode is pressed against the electrode in the tip region, the bending member is elastically deformed at least at the portion having the mounting portion and the portion bent from this portion, whereby the protruding electrode is inserted into the tip. A predetermined amount is displaced with respect to the electrode in the region, and a rubbing action is applied to the electrode in the tip region, and a predetermined pressing force is applied to the electrode.
[0010]
The bending members are a pair of first portions having the base end portions where the mounting portions are arranged, respectively, extend in the same direction at intervals in a horizontal plane, and are integrally joined on the distal end side. The pair of first parts and the tip where the protruding electrode is disposed as a second part extending from the joint part of the first part toward the mounting portion between the first parts A second portion having a portion. By doing so, when the protruding electrode is pressed against the electrode in the chip region, the bending member is elastically deformed at the first and second portions.
[0011]
However, each of the bent members is a pair of first portions having the base end portions on which the mounting portions are disposed, and extends in the same direction at intervals in a horizontal plane and integrally joined at the distal end side. A pair of the first parts, a second part extending from the coupling part of the first part toward the mounting portion between the first parts, and a tip side of the second part A third part that is folded downward from the second part and extends the lower side of the second part toward the coupling part, and is folded downward from the coupling part side of the third part to the lower side. And a fourth portion that extends from the lower side of the third portion toward the opposite side of the coupling portion and has the tip portion on which the protruding electrode is disposed. By doing so, since the bending member is elastically deformed at the four portions, the length dimension of the contact can be further shortened.
[0012]
The bending member includes a first portion having the base end portion on which the mounting portion is disposed, the first portion extending in a horizontal plane, and a lower side from a distal end side of the first portion. A second portion that is folded back and extends from the lower side of the first portion toward the mounting portion and having the tip portion on which the protruding electrode is disposed. Good. By doing so, since the width dimension of the contact may be small, the mechanical strength of the contact can be increased.
[0013]
The protruding electrode may have a conical shape. By doing so, an effective rubbing action can be given to the electrode in the chip region.
[0014]
The positions of the mounting portion and the protruding electrode in the longitudinal direction of the first and second portions can be made the same. By doing so, the length dimension of the contact can be effectively shortened.
[0015]
The probe card according to the present invention is used for an energization test of a plurality of chip regions formed on a semiconductor wafer, each having a plurality of electrodes at locations corresponding to the sides of the rectangle. Such a probe card includes a plurality of contacts having the above-described structure, and an assembly board having a plurality of wiring lands on the lower surface. Each contact is mounted on the wiring land at the mounting portion so that the protruding electrode faces downward.
[0016]
Also in the probe card according to the present invention, since the contact member having the mounting portion at one end of the bent member that is folded at least once and having the protruding electrode at the other end portion is used, the length dimension of the contact member is determined. The amount of displacement of the pressed portion with respect to the electrode in the chip region can be increased without increasing the size.
[0017]
In the probe card according to the present invention, the contacts are divided into groups corresponding to the sides of the rectangle and spaced in the direction of the corresponding sides, and among the contacts of each group, in the arrangement direction thereof. At least one contact located at one end extends from the position corresponding to the electrode of the chip region to which the mounting portion and the protruding electrode correspond to the arrangement direction of the corresponding group of contacts, and the remaining plurality of contacts are the mounting The portion and the protruding electrode can extend from the side corresponding to the state of the corresponding side to the side corresponding to the side. By doing so, even if the electrode is formed even at the end of the side of the chip region, a plurality of contacts corresponding to the electrode of the chip region can be effectively arranged.
[0018]
The probe card according to the present invention further includes a wiring board on which the assembly board is mounted on a lower surface, and the wiring board includes a plurality of wirings individually corresponding to the wiring lands, and the wirings electrically individually. A plurality of connection lands connected to the connection lands, and a plurality of spring members individually attached to the connection lands, and the assembly board is further individually associated with the connection lands. A plurality of through holes penetrating in the thickness direction are provided, and the wiring and the wiring land are connection pins arranged in the through holes and electrically connected by connection pins pressed against the spring member. Can be. If it does so, since the connection pin is pressed by the spring member and the connection land when the wiring board and the assembly board are assembled in a mutually pressed state, the wiring of the wiring board and the wiring land of the assembly board Are securely connected.
[0019]
The spring member may include one or more bases attached to the connection land and a plate-like spring part disposed on the base in a state of being spaced downward from the connection land. . By doing so, since the connection pin is pressed against the spring member and the connection land, the wiring on the wiring board and the wiring land on the assembly board are securely connected.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the contact 10 includes a bending member 12 that is folded back once between a base end portion and a tip end portion, and a pair of mounting portions 14 that are disposed at the base end portion of the bending member 12. , And the protruding electrode 16 disposed at the tip of the bending member 12. As will be described later, the protruding electrode 16 is pressed against the pad electrode 18 in the chip region.
[0021]
The bending member 12 includes a pair of first portions 20 that extend from the proximal end portion toward the distal end side at an interval in the same plane and are integrally joined on the distal end side, and the coupling of the first portion 20 The second part 22 that is folded back from the part in the same plane as the first part 20 and extends further between the first parts 20 toward the proximal end side of the first part 20 is formed into a plane E shape. Is formed. The mounting portion 14, the first and second portions 20 and 22, and the connecting portions of both the portions 20 and 22 all have a rectangular cross-sectional shape and are integrally formed.
[0022]
Each mounting portion 14 is formed so as to protrude upward at the base end portion of the first portion 20, and acts as a portion to be mounted on an assembly board described later. The protruding electrode 16 is formed in a state of protruding downward at the tip of the second portion 22 and acts as a location electrically connected to the pad electrode 18 of the semiconductor wafer.
[0023]
When the protruding electrode 16 of the contactor 10 is pressed against the pad electrode 18, the bending member 12 is elastically deformed at both the first portions 20 and the first portion 20 from the coupling portion of both the first portions 20. The second portion 22 extending in the opposite direction is also elastically deformed.
[0024]
Accordingly, the contact 10 is displaced by a predetermined amount with respect to the pad electrode 18 in a state where the tip of the protruding electrode 16 is in contact with the pad electrode 18, and a rubbing action caused by the displacement of the protruding electrode 16 acts on the pad electrode 18. . The contact 10 applies a predetermined pressing force to the pad electrode 18 by elastic deformation due to overdrive.
[0025]
However, since the second portion 22 is folded back with respect to the first portions 20, the length of the contact 10 is shortened even if the pressing force to the pad electrode 18 is the same as the conventional one.
[0026]
Therefore, according to the contact 10, a predetermined pressing force is applied to the pad electrode 18 even though the length dimension is small. Therefore, the probe card using such a contact 10 can effectively arrange the wiring lands, as will be described later, with a wide wiring land arrangement area of the assembly board on which the contacts are assembled. .
[0027]
In the illustrated example, the protruding electrode 16 has a pyramid shape, but may have another shape such as a conical shape or a hemispherical shape. However, when a sharp protruding electrode such as a pyramid or conical shape is used, the sharp tip of the protruding electrode is displaced with respect to the pad electrode 18 in a state of being bitten into the electrode, so that an effective rubbing action is given to the electrode. be able to.
[0028]
In the illustrated example, the mounting portion 14 and the protruding electrode 16 are disposed at the same position in the longitudinal direction of the first and second portions 20 and 22. Thereby, the length dimension of the contactor 10 can be shortened effectively. However, the mounting portion 14 and the protruding electrode 16 may be disposed at different positions in the longitudinal direction of the first and second portions 20 and 22.
[0029]
The contact 10 can be manufactured by using a photolithographic technique and an electroforming technique. One example will be described below.
[0030]
First, a metal base plate having a recess corresponding to the protruding electrode on one surface is prepared.
[0031]
Next, a first photoresist layer is formed on one surface of the base plate, and this first photoresist layer is exposed and developed, so that the protruding electrodes 16 of the contactor 10, both the first portions 20 and the first photoresist layer are exposed. A recess corresponding to the second portion 22 is formed in the first photoresist layer, and the recess is filled with a conductive metal by electroforming.
[0032]
Next, a second photoresist layer is formed on one side of the base, and this second photoresist layer is exposed and developed, so that the recess corresponding to the mounting portion 14 of the contact 10 is the second. Formed in the photoresist layer, this recess is filled with conductive metal by electroforming.
[0033]
Next, all the photoresist is removed, and then the metal member or contact remaining on the base plate is removed from the base plate. Thereby, the contact 10 is manufactured.
[0034]
Referring to FIG. 2, the contact 30 includes a bent member 32 that is bent back and forth between one end and the other end, and a pair of mounting portions 14 that are disposed at one end of the bent member 32. And the protruding electrode 16 disposed at the other end of the bending member 32.
[0035]
In addition to the first and second portions 20 and 22, the bending member 32 is further folded downward from the distal end side of the second portion 22 so that the lower side of the second portion 22 is the second portion. A third portion 34 that extends further toward the base end side of the second portion 22, and a lower portion of the third portion 34 that is folded downward from the distal end side of the third portion 34. And a fourth portion 36 further extending toward the end side.
[0036]
Also in the contactor 30, the mounting portion 14, the first, second, third, and fourth portions 20, 22, 34, 36 and the connecting portions of the adjacent portions 20, 22, 34, 36 are all rectangular. These cross-sectional shapes are formed integrally with each other. Further, the mounting portion 14 and the protruding electrode 16 are arranged at the same position in the longitudinal direction of the first, second, third and fourth portions 20, 22, 34 and 36.
[0037]
In the contactor 30, each mounting portion 14 is disposed at the proximal end portion of the first member 20, but the protruding electrode 16 is disposed at the distal end portion of the fourth portion 36. Similarly to the contact 10, the contact 30 can also be manufactured by using a photolithographic technique and an electroforming technique.
[0038]
In the contact 30, when the protruding electrode 16 is pressed against the pad electrode 18 of the semiconductor wafer, the bending member 32 has four first, second, third and fourth portions 20, 22, 34 and 36. It is elastically deformed at the location and is displaced by a predetermined amount with respect to the pad electrode 18 in a state where the tip of the protruding electrode 16 is in contact with the pad electrode 18.
[0039]
As a result, the contact 30 causes a predetermined pressing force to act on the pad electrode 18 and causes a predetermined rubbing action to act on the pad electrode 18. Further, since the contact 30 is elastically deformed at the four portions, the length of the contact 30 can be further shortened.
[0040]
Next, an embodiment of the probe card 40 using the contact 10 shown in FIG. 1 will be described with reference to FIGS.
[0041]
As shown in FIG. 11, the probe card 40 is used for an energization test of a plurality of chip regions 44 having a rectangular shape formed in a matrix on a semiconductor wafer 42. Each chip region 44 has a plurality of pad electrodes 18 on each side of the rectangle spaced apart in the longitudinal direction of the side. Adjacent chip regions 44 are cut at a virtual boundary line 46.
[0042]
In the figure, the probe card 40, as can be performed at the same electrical test of the four chip regions 44 adjacent to each other via a borderline 46 that intersect in a cross shape is shown, the present invention is 2 ⁿ The present invention can also be applied to a probe card that can be simultaneously performed in the energization test of the chip region 44.
[0043]
The probe card 40 includes a wiring board 50, an assembly board 52 assembled on the lower surface of the wiring board 50, and a plurality of contacts 10 mounted on the assembly board 52.
[0044]
The wiring board 50 has a plurality of tester lands 54 electrically connected to the tester on the outer peripheral edge portion of the upper surface and a plurality of conductive connection lands 56 on the lower surface, and is connected to the tester land 54. The lands 56 are electrically connected to the lands 56 in a one-to-one manner by wirings 58.
[0045]
Each wiring 58 includes a first wiring portion extending in parallel with the wiring substrate 50 and a second wiring portion extending from one end of the first wiring portion to the lower side of the wiring substrate 50 and electrically connected to the land 56. And have. The wiring board 50 can be formed of an electrically insulating material such as glass-filled epoxy in a state where the wirings 58 are multilayered.
[0046]
Each connection land 56 is assembled with a spring member 60 having conductivity. As shown in FIGS. 6 and 7, the spring member 60 integrally has a plate-like spring portion 64 on the lower surface of a pair of base portions 62 spaced in a direction parallel to the lower surface of the wiring board 50. In addition, a conductive adhesive such as solder is attached to the lower surface of the corresponding connection land 56 on the upper surface of the base 62.
[0047]
The lower surface of the assembly substrate 52 is divided into a plurality of contact regions 66 each having a rectangular shape corresponding to the chip region 44. Each contactor area 66 is divided by a virtual boundary line 68 as in the chip area 44. Each boundary line (scribe line) 68 acts as a side of the contact region 66.
[0048]
A plurality of wiring lands 70 are formed in each contact area 66. Each wiring land 70 corresponds to the pad electrode 18 in the chip region 44, and extends from the portion corresponding to the pad electrode 18 to the center side of the contact region 66. As shown in FIG. 8, each wiring land 70 can be a part of a wiring pattern having a circular land portion 70 at one end.
[0049]
The assembly substrate 52 also has a plurality of through holes 74 that penetrate the assembly substrate 52 in the thickness direction, and a plurality of recesses 76 that open to the upper surface of the assembly substrate 52. The lower end of each through hole 74 is closed by the land portion 70 of the wiring land 70. Each recess 76 communicates with the through hole 74 and receives the connection land 56 and the spring member 60.
[0050]
A conductive connection pin 78 is disposed in each through hole 74. The connection pin 78 has a length that is slightly longer than the length from the lower surface of the assembly substrate 52 to the spring member 60. Both ends of the connection pin 78 are formed in a hemispherical shape.
[0051]
In each contact 10, the protruding electrode 16 extends downward toward the corresponding pad electrode 18, and the first portion 20 extends from the side 68 corresponding to the contact region 66 toward the center of the chip region 66. In an extended state, the mounting portion 14 can be attached to the other end portion of the wiring land 70 of the assembly substrate 52 with a conductive adhesive such as solder.
[0052]
The assembly substrate 52 can be formed of a heat-resistant and electrically insulating material such as ceramics. The assembly substrate 52 is assembled to the wiring substrate 50 by the plurality of screw members 80 shown in FIG. 3 with the connection pins 78 disposed in the through holes 74.
[0053]
In the state where the assembly board 52 is assembled as described above, each connection pin 78 is sandwiched between the spring member 60 and the wiring land 70 and slightly elastically deformed. Thereby, the connection pin 70 pushes both in the opposite direction, and each spring member 60 is slightly elastically deformed at the spring portion 64. For this reason, the connection pin 70 is electrically and reliably connected to both the spring member 60 and the wiring land 70, and the contact 10 is electrically connected to the tester land 54.
[0054]
The contacts 10 are divided into groups individually corresponding to the sides of the contact region 66, and are arranged at intervals in the direction of the corresponding sides. Among the contacts 10 of each group, the contact 10 located at one end in the arrangement direction corresponds to the pad electrode 18 to which the arrangement direction mounting portion 14 and the protruding electrode 16 correspond as shown in FIGS. 9 and 10. The remaining contactors 10 face the corresponding sides 68 from the locations corresponding to the pad electrodes 18 corresponding to the mounting portions 14 and the protruding electrodes 16. It extends toward side 68.
[0055]
The probe card 40 uses the contact 10 which is folded back between the base end portion where the mounting portion 14 is formed and the distal end portion where the protruding electrode 16 is formed to have a short length. Although the dimensions are small, a predetermined rubbing action is applied to the pad electrode 18.
[0056]
Further, the probe card 40 has a smaller proportion of the contact area 10 to the contact area 66, and the wide central area of the contact area 66 can be used effectively for the wiring land 70.
[0057]
Furthermore, the probe card 40 is arranged in a state in which the contact 10 located at one end in the arrangement direction of the contact 10 of each group extends in parallel with the corresponding side 68 of the contact region 66. Even if the pad electrode 18 is formed up to the end of each side 68, the plurality of contacts 10 corresponding to the pad electrode 18 in the chip region 66 can be effectively arranged.
[0058]
A probe card using the contact 30 shown in FIG. 2 can be formed and used in the same manner as the probe card 40.
[0059]
The present invention can be applied not only to the contacts 10 and 30 having the shape shown in FIGS. 1 and 2, but also to contacts having other shapes and a probe card using the same. For example, in the contact 30 shown in FIG. 2, the first and second portions 20 and 22 are removed, and the mounting portion 14 is formed at the joint portion 38 between the second portion 22 and the third portion 34. It is good also as a contact of a shape.
[0060]
The present invention can be applied not only to a current test for a semiconductor wafer or chip region having a pad electrode, but also to a current test for a semiconductor wafer or chip region having another electrode.
[0061]
The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a contact according to the present invention.
FIG. 2 is a perspective view showing another embodiment of the contact according to the present invention.
FIG. 3 is a bottom view showing an embodiment of a probe card according to the present invention.
4 is a view of the probe card shown in FIG. 3 as viewed from below in FIG. 3;
5 is an enlarged cross-sectional view of a part of the probe card shown in FIG.
FIG. 6 is a cross-sectional view showing an embodiment of a state of electrical connection between the wiring of the wiring board and the wiring land of the assembly board.
FIG. 7 is a perspective view showing an embodiment of an electrical connection state between a connection pin and a spring member.
FIG. 8 is an enlarged view showing an example of an arrangement state of wiring lands on an assembly board.
FIG. 9 is a perspective view showing an example of an arrangement state of a plurality of contacts in one group.
FIG. 10 is a diagram illustrating an example of an arrangement state of a plurality of groups of contacts existing around a virtual boundary line;
FIG. 11 is a diagram showing an example of a chip region on a semiconductor wafer.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10, 30 Contact 12, 32 Folding member 14 Mounting part 16 Projection electrode 18 Electrode 20, 22, 34, 36 of bending area 40 Probe card 42 Semiconductor wafer 44 Chip area 46 Chip area boundary line 50 Wiring board 52 Assembly board 54 Tester land 56 Wiring board connection land 58 Wiring board wiring 60 Spring member 62 Spring member base 64 Spring member spring part 66 Contact area 68 Contact area boundary 70 Assembly land wiring land 74 Assembly substrate through hole 76 Assembly substrate recess 78 Connection pin

Claims (4)

A plurality of chip regions formed in a semiconductor wafer, and a probe card used for an energization test of a plurality of chip regions each having a plurality of pad electrodes at locations corresponding to each side of a rectangle,
An assembly board having a plurality of wiring lands on the lower surface;
A bending member having a base end portion and a tip end portion and folded back at least once between the base end portion and the tip end portion, and a mounting portion to be attached to the assembly board, which is disposed at the base end portion. A plurality of contacts each having a mounting portion and a protruding electrode that is in contact with an electrode of a semiconductor wafer and disposed at the tip portion, wherein the protruding electrode faces downward A plurality of contacts mounted on the land;
A wiring board mounted on the lower surface of the assembly board;
The wiring board includes a plurality of wirings individually corresponding to the wiring lands, a plurality of connection lands electrically connected to the wirings, and a plurality of wirings individually attached to the connection lands. With a spring member on the lower surface,
The assembly board includes a plurality of through holes that individually correspond to the connection lands and penetrate the assembly board in the thickness direction;
The probe card, wherein the wiring and the wiring land are electrically connected by a connection pin disposed in the through hole and pressed by the spring member.   2. The probe card according to claim 1, wherein the spring member includes one or more bases attached to the connection land and a spring part disposed on the base in a state of being spaced downward from the connection land.   The assembly board further includes a recess that opens upward and communicates with the through-hole, and that receives a pair of the connection land and the spring member on an upper surface side. Listed probe card. The contacts are divided into groups for each side of the rectangle and spaced in the direction of the corresponding side,
Among the contacts in each group, the contacts located at at least one end in the arrangement direction thereof are moved from the positions corresponding to the electrodes of the chip region corresponding to the mounting portion and the protruding electrodes to the arrangement direction of the corresponding group of contacts. Stretched,
4. The probe according to claim 3, wherein the remaining plurality of contacts extend from a side corresponding to a state in which the mounting portion and the protruding electrode are on a corresponding side to a side corresponding to the side. card.

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