JP2007218890A - Probe assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a probe assembly of which the vertical probes formed in resin films are formed into cantilever structure. <P>SOLUTION: A conductive part including the vertical probes 12 forms a parallelogram of a link 16 having a parallel spring 15, in this probe assembly of the present invention using the resin films adhered with a copper foil, formed with the conductive part including the vertical probe 12 on the each resin film by etching work of the copper foil, layered with the plurality of resin films with the vertical probe, and for bringing tip parts of the the vertical probes 12 collectively into contact with an electrode pad of a semiconductor chip to inspect a circuit of the semiconductor chip. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a probe assembly of a prober device used for circuit inspection of a plurality of semiconductor chips formed on a semiconductor wafer in a manufacturing process of an electronic device such as an LSI, and in particular, circuit terminals arranged on the semiconductor chip. The present invention relates to a probe assembly of a prober apparatus used for a probing test in which a vertical probe is brought into contact with a (pad) in a wafer state and the electrical continuity of semiconductor chips is collectively measured.

  With the advancement of semiconductor technology, the degree of integration of electronic devices has improved, and the area occupied by circuit wiring also increases in each semiconductor chip formed on a semiconductor wafer. Therefore, the circuit terminals (pads) on each semiconductor chip have increased. The number of pads has been increased, and the pad array has been miniaturized by reducing the pad area and the pad pitch. At the same time, a chip size package (CSP) system in which a semiconductor chip is mounted in a circuit board or the like as a bare chip without being housed in a package is becoming mainstream. For this purpose, in a wafer state before being divided into semiconductor chips, A characteristic check and pass / fail judgment are absolutely necessary.

  In particular, the problem with the miniaturization (narrow pitch) of the pad arrangement is to obtain electrical continuity by contacting the pads of the semiconductor chip during the electrical characteristics test and circuit inspection of the electronic device. This means that the structure of the probe must be adapted to the miniaturization of the pad array, and various measuring means are used to cope with the advancement of the miniaturization of the pad array.

  For example, there is a means for interposing a probe assembly in which a plurality of needle-like probes having an elastically deforming portion elastically deforming with respect to an external force are arranged between a pad of a semiconductor chip to be inspected and an inspection apparatus. A printed wiring board called a probe card is used as means for electrically connecting the probe assembly and the test circuit of the semiconductor chip.

  In general, in a probe card, when a needle-like probe having a cantilever structure of a cantilever is adopted, the tip portion of the probe that comes into contact with a pad of a semiconductor chip has a narrow pitch. However, the base part connected to the probe card can be roughened because the probe is arranged radially extending from the tip part, and the connecting means such as soldering the probe to the circuit terminal of the probe card It was possible to fix with. However, this cantilever structure has a problem that the tip is displaced in the horizontal direction when contacting the pad, so that the pad is scratched, or the measurement yield is lowered due to coming off the pad. Furthermore, there are problems that only one chip can be measured, there is a variation in the mounting accuracy of each probe, and it is difficult to control a constant contact pressure.

  In a vertical probe that replaces this cantilever structure, that is, a vertical probe in which the probe is fixed vertically to the circuit terminal of the probe card, the pad pitch on the semiconductor chip is equal to the circuit terminal pitch on the probe card. It is necessary to consist of. However, on the probe card which is a printed wiring board, there is a limit in manufacturing technology to make a circuit pattern finer, so it is difficult to satisfy the requirements for the area occupied by the circuit terminal and the wiring width according to the pad pitch. . Furthermore, since there is a limit to the pitch interval at which soldering is possible, it has been impossible to vertically fix the vertical probe to the probe card in accordance with the pad pitch of the semiconductor chip as miniaturization progresses.

  Thus, on the probe card, the proportion of the planar area occupied by the circuit wiring width in addition to the circuit terminal area is large, which hinders the narrowing of the pitch of the circuit terminals. Therefore, the number of vertical probes is maintained by using a multilayer printed wiring board for the probe card, arranging the circuit terminals in a grid pattern or in a two-row zigzag pattern, and electrically connecting the wiring between the layers through through holes. The means to do is also taken. However, since the space occupied by the through-holes becomes large, the presence of the through-holes also prevents the pitch of the circuit terminal array from being narrowed. As described above, when trying to fix the vertical probe to the probe card, in addition to the difficulty in narrowing the circuit terminals, it requires an advanced technique and a large number of man-hours for the soldering operation, which is expensive. It was. In order to solve these problems, the present inventors have proposed a vertical probe assembly and have already proposed a prober device using the vertical probe assembly (Patent Document 1 and Patent Document). 2).

  As shown in FIG. 22 of Patent Document 1 and FIG. 4 of Patent Document 2, a vertical probe assembly as a conventional example proposed by the present inventors has a copper thin plate on a ribbon-shaped (strip-shaped) resin film surface. By sticking and etching this copper thin plate, a vertical copper probe having a curved portion is formed on the surface of the resin film, and a plurality of resin films with the probe are laminated to constitute a vertical probe assembly. is there.

  Since this vertical probe assembly has a structure in which resin films are laminated, it is possible to place a plurality of probes in a very narrow area, and the resin film has openings so that the probes are vertical. The middle part of the probe is curved along the edge of the opening, and the structure is such that the strain caused by the pressure when the probe tip contacts the pad is absorbed by the opening of the resin film and the curved part of the probe. .

In this way, regarding how to release the pressure applied to the probe and the resin film during measurement, the inventors have proposed various shapes by devising the size and shape of the opening of the resin film and the curved shape of the probe. . However, even if it is possible to provide a probe assembly adapted to narrow pitch, if the processing of the resin film and the probe becomes complicated, the cost may increase. Accordingly, the present invention provides a vertical probe assembly in which the shape of a probe formed on a resin film is a simple structure close to a cantilever structure, and processing is easy including manufacturing steps such as forming an opening of a resin film. It is.
JP 2004-274010 A JP-A-2005-300545

  As described above, the prober apparatus using the film-stacked vertical probe assembly already proposed by the present inventors has been applied to a semiconductor chip having a narrowed pad pitch, for example, 45 μm pitch or less (for example, 20 μm pitch). It is a device that can also measure. Moreover, since automatic assembly is possible without using soldering or resin fixing means when assembling probes, low-cost mass production is possible, and all probes can be contacted vertically with respect to chip pads. On the other hand, a great advantage such as being able to control the contact pressure evenly is obtained.

  The present invention makes use of these advantages and makes the shape of the probe formed on the resin film a simple structure close to a cantilever structure, and facilitates processing including manufacturing steps such as forming the opening of the resin film. It provides a solid.

  The present invention uses a resin film to which a copper foil is bonded, etching the copper foil to form a conductive part including a vertical probe on the resin film, and laminating a plurality of resin films with the vertical probe to form a semiconductor. In a probe assembly for carrying out circuit inspection of a semiconductor chip by bringing the tip of a vertical probe into contact with the electrode pad of the chip at a time, the conductive part including the vertical probe forms a parallelogram link mechanism having a parallel spring structure It is characterized by that.

  Further, the present invention is a cantilever structure in which the parallelogram link mechanism having the parallel spring structure has the vertical probe on one end side and extends in the horizontal direction using the other end side as a support portion, and the parallel spring Is a link mechanism that is bent and deformed, and an opening is provided in the resin film between the parallel springs, or an opening is not provided.

  Further, the present invention is characterized by comprising a terminal portion that is connected to the vertical probe via a link mechanism and a conductive portion and that contacts a connection pad of a circuit board, and the terminal portion is a resin film with a probe Each of the resin films is formed such that the arrangement positions thereof are shifted at an equal pitch when the layers are stacked, and the conductive portion near the terminal portion is provided with a curved portion. In addition, the link mechanism and the terminal part are provided with a notch part in the vicinity thereof to form a cantilever structure, and when etching the copper foil, a part other than the conductive part is left without being removed to form a dummy member part. The resin film is a reinforcing member, and the resin film surface between the conductive portion and the dummy member portion is filled with an insulating adhesive.

  In the probe assembly of the present invention, the structure of the vertical probe in the resin film with the probe is a parallel spring structure, so that the movement distance in the horizontal direction is reduced compared to the movement of the tip of the cantilever needle, which has been a problem in the past. Can do. This means that a probe having a cantilever structure can be applied even if the pad area of the semiconductor chip is miniaturized. In addition, the conventional vertical probe needs to be made narrower as the pitch becomes narrower, and there is a limit to the elastic strength of the curved portion. However, in the present invention, a cantilever structure using a parallel spring is used without providing a curved portion. Can sufficiently cope with the elastic strength. Furthermore, since it is not necessary to have a complicated structure such as a curved portion, the copper foil can be easily etched, and the manufacturing cost can be reduced.

  Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1A, 1B, and 1C are principle diagrams for explaining the movement of the tip of the vertical probe. Note that the tip of the vertical probe remains vertical until it contacts a pad such as a semiconductor chip.

In FIG. 1 (a), the vertical probe 12 attached to the tip of a cantilever 11 having a length L has its tip facing perpendicularly to the upper surface of a pad 13 such as a semiconductor chip, and the other end is a support. 14 is in a horizontal state. Next, when the pad portion 13 is raised or the support portion 14 is lowered for inspection, the tip of the vertical probe 12 and the upper surface of the pad portion 13 come into contact with each other, and the cantilever 11 having the length L is calculated to be approximately (1/3). ) rotates around the position of the L, the distal end portion of the vertical probe 12 moves largely by the distance d ₀ in the longitudinal direction while being in contact with the upper surface of the pad portion 13. As a result, the distal end portion of the vertical probe 12 is detached from the pad portion 13, or the upper surface of the pad portion 13 is scraped or left scratched.

In order to eliminate this problem, the cantilever 11 has a link structure with a parallel spring 15 as shown in FIG. 1B, and a vertical probe 12 is provided at one end of the link 16. According to this link structure, FIG. 1 as the contact load of the same vertical direction is applied as (a), the movement amount d ₁ of the distal end portion of the vertical probe 12 for a link structure in a vertical probe 12,
d ₁ <d ₀
Therefore, it can be suppressed to a very small amount of movement.

FIG. 1C shows a link structure in which the shape of the parallel spring 15 constituting the cantilever is deformed in advance. In this case as well, the moving amount d ₂ of the tip of the vertical probe 12 is
d ₂ <d ₀
Therefore, it can be suppressed to a very small amount of movement.

  Next, a first embodiment of a resin film with a vertical probe (hereinafter simply referred to as a film with a probe) according to the present invention to which the principle described with reference to FIG. 1 is applied will be described with reference to the plan view of FIG. As shown in FIG. 2, the cantilever structure probe formed on the resin film surface uses a 20 μm thick beryllium copper thin plate, and this copper thin plate attached to a 5 μm thick polyimide resin film is etched. Form.

  This film with a probe is formed of a vertical probe 12, a parallel spring 15 that holds the vertical probe 12 on one end side, and a support portion 14 that supports the parallel spring 15 on the other end side. Slightly protrudes from the resin film (not shown). As shown in FIG. 2, for example, the parallel spring 15 has a single spring width a of 20 μm and an overall width b of the link 16 of 0.4 to 1 mm. As in this example, when the spring width is narrow, the resin film between the parallel springs 15 is not provided with an opening, so that the resin film itself has resistance to deformation, and only the copper thin plate is processed to be parallel. A structure in which the spring 15 is reinforced may be used.

  FIG. 3 is a plan view showing a second embodiment of the vertical probe. In this figure, 25 indicates a resin film. The resin film 25 has a ribbon shape that can accommodate the entire probe configuration except for the tip of the vertical probe 12. The parallel spring 15 has a vertical probe 12 on one end side and a support portion 14 on the other end side. The parallel spring 15 has a link structure inclined by an angle θ with respect to the horizontal direction. This is an example of the modified structure of FIG.

  Further, a terminal portion 17 that is in contact with the connection pad 19 of the circuit board 18 and serves as an electrical connection portion with the vertical probe 12 is formed on the support portion 14 via a curved portion 22. Moreover, when the resin film 25 with a probe is laminated, a hole 20 is provided through which a support rod that is a positioning and fixing portion of the resin film 25 is passed through the laminated resin film. A probe assembly is formed by laminating a plurality of resin films 25 each having the vertical probe. Furthermore, the feature of this embodiment is that instead of providing an opening in the portion corresponding to the opening of the resin film 25 between the parallel springs 15, copper foil is left as the dummy member 21, and the resin film 25 and the parallel spring 15 It plays the role of a reinforcing plate to increase the deformation resistance.

  Similarly, a parallel spring 24 is also provided in the support portion 14, and a dummy member 23 is provided between the parallel springs 24 in the support portion 14 portion to serve as a reinforcing plate. Further, since the parallel spring 24 is also provided on the support portion 14, the curved portion 22 and the terminal portion 16 are also elastically deformed and electrically connected when electrically connected to the connection pad 19 of the circuit board 18. Making it easy.

  FIG. 4 is a diagram illustrating a state in which the films with probes described in FIG. 3 are stacked. However, in FIG. 4, the resin film is not shown, and only the probe, the parallel spring, and the support portion are stacked. As can be seen from FIG. 4, the terminal portions 17 are formed on the respective resin films so that the phases of the terminal portions 17 are shifted in advance so that the phase of the terminal portions 17 serving as electrical connection portions is shifted at an equal pitch p when the films with probes are laminated. ing. In this case, when the connection pads 19 of the electrical connection portions of the circuit board 18 connected to the terminal portions 17 are provided, the connection pads 19 are matched with the connection pads 19 arranged in advance in an oblique direction so that the connection pads 19 are easily arranged.

  FIG. 5 is a plan view showing a third embodiment of the present invention. The feature of this embodiment is that an opening and a cut are provided in a portion where a parallel spring is formed on a resin film, and a cut is also provided in a portion where a terminal portion for electrical connection with a circuit board is provided. It is. As shown in the drawing, the copper foil attached to the resin film 25 is formed separately into a portion that becomes a conductive portion and an electrically dummy member that also serves as a reinforcing portion. A vertical probe 12 is formed on one end side of a portion that becomes a conductive portion, and a terminal portion 17 that contacts a connection pad 19 that is an electrical connection portion of the circuit board 18 is formed on the other end side. The reason why the dummy members 26 and 27 are provided is that the thickness of the copper foil is 20 μm while the thickness of the resin film 25 is as thin as 5 μm, so that the deformation strength as a film with a probe is maintained.

  Further, the vertical probe 12 is formed to be a link mechanism provided with a parallel spring 15, an opening 28 is provided in a resin film portion between the parallel springs 15, and a notch 29 is provided in parallel with the link mechanism. Thus, a cantilever structure including the vertical probe 12 is formed. Moreover, the notch 30 is provided along the terminal part 17, and the terminal part 17 also has the cantilever structure according to the notch length. Thus, since the probe portion has a cantilever structure with a parallel spring mechanism, the width of the conductive wiring 31 can be widened, so that the curved portion is provided in the middle of one vertical probe which is a conventional structure. Thus, the deformation strength of the resin film can be further increased. Further, since the terminal portion 17 has a cantilever structure, when the circuit board and the vertical probe are electrically connected, it is only necessary to connect them by elastic contact, so that the circuit board and the probe assembly can be easily attached. Can do.

  Further, an insulating adhesive 32 is poured into the gap between the conductive wiring 31 connecting the vertical probe 12 and the terminal portion 17 and the dummy members 26 and 27 to maintain electrical insulation and film strength, and serves as a reinforcing spacer. Yes. Furthermore, the resin film 25 in the vicinity of the vertical probe 12 is provided with a hole 20 through which a rod for positioning and fixing when the resin film 25 is laminated is formed. The function of passing this rod has already been described in the above-mentioned Patent Document 2 (Japanese Patent Application Laid-Open No. 2005-300545), and is omitted here. In FIG. 5, the lines indicated by reference numerals 35, 36 and 37 are meaningless lines for the explanation of the present invention and should be ignored.

  The resin film with a probe including the present proposal can be applied to a circuit inspection apparatus (prober) corresponding to a narrow pitch of a semiconductor device. For example, several tens to several hundreds of semiconductor chips with a diameter of 300 mm are formed. It has a function that can fully follow the batch inspection of wafers.

  It is explanatory drawing which shows the motion of the vertical probe which concerns on this invention.   It is a top view which shows 1st Embodiment of the vertical probe which concerns on this invention.   It is a top view which shows 2nd Embodiment of the vertical probe which concerns on this invention.   It is a perspective view explaining the probe assembly of this invention.   It is a top view which shows 3rd Embodiment of the vertical probe which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Cantilever 12 Vertical probe 13 Pad part 14 Support part 15 Parallel spring 16 Link 17 Terminal part 18 Circuit board 19 Connection pad 20 Hole 21 Dummy member 22 Bending part 23 Dummy member 24 Parallel spring 25 Resin film 26 Dummy member 27 Dummy member 28 Opening Part 29 Notch 30 Notch 31 Conductive wiring 32 Adhesive

Claims (11)

  Using a resin film to which a copper foil is bonded, etching the copper foil to form a conductive part including a vertical probe on the resin film, and laminating a plurality of resin films with the vertical probe to form an electrode of a semiconductor chip In a probe assembly for performing circuit inspection of a semiconductor chip by bringing the tip of the vertical probe into contact with a pad at once, a conductive part including the vertical probe forms a parallelogram link mechanism having a parallel spring structure. A probe assembly characterized by comprising:   2. The probe assembly according to claim 1, wherein the parallelogram link mechanism having the parallel spring structure has a cantilever structure having the vertical probe on one end side and extending in the horizontal direction with the other end side as a support portion. Solid.   2. The probe assembly according to claim 1, wherein the parallel spring is a link mechanism deformed by bending.   The probe assembly according to claim 1, wherein an opening is provided in the resin film between the parallel springs.   The probe assembly according to claim 1, wherein no opening is provided in the resin film between the parallel springs.   A probe assembly comprising a terminal portion that is connected to the vertical probe via a link mechanism and a conductive portion and that contacts a connection pad of a circuit board.   The probe assembly according to claim 6, wherein the terminal portion is formed on each resin film such that when the resin films with probes are laminated, the positions of the terminals are shifted at equal pitches.   The probe assembly according to claim 6, wherein the conductive portion in the vicinity of the terminal portion is provided with a curved portion.   The probe assembly according to claim 6, wherein the link mechanism and the terminal portion have a cantilever structure provided with a notch in the vicinity thereof.   2. The probe assembly according to claim 1, wherein when the copper foil is etched, a dummy portion is formed without removing portions other than the conductive portion, thereby forming a reinforcing member for the resin film.   The probe assembly according to claim 10, wherein an insulating adhesive is filled in a resin film surface between the conductive portion and the dummy portion.

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