JPH0518031U - IC chip inspection device - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To provide an inspection device that easily and accurately performs the characteristic inspection and burn-in inspection of an IC chip having a fine connection pad size and pitch. [Structure] An anisotropic conductive film 5 provided with a protruding electrode 8 penetrating an electrically insulating polymer film 7 at a position facing a connection pad 2 of an IC chip 1 to be inspected, and one end of the anisotropic conductive film 5. 8 is a printed circuit board 6 having a wiring pattern 9 which is located at a position facing 8 and has the other end spread outward and connected to the detection device.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an inspection device for inspecting the electrical characteristics of an IC chip, and more particularly to an inspection device for an IC chip that can be used for burn-in inspection because the dimensions and pitch of connection pads are made finer.

[0002]

[Prior Art]

 As various electronic devices such as word processors, personal computers, and memory cards become more compact with the progress of semiconductors and semiconductor-related technologies, IC chips without a resin mold equipped with a large number of integrated circuit elements have been added to these electronic devices. It is used. In recent years, various methods of directly mounting this IC chip on a circuit board have been studied. This is due to the high integration, weight reduction, and compactification of various electronic devices. The pitch of connection pads has become finer and finer due to the increased number and smaller dimensions.

[0003]

[Problems to be solved by the device]

 In order to inspect the electrical characteristics of such IC chips, generally, a pin-shaped probe, which has been widely used in the inspection of resin-molded integrated circuit elements, circuit components such as transistors and diodes, is used. It is used. For example, as shown in FIG. 3, the pin-shaped probe 4 fixed on the substrate 3 is brought into contact with the connection pad 2 of the IC chip 1 to be inspected, and the probe 4 is connected to an inspection measuring instrument (not shown).

However, as the pitch of the connection pads becomes finer, the probe becomes more expensive, and it is difficult to reduce the diameter and fine pitch of the probe that can be used for the inspection of the pitch of the connection pads of 0.3 mm or less. Since the tip of the connector has an acute angle, it is easy to damage the connection pads to be inspected.If there are many connection pads, it will take a long time to inspect unless they are connected at the same time. There are disadvantages such as not being able to add.

In addition, there is also a method of conducting an inspection using an anisotropic conductive rubber sheet in which metal wires are arranged in the thickness direction of a silicone rubber sheet, but this method allows fine pitching. Although it has the advantage that connection pads can be connected randomly at the same time, it generally requires a large connection load and has a problem of durability during repeated use, so the electrical characteristics of IC chips with fine pitch connection pads are It is hard to say that it has sufficient performance for inspection.

In view of the above drawbacks, the present invention can easily inspect the electrical characteristics and the like even if the connection pads of the IC chip are arranged at a pitch of 0.3 mm or less, and a large number of connection pads can be obtained with a low pressing force. The purpose of the present invention is to provide an IC chip inspection apparatus that can be connected simultaneously, and has durability because it does not damage the connection pads and is advantageous in terms of cost. Further, recent IC chips require a so-called burn-in test, which is a continuous current test in a high temperature atmosphere, and an IC chip inspection apparatus that can be used for this test is also provided.

[0007]

[Means for Solving the Problems]

 The present invention has solved the above-mentioned problems. This is an anisotropic conductive film in which a protruding electrode is provided through an electrically insulating polymer film at a position facing a connection pad of an IC chip to be inspected. An IC chip inspection device comprising a film and a printed circuit board having a wiring pattern in which one end faces the protruding electrode and the other end spreads outward and is connected to a detection device. It is what

Each connection pad of the IC chip to be inspected is a measuring device for inspecting external electrical characteristics from the protruding electrode of the anisotropic conductive film through the wiring pattern of the printed board, such as an LCR meter or an insulation resistance. It is connected to a measuring instrument.

Hereinafter, the IC chip inspection apparatus of the present invention will be described in detail with reference to the drawings. FIG. 1 (a) is an explanatory view showing the arrangement of the device of the present invention, and FIG. 1 (b) is a vertical cross-sectional view of the device in an inspected state. The IC chip 1 to be inspected is placed on an anisotropic conductive film 5, and The directional conductive film 5 is placed on the printed board 6. At this time, the protruding electrodes 8 penetrating the electrically insulating polymer film 7 are brought into contact with the connection pads 2 so as to face each other. The projecting electrodes 8 project from the upper and lower surfaces of the electrically insulating polymer film 7 to form the anisotropic conductive film 5. Since one end of the protruding electrode 8 is brought into contact with the connection pad 2 of the IC chip 1 and the other end is brought into contact with the wiring pattern 9 of the printed circuit board 6, the connection pad 2 and the wiring pattern 9 are connected via the protruding electrode 8. Are electrically connected, and the wiring pattern 9 is connected to a detection device (not shown). Note that FIG. 1 shows a case where the protruding electrodes are arranged only at positions facing the connection pads. It does not matter if the protruding electrode is provided at the position where the connection pad does not exist. However, in this case, it is necessary to take measures so that the protruding electrodes do not cause defective lateral conduction between the wiring patterns.

As the electrically insulating polymer film that constitutes this anisotropic conductive film, there are chemical loads due to various solvents used for providing through holes and protruding electrodes, and high temperature atmosphere during burn-in inspection. However, thermal stability with little dimensional change and sufficient mechanical strength with little dimensional change and loss of strength even after repeated use are required.

Therefore, as the polymer film suitable for the present invention, polyester film, polymethylmethacrylate film, polycarbonate film, polyarylate film, polyamide film, polyimide film, polyamideimide film, polyetherimide film, polyphenylene sulfide Examples include films, polyether sulfone films, polybalaponic acid films, etc. If the thickness is too thin, the handling property deteriorates, and it cannot withstand the thermal load during production, and if it is too thick, it penetrates the polymer film. Since it takes a long time to make a hole for forming the hole and to form a protruding electrode in the hole, the range is 5 to 500 μm, preferably 10 to 100 μm.

The protruding electrode is one in which one end is electrically connected to the connection pad of the IC chip to be inspected and the other end is electrically connected to the wiring pattern of the printed circuit board. To form the protruding electrode, a polymer film with a small diameter is used. A hole is made and a conductive bump electrode is formed in the obtained hole. The diameter of the holes is appropriately selected according to the size and pitch of the connection pads of the IC chip. Since the size of the connection pad of the recent IC chip is 50 to 100 μm square or less and the pitch is 100 to 200 μm, it is difficult to mechanically drill with a drill or the like to obtain a hole corresponding to this size. It is preferable that the hole portion of the polymer film is removed by etching with an aqueous alkaline solution or an organic solvent using a photoresist, or a method using a laser.

The bump electrode formed in the obtained hole electrically connects the connection pad of the IC chip and the wiring pattern, and therefore requires good conductivity. Therefore, it is preferable to use metal. Examples of the metal material that can be used include Au, Ag, Cu, Ni, and solder. These metals are formed into a desired protruding electrode shape by a plating method, and if necessary, they can be connected to a connection pad or a pattern electrode of an IC chip. In order to improve the electrical connectivity, the surface of the bump electrode may be coated with an alloy such as solder or a conductive adhesive.

Further, the protruding electrode needs to protrude from the surface of the polymer film, because the reason is to ensure the connectivity with the connection pad of the IC chip and the pattern electrode, and the protruding dimension is 2 μm or more. is necessary. The upper limit of the protrusion size is not particularly limited, but is preferably 50 μm or less. The reason for this is that if the protrusion size is made larger than this, the time required for forming a hole in the polymer film or forming the protrusion electrode is reduced. This is because the cost will increase. Further, it is more preferable that both ends of the protruding electrode are laterally extended so as not to be separated from the electrically insulating polymer film and be formed into a rivet shape, but if they are projected from the surface of the polymer film, the shape is not particularly limited. Therefore, it may have a straight rod shape as shown in FIG. 2 (a) or a rivet shape with a square head as shown in FIG. 2 (b).

The printed circuit board used in the present invention is provided with a wiring pattern for connecting to the IC chip and a detection device for external electrical characteristics and the like through the protruding electrodes arranged on the anisotropic conductive film. However, the wiring pattern needs to be made of a material having good conductivity, and Cu is generally used, but other metals such as Au, Ag, and Sn may be used, and Cu, Au, Sn, You may give plating such as solder. If the thickness is too thin, the conductivity is lowered and the wire breaks. On the other hand, if the thickness is too thick, it becomes rigid and difficult to handle and the cost becomes high. Therefore, the thickness may be 2 to 500 μm, preferably 5 to 200 μm. .

In addition to copper-clad glass cloth epoxy resin laminated board, copper-clad glass cloth polyimide resin laminated board, etc., copper-clad polyimide resin film (so-called flexible printed circuit board), It is an ITO glass substrate or the like. One end of the wiring pattern of the printed circuit board should be a pattern electrode facing the connection pad of the IC chip, and the other end should spread out to the outside to facilitate electrical connection with the measuring instrument for inspection.

As a method of aligning and fixing the anisotropic conductive film on the printed circuit board of the present invention, the anisotropic conductive film 5 is provided on the anisotropic conductive film 5 as shown in FIG. The positioning pin 11 for positioning on the printed circuit board 6 may be formed so as to be engaged with the positioning hole 10. Alternatively, an electrically insulating adhesive may be inserted and fixed in the gap between the anisotropically conductive film and the printed circuit board. The adhesive used here may be thermosetting resin, thermoplastic resin, or UV curing. And the like, and may be a mixture thereof. However, it is needless to say that it is necessary to suppress the mixture of components that deteriorate or change the quality of these materials as much as possible because the adhesive is in contact with the protruding electrodes or the pattern electrodes.

[0018]

【Example】

 A laser beam emitted from a YAG laser is applied to the polyparabanic acid resin layer of a laminated plate made of a copper foil having a thickness of 70 μm and a polyparabanic acid resin having a thickness of 50 μm, and the polyparabanic acid resin layer is positioned at a position facing the connection pad of the IC chip. After drilling 150 fine holes with a diameter of 50 μm and etching away the copper foil at the bottom of the holes to a depth of 10 μm with an aqueous solution of ferric chloride, immersing it in a Ni plating bath to deposit Ni inside the holes After forming a protruding electrode until it protruded 20 μm from the surface of the acid film, it was taken out of the Ni plating bath and immersed in an etching solution to completely remove the remaining copper foil and produce an anisotropic conductive film. . The protruding electrodes project from the anisotropic conductive film at both upper and lower ends, and are rivet-shaped protruding in the lateral direction, so that they do not separate from the polymer film.

Next, the anisotropic conductive film is positioned and placed on a printed circuit board having a 70 μm thick wiring pattern and positioning pins, and the protruding electrodes of the anisotropic conductive film are connected to the IC chip. Connected to the pad. Next, when the wiring pattern of the printed circuit board was connected to an external detector and the connection resistance of 150 protruding electrodes was measured, all were 100 mΩ or less, and the insulation resistance between adjacent protruding electrodes was 10 ¹⁰ Ω or more. The operation was repeated 50 times at room temperature, but no defects such as device failure or unstable connection resistance occurred. Furthermore, there was no change even after repeating the operation of standing at 80 ° C. for 96 hours 10 times.

[0020]

[Effect of the device]

 Since the present invention uses the anisotropic conductive film having a large number of protruding electrodes at the positions facing the connection pads of the IC chip to be inspected, it is possible to connect a large number of connection pads at the same time and reduce the inspection time. Since the protruding electrode has a rivet shape rather than a pin shape, it does not damage the connection pad and can be manufactured at a lower cost than the conventional inspection apparatus, so that the cost can be reduced accordingly.

Further, since it is possible to cope with an increase in the number of IC chip connection pads, a reduction in size, and a reduction in pitch due to technological trends such as high-density mounting and cost reduction, the IC chip of the present invention can be used. Using the inspection equipment, it is possible to carry out burn-in inspection of IC chips that cannot be handled by conventional inspection equipment.

Further, in the IC chip inspection apparatus according to the present invention, the printed circuit board and the anisotropic conductive film can be easily fixed in the correct positions with alignment pins or an adhesive. The projecting electrodes formed to project can be reliably connected to the connection pads of the IC chip, and if they are connected to a device that detects external electrical characteristics, such as an insulation resistance meter, it can be easily and reliably electrically connected. The inspection can be done.

[Brief description of drawings]

FIG. 1A is an explanatory view showing the arrangement of each part of an inspection device of the present invention, and FIG. 1B is a longitudinal sectional view of the assembled inspection device of the present invention.

FIG. 2A is a vertical sectional view of another example of the anisotropic conductive film used in the inspection apparatus of the present invention, and FIG.

FIG. 3 is a vertical sectional view of a conventional inspection device.

[Explanation of symbols]

 1 IC Chip 2 Connection Pad 3 Board 4 Probe 5 Anisotropic Conductive Film 6 Printed Circuit Board 7 Polymer Film 8 Projection Electrode 9 Wiring Pattern 10 Positioning Hole 11 Positioning Pin

Claims (1)

[Scope of utility model registration request] 1. An anisotropic conductive film having a protruding electrode penetrating an electrically insulating polymer film at a position facing a connection pad of an IC chip to be inspected, and one end thereof facing the protruding electrode. An IC chip inspecting device, characterized in that it comprises a printed circuit board having a wiring pattern that is located at a position and the other end thereof spreads outward and is connected to a detecting device.