JP2010219391A - Method of manufacturing membrane ring with bump and wafer batch contact board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve an yield by improving the positional precision of a bump in a membrane ring with the bump. <P>SOLUTION: On an aluminum plate 13 warmed at 100°C, a laminate film 28 comprised of copper foil and a polyimide film is formed while bringing a copper foil side into contact with the aluminum plate 13 and a rigid ring 23 coated with a thermosetting adhesive and comprised of SiC and a ring-shaped SUS weight stone 14 (whose weight is about 2.5 kg) are sequentially installed thereon. The laminate film 28, the ring 23 and the weight stone 14 are then warmed while being left for about five minutes until a temperature reaches 100°C. Next, temperatures of the laminate film 28, the ring 23 and the weight stone 14 are elevated up to 120°C gradually for about five minutes by a heater controlled by a temperature adjusting means. They are finally left at 120°C for 45 minutes to harden the thermosetting adhesive, thereby adhering the laminate film 28 and the ring 23. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wafer batch contact board for performing a burn-in test on wafers at once and a method for manufacturing a membrane ring with bumps which are components constituting the wafer contact board.

  Inspection of a plurality of semiconductor devices formed on a wafer is roughly classified into product inspection (electrical characteristic test) using a probe card and burn-in test which is a reliability test performed thereafter. The burn-in test is one of screening tests performed to remove a semiconductor device having an inherent defect or a device causing a failure depending on time and stress from manufacturing variations. While the probe card inspection is an electrical characteristic test of the manufactured device, the burn-in test is a thermal acceleration test.

  The burn-in test is a cost in a method (one-chip burn-in system) in which a wafer is cut into chips by dicing and packaged one by one after an electrical characteristic test performed for each chip by a probe card. The feasibility is poor. Therefore, as shown in Patent Document 1, development and practical application of a wafer batch contact board (burn-in board) for performing a burn-in test of a large number of semiconductor devices formed on a wafer all at once are being promoted. Wafer batch burn-in system using wafer batch contact board is not only highly feasible in terms of cost, but also an important technology to enable the latest technological flow such as bare chip shipment and bare chip mounting. . The wafer batch contact board is different from the conventional probe card in that the wafer batch contact board is used for the wafer batch inspection and the heating test. When the wafer batch contact board is put into practical use, it becomes possible to perform product inspection (electrical characteristic test) which has been conventionally performed by a probe card in a wafer batch.

The wafer batch contact board usually has a structure in which a membrane ring with bumps is fixed to a multilayer wiring board via an anisotropic conductive rubber sheet. The membrane ring with bumps includes a ring, a bump provided on one surface of the insulating thin film stretched over the ring, and a pad provided on the other surface electrically connected to the bump. It is. The bumps on the membrane ring with bumps are in contact with the device pads on the semiconductor wafer, and the power supply voltage and burn-in test signal applied from the power supply and signal source connected to the conductive layer of the multilayer wiring board are anisotropic. It is sent to the pad of the membrane ring with bumps through the conductive rubber sheet. A bump conducting to the pad is sent to a semiconductor device on the wafer, and a burn-in test is performed.
As a manufacturing method of a membrane ring with bumps, for example, as shown in Patent Document 2, a laminated film formed by laminating a polyimide film (insulating thin film) and a copper foil is formed into a ceramic ring with a thermosetting adhesive. Next, bump holes are formed by laser processing for bump formation on the polyimide film of the laminated film, bumps are provided by bump plating, and finally the copper foil of the laminated film is patterned so as to be electrically connected to the bumps To form a pad.

Japanese Patent Laid-Open No. 7-231019 Japanese Patent No. 3645095

As a method for bonding the ceramic ring to the laminated film, a method of bonding the laminated film and the rigid ring with a thermosetting adhesive is known. The laminated film is stretched by heat, and then the temperature is lowered and contracted, whereby the laminated film is stretched with a certain tension. Depending on the bonding conditions, wrinkles and distortion occur in the laminated film. When wrinkles or distortion occurs, the tension becomes non-uniform in the surface, and when forming a bump hole by a laser that is a subsequent process, the bump hole is formed at a position deviated from the design coordinates.
In addition, when the temperature rise time is long as in the case where the temperature is raised from room temperature, the gas generated when the adhesive undergoes condensation polymerization becomes bubbles between the ring and the laminated film, and the bubbles are adhered without being removed. Sometimes. If bubbles remain, the bonding area between the ring and the laminated film decreases, and a strong bond cannot be obtained.
On the other hand, since the thermosetting adhesive has a distribution in the curing temperature, it is necessary to bond at a temperature (applying temperature) somewhat higher than the peak curing temperature. However, if the pasting temperature is too high, wrinkles are remarkably generated, and there is a problem that waviness occurs in the laminated film under the ring.
As described above, there is a problem that uneven tension is caused by the wrinkles of the laminated film and the bump position accuracy is lowered. If the bump position accuracy is low, poor contact with the pads on the wafer occurs, leading to a decrease in the yield of the membrane ring with bumps.

  A first aspect of the present invention has been made in view of the above circumstances, and a method of manufacturing a membrane ring with bumps, in which the ring and the laminated film are well bonded, the positional accuracy in bump formation is high, and the yield can be improved. The purpose is to provide. A second object of the present invention is to provide a highly reliable wafer batch contact board.

In order to solve the above problems, the present invention has the following configuration.
(Configuration 1)
A method of manufacturing a membrane ring with bumps used for performing a burn-in test of a plurality of semiconductor devices formed on a wafer at one time,
A temperature-controllable mounting table, which is 10 ° C. to 30 ° C. lower than the curing temperature of a thermosetting adhesive used when manufacturing the bumped membrane ring and curing at a temperature equal to or higher than the set temperature of the burn-in test. A step of temperature;
The film is uniformly spread on a mounting table controlled at the first temperature, and a thermosetting adhesive is interposed between the film and a ring for supporting the film in a developed state, and the film And a preheating step of heating the ring to the first temperature;
After the preheating step, heating the film and the ring at a second temperature equal to or higher than the curing temperature of the thermosetting adhesive;
Curing the thermosetting adhesive at the second temperature to bond the film and the ring;
Forming bumps made of a conductive material on one surface of the film, and forming pads made of a conductive material electrically connected to the bumps on the other surface. Membrane ring manufacturing method.

(Configuration 2)
The method for producing a membrane ring with bumps according to Configuration 1, wherein the temperature rise time from the first temperature to the second temperature is 5 minutes or less.

(Configuration 3)
The film is a laminated film obtained by bonding a polyimide film and a copper foil, and the film and the ring are placed on the mounting table so that the copper foil and the mounting table are in contact with each other. Fix with the thermosetting adhesive,
After forming a bump hole until the copper foil is exposed to the polyimide film, forming the hemispherical bump on the polyimide film surface while filling the bump hole,
3. The method for producing a membrane with bumps according to Configuration 1 or 2, wherein the pads are formed by patterning the copper foil.

(Configuration 4)
A membrane ring with bumps produced by the method according to any one of configurations 1 to 3,
What is claimed is: 1. A wafer batch contact board, comprising: a multilayer wiring board in which a plurality of conductive layers are laminated on an insulating layer through an insulating layer.

  According to the said structure 1, after warming a mounting base to 1st temperature, a film is spread | deployed uniformly and a thermosetting adhesive agent is interposed between the rings for supporting in the state which expand | deployed this film. After preheating the film and ring to the first temperature, the temperature is raised to a second temperature equal to or higher than the curing temperature of the thermosetting adhesive to cure the adhesive. It is difficult for wrinkles to occur, and the film can be stretched with a substantially uniform tension. Therefore, the bump position accuracy can be improved to ± 10 μm. In addition, by setting the first temperature to a first temperature that is 10 ° C. to 30 ° C. lower than the curing temperature of the thermosetting adhesive, it is possible to prevent generation of bubbles between the ring and the film, Adhesion can be obtained. In addition, it is not necessary to lower the temperature to room temperature in order to attach another film to the ring, so that the time can be shortened and productivity is improved.

  According to the above-described configuration 2, since the temperature rising time from the first temperature to the second temperature is within 5 minutes, the generation of wrinkles can be further reduced, so that the laminated film can be formed with substantially uniform tension. The bumps can be stretched, and the bump position accuracy can be further improved within ± 10 μm.

According to the configuration 3, since the tension of the laminated film can be stretched almost uniformly with respect to the ring, it is possible to improve the positional accuracy of the bumps and further suppress the height variation of the bumps. it can. Moreover, since the patterning of the copper foil is satisfactorily performed, the positional accuracy of the pad can be improved.
As described above, according to the present invention, the rigid ring and the laminated film are favorably bonded, the positional accuracy in bump formation is high, and the yield can be improved.

  According to the above configuration 4, since the membrane ring with bumps with high bump position accuracy is used, a highly reliable wafer batch contact board can be obtained.

The schematic sectional drawing which shows the adhesion process of the laminated | multilayer film and ring in the manufacture process of the membrane ring with a bump which is one Embodiment of this invention. The schematic sectional drawing which shows the formation process of the bump and pad in the manufacture process of the membrane ring with a bump which is one Embodiment of this invention. The graph which shows the adhesion conditions of an Example and a comparative example Diagram showing measurement position in plane Schematic sectional view showing a wafer batch contact board

The manufacturing method of the membrane ring with bump which is the Example of this invention is demonstrated referring FIG. 1 and FIG. FIG. 1 is a schematic cross-sectional view showing a process of producing a membrane ring (a laminated film bonded to a ring) in the process of manufacturing a membrane ring with bumps. FIG. 2 is a schematic cross-sectional view showing a process of providing bumps and pads on the membrane ring.
First, a process for producing a membrane ring will be described with reference to FIG. As shown in FIG. 1 (a), an aluminum plate comprising a temperature adjusting means 11 and a heater 12 controlled in temperature by the temperature adjusting means 11 and having a high flatness and capable of being held at a uniform temperature. 13 is prepared. The aluminum plate 13 is heated to 100 ° C. (first temperature) by the heater 12 controlled by the temperature adjusting means. As the thermosetting adhesive, Bond High Chip HT-100L (main agent: curing agent = 4: 1) (manufactured by Konishi Co., Ltd.) is used. Since the heat curing temperature of this adhesive is known to be 115 ° C. from thermal analysis, the first temperature is set to 100 ° C., which is 15 ° C. lower than the heat curing temperature.

Next, as shown in FIG.1 (b), on the aluminum plate 13, the laminated film 28 which consists of copper foil and a polyimide film is installed in contact with the aluminum plate 13 on the copper foil side, A rigid ring 23 (diameter 8 inches, thickness 2 mm) made of SiC with a thin and uniform thermosetting adhesive (50 μm to 100 μm) and a ring-shaped SUS stone 14 (weight) About 2.5 kg) will be installed sequentially. Then, the laminated film 28, the ring 23, and the weight 14 are left to warm for about 5 minutes until the temperature reaches 100 ° C. This time is sufficient to make the temperature of the laminated film 28, the ring 23, and the weight 14 uniformly 100 ° C. By setting the temperature of the laminated film 28, the ring 23 and the weight stone 14 to the same temperature, the temperature difference between the respective members can be eliminated, and the generation of wrinkles can be prevented.
The laminated film 28 is obtained by forming a copper foil with a thickness of 18 μm on a polyimide film with a thickness of 25 μm by sputtering or plating. In addition, the material of the laminated film 28, a formation method, thickness, etc. can be selected suitably.

Next, the temperature of the laminated film 28, the ring 23 and the weight 14 is gradually raised to 120 ° C. over about 5 minutes by a heater controlled by the temperature adjusting means.
Finally, it is left at 120 ° C. for 45 minutes to cure the thermosetting adhesive and bond the laminated film 28 and the ring 23 together. The tension of the laminated film was 0.5 kg / cm ² .

In this embodiment, the thermosetting adhesive is not limited to the above, and acrylic, polyimide and epoxy adhesives can be used, and has a thermosetting temperature higher than the set temperature of the burn-in test. Is used as appropriate.
In addition, the first temperature is set to 100 ° C., but is not limited to this, and is preferably selected as appropriate at a temperature that is 10 ° C. to 30 ° C. lower than the curing temperature of the thermosetting adhesive. When the temperature is lower than the curing temperature by less than 10 ° C., the temperature is close to the curing temperature, so that the curing starts before the temperatures of the laminated film, the ring, and the weight are uniform. Further, a temperature lower by 30 ° C. than the curing temperature is not preferable because it takes time until the temperature of the laminated film, ring and weight is uniform, and bubbles are easily generated.

  In addition, the second temperature (adhesion temperature) is 120 ° C., but is not limited to this, and it may be at least the curing temperature of the thermosetting adhesive, and the preferred temperature is that of the thermosetting adhesive. A temperature higher by 5 ° C. to 20 ° C. is preferable depending on the curing temperature. When the temperature is higher than 5 ° C. than the curing temperature, the film is not completely cured and adhesion is not strong.

  Further, instead of the SiC ring, a ring made of ceramic, low expansion glass, metal, or other material having a thermal expansion coefficient close to that of SiN, SiCN, invar nickel, or other Si may be used.

  In addition, as the weight, a SUS ring-shaped one is used, but an aluminum plate with high flatness may be used.

Next, a process of forming bumps and pads on the membrane ring will be described with reference to FIG.
What finished the said heat-bonding process is cooled to normal temperature, and is shrunk to the state before a heating. The laminated film 28 outside the ring 23 is cut and removed along the outer periphery of the ring with a cutter (FIGS. 2A and 2B).
Next, as shown in FIG. 2C, Ni and Au plating (thickness of 1 to 2 μm) are sequentially applied (not shown) on the copper foil 21 of the laminated film 28 to form the alignment mark 24.
Next, as shown in FIG. 2D, a bump hole 25 having a diameter of about 30 μm is formed at a predetermined position of the polyimide film 22 using an excimer laser.
Next, after protecting the surface of the copper foil 21 from being plated, one of the electrodes for plating is connected to the copper foil 21, and Ni is electroplated on the bump hole. As shown in FIG. 2 (e), after the plating grows so as to fill the bump holes, when it reaches the surface of the polyimide film, it isotropically spreads and grows into a substantially hemispherical shape. Bumps 26 made of Ni alloy are formed. In this case, plating is performed until the height of the bump 26 reaches about 20 to 30 μm. Thereafter, an electroplating layer made of Au is formed on the surface of the bump 26 in order to stabilize the contact resistance between the bump 26 and the pad on the semiconductor wafer. (Not shown).
Next, a resist is applied to the entire surface of the copper foil, and the resist other than the portion where the pad is to be formed is removed by exposure and development to form a resist pattern in the pad forming portion.
Finally, as shown in FIG. 2 (f), the Au film is etched with an iodine / potassium iodide aqueous solution, and the thin Ni film and Cu film existing between Au and the copper foil are removed with an aqueous ferric chloride solution or the like. Etching is performed with, and after rinsing well, the resist is peeled off to form a metal pad 21a made of Au / Ni / Cu with a diameter of about 150 μm. At this time, it is desirable to use a spray method for etching because there is little side etching. Through the above steps, a membrane ring with bumps is produced.

Next, details of the present invention will be described using examples and comparative examples.
A membrane ring (the one in which a laminated film is stretched around the ring) obtained in the steps up to FIG. Next, through the steps of FIG. 2C to FIG. 2F, bumps and pads were formed on the membrane ring to produce a membrane ring with bumps, and the bump position accuracy and position accuracy yield were evaluated. FIG. 3 shows a graph of the bonding conditions of the example and the comparative example.
Example 1

As shown in FIG. 3, the membrane ring with bumps of Example 1 was first made uniform at 100 ° C. for 5 minutes, and the temperature of the laminated film, ring and weight was gradually increased to 120 ° C. over the next 5 minutes, Finally, the thermosetting adhesive was cured at 120 ° C. for 45 minutes to bond the laminated film and the ring.
(Example 2)

As shown in FIG. 3, the membrane ring with bumps of Example 2 was first made uniform at 100 ° C. for 5 minutes, and the temperature of the laminated film, ring and weight was gradually increased to 130 ° C. in the next 8 minutes. Finally, the thermosetting adhesive was completely cured at 130 ° C. for 45 minutes to bond the laminated film and the ring.
(Comparative Example 1)

The membrane ring with bumps of Comparative Example 1 was prepared by placing a laminated film made of copper foil and polyimide film on an aluminum plate at 140 ° C. with the copper foil side in contact with the aluminum plate in the production process of the above example. On top of that, a ring made of SiC with a thermosetting adhesive thinly and evenly applied and a ring-shaped SUS stone of the same size are installed in sequence, and the adhesive is cured for 30 minutes to adhere It is what I did.
(Comparative Example 2)

The membrane ring with bumps of Comparative Example 1 was prepared by placing a laminated film made of copper foil and a polyimide film on an aluminum plate set at 150 ° C. with the copper foil side in contact with the aluminum plate in the manufacturing process of the above example. On top of that, a ring made of SiC with a thermosetting adhesive thinly and evenly applied and a ring-shaped SUS stone of the same size are installed in sequence, and the adhesive is cured for 30 minutes to adhere It is what I did.
(Evaluation)

(Evaluation: Bump position accuracy)
Bumps and pads were formed on the membrane rings produced in Examples 1 and 2 and Comparative Examples 1 and 2 by the production method shown in FIG. 2 to produce a membrane ring with bumps.
FIG. 5 is a diagram showing measurement positions of in-plane bump position accuracy. As shown in FIG. 4 (a), in the obtained membrane ring with bumps, 25 points in the plane were measured to determine how much the position of the bumps actually formed deviated from the design position. As shown in FIG. 4B, the center of the square coordinates in the figure is the design position, and the distance d (μm) from the center to the bump position actually formed was measured.
In Example 1, the bump formation positions were almost as designed, and 25 position shifts (the average value of the distance d was ± 7 μm, and the yield of position accuracy was 100%.
In Example 2, the average value of the positional deviation (distance d) at 25 points was ± 10 μm. The yield of positional accuracy was 80%.
In Comparative Example 1, the average value of the positional deviation (distance d) at 25 points was ± 12 μm. The yield of positional accuracy was 60%.
In Comparative Example 2, the average value of the positional deviation (distance d) at 25 points was ± 15 μm. The yield of positional accuracy was 40%.

Next, an embodiment of the wafer batch contact board of the present invention will be described.
FIG. 5 shows a schematic configuration diagram of the wafer batch contact board of the present invention.
As shown in FIG. 5, the wafer batch contact board includes a membrane ring with bumps, a multilayer wiring substrate 60 in which a plurality of wiring layers are laminated via an insulating layer, a membrane ring with bumps 20 and a multilayer wiring substrate 60. And an anisotropic conductive rubber sheet 72 that electrically connects the two. The anisotropic conductive rubber sheet 72 is bonded to a predetermined position of the multilayer wiring board, and then the multilayer wiring board with anisotropic conductive rubber sheet and the membrane ring 20 with bumps are positioned so that the pad electrode does not come off. After being combined, they can be bonded together.

  The membrane ring 20 with bumps includes a ring 23, a bump 26 provided on one surface of the polyimide film 22 stretched over the ring, and a pad 21a provided on the other surface electrically connected to the bump. With. In the membrane ring with bumps, this number is multiplied by the number of chips corresponding to pads 82 (about 600 to 1000 pins) formed on the periphery or center line of each semiconductor chip on the semiconductor wafer 81. Bumps are formed on the polyimide film.

  The multilayer wiring board 60 has a wiring layer for providing a power supply voltage and a predetermined burn-in test signal as a laminated structure. A wiring layer is laminated on an insulating substrate and formed into a desired pattern by a well-known lithography method, and then an insulating layer is laminated, contact holes are formed in the insulating layer by a well-known lithography method, and then another layer is formed thereon. By laminating these wiring layers, electrical connection is established with the lower conductive layer through the contact hole. By performing this series of processes a plurality of times, a plurality of wirings for sending electrical signals to a large number of pads on the wafer are provided. As the insulating base material, it is desirable to use low expansion non-alkali glass (for example, NA40: manufactured by HOYA). As the insulating layer, for example, polyimide formed by applying a polyimide precursor and imidizing by heat treatment is desirable. Further, it is desirable to use a Ni / Cu / Cr laminated structure as the wiring layer.

  The anisotropic conductive rubber sheet 72 is made of an elastic body having conductivity only in a direction perpendicular to the main surface, for example, silicon resin, and metal particles are embedded in the pad electrode portion 73 along the conduction direction. . By electrically connecting the terminals on the multilayer wiring board and the pads 21a of the membrane ring with bumps and pressing the pads 21a on the membrane with bumps, the unevenness on the surface of the semiconductor wafer and the variation in bump height are absorbed. The pads 82 on the semiconductor wafer 81 and the bumps 26 on the polyimide film are securely connected.

A power source voltage and a burn-in test signal applied from a power source and a signal source connected to the wiring layer of the multilayer wiring board are sent to the pad 21a of the membrane ring with bumps through the anisotropic conductive rubber sheet, and conducted to the pad 21a. The bump 26 is sent to the semiconductor device on the wafer, and a burn-in test is performed.
Since the wafer batch contact board manufactured as described above has high pad positional accuracy, contact failure in the burn-in test can be prevented, and a highly reliable one can be obtained. Further, in addition to being used as a wafer batch contact board used in a burn-in test, it can also be used as a probe card for characteristic inspection.

DESCRIPTION OF SYMBOLS 11 Temperature control means 12 Heater 13 Aluminum plate 14 Weight stone 20 Bumped membrane ring 21 Copper foil 22 Polyimide film 23 Rigid ring 24 Alignment mark 25 Bump hole 26 Bump 28 Laminated film 31 Hot plate 41 Weight stone 51, 52 Polarizing plate 53 Membrane ring 60 multilayer wiring board 72 anisotropic conductive rubber sheet 81 semiconductor wafer 82 pad

Claims (4)

A method of manufacturing a membrane ring with bumps used for performing a burn-in test of a plurality of semiconductor devices formed on a wafer at one time,
A temperature-controllable mounting table is used when manufacturing the bumped membrane ring, and is a first lower by 10 ° C. to 30 ° C. than the curing temperature of the thermosetting adhesive that cures at a temperature higher than the set temperature of the burn-in test. A step of temperature;
The film is uniformly spread on a mounting table controlled at the first temperature, and a thermosetting adhesive is interposed between the film and a ring for supporting the film in the spread state, and the film And a preheating step of heating the ring to the first temperature;
After the preheating step, heating the film and the ring at a second temperature equal to or higher than the curing temperature of the thermosetting adhesive;
Curing the thermosetting adhesive at the second temperature to bond the film and the ring;
Forming bumps made of a conductive material on one surface of the film, and forming pads made of a conductive material electrically connected to the bumps on the other surface. Membrane ring manufacturing method.   The method for producing a membrane ring with bumps according to claim 1, wherein the temperature rising time from the first temperature to the second temperature is within 5 minutes. The film is a laminated film obtained by bonding a polyimide film and a copper foil, and the film and the ring are placed on the mounting table so that the copper foil and the mounting table are in contact with each other. Fix with the thermosetting adhesive,
After forming a bump hole until the copper foil is exposed to the polyimide film, forming the hemispherical bump on the polyimide film surface while filling the bump hole,
The method for producing a membrane with bumps according to claim 1, wherein the pad is formed by patterning the copper foil. A membrane ring with bumps manufactured by the method according to any one of claims 1 to 3,
What is claimed is: 1. A wafer batch contact board, comprising: a multilayer wiring board in which a plurality of conductive layers are laminated on an insulating layer through an insulating layer.

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