JP6691998B1 - Semiconductor device manufacturing method and semiconductor device manufacturing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dramatically increase the yield by making a work in which a plurality of semiconductor chips are mounted on a substrate conductive and reworkable through an anisotropic conductive paste having conductive particles and a thermosetting adhesive. Provided is a semiconductor device manufacturing apparatus that can be improved. A semiconductor device manufacturing apparatus 1 has a configuration including a first reflow furnace 3 that heats a work 90a and a control unit 2, and the first reflow furnace 3 extends from an inlet side to a heating zone 3b. The first conveyor 31 is provided, and subsequently, the second conveyor 32 is provided from the cooling zone 3c to the outlet side. The control unit 2 controls the workpiece 90a for the first conveyor 31 and the second conveyor 32. Is conveyed to the heating zone 3b to melt the solder, and then the work 90a is conveyed to the cooling zone 3c to cure the solder so that the work 90a can be energized and reworked. .. [Selection diagram] Figure 1

Description

  The present invention relates to a semiconductor device manufacturing method and a semiconductor device manufacturing apparatus.

  In recent years, with the miniaturization and high-density mounting of semiconductor chips, the importance of flip chip bonding technology using anisotropic conductive paste (ACP) or anisotropic conductive film (ACF) is increasing. The anisotropic conductive paste contains conductive particles and a binder, and a thermosetting adhesive such as an epoxy resin is used as a binder in consideration of high temperature characteristics and high adhesive strength.

  Conventionally, there has been proposed a manufacturing method in which a plurality of LED elements are heated via a anisotropic conductive paste while pressing a work mounted on a mounting surface of a substrate (Patent Document 1: Japanese Patent No. 6565902). In addition, a manufacturing method has been proposed in which the bypass wiring pattern is disconnected by connecting the LED chip to a portion of the substrate where the bypass wiring pattern is formed through an anisotropic conductive paste (Patent Document 2: Patent). No. 6147645). A reflow furnace that heats a work while conveying the work by a conveyor is known (Patent Document 3: Japanese Patent No. 4818952).

Japanese Patent No. 6565902 Japanese Patent No. 6147645 Japanese Patent No. 4818952

  As an example, as a backlight for a high-precision display device, there is a semiconductor device in which a large number of semiconductor chips with a width dimension of the order of 0.1 [mm] are mounted on a matrix substrate. In this case, if the work is heated while being pressurized as in Patent Document 1, defective products due to misalignment of semiconductor chips, stress distortion and the like are likely to occur. Further, when a substrate on which a bypass wiring pattern is formed as in Patent Document 2 is used, it becomes difficult to mount semiconductor chips at high density. In particular, when an anisotropic conductive paste containing conductive particles and a thermosetting adhesive is used, rework becomes impossible when the thermosetting adhesive is thermoset. However, Patent Documents 1 to 3 do not mention rework of defective products.

  The present invention has been made in view of the above circumstances, and makes it possible to energize and rework a work in which a plurality of semiconductor chips are mounted on a substrate through an anisotropic conductive paste having conductive particles and a thermosetting adhesive. By doing so, it is an object of the present invention to provide a semiconductor device manufacturing method and a semiconductor device manufacturing apparatus capable of dramatically increasing the yield in a semiconductor device that requires a high-density mounting technique.

  As one embodiment, the above-mentioned problems are solved by the solution means disclosed below.

A method for manufacturing a semiconductor device according to the present invention is a method in which an anisotropic conductive paste having conductive particles dispersed in an uncured thermosetting adhesive is transferred to a semiconductor chip and the semiconductor chip is flip-chip mounted by a flip chip mounting technique. a mounting step of mounting the substrate, a configuration having a first heat treatment step in which a plurality of said semiconductor chip is heated by the first reflow furnace onboard work on the substrate via the anisotropic conductive paste The first reflow furnace has a heating zone set to a melting temperature of the solder contained in the conductive particles or higher, a cooling zone set to a temperature lower than the melting temperature of the solder, and an inlet side to the heating zone. A first conveyor provided over the second conveyor and a second conveyor provided over the outlet side from the cooling zone, and the first conveyor and the second conveyor are provided. Wherein it work a configuration for passing the first reflow furnace below the curing time of the thermosetting adhesive, the first heat treatment step, the pitch in the first heating zone definitive the workpiece to the heating zone I The work is heated by a temperature rising curve having an average value of 4 to 8 ° C./sec in the first heating zone by being conveyed and retained by feeding, and then the work is heated in the second heating zone in the heating zone. To convey the work to the cooling zone and cure the solder so that the work can be energized and reworkable. Is characterized by.
In the first heat treatment step, the work is heated in the first heating zone for 20 to 40 seconds until it reaches a peak temperature, and the work is maintained in the second heating zone at the peak temperature. It is preferable that the work is heated for 5 to 30 seconds and then the work is cooled in the cooling zone. As an example, the semiconductor chip is an LED, and after the first heat treatment step, a continuity test step of conducting a continuity test on the work, and a defective conduction product is detected from the LEDs in the continuity test step. In this case, a defective product removing step of removing the defective conductive product by a defective product removing machine, and removing the defective conductive product by transferring the anisotropic conductive paste to a new LED instead of the defective conductive product. The re-mounting step of mounting the re-mounting part on a fixed part, and the defective product removing step re-melts the solder by sucking with a vacuum suction head while heating the mounting part of the defective conduction product in a non-contact manner. Then, the thermosetting adhesive of the defective connection and the connecting portion is removed from the substrate. As an example, after the remounting step, the first heat treatment step and the continuity test step are repeated until the defective continuity product is no longer detected, and the continuity test step determines whether or not the LED is turned on. The position of the defective conduction product is specified by storing the data in association with the arrangement data by the storage means.

  According to this configuration, since the solder in the anisotropic conductive paste is hardened, it is possible to detect a defective conduction product among the plurality of semiconductor chips mounted on the substrate by energizing the solder. Moreover, since the thermosetting adhesive in the anisotropic conductive paste is in a gel state for less than the curing time, it is possible to easily remove defective conductive products from the plurality of semiconductor chips mounted on the substrate and perform rework. Here, for the curing time of the thermosetting adhesive in the anisotropic conductive paste, for example, the curing conditions recommended by the material manufacturer can be applied, and the curing time of the thermosetting adhesive in the anisotropic conductive paste can be applied. The curing condition in which the gelling time of less than is calculated based on the experimental data is applicable, or the curing condition derived by the combination thereof is applicable.

A semiconductor device manufacturing apparatus according to the present invention comprises a coating machine for transferring an anisotropic conductive paste having conductive particles dispersed in an uncured thermosetting adhesive to a semiconductor chip and a flip chip mounting of the semiconductor chip. a mounter for mounting to a substrate by techniques, a plurality of the semiconductor chip through the anisotropic conductive paste have a configuration having a first reflow furnace and a control unit for heating the onboard work on the substrate The first reflow furnace has a heating zone set to a melting temperature of the solder contained in the conductive particles or higher, a cooling zone set to a temperature lower than the melting temperature of the solder, and an inlet side to the heating zone. A first conveyor provided over the cooling zone and a second conveyor provided over the outlet side from the cooling zone, and the work is performed by the first conveyor and the second conveyor. Wherein a thermosetting adhesive construction for passing the first reflow furnace below the curing time, the position between said first conveyor and said second conveyor, wherein the workpiece from the first conveyor second presser rollers in contact with the upper surface of the substrate is provided when transferred to the conveyor, wherein the control unit, the in be retained are transported by a pitch feed into the first heating zone definitive the workpiece to the heating zone Heating the work in the first heating zone with a temperature rising curve having an average value of 4 to 8 ° C./second, and then conveying the work to the second heating zone in the heating zone by pitch feed to make it stay there. in by melting the solder, then it, said conveys the workpiece to the cooling zone to cure the solder is energizable and configured to perform a control to rework ready the workpiece And it features.
The pressing roller is configured such that the shaft is rotatably supported on a shaft so that the roller can rotate at a predetermined interval, and the pressing roller is in contact with a position avoiding the mounting surface of the substrate due to its own weight. The work is heated in the zone for 20 to 40 seconds until the peak temperature is reached, and the work is heated in the second heating zone for 5 to 30 seconds so that the peak temperature is maintained, followed by the cooling. It is preferable that the zone is controlled to cool the work. As an example, the semiconductor chip is an LED, and a continuity tester that conducts a continuity test on the work and a continuity tester that removes a defective continuity product from the LEDs are detected. The defective product removing machine includes a defective product removing machine, which reheats the solder by sucking with a vacuum suction head while heating the mounting location of the defective conductive product in a non-contact manner, thereby causing the conductive failure. The non-defective product and the thermosetting adhesive of the connection portion are configured to be removed from the substrate, and the control unit adds the anisotropic conductive paste to the coating machine and the mounting machine as a new LED. Is transferred and the control is performed to mount the defective product on the location where the defective conduction product is removed. As an example, the continuity tester is configured to associate the presence or absence of lighting of the LED with the arrangement data of the LED and cause the storage unit to store the data to identify the position of the defective conduction product.

  According to this configuration, the work is conveyed to the heating zone by the first conveyor to rapidly melt the solder in the conductive particles of the anisotropic conductive paste, and subsequently, the work is conveyed to the cooling zone by the second conveyor. The solder in the conductive particles of the anisotropic conductive paste is quickly cured, and the work is passed through the first reflow furnace in less than the curing time of the thermosetting adhesive. Therefore, the work can be energized and can be reworked.

  According to the method for manufacturing a semiconductor device and the apparatus for manufacturing a semiconductor device of the present invention, a work can be energized and reworkable. Therefore, as an example, the yield in a semiconductor device that requires a high-density mounting technique, such as when mounting a large number of semiconductor chips having a width dimension on the order of 0.1 mm, on a substrate can be dramatically increased.

FIG. 1 is a configuration diagram schematically showing the inside of a first reflow furnace according to a semiconductor device manufacturing apparatus of an embodiment of the present invention. FIG. 2A is a diagram showing a state where the work is transferred to the first heating zone in the first reflow furnace of FIG. 1, and FIG. 2B is a state where the work is transferred to the second heating zone following the state of FIG. 2A. FIG. 2C is a diagram showing a state where the work is conveyed to the first cooling zone subsequent to the state of FIG. 2B. FIG. 3A is a diagram showing a state where the work is conveyed to the second cooling zone after the state of FIG. 2C, and FIG. 3B shows a state where the work is conveyed to the labyrinth on the outlet side after the state of FIG. 3A. FIG. 3C is a diagram showing a state in which the work is conveyed to the outlet subsequent to the state of FIG. 3B. FIG. 4 is a graph showing a temperature profile of a work in the first reflow furnace of FIG. FIG. 5 is a configuration diagram schematically showing a circuit configuration of the semiconductor device manufacturing apparatus of the present embodiment. FIG. 6A is a cross-sectional view schematically showing a work in which a semiconductor chip is mounted by coating an anisotropic conductive paste on a substrate, and FIG. 6B shows a state where FIG. 6A is followed by a first heat treatment for conduction. FIG. 6C is a cross-sectional view schematically showing the tested work, and FIG. 6C is a cross-sectional view schematically showing the work immediately after the defective product is removed following the state of FIG. 6B. FIG. 7A is a cross-sectional view schematically showing a work in which a new semiconductor chip is mounted at a location where a defective product has been removed after the state of FIG. 6C, and FIG. 7B shows the first heating after the state of FIG. 7A. FIG. 7C is a cross-sectional view that schematically shows the workpiece that has been subjected to the treatment and the continuity test, and FIG. 7C is a schematic diagram of the semiconductor device that has been subjected to the second heat treatment and inspected after the state of FIG. 7B. FIG. FIG. 8 is a flowchart showing the manufacturing procedure of the semiconductor device according to this embodiment. FIG. 9 is a flowchart showing another example of the manufacturing procedure of the semiconductor device according to this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a part or all of a semiconductor device manufacturing apparatus 1 (hereinafter, sometimes referred to as apparatus 1) of the present embodiment, and particularly, schematically shows the inside of a first reflow furnace 3. FIG. The left side in the figure is the inlet side (upstream side), and the right side in the figure is the outlet side (downstream side). The first reflow furnace 3 has a main body 30 in which a transfer mechanism and a heating mechanism are incorporated, and a controller 35. In the example of FIG. 1, a control unit 2 that controls various devices included in the manufacturing apparatus 1 is mounted on or adjacent to the first reflow furnace 3. The control unit 2 may include a controller 35. In all the drawings for explaining the embodiments, members having the same function are designated by the same reference numeral, and repeated description thereof may be omitted.

  The work 90 is an intermediate body before becoming the semiconductor device 94 in the manufacturing process, and as shown in FIGS. 6A to 7C, the first intermediate body 90a, the second intermediate body 90b, the third intermediate body 90c, and the fourth intermediate body. 90d and a fifth intermediate 90e. The work 90 has a substrate 93, a semiconductor chip 91, and an anisotropic conductive paste 92.

  A cross-sectional view schematically showing an example of the semiconductor device 94 is shown in FIG. 7C. The substrate 93 has a mounting surface on which a wiring pattern made of a conductor such as copper is formed on the upper surface 93a, and the electrode 93e is exposed. The semiconductor chip 91 has electrodes 91e formed on one end side and the other end side of a chip-shaped main body, and the lower surface 91b of the semiconductor chip 91 is mounted on the upper surface 93a of the substrate 93 so that the electrodes 91e and 93e are separated from each other. Soldered so that it can be energized. The semiconductor device 94 is a product in which a plurality of semiconductor chips 91 are flip-chip mounted on a substrate 93 and electrically connected and joined. For example, a large number of semiconductor chips 91 are mounted on the substrate 93 in a matrix. The semiconductor chip 91 is, for example, an LED, a transistor, an integrated circuit element, or another known chip-shaped semiconductor. The anisotropic conductive paste 92 has conductive particles 92a for solder-connecting the electrodes 91e and 93e, and a thermosetting adhesive 92b for bonding and fixing the semiconductor chip 91 and the substrate 93. .. In the anisotropic conductive paste 92, conductive particles 92a are dispersed in an uncured thermosetting adhesive 92b which is liquid or gel. As the thermosetting adhesive 92b, epoxy, polyimide, or other known thermosetting resin is applied. The conductive particles 92a include solder or a conductive metal forming the solder, and gold, silver, copper, tin, zinc, nickel, bismuth, indium, other known conductive metals, or alloys thereof are applied.

  FIG. 1 is a configuration diagram schematically showing the inside of the first reflow furnace 3. In the first reflow furnace 3, a loading conveyor 33, a first conveyor 31, a pressing roller 34, and a second conveyor 32 are arranged in this order from the upstream side. The main body 30 has an inlet 30a, a labyrinth 36a, a heating zone 3b, a cooling zone 3c, a labyrinth 36f, and an outlet 30f in this order from the upstream side. The loading conveyor 33 is arranged from the upstream side of the inlet 30a to the upstream side of the labyrinth 36a, and is configured to convey the work 90a (90) from the upstream side of the inlet 30a to the upstream side of the labyrinth 36a. The first conveyor 31 is arranged from the downstream side of the input conveyor 33 to the upstream side of the second conveyor 32, and allows the workpiece 90 transferred from the input conveyor 33 to pass through the labyrinth 36a on the inlet side to heat the heating zone 3b. It is configured to be transported to. The pressing roller 34 is a mechanism for maintaining the conveyance speed of the work 90 when the work 90 is transferred from the heating zone 3b to the cooling zone 3c. The second conveyor 32 is arranged from the downstream side of the first conveyor 31 to the downstream side of the outlet 30f, and allows the workpiece 90 transferred from the first conveyor 31 to pass through the cooling zone 3c and the labyrinth 36f on the outlet side. Through the outlet 30f and conveyed to the next step.

  That is, in the first reflow furnace 3, the first conveyor 31 is provided from the inlet side to the heating zone 3b, and subsequently, the second conveyor 32 is provided from the cooling zone 3c to the outlet side. As an example, there is a case where the first conveyor 31 is provided from the upstream side of the inlet 30a to the heating zone 3b, and the second conveyor 32 and the outlet side that pass the cooling zone 3c and the labyrinth 36f on the outlet side. There may be a case in which the labyrinth 36f passes through the exit 30f and is conveyed to the next process in a separate configuration.

  The first reflow furnace 3 is a device that heats the workpiece 90 in a non-contact manner while conveying the workpiece 90 in an atmosphere of an inert gas such as nitrogen. The first conveyor 31, the second conveyor 32, and the input conveyor 33 are made of metal chain rails such as titanium and titanium alloy that suppress thermal distortion. The heating zone 3b is arranged in the order of the first heating zone 3b1 and the second heating zone 3b2, and is a heater such as a hot air panel type heater having a uniform heat distribution. The cooling zone 3c is arranged in the order of the first cooling zone 3c1 and the second cooling zone 3c2, and is composed of a cooling mechanism such as a blower fan. The labyrinth 36a and the labyrinth 36f have a mechanism for suppressing the outflow of the inert gas to the outside of the machine while maintaining the temperature inside the furnace. Note that the labyrinth, the heater, and the cooling mechanism can apply known techniques such as the above-mentioned Patent Document 3.

  FIG. 5 is a configuration diagram schematically showing an example of a circuit configuration of the semiconductor device manufacturing apparatus 1. The device 1 includes, for example, a control unit 2, a first reflow furnace 3, a coating machine 4, a mounting machine 5, a continuity test machine 6, a defective product removing machine 7, and a second reflow furnace 8. In the example of FIG. 5, the control unit 2 is a computer, and the control program 27 operating on the computer is installed. A CPU 21 is built in the control unit 2. Then, the display device 24 and the display input means 23 such as a keyboard and a mouse are connected. Here, the display input means 23 may be a touch panel provided on the screen of the display device 24. The control unit 2 has a database 22 stored in a predetermined storage area of the secondary storage device. The database 22 can also be stored in an external storage device (tertiary storage device) such as a flash memory. The control unit 2 can be applied by partially changing the configuration of a known computer. The firmware of the control program 27 is, for example, configured in a language such as C language or assembler, and can be updated from a Web browser or a command line.

  In the example of FIG. 5, the first reflow furnace 3 has a main body 30 and a controller 35, the coating machine 4 has a main body 40 and a controller 45, the mounting machine 5 has a main body 50 and a controller 55, and a continuity tester. 6 has a main body 60 and a controller 65, the defective product removing machine 7 has a main body 70 and a controller 75, and the second reflow furnace 8 has a main body 80 and a controller 85. Then, the controller 25 and the controller 35 are signal-connected, the controller 25 and the controller 45 are signal-connected, the controller 25 and the controller 55 are signal-connected, the controller 25 and the controller 65 are signal-connected, and the controller 25 and the controller 75 is signal-connected, and the controller 25 and controller 85 are signal-connected. With this configuration, data can be transferred and controlled in real time. Examples of the signal connection method include wired LAN, wireless LAN, USB connection, and other known network connections.

  The applicator 4 is configured to apply the anisotropic conductive paste 92 to the substrate 93 by, for example, a dispenser method or a printing method. Further, as an example, the anisotropic conductive paste 92 is transferred to the semiconductor chip 91 by a transfer method. The mounting machine 5 is configured to mount the semiconductor chip 91 on the substrate 93 by a pick-and-place method, for example. As an example, the application machine 4 and the mounting machine 5 may be combined. The continuity tester 6 is, for example, configured to operate the semiconductor chip 91 by energization to make a pass / fail judgment. The defective product removing machine 7 has, for example, a configuration in which a non-contact heating mechanism and a suction or suction mechanism are combined, and when the defective conductive product is detected from the semiconductor chip 91, the defective defective product is removed. Is. As an example, the continuity tester 6 and the defective product remover 7 may be combined. The second reflow oven 8 is configured to heat the work 90 in a non-contact manner to thermoset the thermosetting adhesive 92b when a defective conduction product is not detected from the semiconductor chips 91. As an example, the second reflow furnace 8 may be a batch furnace.

  Next, the method for manufacturing the semiconductor device of this embodiment will be described below.

  8 and 9 are flowcharts showing an example of the manufacturing procedure of the semiconductor device 94 according to the present embodiment. In this embodiment, the mounting step S1 in which the plurality of semiconductor chips 91 are mounted on the substrate 93 via the anisotropic conductive paste 92 to form the first intermediate body 90a and the first intermediate body 90a is heat-treated to perform the second step. A first heat treatment step S2 for forming the intermediate body 90b, a continuity test step S3 for conducting a continuity test on the second intermediate body 90b, and a conduction failure product when a conduction failure product 911 is detected from the mounted semiconductor chips 91. A defective product removing step S4 in which the 911 is removed to form the third intermediate body 90c, and a new semiconductor chip 912 is mounted in place of the defective conductive product 911 on the substrate 93 where the defective conductive product 911 is removed, In the re-mounting step S5 for forming the intermediate body 90d and when the conduction failure product is not detected in the conduction test step S3, the work 90 is heated to thermoset the thermosetting adhesive 92b. A second heat treatment step S6 to.

  In the remounting step S5, as an example, the anisotropic conductive paste 92 is applied to a portion of the substrate 93 where the defective conduction product 911 is removed, and a new semiconductor chip 912 is mounted to form the fourth intermediate body 90d. In addition, as an example, the anisotropic conductive paste 92 is transferred to a new semiconductor chip 912, and the new semiconductor chip 912 is mounted on the substrate 93 at a location where the defective conduction product 911 is removed. It may be 90d.

  The number of defective product removing steps S4 and remounting steps S5 may vary depending on the type, number, arrangement, pitch, mounting density, processing conditions, and other conditions of the semiconductor chips 91 to be mounted. The example of FIG. 8 is a flow chart in the case where the defective product removing step S4 and the re-mounting step S5 are repeated once or more until no defective conductive product is detected. Further, the example of FIG. 9 is a flow chart when the defective product removing step S4 and the re-mounting step S5 are completed once. The defective product removing step S4 and the re-mounting step S5 may be performed once, twice, three times or four times or more. Considering the influence of the heat treatment on the product characteristics, the manufacturing time and the manufacturing cost, the defective product removing step S4 and the re-mounting step S5 are preferably less than 10 times, more preferably less than 5 times.

  2A to 3C are configuration diagrams schematically showing the inside of the first reflow furnace 3 that heats the work 90 while conveying the work 90. FIG. 4 is a graph showing an example of the temperature profile of the work 90 in the first reflow furnace 3. The vertical axis of the graph represents the surface temperature of the work 90, and the horizontal axis of the graph represents the transportation time of the work 90. In the present embodiment, the heating zone 3b in the first reflow furnace 3 is set to a temperature equal to or higher than the temperature at which the solder contained in the conductive particles of the anisotropic conductive paste 92 melts, and the material manufacturer of the anisotropic conductive paste 92 is set. The recommended heating temperature is set to less than 50 [° C]. The cooling zone 3c in the first reflow furnace 3 is set below the temperature at which the solder contained in the conductive particles of the anisotropic conductive paste 92 melts, and above room temperature. The control unit 2 carries the work 90 into the furnace, heats the work 90 in a predetermined heating curve in the first heating zone 3b1, and maintains the peak temperature in the second heating zone 3b2 for a predetermined time. In 3c1, the temperature is lowered according to a predetermined temperature-decreasing curve, in the second cooling zone 3c2, the temperature is gradually cooled, and in the next step, control is performed to bring it into a handleable state and carry it out.

  Next, the manufacturing procedure shown in FIG. 8 will be described below.

  The anisotropic conductive paste 92 has, for example, lead-free solder or conductive particles 92a having a conductive metal forming the lead-free solder, and a thermosetting adhesive 92b made of an epoxy resin.

  In the mounting step S1, the application machine 4 applies the anisotropic conductive paste 92 to the electrodes 93e of the substrate 93, and the mounting machine 5 causes the lower surfaces 91b of the plurality of semiconductor chips 91 to face the upper surface 93a of the substrate 93. And mount it on the substrate 93 to form a first intermediate body 90a as shown in FIG. 6A. Alternatively, in the mounting step S1, the anisotropic conductive paste 92 is transferred to the lower surface 91b of the semiconductor chip 91 by the coating machine 4, and the lower surfaces 91b of the plurality of semiconductor chips 91 are faced to the upper surface 93a of the substrate 93 by the mounting machine 5. Then, it is mounted on the substrate 93 to form a first intermediate body 90a as shown in FIG. 6A. The control unit 2 controls the operations of the coating machine 4 and the mounting machine 5.

  Subsequent to the mounting step S1, a first heat treatment step S2 heat-treats the first intermediate body 90a to form a second intermediate body 90b. In the first heat treatment step S2, as shown in FIGS. 2A and 2B, the loading conveyor 33 carries the first intermediate 90a into the inlet 30a by the control of the loading conveyor 33 by the control unit 2. Next, by the control of the feeding conveyor 33 and the first conveyor 31 of the control unit 2, the feeding conveyor 33 and the first conveyor 31 cooperate to transfer the first intermediate 90 a from the feeding conveyor 33 to the first conveyor 31. To do. Then, under the control of the first conveyor 31 by the controller 2, the first conveyor 31 conveys the first intermediate body 90a to the first heating zone 3b1 by pitch feed.

  Next, by the control of the first conveyor 31 by the control unit 2, the first conveyor 31 causes the first intermediate body 90a to stay in the first heating zone 3b1 for a predetermined time, and immediately thereafter, the second heating from the first heating zone 3b1. It is conveyed to the zone 3b2 by pitch feed. Subsequently, as shown in FIG. 2C, the control of the first conveyor 31 and the second conveyor 32 by the control unit 2 causes the first conveyor 31 and the second conveyor 32 to operate in cooperation with each other to heat the first intermediate body 90a. The first conveyor 31 is transferred from the first conveyor 31 to the second conveyor 32, and as shown in FIG. 3A, the second conveyor 32 keeps the first intermediate body 90a from a heated state at a constant conveying speed. To the first cooling zone 3c1 and then to the second cooling zone 3c2 at a constant transportation speed. Then, as shown in FIGS. 3B and 3C, the heated and cooled second intermediate body 90b is carried out from the outlet 30f.

  According to the present embodiment, the first intermediate body 90a is pitch-fed to the first heating zone 3b1 and allowed to stay for a predetermined time, thereby heating the first intermediate body 90a with a predetermined temperature rise curve with a uniform heat distribution, The peak temperature can be reached quickly. In addition, the first intermediate body 90a heated to the peak temperature is pitch-fed to the second heating zone 3b2 and retained for a predetermined time, so that the peak temperature in the first intermediate body 90a is maintained with a uniform heat distribution. The conductive particles 92a can be completely melted by heating the conductive particles 92a completely.

  The peak temperature of the heated first intermediate body 90a is set to a temperature higher than the melting temperature of the solder in the conductive particles 92a. As a guide, the peak temperature is set within the melting temperature of the solder in the conductive particles 92a plus 10 [° C.]. The peak temperature is preferably set within the melting temperature of the solder in the conductive particles 92a plus 5 [° C.]. This makes it possible to quickly melt the solder in the conductive particles 92a while minimizing the thermal damage to the semiconductor chip 91 in the first intermediate body 90a.

  The heating time for heating the first intermediate 90a in the first heating zone 3b1 until it reaches the peak temperature is 20 [seconds] to 40 [seconds] as a guide. Further, the heating time for continuously heating the first intermediate body 90a in the second heating zone 3b2 while maintaining the peak temperature thereof is 5 [seconds] to 30 [seconds] as a guide. This prevents failure due to thermal strain of the semiconductor chip 91 in the first intermediate body 90a and scattering of the anisotropic conductive paste 92, suppresses thermal curing of the thermosetting adhesive 92b as much as possible, and causes cohesiveness of the conductive particles 92a. It is possible to improve the temperature of the conductive particles 92a and quickly melt the solder in the conductive particles 92a.

  Here, the average value of the temperature rising curve of the first intermediate body 90a heated in the first heating zone 3b1 is, for example, 4 [° C / sec] to 8 [° C / sec]. The maximum value of the temperature rising curve is, for example, 4 [° C / sec] to 20 [° C / sec]. Considering the heat conduction loss, the hot air temperature in the first heating zone 3b1 is set to a temperature higher than the peak temperature of the first intermediate body 90a. As an example, the hot air temperature in the first heating zone 3b1 is set to a temperature higher than the peak temperature of the first intermediate body 90a by 20 [° C] to 100 [° C]. The hot air temperature in the second heating zone 3b2 is set to a temperature lower than the hot air temperature in the first heating zone 3b1 and is set to a temperature at which the peak temperature of the first intermediate body 90a can be maintained.

  That is, with the above-described configuration, the work 90 can be rapidly heated by the first heating zone 3b1 and the melting of the solder in the conductive particles 92a of the work 90 can be completed in a short time by the second heating zone 3b2. The thermosetting of the adhesive 92b can be suppressed as much as possible.

  Then, the work 90 is heated to the peak temperature, and the solder in the conductive particles 92a is completely melted and is transported to the first cooling zone 3c1 at a constant transport speed, and cooled by the cool air until the solder in the conductive particles 92a is hardened. .. The cooling time is 10 [seconds] to 30 [seconds] as a guide. Subsequently, the work 90 is conveyed to the second cooling zone 3c2 at a constant conveyance speed in a state where the solder in the conductive particles 92a is hardened, and is cooled by cool air to a temperature at which an electric conduction test can be performed and a temperature at which the work can be handled. The cooling time is 10 [seconds] to 40 [seconds] as a guide. The temperature at which the energization test is possible is 20 [° C] to 40 [° C] as a guide. With this configuration, it is possible to quickly start the energization test while suppressing the thermosetting of the thermosetting adhesive 92b on the work 90 as much as possible.

Here, the first reflow furnace 3 is placed on the upper surface 93e of the substrate 93 at a position between the first conveyor 31 and the second conveyor 32 when the work 90 is transferred from the first conveyor 31 to the second conveyor 32. A pressing roller 34 is provided in contact therewith . By providing the pressing roller 34, the work 90 can be quickly transported to the first cooling zone 3c1 while maintaining the transport speed of the first conveyor 31. As an example, the pressing roller 34 has a structure in which two rollers are rotatably supported by a shaft so as to be rotatable at a predetermined interval, and are in contact with the upper surface 93e of the substrate 93 near both sides of the mounting surface. Thus, the work 90 can be sent to the second conveyor 32 while suppressing the influence of the weight load and maintaining the conveyance speed of the first conveyor 31 while suppressing the substrate 93 in a parallel state.

  According to the present embodiment, the first reflow furnace 3 operates the work 90 by the linking operation of the first conveyor 31 and the second conveyor 32 in less than the curing time of the thermosetting adhesive 92b in the anisotropic conductive paste 92 thereof. Can be passed through. Further, in the first heat treatment step S2, the work 90 is conveyed to the heating zone 3b by pitch feeding to quickly melt the solder in the conductive particles 92a of the anisotropic conductive paste 92, and subsequently, the work 90 is cooled in the cooling zone 3c. Then, the solder in the conductive particles 92a of the anisotropic conductive paste 92 is hardened by being conveyed at a constant speed, so that the work 90 can be quickly brought into a state in which it can be energized and reworked.

  Following the first heat treatment step S2, the continuity test step S3 tests the continuity of the second intermediate body 90b by the continuity tester 6. The semiconductor chip 91 is an LED as an example. In the case of an LED, a non-defective product is lit and a defective product is not lit. Therefore, it is possible to easily determine whether the product is good or bad, and a received light signal from a light receiving means such as a CCD camera or an optical sensor is associated with the arrangement data of the semiconductor chip 91 to obtain data. The position of the defective product can be easily specified in combination with the storage means for storing. The semiconductor chip 91 may be a chip-shaped semiconductor to which the flip chip bonding technique is applied. Therefore, the semiconductor chip 91 may be an LED, a transistor, an integrated circuit element, or any other known semiconductor chip-shaped.

  In the continuity test step S3, as shown in FIG. 6B, when a defective continuity product 911 is detected from the mounted semiconductor chips 91, the defective product removal step S4 is performed, and the defective product remover 7 mounts the defective product. The defective conductive product 911 is removed from the semiconductor chip 91 to form the third intermediate body 90c. As an example, in the laser head 77, the laser F1 is passed through the substrate 93 to irradiate the lower surface side of the defective continuity product 911 to heat the mounting location of the defective continuity product 911 in a non-contact manner while the vacuum suction head is used. Is sucked in the direction of the arrow F2 to re-melt the solder in the thermosetting adhesive 92b and remove the defective conductive product 911 and the thermosetting adhesive 92b at the connection portion from the substrate 93. Subsequent to the defective product removing step S4, in the remounting step S5, the application machine 4 applies the anisotropic conductive paste 92 to the portion of the substrate 93 where the defective conductive product 911 is removed, and as shown in FIG. 7A. A new semiconductor chip 912 is mounted to form a fourth intermediate body 90d. Alternatively, in the re-mounting step S5, the anisotropic conductive paste 92 is transferred to a new semiconductor chip 912 by the coating machine 4, and as shown in FIG. 7A, the defective conductive portion 911 is removed from the substrate 93. A new semiconductor chip 912 is mounted to form a fourth intermediate body 90d.

  After the remounting step S5, the control unit 2 repeats the first heat treatment step S2 and the continuity test step S3 until no defective conduction is detected, and as shown in FIG. 7B, all the mounted semiconductor chips are mounted. 912 controls to make the fifth intermediate 90e which is a good conduction product.

  Then, when no defective continuity is detected in the continuity test step S3, the second heat treatment step S6 is performed, and the second reflow furnace 8 heats the fifth intermediate 90e to heat the thermosetting adhesive 92b. Let it harden. The hot air temperature in the second heat treatment step S6 is set to a temperature 2 [° C] to 5 [° C] higher than the thermosetting temperature of the thermosetting adhesive 92b in consideration of the loss of heat conduction for a predetermined time. To heat. As a guide, the heating time is 20 [minutes] to 240 [minutes]. As an example, the anisotropic conductive paste 90 is heated at the rated heating temperature for the rated heating time. When the heating time of the second heat treatment step S6 is 60 minutes or more as a guideline or when the aging treatment is included, the productivity can be improved by batch production in a batch furnace instead of the second reflow furnace 8. ..

  The manufacturing procedure shown in FIG. 8 is as described above. Here, if the types, the number, the arrangement, the pitch, the mounting density, the processing conditions, and other conditions of the semiconductor chips 91 to be mounted are prepared, the defective product removing step S4 and the remounting step S5 should be completed once. In this case, the productivity can be improved by adopting the manufacturing procedure shown in FIG.

  According to the present embodiment, since the work 90 can be energized and reworkable, as an example, a large number of LED chips having a width dimension of the order of 0.1 [mm], such as a backlight of an RGB display or LCD. The yield in a semiconductor device that requires a high-density mounting technique, such as when substrates are mounted in a matrix on a substrate, can be dramatically increased.

  In the above-described embodiment, the continuity tester 6 performs the continuity test on the work 90. However, the present invention is not limited to this. As long as the work 90 is in an energizable and reworkable state, it depends on the type of the semiconductor chip 91. It is possible to judge pass / fail. As the anisotropic conductive paste 92, a material composed of known conductive particles 92a and known thermosetting adhesive 92b can be applied, or a material of the binder to which a resin curing accelerator is not added is used. Good. The conductive particles 92a may contain lead depending on the application. The present invention is not limited to the above embodiment.

1 Semiconductor Device Manufacturing Apparatus 2 Control Section 3 First Reflow Furnace, 3b Heating Zone, 3b1 First Heating Zone, 3b2 Second Heating Zone, 3c Cooling Zone, 3c1 First Cooling Zone, 3c2 Second Cooling Zone 4 Coating Machine 5 Mounting machine 6 Continuity tester 7 Defective product remover 8 Second reflow furnace 30 Main body, 30a inlet, 30f outlet 31 First conveyor 32 Second conveyor 33 Input conveyor 34 Presser roller 35 Controller 36a, 36f Labyrinth 90 Work 90a First intermediate Body (work), 90b Second intermediate (work), 90c Third intermediate (work), 90d Fourth intermediate (work), 90e Fifth intermediate (work)
91 semiconductor chip, 91b lower surface, 91e electrode 92 anisotropic conductive paste, 92a conductive particles, 92b thermosetting adhesive 93 substrate, 93a upper surface, 93e electrode 94 semiconductor device 911 defective conduction product

Claims (10)

A mounting step of transferring an anisotropic conductive paste having conductive particles dispersed in an uncured thermosetting adhesive to a semiconductor chip and mounting the semiconductor chip on a substrate by a flip chip mounting technique,
A configuration having a first heat treatment step of heat-treating a workpiece in which a plurality of the semiconductor chip through the anisotropic conductive paste is mounted on the substrate by the first reflow furnace,
The first reflow furnace has a heating zone set at a melting temperature of the solder contained in the conductive particles or higher, a cooling zone set at a temperature lower than the melting temperature of the solder, and an inlet side to the heating zone. And a second conveyor provided over the outlet side from the cooling zone, and the first conveyor and the second conveyor provide the workpiece with the thermosetting adhesive. It is configured to pass through the first reflow furnace in less than a curing time,
The first heat treatment step, the workpiece mean the workpiece in the first heating zone by causing the transport to be retained by the heated first heating zone to the pitch feed of definitive to zone is 4 to 8 ° C. / sec Of the heating zone, and then, the work is conveyed to the second heating zone in the heating zone by pitch feed and retained therein to melt the solder, and subsequently, the work is conveyed to the cooling zone. Then, the solder is hardened so that the work can be energized and can be reworked. In the first heat treatment step, the work is heated in the first heating zone for 20 to 40 seconds until it reaches a peak temperature, and the work is maintained in the second heating zone at the peak temperature. Heating for 5 to 30 seconds and subsequently cooling the work in the cooling zone
The method for manufacturing a semiconductor device according to claim 1, wherein The semiconductor chip is an LED,
After the first heat treatment step, a continuity test step of conducting a continuity test on the workpiece, and a defective continuity product is detected by a defective product removing machine when a defective continuity product is detected from the LEDs in the continuity test step. There is a defective product removing step of removing the defective conductive product, and a remounting step of transferring the anisotropic conductive paste to a new LED instead of the defective conductive product and mounting the anisotropic conductive paste at a location where the defective conductive product is removed. Then
The defective product removing step reheats the solder by sucking with a vacuum suction head while heating the mounting location of the defective product without contact to re-melt the defective product and the thermosetting property of the connection portion. The method for manufacturing a semiconductor device according to claim 1 , wherein the adhesive is removed from the substrate . After the remounting step, the first heat treatment step and the continuity test step are repeated until the defective continuity product is no longer detected,
In the continuity test step, the position of the defective conduction product is specified by associating presence / absence of lighting of the LED with the arrangement data of the LED and storing the data by a storage unit. Of manufacturing a semiconductor device of. 5. The method according to claim 3, further comprising a second heat treatment step of heating the work to thermally cure the thermosetting adhesive when the conduction failure step is not detected in the conduction test step. Of manufacturing a semiconductor device of. A coating machine for transferring an anisotropic conductive paste having conductive particles dispersed in an uncured thermosetting adhesive to a semiconductor chip, and a mounting machine for mounting the semiconductor chip on a substrate by a flip chip mounting technique,
A configuration having a first reflow furnace and a control unit in which a plurality of the semiconductor chip through the anisotropic conductive paste is heated the onboard work on the substrate,
The first reflow furnace has a heating zone set to a temperature equal to or higher than the melting temperature of the solder contained in the conductive particles, a cooling zone set to a temperature lower than the melting temperature of the solder, and an inlet side to the heating zone. And a second conveyor provided over the outlet side from the cooling zone, and the first conveyor and the second conveyor provide the workpiece with the thermosetting adhesive. It is configured to pass through the first reflow furnace in less than a curing time,
At a position between the first conveyor and the second conveyor, a pressing roller that is in contact with the upper surface of the substrate when the work is transferred from the first conveyor to the second conveyor is provided,
Wherein the control unit, the average value of the work in the first heating zone be retained are transported by a pitch feed into the first heating zone definitive the workpiece to the heating zone 4 to 8 ° C. / sec Atsushi Nobori The solder is melted by heating in a curve and then conveying the work to the second heating zone in the heating zone by pitch feeding to make it stay , and subsequently, the work is conveyed to the cooling zone and An apparatus for manufacturing a semiconductor device, which is configured to cure solder so that the work can be energized and reworked. The pressing roller is configured such that the roller is rotatably supported by a shaft at a predetermined interval, and is in contact with a position avoiding the mounting surface of the substrate due to the weight of the roller.
The control unit heats the work in the first heating zone for 20 to 40 seconds until reaching the peak temperature, and 5 to 30 so that the work is maintained at the peak temperature in the second heating zone. Second heating, and then control to cool the work in the cooling zone.
7. The semiconductor device manufacturing apparatus according to claim 6. The semiconductor chip is an LED,
A continuity tester that conducts a continuity test on the work; and a defective product remover that removes the defective continuity product when a defective continuity product is detected from the LEDs by the continuity tester,
The defective product remover remelts the solder by sucking with a vacuum suction head while heating the mounting location of the defective product without contact, and the thermosetting property of the defective product and the connection portion. A structure for removing the adhesive from the substrate,
The control unit controls the coating machine and the mounting machine so that the anisotropic conductive paste is transferred to a new one of the LEDs and is mounted at a location where the defective conduction product is removed. 8. The apparatus for manufacturing a semiconductor device according to claim 6, wherein the manufacturing apparatus is a semiconductor device. The continuity tester is configured to associate the presence / absence of lighting of the LED with the arrangement data of the LED and store the data in a storage unit to specify the position of the defective continuity product.
9. The semiconductor device manufacturing apparatus according to claim 8. Claim 8 or characterized by having a second reflow furnace or a batch furnace to thermally cure the thermosetting adhesive by heating the workpiece when the conduction defective products was not detected by the continuity tester 9. A semiconductor device manufacturing apparatus according to item 9.

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