JP2006196696A - Heater unit and heating method in heater unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heater unit in an underfill device enabling an efficient heating without limiting an object to be heated and a heating method for an underfill material. <P>SOLUTION: In an underfill treatment, a work W placed in a heating zone HZ formed of a heating cover 21, a fixed rail 51, a movable rail 52, a heater box 23, and a heating-zone room-temperature protective sheet 64 is irradiated with heat rays from a heater tube 31 for near infrared rays adjusted by an interference parting plate 32 while being rocked by a rocking mechanism 80. When the work W is heated for a fixed time, the inside of the heating zone HZ is equalized by an air blower 25. Consequently, the work W is heated efficiently and uniformly in a noncontact with a heater, and the heating zone is filled ideally with the underfill material. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heater unit that heats a target to be heated, which is stacked and supplied with an adhesive by a dispenser in the gap, so that the adhesive flows, and a heating method thereof.

  In recent years, due to the demand for miniaturization and thinning of electronic devices, when mounting a semiconductor chip or the like on a substrate, the lower surface is mounted on the substrate with a solder ball or the like, for example, a BGA (Ball Grid Array) type semiconductor chip without pins. In addition to fixing, it may be electrically connected together. In such a type, the semiconductor chip can be brought into a state of being in close contact with the substrate, and the thickness thereof can be reduced. In addition, since the number of contacts with the outside can be arranged in a plane on the flip side, many contacts can be concentrated and the chip can be greatly reduced. However, since the temperature of the chip rises due to high-speed arithmetic processing, and stress concentrates on the joint, there may be a case where the connection of the connected solder balls becomes defective. On the other hand, dust, gas, liquid, or the like may enter the joint and cause deterioration or short-circuiting of the connection portion. Therefore, underfilling is performed in which the gap is filled with an adhesive or the like (underfilling material).

  As the underfilling method, for example, Patent Document 1 discloses a method for underfilling an electronic assembly including a semiconductor die mounted on a substrate. This method heats these assemblies and the underfill dispenser, and the underfilling material flows into the space between the die and the opposing surface of the substrate through capillaries through specially provided “openings” in the assembly. To help. This underfilling material is generally made of a high-viscosity epoxy or the like, and is heated to have a low viscosity and a high fluidity, and is cured by being maintained at a high temperature. In the method described in Patent Document 1, the substrate and the underfilling material are heated by the heater to assist the capillary flow into the space of the underfilling material. Although it is widely known that many of these underfilling materials are reduced in viscosity by heating, in practice, specific temperature control at this time is important, and the optimum method is not necessarily clear. This temperature control has a great influence on the fluidity of the underfilling material. However, Patent Document 1 describes a technique for assisting the capillary flow of the underfilling material into the space by heating the substrate and the underfilling material using a heater. There is no disclosure about this method.

On the other hand, what is conventionally known as such a heater is that a sheathed heater is embedded in aluminum or ceramics, and the substrate is heated by the above-described sheathed heater through an aluminum block for contact according to the size of the substrate. Things were known. This method is characterized in that the heat of the sheathed heater is diffused by the aluminum block for contact and the amount of heat is accumulated, so that the substrate can be stably heated in a uniform state.
JP 2001-53090 A

  However, since it is necessary to replace the aluminum block for contact each time the substrate size changes, there is a problem that a large number of aluminum blocks for contact must be prepared according to the type of the substrate.

Further, when the substrate is changed, it is necessary to replace the aluminum block for the contact prepared in advance with this substrate, and there is a problem that the operability of the line is lowered.
Further, when the aluminum block for contact is replaced, it is necessary to raise the temperature of the aluminum block for contact to a predetermined temperature in order to restart the apparatus. Usually, this temperature increase requires a time of about 20 to 40 minutes, and further, there is a problem that the operability of the line is remarkably lowered.

  And because it is heated by making contact with the aluminum block for contact, when parts are mounted on both sides, such as a double-sided board, it cannot be in close contact with the aluminum block for contact, and efficient heating is not possible, or no heating at all Sometimes it was not possible.

  In view of the above problems, the present invention is to provide a heater unit and a heating method capable of efficiently heating an underfill material in underfilling without limiting the heating target such as the type of substrate. . In addition, a heater unit and a heating method capable of more optimized temperature management are provided.

  In order to solve the above-described problem, in the heater unit according to claim 1, the heater is heated to a predetermined temperature by using a heater to flow the adhesive against a heating target that is stacked and the adhesive is supplied to the gap by a dispenser. In the heater unit for heating in such a manner, the gist is that the heater is constituted by a radiation type heater that is not in contact with the heating target.

  In this invention, there exists an effect that the heating object like a double-sided board | substrate can also be processed by using a non-contact radiation type heater. Further, there is no need for an aluminum block for contact, and it is not necessary to prepare or preheat these blocks, so that the heating time can be shortened and the operating rate of the apparatus is improved.

  In the heater unit according to claim 2, in the heater unit according to claim 1, the heater is constituted by a linear tubular heater, and a plurality of the heaters are arranged in parallel, and an irradiation range of each heater is set. The gist is that an irradiation range limiting member for limiting each is provided.

  In this invention, in addition to the effect of the heater unit according to claim 1, since the irradiation range of the plurality of heaters can be limited, the control of heating is facilitated, and the entire substrate can be heated uniformly. .

  In the heater unit according to claim 3, in the heater unit according to claim 1 or 2, diffusion of heat generated by the heater is suppressed, and at least a part of the atmosphere to be heated is held. The gist is that an atmosphere holding means for forming a heating zone is provided.

  In this invention, in addition to the effect of the heater unit according to the first or second aspect, since the atmosphere to be heated can be held as the heating zone, there is an effect that stable heating can be performed.

According to a fourth aspect of the present invention, in the heater unit according to the third aspect, the heating zone is characterized in that the heating target itself maintains an atmosphere.
In the present invention, in addition to the effect of the heater unit according to the third aspect, since the heating zone can be formed by the heating target itself, the configuration can be facilitated, and the heating zone can be formed even if it is not covered with a separate member in the dispensing process There is an effect that can be done.

  According to a fifth aspect of the present invention, in the heater unit according to the third aspect, the heating zone surrounds the heating target by a member different from the heating target.

  According to the present invention, in addition to the effect of the heater unit according to the third aspect, since the entire heating object can be held by the dedicated member in the heating zone, the heating object can be effectively heated.

  In the heater unit according to claim 6, in the heater unit according to any one of claims 1 to 5, a transport conveyor capable of transporting the heating position of the heating target to a position facing the heater is provided. The summary is provided.

  In this invention, in addition to the effect of the heater unit according to any one of claims 1 to 5, the heating position of the heating target is transported to a position facing the heater by including such a transporting conveyor. And effective processing becomes possible.

  The heater unit according to claim 7, wherein, in the heater unit according to claim 6, the transport conveyor supports and transports both ends in a width direction that is a direction orthogonal to the transport direction of the heating target. And at least one support means that can move in the width direction according to the size of the object to be heated, and can be adjusted in the width direction corresponding to the object to be heated. And

According to the present invention, in addition to the effect of the heater unit according to the sixth aspect, there is an effect that it is possible to easily cope with a heating object having a different size and to enable efficient processing.
In the heater unit according to claim 8, in the heater unit according to claim 7, only the heater at a position facing the heating target placed on the transport conveyor is caused to generate heat in accordance with the adjustment in the width direction of the transport conveyor. This is the gist.

  According to the present invention, in addition to the effect of the heater unit according to the seventh aspect, only the heater corresponding to the object to be heated generates heat, so that there is an effect that unnecessary energy is not consumed and unnecessary portions of the apparatus are not overheated.

  The heater unit according to claim 9, wherein the heater unit according to claim 8 is a shield that covers a position where the heating target does not exist and prevents diffusion of heat of the heater in adjusting the width direction of the transfer conveyor. The gist is that a shielding means including a member is provided.

In this invention, in addition to the effect of the heater unit according to the eighth aspect, there is an effect that the atmosphere to be heated can be effectively maintained.
In the heater unit according to claim 10, in the heater unit according to claim 9, the shielding member is formed of a flexible sheet-like shielding sheet having one end connected to the outside of the supporting means of the conveyor. The gist of the invention is that it includes a shielding sheet winding means configured to wind up and store the shielding sheet.

In this invention, in addition to the effect of the heater unit according to the ninth aspect, there is an effect that the shielding member can be configured compactly.
The heater unit according to claim 11 is the heater unit according to any one of claims 6 to 10, wherein the heating object is supported by the conveyor via a holding plate on which the heating object is placed. The gist is to hold it in the means.

  In this invention, in addition to the effect of the heater unit according to any one of claims 6 to 10, the heating object can be placed on the transport conveyor via the holding plate provided separately from the transport conveyor. In the present invention, for example, when a chip is mounted on a substrate, a mode in which the substrate is directly transferred by a transfer conveyor is representative, but for example, a chip is transferred as it is by a transfer conveyor. Small heating objects that cannot be considered are also possible. Therefore, even for a small heating target that cannot be directly placed on the transfer conveyor, for example, the heating target is placed on a holding plate made of a metal plate having relatively good heat conductivity, and is heated on the holding plate. Thus, there is an effect that a large number can be easily heat-treated.

  In the heater unit according to claim 12, in the heater unit according to any one of claims 3 to 11, the heater unit includes a diffusion fan that makes the temperature unevenness of the atmosphere to be heated uniform by stirring. This is the gist.

  According to the present invention, in addition to the effect of the heater unit according to any one of claims 3 to 11, there is an effect that temperature unevenness during heating caused by the radiation type heater can be effectively uniformed.

  In the heater unit according to claim 13, in the heater unit according to any one of claims 1 to 12, when the temperature of the heating target or the atmosphere of the heating target is equal to or higher than a predetermined temperature, The gist is that a cooling blow for introducing unheated air into the atmosphere to be heated is provided.

  In this invention, in addition to the effect of the heater unit according to any one of claims 1 to 12, there is an effect that overheating of the heating target can be prevented quickly and the heating target can be effectively protected.

  The heater unit according to claim 14 is the heater unit according to any one of claims 1 to 13, wherein the heater is reciprocated in a width direction to move a position relative to the heating target. The gist is that a swing mechanism is further provided.

According to the present invention, in addition to the effect of the heater unit according to any one of claims 1 to 13, there is an effect that heating unevenness can be reduced and heating can be performed uniformly.
The heater unit according to claim 15 is the heater unit according to any one of claims 1 to 14, further comprising heating zone room temperature measuring means for measuring the temperature of the atmosphere to be heated. And

  In this invention, in addition to the effect of the heater unit according to any one of claims 1 to 14, there is an effect that optimum heating can be performed by directly measuring the temperature of the atmosphere to be heated.

  The heater unit according to claim 16 is characterized in that the heater unit according to any one of claims 1 to 15 is provided with a radiation thermometer for measuring a surface temperature of the heating target.

  According to the present invention, in addition to the effect of the heater unit according to any one of claims 1 to 15, there is an effect that optimum heating can be performed by directly measuring a heating target.

  In the heater unit according to claim 17, in the heater unit according to any one of claims 6 to 16, the transport conveyor includes a heat sink for radiating heat outside the atmosphere to be heated. Is the gist.

In this invention, in addition to the effect of the heater unit according to any one of claims 6 to 16, there is an effect of suppressing the overheating of the conveyor and enabling continuous operation.
The heater unit according to claim 18, wherein the heater unit according to any one of claims 1 to 17 is composed of a near-infrared heater having a wavelength of 760 nm to 2000 nm. To do.

  According to the present invention, in addition to the effect of the heater unit according to any one of claims 1 to 17, there is an effect that the heater starts up quickly and more appropriate temperature control is possible.

  In the heating method in the heater unit according to claim 19, a heater is used to flow the adhesive while maintaining the atmosphere with respect to the heating target that is laminated and the adhesive is supplied to the gap by the dispenser. A heating method in a heater unit for heating to a predetermined temperature, wherein an initial temperature setting step for setting a space that is an atmosphere of a heating target before carrying in the heating target to a predetermined initial temperature; When the initial temperature is reached, the step of carrying in the heating object, the step of supplying the adhesive to the heating object carried in, and the state of maintaining the atmosphere of the heating object A heating step of heating the object to be heated with a contact radiation type heater, and after the temperature has risen to a predetermined temperature, the heating is stopped, the atmosphere is stirred, and the temperature unevenness of the object to be heated And summarized in that comprising the steps of homogenization to equalize.

In this invention, there exists an effect that the optimal heating method can be provided in what is called underfilling.
The heating method for a heater unit according to claim 20, wherein, in the heating method for the heater unit according to claim 19, in the step of setting the initial temperature, if the temperature is lower than a predetermined initial temperature, the step of heating by the heater is performed. When the temperature is higher than a predetermined initial temperature, the gist is to execute a cooling step of introducing cool air to lower the temperature.

  In the present invention, in addition to the effect of the heating method in the heater unit according to claim 19, the temperature of the atmosphere at the start of heating is set to a predetermined temperature, so that the temperature unevenness of the heating target can be suppressed and preferable heating can be performed. There is an effect that can be done.

  The heating method for a heater unit according to claim 21, wherein the heating method for the heater unit according to claim 19 or 20, wherein the heating target is heated to a predetermined temperature before the carrying-in step. The main point is that

  In this invention, in addition to the effect of the heating method in the heater unit according to claim 19 or claim 20, there is an effect that preferable heating can be performed by setting the heating target to a predetermined temperature in advance.

  23. The heating method for a heater unit according to claim 22, wherein the heating step is performed by setting a temperature of the object to be heated to a radiation thermometer. The gist is that heating is performed by PID control based on the measurement result while measuring at 1.

  According to the present invention, in addition to the effect of the heating method in the heater unit according to any one of claims 19 to 21, by performing PID control, overheating due to overshoot and hunting are prevented and optimal heating is performed. There is an effect that can be done.

  According to the present invention, in the heating of the underfill material in underfilling, the heating target such as the type of the substrate is not limited, and efficient heating can be performed.

(First embodiment)
Hereinafter, an embodiment of underfilling by a dispensing apparatus 1 including a heater unit 2 embodying the present invention will be described with reference to FIGS.

  FIG. 1 is a perspective view showing a heater unit 2 in the dispensing apparatus 1 of the present embodiment. FIG. 2 is a plan view of the heater unit 2. 1 is defined as the conveyance direction of the workpiece W. In FIG. 2, the right direction is the transport direction. In addition, in FIGS. 1 and 2, a gantry robot, a measuring instrument, and a control device that move while supporting the dispense pump D, except for the dispense pump D in the dispense device 1 indicated by a two-dot chain line, which is not directly related to the present invention. Illustrations of the operation panel, power supply, etc. are omitted. Further, the heater unit for performing the dispense heat and the after heat other than the heater unit 2 for performing the preheating is also omitted in the drawing. Further, in order to show the inside of the heater unit 2, the work W and the heat cover 21 (see FIG. 3) are not shown.

The heater unit 2 is provided on the surface plate 11 of the dispensing apparatus 1 installed at an arbitrary installation location. The surface plate 11 is installed at an installation location by legs (not shown) and is fixed horizontally. The platen 11 is provided with a heater 30 supported by the swing mechanism 80. Further, a conveyor 50 that conveys the workpiece W (see FIG. 3) is disposed so as to surround the heater 30. A workpiece W such as a substrate conveyed from the outside of the dispensing apparatus 1 by a handling apparatus such as a robot is moved by the conveyor 50 in the order of the preheat zone, the dispense heat zone, and the afterheat zone. Since the heater units provided in each of these zones have substantially the same configuration as the heater unit 2 in the preheat zone described here, the heater units provided in the dispense heat zone and the afterheat zone will be described later. Only the differences will be explained.
(Heater 30)
The heater 30 is provided with a heat source for heating the workpiece W. As shown in FIG. 2, a plurality of heater tubes 31 a to 31 e (five in this embodiment) are provided in a box-shaped heater box 23 in parallel with each other in the conveyance direction at an approximately equal interval, and are arranged between them. The interference partition plate 32 is disposed.

FIG. 3 is a view of the heater unit 2 as viewed from the upstream side in the transport direction. Also in FIG. 3, a part of the dispensing apparatus 1 is omitted as in FIGS.
(Swing mechanism 80)
First, the swing mechanism 80 that swings the heater 30 will be described. Above the surface plate 11, there is provided a slide rail 13 disposed in the left-right direction of the heater 30 in a direction (width direction) orthogonal to the conveying direction, and a slider 14 that slides in the width direction is slidably disposed here. (See FIG. 1). A plate-like heater base 15 is placed on the slider 14. On the lower surface of the heater base 15, an arm 17 extends downward from a slit 16 formed in the surface plate 11. The slit 16 is formed so as not to interfere when the arm 17 moves in the width direction. A hole drilled in the transport direction is formed at the lower end of the arm 17, and a crank rod 18 that is rotatable along a circle perpendicular to the transport direction is connected. Further, the other end of the crank rod 18 is connected to the drive wheel 20 so as to be rotatable. The drive wheel 20 is rotated at a predetermined speed (for example, 2 seconds / rotation) by a motor (not shown). Therefore, as the drive wheel 20 rotates, the arm 17 is reciprocated in the horizontal direction via the crank rod 18. That is, the rotation of the drive wheel 20 causes the heater base 15 to swing in the width direction along the surface plate 11 with the slide rail 13 and the slider 14 in sliding contact with each other.

The heater base 15 supports a heater 30 via a spacer 19 provided on the left and right and a pair of elongated plate-like mounting plates 22 placed parallel to the conveying direction.
(Heater tube 31)
Next, the heater tube 31 serving as a heat source will be described. As shown in FIG. 2, a heater box 23 is provided on the heater base 15. The heater box 23 is a box-shaped member that is formed in a substantially rectangular parallelepiped with a long conveying direction and a relatively low height, and has a hollow interior and an open top.

  In the heater box 23, heater tubes 31 formed of a plurality of (for example, five) linear tubular heaters are arranged in parallel along the transport direction. The heater tube 31 is a heater that radiates near-infrared (760 to 2000 nm, here 1000 nm) heat rays. Therefore, the workpiece W can be heated in a non-contact manner. This near-infrared heater is configured, for example, as a halogen heater, and generates heat almost instantaneously (for example, within 1 second) by enclosing a halogen gas in a cylindrical tube made of quartz glass and applying a voltage to a tungsten filament. . In addition, the energy efficiency is high, and the temperature can be raised to about 1200 (° C.) at about 2000 W. Further, spot heating can be easily performed. Therefore, it has a feature that control for heating the workpiece W can be easily performed.

  These heater tubes 31a to 31e are turned on / off by a drive circuit for each one by a control device, or voltage control and PWM (Pulse Width Modulation) control are performed under PID (Proportional / Integral / Differential) control. . The control device includes a known computer including a CPU, a RAM, and a ROM, and executes a heating method of the present invention by executing a known temperature control program.

  As an example of the control, first, in conjunction with the width of the workpiece W, for example, control can be performed such that only the heater tubes 31c to 31e facing the workpiece W are turned on and the other heater tubes 31a to 31b are turned off. . Even when all the five heater tubes 31a to 31e are turned on, an arbitrary ratio, for example, 31a and 31e at both ends are set to 100% output, and the three heater tubes 31b to 31d are set to output 60%. To do. Then, output control is performed by PID control while maintaining this output balance. When the width of the workpiece W is narrow and only three are lit, the two are automatically switched so that the two at both ends are set to 100% output and the center is set to 60% output. In this case, the output balance can be set in advance by performing test heating. Further, when the part to be heated is biased to one end of the workpiece W, it is possible to perform a manual operation so that only the heater pipe 31e on the end side is set to 100% output and the other heater pipes 31a to 31d are set to 0%. Of course.

  As shown in FIG. 1, an interference partition plate 32 is disposed on the heater box 23. The interference partition plate 32 includes a plurality of partition plates 32a to 32f. The interference partition plate 32 is formed by bending a metal (for example, stainless steel) thin plate, and the length of each partition plate 32 a to 32 f is the same as the length of the heater box 23 in the longitudinal direction. Further, as shown in FIG. 3, each of the partition plates 32a to 32f connects the vertical wall portion formed so as to provide an opening above each of the heater tubes 31a to 31e and the vertical portion. It is comprised from the horizontal part which covers the upper part of the heater box 23. FIG. Therefore, the partition plates 32a to 32f are formed in a gate shape in the cross-sectional shape in the width direction. The interference partition plate 32 formed and arranged in this way irradiates the workpiece W with heat only in a specific region without being affected by the adjacent heater tube 31. Therefore, the lower surface of the workpiece W is irradiated with heat only from any one heater tube 31 in all regions. Therefore, control can be performed with one heater pipe in accordance with the temperature at an arbitrary position of the workpiece W.

(Fan 25)
As shown in FIGS. 2 and 3, openings 24 (for example, two) are provided on the bottom surface of the heater box 23, and the fan 25 is disposed here. As shown in FIG. 3, the fan 25 is an axial fan, for example, and causes air to flow from the opening 24 into the heater box 23. Further, a diffuser 26 is provided above the fan 25 in the downstream direction of the air flow, the air flow from the fan 25 is diffused, and the temperature unevenness in the heating zone HZ is agitated and made uniform.

(Conveyor 50)
Next, the conveyor 50 will be described. As shown in FIG. 1, a fixed rail 51 and a moving rail 52 are provided in parallel along the transport direction so as to sandwich the heater 30. These are supported at a position higher than the heater 30 by support legs 12a, 12b, 12c, and 12d (see FIG. 3) disposed on the surface plate 11. In FIG. 1, the conveyor 50 is extended so that the workpiece | work W can be conveyed to the preheat zone and the dispense heat zone. The fixed rail 51 and the movable rail 52 are formed of rectangular metal pipes (for example, shaped steel) having a rectangular cross section. In FIG. 1, a plurality (six) of pulleys 53 are arranged on the surface on the heater 30 side, and a rubber endless belt 54 is hooked and tensioned to the belt 54 by a tensioner 55. . Then, according to the rotation of the pulley 53 driven by the conveyor transport motor 56, the belts 54 on both sides are synchronized, and the workpiece W placed on the circulating endless belt 54 moves. Note that the workpiece W is basically a rectangular object, and both end portions thereof are placed on the belts 54 positioned in parallel to each other.

  As shown in FIG. 2, the rotating shaft 59 rotated by the conveyor width adjusting motor 60 is connected to the conveyor moving screws 57 and 58 via bevel gears, and further transmits the rotation to the conveyor moving screws 57 and 58. . The conveyor moving screws 57 and 58 are screwed into nuts (not shown) provided on the support legs 12 b and 12 d of the moving rail 52, and the moving rail 52 is supported by the rotation of the conveyor moving screws 57 and 58. The legs 12b and 12d (see FIG. 3) move in the width direction. Therefore, by rotating the conveyor width adjusting motor 60 by the control device 90 (see FIG. 4), the interval between the fixed rail 51 and the moving rail 52 of the conveyor 50 is adjusted according to the size of the workpiece W as the moving means of the conveyor 50. it can.

  Next, a support structure for the heat cover 21 will be described. As shown in FIG. 3, the heat cover 21 is disposed so as to cover the workpiece W. First, one end of the heat cover 21 is supported on the upper portion of the fixed rail 51 on the right side in the transport direction, and the left side is supported by a heat cover support portion 61 erected from the surface plate 11. The heat cover 21 is formed of a heat insulating material such as a foam material having a high heat insulating property in order to prevent the heat of the heater 30 from diffusing. At this time, the lower part of the heater tube 31 is surrounded by the heater box 23 so that heat is difficult to escape. Moreover, since the lower portion of the fixed rail 51 on the right side in the transport direction is formed in a wall shape and is close to the heater box 23, the release of heat from this is also reduced. Further, the moving rail 52 arranged on the left side prevents diffusion of heat from the upper part of the heater 30 like the fixed rail. Therefore, the heater box 23, the fixed rail 51, the moving rail 52, and the heat cover 21 form a generally closed space that prevents the heat of the heater 30 from diffusing, and the heat of the heater 30 is retained. This space is referred to as a heating zone HZ in this embodiment, and is an example of the atmosphere holding means of the present invention.

  The workpiece W shown in FIG. 3 is substantially the same as the width of the heater box 23, and there is no large opening in the heating zone HZ. In this state, no large opening is formed above the workpiece W.

  By the way, the moving rail 52 and the support leg 12d shown by the two-point difference line are positions when the work W having a small width is supported. At this time, since the moving rail 52 moves greatly to the right side in the drawing, a large opening that continues from above the workpiece W is formed on the left side of the moving rail 52. If it does so, the temperature fall above the workpiece | work W will be caused especially. Therefore, in the present embodiment, a heating zone room temperature protection sheet 64 that covers an opening formed on the back side (left side) from the upper end of the moving rail 52 is disposed. The heating zone room temperature protective sheet 64 is formed of a flexible and airtight material, for example, a thin plate of SUS (stainless steel). Further, since the size of the opening changes due to the movement of the moving rail 52, a winding roll 62 that winds the heating zone room temperature protection sheet 64 is disposed on the heat cover support 61. The take-up roll 62 is always urged by a spring 63 in a direction in which the heating zone room temperature protection sheet 64 is taken up. Therefore, when the moving rail 52 is at the position indicated by the solid line in FIG. 3, the heating zone room temperature protection sheet 64 is almost wound on the winding roll 62. On the other hand, when the moving rail 52 is at the position indicated by the two-dot chain line, the heating zone room temperature protection sheet 64 is pulled out largely, covers the opening formed on the back surface of the moving rail 52, and suppresses the heat diffusion of the heater 30. It is configured as follows.

  In the heating zone HZ formed in this way, a heating zone room temperature measuring thermocouple 65 that measures the temperature of air that becomes the atmosphere of the workpiece W on the lower surface of the workpiece W is arranged. This heating zone room temperature measuring thermocouple 65 is an example of a heating zone room temperature measuring means. Further, a radiation thermometer 66 for measuring the surface temperature of the upper surface of the work W is disposed.

  On the other hand, a cooling blow 67 for blowing high-pressure air supplied from the outside onto the upper surface of the workpiece W is arranged. The cooling blow 67 cools the workpiece W by blowing high-pressure air when the workpiece W is heated. Of course, it is also used to set the initial temperature of heating.

  As shown in FIGS. 1 and 3, a heat sink 68 is formed outside the heating zone HZ of the fixed rail 51 and the moving rail 52. For this reason, even if the fixed rail 51 and the moving rail 52 are heated from the inside, they are prevented from overheating by radiating heat from the heat sink 68.

  Next, the control of the dispensing apparatus 1 will be described with reference to the block diagram of the control configuration in the dispensing apparatus 1 of the present embodiment shown in FIG. A controller 90 is provided in the dispensing device. The control device 90 is a known computer having a CPU, a RAM, and a ROM, and a program for controlling the dispensing device 1 is stored in a storage medium such as a ROM or HDD (Hard Disk Drive) and executed. A control panel 91 having input / output means such as a keyboard, a display, and a button is connected to the control device 90 via an interface and operated.

  The conveyor 50 is provided with a conveyor position sensor 93, which detects the position in the width direction of the moving rail 52 of the conveyor 50 by an encoder (not shown) and inputs the encoder pulse (detection signal) to the control device 90. .

  Further, a workpiece position sensor 92 is disposed on the conveyor 50, the position of the workpiece W conveyed by the conveyor 50 is detected by an optical sensor (not shown), and the detection signal is input to the control device 90.

Furthermore, the control device 90 inputs a signal from a radiation thermometer 66 (see FIG. 3) that detects the surface temperature of the upper side of the workpiece W placed on the conveyor 50 by communication.
And the signal from the heating zone room temperature measurement thermocouple 65 (refer FIG. 3) which measures the room temperature of the heating zone HZ which is the atmosphere of the workpiece | work W is AD-converted, and is input by communication.

  On the other hand, the control device 90 sends a control signal to each drive means 94 by executing a control program via the interface, and controls a control solenoid valve (not shown) of the cooling blow 67, heater tubes 31a to 31e, and a swing mechanism. Control is performed by sending drive signals to 80 drive motors (not shown), the conveyor transport motor 56, and the conveyor width adjustment motor 60.

  (Heating Method for Dispensing Device) A heating method for the dispensing device 1 configured as described above will be described. FIG. 5 is a flowchart showing the entire procedure of the heating method of the dispensing apparatus 1. The heating method of the dispensing apparatus 1 includes a setting process (S1), a preheating process (S2), a dispensing heat process (S3), and an afterheating process (S4).

  The workpiece W exemplified in the present embodiment is one in which a BGA type semiconductor chip C is placed on the upper surface of the substrate B, and mounting by soldering is completed in a reflow furnace. And here, as preheating before underfilling, before supplying an underfill material, for example, an epoxy-based thermosetting adhesive between the substrate B as the workpiece W and the semiconductor chip C, the workpiece W is preliminarily heated. Here, the lower surface of the workpiece W is directly heated by the heater tubes 31a to 31e as shown in FIG. For this reason, even if the surface temperature of the lower surface of the workpiece W is measured, the internal temperature cannot be accurately known. For this reason, the radiation thermometer 66 measures the surface temperature of the upper surface of the workpiece W to monitor how much the inside of the workpiece W is heated.

  In the setting step (S1), prior to the heating of the workpiece W, the size of the workpiece W, the heating temperature of the underfill material, the heating time, the output balance of the heater tube 31 and the like are transferred from the control panel 91 to the control device 90. This is an input process. Here, the dispensing apparatus 1 is controlled by a control program stored in the control apparatus 90 in accordance with the input data. At this time, the control device 90 automatically moves the moving rail 52 of the conveyor 50 in accordance with the input width of the workpiece W, and prepares the workpiece W to be conveyed by the conveyor 50.

  When the setting procedure is completed, the process proceeds to the preheating step (S2). Here, FIG. 6 is a flowchart showing the procedure of the preheating process. In the preheating step (S2), first, the temperature of the heating zone HZ in the preheating area is measured by the heating zone room temperature measuring thermocouple 65, and it is determined whether or not the temperature is within a predetermined temperature range (S11). As a result, when the temperature is outside the predetermined temperature range (S12; NO), an entrance stopper (not shown) as a blocking member is protruded at the conveyor entrance so that the workpiece W cannot be automatically and manually inserted from the upstream device (S13). ). Note that this entrance stopper is an example, and other methods such as a door and a shutter may be used as long as the worker cannot carry the workpiece W into the preheat area.

  Next, it is determined whether or not the detected temperature is lower than a predetermined range (S14). If the determination is lower than the predetermined temperature (S14; YES), the heater 30 heats the heating zone HZ (S15). If the determination exceeds the predetermined temperature range (S14; NO), the cooling blow 67 cools by air blow (S16). In this way, heating or cooling is performed, and the temperature determination (S11) is performed again. In this case, when the temperature is not within the predetermined temperature range (S12; NO), the steps S13 to S16 are repeated.

  In this way, when the temperature of the heating zone HZ falls within the predetermined temperature range (S12; YES), the entrance stopper is released (S17). Note that this step is ignored if the entrance stopper has already been released. Then, the workpiece W is carried in and conveyed to a predetermined position (S18). When the workpiece W is detected by the workpiece position sensor 92, the control device 90 starts temperature holding control (S19) by the heater 30.

  In the temperature holding control (S19), the temperature of the workpiece W is monitored by the control device 90 by the radiation thermometer 66. Based on the detected temperature and the set target temperature Tt, the control device 90 reduces the difference while PWM controlling the output to the heater tube 31 by PID control. When the difference between the average temperature and the target temperature Tt is large, the heater tube 31 outputs 100% of the maximum output. At this time, the average temperature approaches the target temperature Tt, and the output is gradually reduced from 100% by PID control.

  Here, the control device 90 stirs the atmosphere of the heating zone HZ with the fan 25 and averages the temperature unevenness of the workpiece W. Specifically, during the temperature holding control by the heater tube 31, if the output of the heater tube 31 is higher than a certain reference (for example, 40% or more of the maximum output), the fan 25 is stopped because the stirring effect of the fan 25 is relatively small. Keep it done. On the other hand, when the average temperature approaches the target temperature Tt and the output of the heater tube 31 is lower than a certain reference (for example, less than 40% of the maximum output), the air in the heating zone HZ is also sufficiently warmed. The temperature unevenness of the workpiece W is averaged by stirring the atmosphere of the zone HZ. At the same time, the heater tube 31 repeats ON / OFF with a relatively small output.

  Here, FIG. 7 is a graph showing a result of an experiment on how the temperature unevenness of the workpiece W is changed by the fan 25 during the temperature holding control (S19). In this experiment, a radiation thermometer that measures three different temperatures 66a, 66b, and 66c on the workpiece W was installed, and the temperature change during temperature holding control was observed. This graph shows the passage of time on the X axis and the temperature on the Y axis. As shown in this graph, at the beginning of heating, these temperatures 66a, 66b, 66c are different from each other. However, by rotating the fan 25 and stirring the atmosphere in the heating zone HZ, the temperature 66a, 66b and 66c converge to the target temperature Tt in such a manner that the amplitudes W1 and W2 of the temperature changes up and down are gradually reduced. Therefore, since the temperature unevenness due to heating is eliminated by the rotation of the fan 25 during the temperature holding control, the radiation thermometer 66 is not inconvenient even if it is controlled by temperature measurement at one representative place.

  In this way, the temperature is determined by the radiation thermometer 66, and when the temperature is not within the set temperature (S20; NO), the work W is not transferred to the dispensing process, and the temperature holding control (S19) is continued.

  When the average temperature Ta reaches the target temperature Tt and the heater temperature is once lowered and then the temperature is lowered, the PID control is performed again, and when the output of the heater tube 31 becomes 40% or more of the maximum output, the fan 25 The rotation is stopped.

  In this way, when the temperature of the workpiece W falls within the set temperature (S20; YES), it is determined whether the workpiece W can be transported to the dispense heat area (S21). If the workpiece W cannot be transported to the dispense heat area because there is still another workpiece W (S21; NO), the temperature holding control (S19) is continuously executed to move the workpiece W to the dispensing process at any time. Manage temperature so that you can. In addition, when the workpiece W in the dispense heat area can be transferred to the dispensing process, for example (S21; YES), the workpiece W preheated to an appropriate temperature is immediately conveyed to the dispense heat area (S22).

  The dispense heat process (S3), which is the next process, will be described. In the dispense heat process, the workpiece W that has been preheated is conveyed to the dispense heat zone. The structure of the heater unit in the dispense heat zone is basically the same as that of the heater unit 2 in the preheat zone. However, since the underfill material is supplied by the dispense pump D, the upper portion is opened without the heat cover 21. Further, since the upper part is opened, there is no heating zone room temperature measurement thermocouple 65, and only the temperature Tw of the workpiece W is measured by the radiation thermometer 66. Hereinafter, the same configuration is referred to by the same reference numeral as the heater unit in the preheat zone.

  In the dispensing heat process, the atmosphere is agitated by the fan 25 while the conveyed work W is heated by the heater 30. At the same time, a gantry robot (not shown) precisely moves the dispense pump D to a predetermined position on the workpiece W by image recognition (average error is about several μm), and supplies a necessary amount of underfill material. The supplied underfill material is sufficiently preheated and has a predetermined viscosity or less, and this is a semiconductor chip mounted on the substrate B of the workpiece W that has become a predetermined temperature or higher (for example, 70 ° C.) by preheating. Supply from one end of C to the gap. Then, the underfill material having a predetermined viscosity is filled in the gap by capillary action.

  During this time, the temperature of the workpiece W is kept constant. In this way, when the supply of the underfill material is completed, it is conveyed to the heater unit in the after heat zone by the conveyor 50, and the after heat process (S4) is performed.

  The heater unit in the after heat zone used in the after heat step (S4) is the same as the heater unit 2 in the preheat zone. However, since the purpose is to fill every corner of the underfill material at a constant temperature, it goes without saying that the processing time differs in the heat treatment.

  In the after heat zone, temperature determination is performed in the same manner as in the preheat zone. When the heating zone HZ is not within the predetermined temperature range, heating or cooling processing is performed. In this case, in the preheating process (S2), the entrance of the preheat zone is blocked by a stopper at the entrance of the preheating zone, but the entrance stopper of the preheating zone is also activated in the afterheating process. In this case, the workpiece W may already be carried into the preheater zone and the dispense heater zone. In this case, even if the heating zone HZ is determined to be out of the predetermined temperature range in the temperature determination in the after heat zone, the next process is executed as it is. This is because heating is already started, and it is considered that there is less damage when the work is continued than when the work is stopped halfway. Of course, if the heating zone HZ is determined to be outside the predetermined temperature range in the temperature determination in the after heat zone, the operation may be stopped immediately.

The work W supplied and filled with the underfill material as described above is separately subjected to a process of being maintained at a predetermined temperature for a predetermined time for thermosetting.
In the heater unit and the heating method of the above embodiment, the following effects can be obtained.

  (1) In the above embodiment, since the radiation type heater 30 that is not in contact with the workpiece W is used, there is an effect that it can be widely heated, such as those that cannot be heated by a contact heater such as a double-sided substrate. . Furthermore, since the relative position of the workpiece W and the heater tube 31 is moved by the swing mechanism 80, there is an effect that the heating is made uniform.

(2) Since a near-infrared heater is used for the heater tube 31, the rise in heating is fast, and there is an effect that more accurate and accurate temperature control can be performed.
(3) Furthermore, the heater 30 can be irradiated with a wide range by a plurality of heater tubes 31. Since the interference partition plate 32 is provided, there is an effect that the influence of the heater tube 31 adjacent to the workpiece W can be removed and heat irradiation without unevenness can be performed. Therefore, there is an effect that temperature control can be easily performed.

  (4) Further, a space in which the heater tube 31 is substantially closed is formed by the heat cover 21, the fixed rail 51, the moving rail 52, and the heater box 23, and this is used as a heating zone HZ to generate heat generated from the heater tube 31. Can be kept valid. Therefore, there is an effect that the workpiece W can be efficiently heated.

(5) Further, the conveyor 50 has an effect that the moving rail 52 can be adjusted in the width direction, and substrates having different sizes can be placed and transported as they are.
(6) When the moving rail 52 is moved, the opening formed on the back surface of the moving rail 52 is shielded by the heating zone room temperature protection sheet 64 and effectively suppresses the diffusion of heat in the heating zone HZ. There is an effect that can be. The heating zone room temperature protection sheet 64 is formed of a flexible thin plate made of SUS and is wound and stored when not in use, so that there is an effect that it can be configured compactly.

  (7) When the moving rail 52 is moved, the unnecessary heater tube 31 is turned off according to the movement of the moving rail 52. Therefore, there is an effect that unnecessary power consumption and overheating can be suppressed.

  (8) Further, the fan 25 can stir the heat unevenness in the heating zone HZ to make it uniform, so that uniform heating of the workpiece W can be realized. In particular, there is an effect that heating can be performed from both sides, which is not possible with a contact heater.

  (9) If the workpiece W is likely to overheat, there is an effect that the workpiece W temperature can be immediately lowered and heated safely by blowing the compressed air directly from the cooling blow 67 onto the workpiece W.

  (10) Since the sensor includes a heating zone room temperature measurement thermocouple 65 and a radiation thermometer 66 and is controlled by PWM under PID control by a computer, optimal and precise control can be performed.

(11) Even when operated for a long time, since the fixed rail 51 and the moving rail 52 are provided with the heat sink 68, there is an effect that overheating can be effectively suppressed.
(12) Under such circumstances, the underfill material has an effect that it flows in the gap between the workpieces W and is ideally filled by capillary action. Even when a BGA type semiconductor chip is mounted on a double-sided board, there is an effect that it is extremely efficient and that a safe and accurate operation can be easily performed.

In addition, you may change the said embodiment as follows.
As an example of heating, a semiconductor chip stacked on a substrate has been described as an example. However, the present invention can also be applied to a semiconductor chip stacked and mounted on a semiconductor chip.

  In such a case, for a small work W that cannot be placed directly on the conveyor 50, a fixed rail 51, which is a support means, and a moving rail 52 are used instead of a substrate, such as an aluminum plate, instead of a holding plate with good heat conduction. By placing the workpiece W through the holding plate, there is an effect that heating similar to that of a conventional contact heater can be performed. Even in that case, since the heating zone HZ is formed, efficient heating can be performed.

  In the present embodiment, preheating, dispensing heat, and afterheating in underfilling have been described, but the heater unit of the present invention is not limited to these. For example, even when a relatively heavy object such as a coil is fixed on a substrate with a thermosetting adhesive, it can be suitably implemented.

  The heater tube is not limited to a near infrared heater using a halogen heater, and it goes without saying that various heaters such as a medium to far infrared heater, a ceramic heater, etc., such as its wavelength, configuration, and output are used depending on the object.

In addition, although the work W after the reflow has been described here, the work W is used for temporary fixing before the reflow or bonding of parts without reflow.
○ Adhesives are not limited to underfill materials, and various adhesives are used. Moreover, not only a thermosetting adhesive but a thermoplastic adhesive can be used.

(Circle) the flowchart which shows the procedure of a heating method is an example of this invention, and this invention is not limited to this procedure.
Note that it goes without saying that the present invention can be modified and improved by those skilled in the art without departing from the scope of the claims.

The perspective view of the heater unit 2 in the dispensing apparatus 1 of this embodiment. The top view of the heater unit 2 in the dispensing apparatus 1 of this embodiment. The figure which looked at the heater unit 2 in the dispensing apparatus 1 of this embodiment from the conveyance direction upstream. The block diagram of the structure of the control in the dispensing apparatus 1 of this embodiment. The flowchart which shows the procedure of the heating method in the dispensing apparatus 1 of this embodiment. The flowchart which shows the procedure of the heating in a preheating process. The graph which shows the state by which the temperature nonuniformity of the workpiece | work W in the temperature holding control (S19) in a preheating process is eliminated by the fan 25.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Dispensing apparatus, 2 ... Heater unit, 21 ... Thermal cover, 25 ... Fan, 30 ... Heater, 31 (ae) ... Heater pipe, 32 ... Interference partition plate, 50 ... Conveyor, 51 ... Fixed rail, 52 ... Moving rail, 62 ... take-up reel, 64 ... heating zone room temperature protective sheet, 65 ... heating zone room temperature measuring thermocouple, 66 ... radiation thermometer, 67 ... cooling blow, 68 ... heat sink, 80 ... swing mechanism, 90 ... control Device, HZ ... heating zone, W ... work, Thz, Tw ... temperature, Tt ..., target temperature.

Claims (22)

In a heater unit that is laminated and heated to a predetermined temperature with a heater to flow the adhesive against a heating target to which the adhesive is supplied by a dispenser in the gap,
A heater unit, wherein the heater is a radiation type heater that is not in contact with the object to be heated. The said heater is comprised from the linear tubular heater, The said heater was arranged in parallel, and the irradiation range limitation member which each limits the irradiation range of each heater was provided. Heater unit. 3. An atmosphere holding unit that suppresses diffusion of heat generated by the heater and forms a heating zone that holds at least a part of the atmosphere to be heated is provided. The heater unit described. The heater unit according to claim 3, wherein the heating target itself maintains an atmosphere in the heating zone. The heater unit according to claim 3, wherein the heating zone surrounds the heating target by a member different from the heating target. The heater unit according to any one of claims 1 to 5, further comprising a transfer conveyor that can transfer the heating position of the heating target to a position facing the heater. The transport conveyor is configured to support a pair of support means for transporting while supporting both ends in the width direction, which is a direction orthogonal to the transport direction of the heating target, and at least one support means in the width direction according to the size of the heating target. The heater unit according to claim 6, further comprising: a moving unit that is movable, and capable of adjusting in a width direction corresponding to the heating object. The heater unit according to claim 7, wherein only the heater at a position facing the heating target placed on the transport conveyor is caused to generate heat in accordance with the adjustment in the width direction of the transport conveyor. The heater according to claim 8, further comprising a shielding unit that includes a shielding member that covers a position where the heating target does not exist and prevents diffusion of heat of the heater in adjusting the width direction of the conveyor. unit. The shielding member comprises a flexible sheet-like shielding sheet having one end connected to the outside of the support means of the transport conveyor, and includes shielding sheet winding means capable of winding and storing the shielding sheet. The heater unit according to claim 9. The heater unit according to any one of claims 6 to 10, wherein the heating object is held on a support means of the transport conveyor via a holding plate on which the heating object is placed. The heater unit according to any one of claims 3 to 11, further comprising a diffusion fan that makes the temperature unevenness of the atmosphere to be heated uniform by stirring. The apparatus according to claim 1, further comprising a cooling blow that introduces unheated air into the atmosphere to be heated when the temperature of the atmosphere to be heated or the atmosphere to be heated reaches a predetermined temperature or higher. The heater unit according to any one of 12 above. The heater unit according to any one of claims 1 to 13, further comprising a swing mechanism that reciprocally moves the heater in a width direction to move a position relative to the heating target. . The heater unit according to any one of claims 1 to 14, further comprising heating zone room temperature measuring means for measuring the temperature of the atmosphere to be heated. The heater unit according to any one of claims 1 to 15, further comprising a radiation thermometer that measures a surface temperature of the heating target. The heater unit according to any one of claims 6 to 16, wherein the transport conveyor includes a heat sink for radiating heat outside the atmosphere to be heated. The heater unit according to any one of claims 1 to 17, wherein the heater includes a near-infrared heater having a wavelength of 760 nm to 2000 nm. A heating method in a heater unit that heats a target to be heated, which is laminated and supplied with an adhesive by a dispenser to the gap, while maintaining the atmosphere so that the adhesive flows. Because
An initial temperature setting step for setting a space that is an atmosphere of the heating target before carrying in the heating target to a predetermined initial temperature;
A step of carrying in a heating target when the space reaches a predetermined initial temperature;
An adhesive supply step for supplying an adhesive to the heating target carried in;
A heating step of heating the heating object with a non-contact radiation heater in a state where the atmosphere of the heating object is maintained;
A heating method in a heater unit, comprising: a heating step in which heating is stopped after the temperature is raised to a predetermined temperature, and the atmosphere is stirred to make temperature unevenness of the heating target uniform. In the initial temperature setting step, if the temperature is lower than a predetermined initial temperature, a heating step of heating with a heater is performed,
The heating method for a heater unit according to claim 19, wherein when the temperature is higher than a predetermined initial temperature, a cooling step of introducing cold air to lower the temperature is executed. The heating method for a heater unit according to claim 19 or 20, further comprising a preheating step of heating the heating target to a predetermined temperature before the carrying-in step. The heating step performs heating by PID control based on the measurement result while measuring the temperature of the heating target with a radiation thermometer. Heating method in the heater unit.

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