JP2012054268A - Heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating device having a structure not to produce uneven temperature in a substrate plane without use of a chamber structure, and capable of maintaining heat uniformity in a plane at low cost.SOLUTION: The heating device includes: a bottomed cylindrical-shaped cabinet 2; an air heater 3 for heating and temperature controlling inert gas etc., so as to introduce the inert gas etc. into the inner space of the cabinet; and a heat insulation material 4 coated on the outer circumference of the cabinet 2. Further, a nozzle plate 5 having a plurality of blow holes formed thereon closes an aperture portion opened on the cabinet 2. In a space between the inside of the cabinet 2 and the nozzle plate 5, there is fixed a flow speed resistive member 6 when gas introduced into the inner space of the cabinet 2 flows toward each blow hole. Further, a stage 9 for mounting and retaining a heating object such as a substrate 1 is disposed, facing opposite to the nozzle plate 5. In the heating device, the peripheral space of the heating object is open.

Description

  The present invention relates to a heating device for heating a semiconductor chip and a substrate, and more particularly to a heating device having a structure capable of efficiently heating a semiconductor and the entire substrate.

  With the development of technology in recent years, an apparatus for heating the entire glass substrate or semiconductor wafer as shown in Patent Document 1 has been put into practical use.

  In the manufacturing process of a semiconductor device, a plurality of semiconductor chips are mounted and fixed on a substrate such as glass epoxy or ceramic. In addition, when the substrate is divided into parts in which the semiconductor chip is mounted (hereinafter referred to as a chip mounting portion) in a matrix so that a large number of products can be obtained by dividing, a resin is placed in each chip mounting portion. Is applied, or solder is formed on the semiconductor chip connection wiring in each chip mounting portion. In this case, a plurality of semiconductor chips are simultaneously fixed on the substrate by mounting the semiconductor chip on the chip mounting portion of the substrate on which thermosetting resin or solder is provided in advance and heating the entire substrate. .

  In such a heating process, it is necessary to eliminate unevenness in the heating temperature over the entire substrate on which the semiconductor chip, which is a heating target, is placed. This is because making the chip bonding state constant for all semiconductor products obtained by dividing the substrate becomes a factor for increasing the product yield.

  Therefore, for example, in the conventional apparatus described in Patent Document 1, as shown in FIG. 4, the mounting table 43 in which the heater 41 is disposed and on which the semiconductor wafer 42 to be heated can be mounted is sealed. In order to prevent the uneven heating temperature of the substrate in the heating process as described above, the peripheral wall 45 of the sealed container 44 surrounds the entire periphery of the mounting table 43 through a space. It is configured. Further, the mounting table 43 is supported by a support 46 in the sealed container 44, and an exhaust pipe 47 for evacuating the sealed container 44 is connected to a wall of the sealed container 44 near the lower portion of the support 46. . That is, the heating device described in Patent Document 1 is configured so that the entire periphery of the heating object has a chamber structure.

JP 2004-006654 A

  However, the apparatus disclosed in Patent Document 1 has several problems.

  The first problem is that a structure (ie, a chamber structure) that covers the entire periphery of the object to be heated such as a semiconductor wafer or a substrate on which a semiconductor chip is mounted with a space (ie, a chamber structure) is employed. It is to become. This also causes a problem that the price becomes high in manufacturing the heating device.

  The second problem is that the heating efficiency is low. In the apparatus described in Patent Literature 1, a mounting table on which a heating target is placed is supported by a support column extending away from the inner bottom of the sealed container. For this reason, in the heating process described above, it is difficult to keep the gas ejection surface parallel to the heating object even if the heating gas is ejected from a plurality of holes formed in the gas ejection surface above the heating object. It is. Therefore, there is a possibility that the substrate to be heated cannot be heated uniformly in the in-plane direction.

  The third problem is that there is a limit to the size of the heating object that can be heated uniformly in the surface. Since the apparatus described in Patent Document 1 is configured to dispose a heating object in a sealed container and evacuate the inside of the sealed container with an exhaust pipe, a plurality of holes formed in the gas injection surface above the heating object. The flow rate at which the heated gas is ejected from is limited by the ability to exhaust from the exhaust pipe. For this reason, when a substrate or semiconductor wafer having a large heat capacity is heated uniformly in the surface, the size thereof is limited.

  Then, an object of this invention is to provide the heating apparatus which can solve the problem of the background art mentioned above. An example of the purpose relates to an apparatus for heating a semiconductor substrate, a substrate on which a semiconductor chip is mounted, etc., and there is no temperature unevenness in the substrate surface without using a chamber structure, and the heat in-plane uniformity can be maintained at a low cost. It is in providing the heating apparatus which has.

  One aspect of the present invention is a heating device for heating an object to be heated, a bottomed cylindrical casing, and gas introduction means for introducing gas into the inner space of the casing by heating and temperature control. And a heat insulating material coated on the outer periphery of the housing. Further, a nozzle plate in which a plurality of blowing holes is formed closes the opening that opens in the housing. In the space between the inner side of the casing and the nozzle plate, a flow velocity resistor is fixed when the gas introduced into the inner space of the casing flows toward each outlet hole of the nozzle plate. Furthermore, the stage which mounts and hold | maintains a heating target object is arrange | positioned facing the nozzle plate. And it is a heating apparatus with which the surrounding space of the heating target object is open | released.

  According to the present invention, when the heated gas is passed through the flow velocity resistor and is directed from the respective blowing holes of the nozzle plate to the object to be heated, the flow velocity and temperature of the gas from the respective blowing holes are made uniform by the flow velocity resistor. Therefore, it is possible to uniformly heat an object to be heated such as a substrate in the in-plane direction. In addition, since the heating device has an open space around the object to be heated, the device is small and can be easily and inexpensively adapted to maintenance and product shape changes. Furthermore, since the surrounding space of the heating object is open, the gas introduction flow rate is not limited, and the size of the heating object is not limited.

The sectional side view which shows the heating apparatus of this embodiment. The figure which plotted the blowing temperature result in the board | substrate surface by the heating apparatus of this embodiment. The figure which plotted the blowing temperature result when the flow velocity resistor was removed from the heating apparatus of this embodiment. FIG. 6 is a side sectional view showing a conventional device disclosed in Patent Document 1.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a side sectional view of a heating apparatus as an embodiment of the present invention.

  Referring to FIG. 1, the heating apparatus according to the present embodiment includes a support structure unit that supports the object to be heated, and a heat source unit that is disposed facing the object to be heated of the support structure unit and heats the object to be heated. Prepare. The object to be heated in this example is, for example, a substrate in which a portion on which a semiconductor chip is mounted (hereinafter referred to as a chip mounting portion) is arranged in a matrix so as to be divided into a plurality of semiconductor products. The substrate 1 has semiconductor chips mounted on a plurality of chip mounting portions via a thermosetting adhesive or solder.

  The heat source unit includes a bottomed cylindrical casing 2. Connected to the bottom of the housing 2 is an air heater 3 as an introduction pipe that introduces inert gas or compressed air (hereinafter abbreviated as heating gas) into the inside of the housing 2 while being heated by the heater. In the figure showing this example, the number of air heaters 3 is two, but the present invention is not limited thereto. The end of the tube constituting each air heater 3 on the side opposite to the housing 2 is connected to an inert gas source or a compressed air source (not shown). The air heater 3 includes a control device (not shown) that controls the heating temperature. The material of the housing 2 is preferably a material that is not easily deformed by heat.

  A heat insulating material 4 is provided on the outer periphery of the housing 2. Further, the opening of the housing 2 that opens toward the substrate 1 side of the object to be heated is closed by the nozzle plate 5. The nozzle plate 5 is provided with a plurality of blowout holes corresponding to chip mounting portions (that is, heating locations) arranged in a matrix on the substrate 1.

  A flow velocity resistor 6 is provided in the space between the inside of the housing 2 and the nozzle plate 5. Further, the flow velocity resistor 6 is sandwiched and fixed between the nozzle plate 5 and the rectifying mesh 7 in the inner space of the housing 1. The flow velocity resistor 6 is porous and has a plurality of holes having a diameter of about 0.5 μm to 3 mm (holes having an average diameter of about 1 μm) provided irregularly. In particular, the flow velocity resistor 6 has holes arranged irregularly, and the hole diameter, hole direction, and length are also made uneven. The flow velocity resistor 6 can be made of any metal or resin other than a porous body made of ceramic, aluminum nitride, or the like. For example, in the case of a flow velocity resistor using a resin material, the resin may be anything as long as it is heat resistant. The resin can be made porous by mixing and dissolving particles dissolved in an acid in the heat resistant resin. You can make a body.

  The heat source unit configured as described above is supported on the base 8 by a post (not shown). The support structure is installed on the base 8, and the space around the support structure is open. The support structure has a stage 9 that holds the substrate 1 in parallel with the gas blowing surface of the nozzle plate 5.

  According to the heating apparatus described above, the air heater 3 connected to an unillustrated inert gas source or compressed air source is introduced into the internal space of the housing 2. Since the outer wall of the housing 2 is covered with the heat insulating material 4, the once heated inert gas or compressed air enters the flow velocity resistor 6 through the rectifying mesh 7 without cooling in the internal space of the housing 2. .

  Since the flow velocity resistor 6 is a porous body having irregularly arranged and nonuniform pores, the heated gas that has entered the flow velocity resistor 6 is diffused uniformly throughout the porous body. The heated gas that has passed through the flow velocity resistor 6 is blown out from the blowout holes of the nozzle plate 5 and collides with the substrate 1. At this time, the heating gas temperature distribution in the in-plane direction of the substrate 1 becomes uniform.

  That is, even when the heated gas temperature distribution in the housing 2 is not uniform when the heated gas is caused to flow into the housing 2 by the air heater 3, the heated gas is diffused by the flow velocity resistor 6 and the substrate 1 can be heated without temperature unevenness. This can be seen well by comparing FIG. 2 and FIG. 2 shows a plot of the temperature distribution of the heated gas to the substrate 1 that is the heating object of the heating apparatus according to the present embodiment, and FIG. 3 shows the flow velocity resistor 6 removed from the heating apparatus of the present embodiment. The figure which plotted the heating gas temperature distribution to the board | substrate 1 measured using the thing is shown. Therefore, according to the present invention, the chip bonding state can be made constant for all semiconductor products obtained by dividing the substrate 1, and the product yield is improved.

  Further, the present invention does not employ a structure (that is, a chamber structure) that covers the entire periphery of the heating object with a space therebetween, and the surrounding space of the heating object is open. Therefore, it is possible to easily and inexpensively cope with maintenance and product shape change. Further, no structure other than the substrate holding mechanism such as the stage 9 is provided below the substrate 1 to be heated. Therefore, the effect that an apparatus can be designed small is also acquired. In addition, by changing the height of the stage 9, the nozzle plate 5 and the substrate 1 can be installed close to each other, and the heating gas can be efficiently blown onto the chip mounting portion on the substrate 1.

  Moreover, according to this invention, there is no restriction | limiting in the magnitude | size of a heating target object. That is, the present invention can be applied to a heating process in manufacturing a large semiconductor device or a thin semiconductor device. This is because the heating temperature of the object to be heated can be increased by arbitrarily increasing the number of air heaters 3 flowing into the housing 2 and increasing the inflow amount. This is because a temperature gradient can be created.

  In addition, as an application example of the present invention, the present invention can be used for any heating device other than a heating device and a bonding device for manufacturing a semiconductor device.

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Housing | casing 3 Air heater 4 Heat insulating material 5 Nozzle plate 6 Flow velocity resistor 7 Rectification mesh 8 Base 9 Stage

Claims (5)

A heating device for heating an object to be heated,
A bottomed cylindrical casing;
Gas introduction means for introducing gas into the inner space of the housing by heating and controlling the temperature;
A heat insulating material coated on the outer periphery of the housing;
A nozzle plate in which a plurality of blowing holes are formed and closing an opening opened in the housing;
A flow velocity resistor that is fixed in a space between the inside of the casing and the nozzle plate, and the gas introduced into the inner space of the casing flows toward each outlet hole of the nozzle plate;
A stage arranged to face the nozzle plate and holding the heating object thereon, and
A heating device in which a space around the heating object is opened. The heating device according to claim 1, wherein the flow velocity resistor is formed of a porous body that is irregularly arranged and has holes having nonuniform diameters, directions, and lengths. The heating apparatus according to claim 2, wherein a material of the flow velocity resistor is ceramic, aluminum nitride, metal, or resin. The heating object is a substrate in which chip mounting portions on which semiconductor chips are mounted are arranged in a matrix and partitioned so that a plurality of products can be obtained by being divided, and the plurality of chip mounting portions are thermosetting. The heating apparatus according to any one of claims 1 to 3, wherein the heating apparatus is a substrate on which a semiconductor chip is mounted via an adhesive or solder. 5. The heating apparatus according to claim 4, wherein each of the blowout holes of the nozzle plate is arranged corresponding to a chip mounting portion of the substrate arranged in a matrix.

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