JP2010003857A - Hot press device and method of manufacturing electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate the generation of a nonconformity such as the damage of a circuit part embedded in a semirigid sheet-shaped thermosetting resin and an electrical defective connection between the circuit parts or the like. <P>SOLUTION: The viscous state of the thermosetting resin is detected by measuring the travel speed and acceleration of a press board 10a or the temperature or the like of an object in case of a hot press. The generation of the nonconformity such as the damage of the circuit part embedded in the thermosetting resin during the hot press and the electrical defective connection between the circuit parts or the like by detecting the boosting timing of a pressing pressure from the viscous state in case of the hot press. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat press apparatus used for production of an electronic device such as a circuit component built-in substrate and a flip chip mounting body, and a method of manufacturing an electronic device using the same.

  As electronic devices have become smaller, thinner, and more sophisticated in recent years, there has been an increasing demand for higher density mounting of circuit components mounted on printed circuit boards and higher performance of circuit boards mounted with circuit components. It is getting stronger. In view of such a demand, technology development of flip chip mounting in which a circuit component built-in substrate in which circuit components are embedded in a substrate and a bare IC are directly mounted on the circuit substrate has been actively performed. Among these, the electronic device is made while the circuit components are embedded in a semi-cured sheet-like thermosetting resin whose viscosity has been reduced by heating and pressure treatment, and then the resin is cured and electrically connected. There is a technique including a process of forming a structure.

First, an example of a circuit component built-in substrate which is an electronic device including the above-described steps and a method for manufacturing the same will be described with reference to FIG.
FIG. 5 is a process cross-sectional view illustrating a method for manufacturing a circuit component built-in substrate.

  In FIG. 5, reference numeral 100 denotes a circuit component built-in substrate. 101 is a composition in which a thermosetting resin (epoxy resin) and an inorganic filler (silica filler) are mixed, and is a composite sheet which is a semi-cured sheet-like curable resin. Reference numeral 102 denotes a conductive via paste which is a composition in which metal conductive particles are mixed in a thermosetting resin, and 103a and 103b denote printed wiring boards. Reference numeral 104 denotes a chip component mounted on the printed wiring board 103a, which is embedded between the printed wiring boards 103a and 103b with a composite sheet. A method of manufacturing the circuit component built-in substrate 100 configured as described above will be briefly described below.

<Manufacturing process>
(Step a) A through hole is formed at a predetermined position of the composite sheet 101.
(Step b) The via paste 102 made of a conductive resin is filled in the above-described through holes.
(Step c) The chip component 104 is mounted on the printed wiring board 103a in advance. The printed wiring board 103a, the composite sheet 101, and the printed wiring board 103b are sequentially stacked in alignment with a position where the conductive via paste 102 is connected to a predetermined wiring pattern on the printed wiring boards 103a and 103b positioned above and below. At that time, the chip component 104 mounted on the printed wiring board 103a is arranged inside.
(Process d) Heating / pressurizing treatment is performed by a hot press apparatus, the chip component 104 is embedded in the composite sheet 101, and the conductive via paste 102 is sufficiently pressed against a predetermined wiring electrode, and then the composite sheet 101 is formed. The circuit component built-in substrate structure is formed while curing and electrical connection is performed, and the circuit component built-in substrate 100 is manufactured (for example, see Patent Document 1).

Next, an example of a flip chip mounting body including the above-described steps and a manufacturing method thereof will be shown.
FIG. 6 is a process diagram showing the manufacture of the flip chip mounting body.

  In FIG. 6, 200 is a flip chip mounting body, 201 is a bare IC chip, and 202 is a stud bump. Reference numeral 203 denotes a printed wiring board, and 204 denotes a sealing adhesive film which is a semi-cured sheet-like thermosetting resin. A method for manufacturing the flip chip mounting body 200 configured as described above will be briefly described below.

<Manufacturing process>
(Step a) A stud bump 202 is formed on a predetermined pad on the bare IC chip 201 using an Au wire.
(Process b) The sealing adhesive film 204 is affixed on the bear IC chip 201 mounting surface of the printed wiring board substrate 203.
(Step c) The bare IC chip 201 is reversed, and the stud bump 202 is aligned and mounted at a position where the stud bump 202 abuts on a predetermined wiring electrode on the printed wiring board 203.
(Process d) Heating / pressurizing treatment is performed by a heat press apparatus so that the bare IC chip 201 is embedded in the sealing adhesive film 204, and the stud bump 202 formed on the bare IC chip 201 is connected to a predetermined wiring of the printed wiring board 203. The sealing adhesive film 204 is cured after being sufficiently pressed against the electrode, and the flip chip mounting structure is formed while electrical connection is made, so that the flip chip mounting body 200 is manufactured (for example, Patent Document 2). reference).
Japanese Patent Laid-Open No. 11-220262 JP 2002-261449 A

  In the circuit component built-in substrate 100 and the flip chip mounting body 200 described above, a composite sheet in which circuit components such as the chip component 104 or the bare IC chip 201 are reduced in viscosity by heating and pressurizing processes using a hot press apparatus. After being embedded in a semi-cured sheet-like thermosetting resin such as 101 or the sealing adhesive film 204, an electronic device structure is formed while making electrical connections. The hot press apparatus used at this time is provided with a mechanism for controlling the temperature, pressure, or pushing amount (= the amount by which the structure to be hot pressed is crushed) to a predetermined value. Furthermore, there is also an apparatus in which the heating amount and the pressurizing amount can be set to be a predetermined value as time passes.

A diagram showing the melt viscosity characteristics of the semi-cured sheet-like thermosetting resin used in these is shown in FIG.
In FIG. 7, the horizontal axis represents the elapsed time under a certain temperature environment, and the vertical axis represents the melt viscosity. The semi-cured sheet-like thermosetting resin has a characteristic that the viscosity is once lowered by heating, and then the curing reaction is started and the hardness is increased by further heating.

  Therefore, when using a conventional heat press device, in the process of embedding circuit components in a semi-cured sheet-shaped thermosetting resin, the sheet-shaped thermosetting type is sufficient to prevent damage to the circuit components. In anticipation of the decrease in the viscosity of the resin, control was performed so that a large press pressure was applied after a certain period of time had elapsed. However, when the viscosity has not decreased sufficiently due to fluctuations in the shape of the structure (size and thickness), fluctuations in resin characteristics, changes in ambient temperature, or air flow, or when the viscosity has increased due to hardening. There was a problem in that pressure was applied and the circuit components to be embedded were damaged.

  Furthermore, in the case where a large pressure is transferred at the stage where the curing of the thermosetting resin has progressed too much, it becomes impossible to sufficiently press against the predetermined wiring electrode connecting the conductive via paste 102 and the stud bump 202. In some cases, poor electrical connection occurred.

  The present invention has been made in view of the above points, and its main object is to manufacture a circuit component embedded in a semi-cured sheet-like thermosetting resin with respect to a method of manufacturing a circuit component built-in substrate or a flip chip mounting body. An object of the present invention is to provide a heat press apparatus that can eliminate the occurrence of problems such as breakage and poor electrical connection between circuit components, and a method for manufacturing an electronic device using the same.

  In order to achieve the above-mentioned object, the heat press apparatus of the present invention is configured to heat and press the semi-cured sheet-shaped thermosetting by providing a semi-cured sheet-shaped thermosetting resin between a plurality of circuit components. A heat press mechanism comprising a pair of heat press plates for curing the mold resin to form an electronic device structure and heating and pressurizing the plurality of circuit components provided with the semi-cured sheet-like thermosetting resin; A detection mechanism for detecting the viscosity state of the semi-cured sheet-like thermosetting resin, and a control mechanism for generating a control signal for the hot press mechanism from the detected viscosity state, and the heat signal is generated by the control signal. The press mechanism is controlled.

Further, the control of the hot press mechanism is to increase the pressing force of the hot press mechanism.
Further, the moving speed of the hot press plate is detected as the viscosity state.

Further, the moving acceleration of the hot press plate is detected as the viscosity state.
Further, the temperature of the semi-cured sheet-like thermosetting resin is detected as the viscosity state.

  Furthermore, in the method for manufacturing an electronic device according to the present invention, the semi-cured sheet-shaped thermosetting mold is formed by heating and pressurizing a semi-cured sheet-shaped thermosetting resin between the plurality of first circuit components. A resin is cured to manufacture an electronic device in which the first circuit components are electrically connected, and the plurality of first circuit components provided with the semi-cured sheet-like thermosetting resin are heated. Pressurizing, detecting the viscosity state of the semi-cured sheet-like thermosetting resin, and increasing the heating / pressurizing force at a timing determined from the viscosity state. And

Further, the second circuit component is mounted on any of the first circuit components, and the second circuit component is embedded by the semi-cured sheet-like thermosetting resin.
The semi-cured sheet-like thermosetting resin is provided at any position between the plurality of first circuit components.

Further, at least one of the first circuit components is a bare IC chip.
Further, at least one of the first circuit components is made of a ceramic material or a glass material.

  As described above, problems such as breakage of circuit components embedded in the semi-cured sheet-like thermosetting resin and poor electrical connection between the circuit components can be eliminated.

  As described above, during hot pressing, the viscosity state of the thermosetting resin is detected by measuring the moving speed and acceleration of the press plate, the temperature of the object, etc., and the press pressure is increased from the viscosity state. By detecting the timing, it is possible to eliminate problems such as breakage of circuit components embedded in the thermosetting resin during hot pressing and poor electrical connection between circuit components.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment)
FIG. 1 is a diagram showing a configuration of a hot press apparatus of the present invention.

  In FIG. 1, 1 is a hot press mechanism. The hot press mechanism 1 includes a hot press plate (upper) 10a and a hot press plate (lower) 10b. Further, 11 is a semi-curable sheet-like thermosetting resin, and 12a and 12b are circuit components.

As the sheet-like thermosetting resin 11 that is usually used for the component-embedded substrate, a mixture containing 70% to 95% by weight of an inorganic filler and a thermosetting resin is used. As the inorganic filler, for example, Al ₂ O ₃ , MgO, BN, AlN, or SiO ₂ can be used. Moreover, the average particle diameter of the inorganic filler is 0.1 μm to 100 μm or less. For example, an epoxy resin, a phenol resin or a cyanate resin having high heat resistance is used as the thermosetting resin, and an epoxy resin is particularly preferable because it has particularly high heat resistance. The mixture may further contain a dispersant, a colorant, a coupling agent or a release agent. The minimum melt viscosity is often in the range of 1,000 to 10,000 Pa · s.

  Reference numeral 20 denotes a detection mechanism for examining the viscosity state of the sheet-like thermosetting resin 11, reference numeral 30 denotes a data processing mechanism, and reference numeral 40 denotes a control mechanism. Reference numeral 21 denotes a detection signal that is an output signal from the detection mechanism 20, reference numeral 31 denotes a data signal that is an output signal from the data processing mechanism 30, and reference numeral 41 denotes a control signal for controlling the hot press mechanism 1. Is shown.

  In the above-described configuration, first, the detection mechanism 20 detects various displacement amounts necessary for measuring the viscosity state of the sheet-like thermosetting resin 11 that is hot-pressed by the hot-press mechanism 1. As the displacement amount to be detected, for example, the thickness of a structure that is hot-pressed including the sheet-like thermosetting resin 11, the amount of protrusion to the periphery of the sheet-like thermosetting resin 11, or the sheet-like thermosetting There is a temperature of the mold resin 11, but any other method can be used as long as it can measure the viscosity state of the sheet-like thermosetting resin 11. Moreover, as the detection mechanism 20, a mechanism that contacts the sheet-like thermosetting resin 11 is not preferable. This is because the sheet-like thermosetting resin 11 is finally cured and cannot be removed.

  The detection signal 21 output from the detection mechanism 20 is input to the data processing mechanism 30 and subjected to appropriate data processing. For example, data on the amount of displacement by which the sheet-like thermosetting resin 11 is crushed is processed into speed and acceleration data. The processed data is input to the control mechanism 40 as a data signal 31. The control mechanism 40 generates a control signal 41 for controlling at least one of heating and pressurization of the hot press mechanism 1 in accordance with the data signal 31 in accordance with a pre-input condition, thereby heating or pressurizing the hot press mechanism 1. To control.

  In this embodiment, when detecting the displacement amount by which the sheet-like thermosetting resin 11 is crushed as the detection mechanism 20, specifically, a method of measuring the movement amount of the upper and lower hot press plates 10a and 10b. There is.

FIG. 2 shows an example of a specific system configuration.
FIG. 2 is a diagram illustrating the configuration of a hot press mechanism that controls the press mechanism by the amount of movement of the hot press plate according to the present invention.

  In FIG. 2, 50 is a linear scale, 51 is a data conversion device, 52 is a sampling device, and 53 is a control mechanism personal computer. In the hot press mechanism 1 of FIG. 2, the lower hot press plate 10b is fixed, and only the upper press plate 10a is movable. The components described in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In the system configured as described above, as a displacement amount of the upper press plate 10 (a) that moves and displaces according to the viscosity state of the sheet-like thermosetting resin 11, for example, movement of a mark provided on the upper press plate 10a The quantity is converted into an analog electrical signal by the linear scale 50. The converted analog electric signal is converted into a digital electric signal by the data converting device 51, extracted at a predetermined sampling rate by the sampling device 52, and input to the control mechanism personal computer 53 that controls the control mechanism. Predetermined data processing is performed and a control signal 41 is transmitted to the heat press mechanism 1. In the actual component built-in substrate process, the thickness of the sheet-like thermosetting resin 11 is increased by 0.5 mm to 0.5 mm by heat pressing at 200 ° C. and 3 Mpa, so that the thickness is reduced by about 0.1 mm. The hot press plate 10a moves about 0.1 mm before and after the hot press. Here, the movement amount of the upper press plate 10a is used as the displacement amount, but it is also possible to obtain the acceleration from the movement amount per unit time and use this acceleration as the movement amount.

Moreover, when detecting the temperature of the sheet-like thermosetting resin 11, there is a method of measuring with an infrared radiation thermometer.
FIG. 3 shows an example of a specific system configuration.

FIG. 3 is a diagram illustrating the configuration of a hot press mechanism that controls the press mechanism according to the temperature of the sheet-like thermosetting resin in the present invention.
In FIG. 3, 60 is an infrared radiation thermometer, 61 is a setting indicator, and 62 is a control mechanism personal computer. Here, the components described in FIGS. 1 and 2 are denoted by the same reference numerals and description thereof is omitted.

  In the system configured as described above, the actual temperature of the surrounding surface in the sheet-like thermosetting resin 11 is measured by an infrared radiation thermometer in a non-contact manner. The temperature is displayed on the setting display 61 and is input to the control mechanism personal computer 62 that controls the control mechanism at a predetermined sampling rate, performs predetermined data processing, and transmits a control signal 41 to the heat press mechanism 1.

  In the present embodiment, the circuit component 12a and the circuit component 12b include a wiring board such as a normal printed wiring board and a ceramic wiring board, a passive component such as a chip part, and a semiconductor component in a package form. All circuit components constituting an electronic device such as a wiring board on which electronic components are mounted and a bare IC chip are included.

In particular, in the case of a mounted wiring board, a circuit component built-in substrate is formed, and in the case of a bare IC chip, a flip chip mounting body is formed.
Next, an example of the control method of the hot press apparatus in the hot press process in the manufacturing method of the electronic component device according to the embodiment of the present invention will be described with reference to FIG.

  FIG. 4 is a view for explaining a control method of the hot press apparatus in the method for manufacturing an electronic component device according to the present invention. FIG. 4 (a) is a melt viscosity of a sheet-like thermosetting resin used for a circuit component built-in substrate. FIG. 4 (b) shows the characteristics, and the movement of the press plate in the process of forming the electronic device structure while embedding circuit components in the sheet-like thermosetting resin and then performing electrical connection. The relationship between speed and press pressure is shown.

  First, FIG. 4A will be described. In FIG. 4A, the horizontal axis indicates the elapsed time under a certain temperature environment, and the vertical axis indicates the melt viscosity. As described with reference to FIG. 7, the semi-cured sheet-like thermosetting resin starts to press and then starts to decrease in viscosity when subjected to certain heating. When the heating is further continued, the resin begins to harden and the viscosity starts to rise to reach a saturated state.

  Therefore, as shown in FIG. 4 (b) using the heat press apparatus of the present invention, the sheet-like thermosetting resin becomes less than a certain viscosity by detecting the movement speed of the heat press plate, and the movement speed of the heat press plate is reduced. Control is performed to increase the press pressure from P1 to P2 when the pressure increases and exceeds the displacement speed change point V1 inputted in advance.

  Here, the viscosity is a resistance exhibited by the fluid when a force is applied to the fluid such as a liquid, and is proportional to the gradient of the moving speed of the hot press plate in this case. As a result, as described above, since the viscosity changes depending on the changing point of the moving speed of the hot press plate, the press load is increased.

  In this way, during hot pressing, a sheet that is actually hot pressed by detecting the viscosity state of the thermosetting resin by measuring the moving speed and acceleration of the press plate or the temperature of the object. Circuit can be embedded in the sheet-like thermosetting resin because the thermo-pressing device can be controlled such as shifting the pressing pressure when the temperature of the thermosetting resin is exactly below a certain viscosity. It is possible to prevent the occurrence of problems such as breakage of parts and poor electrical continuity between circuit parts.

  In addition, when the circuit component is a bare IC chip, the mechanical strength is weak in recent years due to the use of a fragile insulating layer material resulting from performance requirements for the bare IC chip and the thinning resulting from the small size and thinness requirement of electronic equipment. Although it has become a structure, it is not damaged in the thermocompression bonding step, and a flip-chip mounting body can be manufactured satisfactorily.

  In addition, even in a configuration using a wiring board that is more easily broken than a printed wiring board made of resin, such as a ceramic wiring board or a glass wiring board, it is not cracked in the hot press process, and therefore, LTCC made of a ceramic material is used. In many cases, an RF module mounted on a mobile phone or the like, a display module using a glass wiring board, and the like can be manufactured favorably.

  Here, it is not necessary to provide the thermosetting resin on the entire surface between the circuit components, and it is sufficient if the thermosetting resin is provided at any necessary position.

  The present invention can eliminate problems such as breakage of circuit components embedded in a semi-cured sheet-like thermosetting resin and poor electrical connection between circuit components, and a circuit component built-in substrate, flip chip It is useful for a heat press apparatus used for production of an electronic device such as a mounting body, a method for manufacturing an electronic device using the same, and the like.

It is a figure which shows the structure of the hot press apparatus of this invention. The figure which illustrates the structure of the hot press mechanism which controls a press mechanism by the amount of hot press board movement of this invention The figure which illustrates the structure of the hot press mechanism which controls a press mechanism with the temperature of the sheet-like thermosetting resin in this invention. The figure explaining the control method of the hot press apparatus in the manufacturing method of the electronic component apparatus of this invention Process cross-sectional view showing the method of manufacturing a circuit component built-in substrate Process diagram showing the manufacture of flip chip mounting body The figure which shows the melt viscosity characteristic of the semi-cured sheet-like thermosetting resin

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hot press mechanism 10a Hot press board 10b Hot press board 11 Sheet-like thermosetting resin 12a Circuit component 12b Circuit component 20 Detection mechanism 21 Detection signal 30 Data processing mechanism 31 Data signal 40 Control mechanism 41 Control signal 50 Linear scale 51 Data Control device 52 Sampling device 53 Control mechanism personal computer 60 Infrared radiation thermometer 61 Setting indicator 62 Control mechanism personal computer 100 Circuit component built-in substrate 101 Composite sheet 102 Via paste 103a Printed wiring board 103b Printed wiring board 104 Chip component 200 Flip chip mounting Body 201 Bare IC chip 202 Stud bump 203 Printed wiring board 204 Sealing adhesive film

Claims (10)

Forming an electronic device structure by curing the semi-cured sheet-like thermosetting resin by heating and pressing in a state where a semi-cured sheet-like thermosetting resin is provided between a plurality of circuit components,
A hot press mechanism comprising a pair of hot press plates for heating and pressurizing the plurality of circuit components provided with the semi-cured sheet-like thermosetting resin;
A detection mechanism for detecting the viscosity state of the semi-cured sheet-like thermosetting resin;
And a control mechanism for generating a control signal for the hot press mechanism from the detected viscosity state, and the hot press mechanism is controlled by the control signal.   2. The hot press apparatus according to claim 1, wherein the control of the hot press mechanism is to increase the pressing force of the hot press mechanism.   The hot press apparatus according to claim 1, wherein a moving speed of the hot press plate is detected as the viscosity state.   The hot press apparatus according to claim 1, wherein a movement acceleration of the hot press plate is detected as the viscosity state.   The hot press apparatus according to claim 1, wherein a temperature of the semi-cured sheet-like thermosetting resin is detected as the viscosity state. Between the first circuit components, the semi-cured sheet-like thermosetting resin is cured by heating and pressing in a state where a semi-cured sheet-like thermosetting resin is provided between the plurality of first circuit components. Manufactures electronic devices that are electrically connected,
Heating and pressurizing the plurality of first circuit components provided with the semi-cured sheet-like thermosetting resin;
Detecting the viscosity state of the semi-cured sheet-like thermosetting resin;
And a step of increasing the pressure of the heating and pressurization at a timing determined from the viscosity state.   The second circuit component is mounted on any one of the first circuit components, and the second circuit component is embedded by the semi-cured sheet-like thermosetting resin. Method for manufacturing the electronic device.   8. The method of manufacturing an electronic device according to claim 6, wherein the semi-cured sheet-like thermosetting resin is provided at an arbitrary position between the plurality of first circuit components. .   9. The method of manufacturing an electronic device according to claim 6, wherein at least one of the first circuit components is a bare IC chip.   The method for manufacturing an electronic device according to claim 6, wherein at least one of the first circuit components is made of a ceramic material or a glass material.

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