KR20210039620A - Temperature Sensing Module of Laser Reflow Device - Google Patents

Abstract

The present invention relates to a temperature sensing module of a laser reflow apparatus for bonding electronic components to a substrate by pressing a plurality of electronic components arranged on the substrate with a light-transmitting pressing member and, at the same time, irradiating a laser beam through the pressing member. According to the present invention, the temperature sensing module comprises: a plurality of IR temperature sensors passing through the light-transmitting pressing member to measure thermal energy applied to an electronic component; a body part having a hinge fixed to one side of the inside and fixing one of the plurality of IR temperature sensors in a vertical direction; a support part for supporting the remaining IR temperature sensors except for the IR temperature sensor fixed in the vertical direction; and a tilt part connected to the body part and the support part to be tilted at a predetermined angle.

Description

Temperature Sensing Module of Laser Reflow Device

The present invention relates to a laser reflow apparatus, and more particularly, in a laser reflow apparatus having a multi-laser beam module that overlaps and irradiates at least two or more laser beams, the temperature of a laser beam region to which the multi-laser beams overlap and irradiate. The present invention relates to a laser pressurizing head module of a laser reflow apparatus capable of minimizing bonding defects due to temperature imbalance of electronic components included in a bonding object by precisely monitoring distribution.

Micro laser processing is an application field with micron (㎛) precision in industrial laser processing, and is widely used in the semiconductor industry, the display industry, the printed circuit board (PCB) industry, and the smartphone industry. Memory chips used in all electronic devices have developed a technology that minimizes the circuit spacing in order to realize the integration, performance and ultra-high communication speed, but now the required technology level is achieved simply by reducing the circuit line width and line width interval. It was difficult to do so, so it became the level of stacking memory chips in a vertical direction. The stacking technology up to 128 layers has already been developed by TSMC, and the technology of stacking up to 72 layers is being applied to mass production at Samsung Electronics and SK Hynix.

In addition, technology development to mount memory chips, microprocessor chips, graphic processor chips, wireless processor chips, and sensor processor chips in one package is being intensively researched and developed, and a considerable level of technologies are already being applied in practice.

However, in the process of development of the above-mentioned technology, since more and more electrons have to participate in the signal processing process inside the ultra-high speed/ultra-high capacity semiconductor chip, the power consumption increases, and the issue of cooling treatment for heat has been raised. In addition, a technical issue has been raised that a large amount of electrical signals must be transmitted at an ultra-high speed in order to achieve the requirements of ultra-high-speed signal processing and ultra-high-frequency signal processing for more signals. In addition, since the number of signal lines must be increased, the signal interface lines to the outside of the semiconductor chip can no longer be processed by the one-dimensional lead wire method, but the Fan-In BGA method (Fan-In BGA), which processes two-dimensionally under the semiconductor chip. Or Fan-in Wafer-Level-Package (FIWLP)), and a Signal Layout Redistribution Layer under the ultra-fine BGA layer under the chip, and a second fine BGA layer under the chip. The method (referred to as Fan-Out BGA or Fan-Out Wafer-Level-Package (FOWLP) or Fan-Out Panel-Level-Package) has been successfully applied.

Recently, in the case of semiconductor chips, products with a thickness of 200 μm or less including an EMC (Epoxy-Mold Compound) layer have appeared. In order to attach a micron-class ultra-thin semiconductor chip with a thickness of only a few hundred microns to an ultra-thin PCB, mass reflow (such as Thermal Reflow Oven) technology, a standard process for surface mount technology (SMT). When applying MR) process, semiconductor chips are exposed in an air temperature environment of 100 to 300 degrees Celsius (℃) for hundreds of seconds, so chip-boundary warpage (PCB) due to differences in coefficient of thermal expansion (CTE) -Various types of soldering bonding defects such as PCB-Boundary Warpage and Random-Bonding Failure by Thermal Shock may occur.

Accordingly, looking at the configuration of a laser reflow device that has recently been in the spotlight, a laser head module presses a bonding object (semiconductor chip or integrated circuit IC) for several seconds and irradiates a laser for bonding. (IC) Bonding is performed by irradiating a laser in the form of a surface light source corresponding to the size.

In this process, it includes an IR temperature sensor to monitor heat applied to electronic components such as semiconductor chips during laser irradiation. That is, the IR temperature sensor is for detecting heat generated by a laser irradiated to an electronic component, and senses the temperature in a vertical direction.

In this case, the IR temperature sensor senses the temperature sensed from the electronic component in a plurality of forms, and the controller receives the temperature and calculates it as an average value. Then, the calculated value is determined and the laser output is controlled.

However, since the IR temperature sensor is measured only in the vertical direction, it is impossible to calculate a more accurate average value for electronic components that are out of the range that can be measured. This eventually causes a problem in controlling the laser output by the control unit generating a malfunction signal. For example, despite the fact that the heat applied to the electronic component is actually high, the possibility of burning or damaging the electronic component is high because the laser cannot be controlled in time.

Accordingly, the present invention has been invented to solve the above problems, and has an object to measure various sizes of electronic components by allowing the IR temperature sensor to be tilted at a predetermined angle.

In addition, another object of the present invention is to accurately control the laser output by more accurately measuring heat applied to an electronic component.

In order to achieve the above object, the present invention provides a laser reflow for bonding electronic components to a substrate by pressing a plurality of electronic components arranged on a substrate with a light-transmitting pressing member and irradiating a laser beam through the pressing member. A temperature sensing module of a device, comprising: a plurality of IR temperature sensors for measuring thermal energy applied to an electronic component by passing through the light-transmitting pressing member; A body portion having a hinge fixed to one side of the inner side and fixing one of the plurality of IR temperature sensors in a vertical direction; a support portion supporting the remaining IR temperature sensors excluding the IR temperature sensor fixed in the vertical direction; the body portion and the support It includes; a tilt unit that is connected to the additional inclined at a predetermined angle.

The present invention further includes a control unit that detects heat energy applied to an electronic component from the plurality of IR temperature sensors, calculates an average value, and determines whether or not it is within a preset value range.

The present invention has the effect of measuring various sizes of electronic components by allowing the IR temperature sensor to be tilted at a certain angle.

The present invention has the effect of accurately controlling laser output by more accurately measuring heat applied to an electronic component.

1 is an exemplary view showing the overall configuration of a laser pressurizing head module of the laser reflow apparatus of the present invention
2 is a block diagram of FIG. 1
3 is a conceptual diagram of a single laser module according to an embodiment of the present invention laser pressure head module
4 is a conceptual diagram of a multi-laser module according to another embodiment of the present invention laser pressurizing head module
5 is a block diagram of a multi-laser module according to another embodiment of the present invention laser pressurizing head module
6 to 9 are configuration diagrams of a laser optical system applicable to a multi-laser module according to another embodiment of the present invention.
10 is a side view schematically showing the configuration and operation relationship of a multi-laser module according to another embodiment of the present invention
11 is a perspective view showing an enlarged view of the configuration of the IR temperature sensor of FIG. 10
12 is a plan view showing an enlarged view of the configuration of the bonding object of FIG. 11

The terms used in the present specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present specification, terms such as "include" or "have" to "include" are intended to designate the presence of features, numbers, steps, actions, components, parts, or a combination thereof described in the present specification. It is to be understood that the possibility of the presence or addition of other features, numbers, steps, actions, components, parts, or combinations thereof, or any further features, is not excluded in advance.

Unless otherwise defined in the specification, all terms including technical or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in the present specification. Shouldn't.

Hereinafter, a reflow apparatus according to the present invention will be described in detail with reference to FIGS. 1 and 2.

The laser pressurizing head module 300 of the laser reflow apparatus according to the present invention, as shown in FIGS. 1 and 2, includes a porous material having a structure capable of applying heat to the lower portion or a stage 111 having a vacuum hole. ) At least one multi-laser module (310, 320) that irradiates a surface light source type laser to the bonding object 11 that is supported and transported, and is installed independently from the laser module (310, 320), and is a surface light source. It is configured to include a light-transmitting pressurizing member 100 that transmits the type of laser, and a protective film 200 that protects the light-transmitting pressurizing member 100 from contamination.

First, the plurality of multi-laser modules 310 and 320 convert the laser generated by the laser oscillator and transmitted through the optical fiber into a surface light source to irradiate the bonding object 11. The laser modules 310 and 320 include a beam shaper that converts a spot-shaped laser into a surface light source (see FIG. 5), and a surface light source that is disposed under the beam shaper and emitted from the beam shaper is a bonding object ( A plurality of lens modules may be implemented by including an optical unit (see FIGS. 5 to 9) that are spaced apart from each other and mounted inside the barrel so as to be irradiated to the irradiation area of 11).

The laser modules 310 and 320 may rise or fall along the z-axis, move left or right along the x-axis, or move along the y-axis for alignment with the bonding object 11.

The pressure head 300 of the laser reflow apparatus according to the present invention includes a translucent pressure member 100 that presses the bonding object 11 and a laser module 310 and 320 that irradiates a surface light source type laser to the bonding object 11. ) Are formed to be separated from each other, so that the laser modules 310 and 320 are moved to a plurality of irradiation positions of the bonding object 11 while pressing the bonding object 11 with the translucent pressing member 100 and then driven. By doing so, it is possible to shorten the tact time for one bonding object 11 and speed up the bonding operation for all of the plurality of bonding objects 11.

At this time, the light-transmitting pressing member 100 is moved to a working position or a standby position by a light-transmitting pressing member conveying unit (not shown in the drawing) of a predetermined type, for example, the translucent pressing member conveying unit lowering or It can be raised or moved to the left or right and then lowered or raised.

In addition, although not shown in the drawing, the laser pressure head module 300 of the laser reflow apparatus according to the present invention uses data input from a pressure sensor (not shown) and a height sensor (not shown) to transmit a light-transmitting pressure member. It further includes a control unit (not shown) for controlling the operation of the transfer unit.

The pressure sensing sensor and the height sensor may be installed on the light-transmitting pressing member 100, the light-transmitting pressing member transfer unit, and the stage 111 supporting the bonding object. For example, the control unit may receive data from the pressure sensor and control the light-transmitting pressurizing member transfer unit so that the pressure reaches the target value, and also control the light-transmitting pressurization member transfer unit to receive data from the height sensor and reach the target height.

In addition, the support (not shown) supports the translucent pressing member transfer unit (not shown) to be movable. As an example, the support unit may be implemented as a pair of gantry extending parallel to the stage 111, and includes a configuration that supports the translucent pressing member transfer unit to be movable in the x-axis, y-axis, or z-axis. It should be interpreted as being.

The pressure head 300 of the laser reflow device according to the present invention includes at least one actuator that applies pressure to the light-transmitting pressure member 100 and at least one pressure sensor that senses the pressure applied to the light-transmitting pressure member 100, and a light-transmitting device. It may be implemented by including one or more height sensors for detecting the height of the pressing member. The pressure sensor may be implemented with at least one load cell as an example, and the height sensor may be implemented with a linear encoder.

By adjusting the pressure applied to the object to be bonded through the pressure sensor, in the case of a large area, it is possible to control so that the same pressure can be transmitted to the object to be bonded through a plurality of actuators and a plurality of pressure sensors. Through the height sensor, it provides technical data to check the height position value at the moment when the object to be bonded is bonded or to find a more accurate value of the bonding height. It performs a function that can be controlled.

In addition, the translucent pressing member 100 may be implemented as a base material that transmits the laser output from the laser modules 310 and 320. The base material of the light-transmitting pressing member 100 can be implemented with any beam-transmitting material.

The base material of the light-transmitting pressing member 100 may be implemented by any one of, for example, quartz, sapphire, fused silica glass, or diamond. However, the physical characteristics of the light-transmitting pressing member made of quartz material are different from the physical characteristics of the light-transmitting pressing member made of sapphire. For example, when irradiating a 980 nm laser, the transmittance of the translucent pressing member made of quartz material is 85% to 99%, and the temperature measured at the bonding object is 100°C. On the other hand, the transmittance of the translucent pressurizing member made of sapphire is 80% to 90%, and the temperature measured at the bonding object is 60°C.

That is, in terms of light transmittance and heat loss required for bonding, quartz shows superior performance than sapphire. However, the inventors of the present application have repeatedly tested the translucent pressurizing member 100 while developing the laser reflow device. As a result, the translucent pressurizing member 100 made of a quartz material is cracked during laser bonding. It has been found that there is a problem in that the bonding quality is defective due to the occurrence of burning on the floor or the bottom surface. It was analyzed that gases generated during laser bonding adhered to the bottom surface of the light-transmitting pressurizing member 100, and the heat source of the laser was concentrated in a portion to which fumes adhered to increase thermal stress.

In order to prevent damage and improve durability of the light-transmitting pressurizing member 100 made of a quartz material, a thin film coating layer may be formed on the bottom surface of the light-transmitting pressurizing member made of a quartz material. The thin film coating layer formed on the bottom surface of the light-transmitting pressing member 100 may be implemented as a conventional optical coating, such as dielectric coating, SiC coating, or metallic material coating.

In the laser pressurizing head module 300 of the laser reflow apparatus according to the present invention, as shown in FIG. 1, gases generated during laser bonding are transmitted to the lower portion of the translucent pressurizing member 100. ) Is implemented to further include a protective film 200 to prevent sticking to the bottom surface of the protective film 200 and a protective film transfer unit 210 for transporting the protective film 200.

The protective film transfer unit 210 may be implemented in a reel-to-reel method in which the protective film 200 wound in a roll shape is released and transferred to one side. As an example, the protective film 200 is preferably implemented with a material having excellent heat resistance with a maximum use temperature of 300 degrees Celsius or more and a continuous maximum use temperature of 260 degrees Celsius or more. For example, the protective film 200 may be implemented with a polytetrafluoroethylene resin (commonly referred to as a Teflon resin; Polytetrafluoroethylene, PTFE) or a purple alkoxy resin. Per Fluoro Alkylvinyether copolymer (PFA) is a product that improves the heat resistance of fluorinated ethylene propylene resin, and it is a highly functional resin with a continuous maximum operating temperature of 260 degrees Celsius like polytetrafluoroethylene resin.

3 is a conceptual diagram of a single laser module according to an embodiment of the present invention bonding object transport module, Figure 4 is a conceptual diagram of a dual laser module according to another embodiment of the present invention bonding object transport module.

Referring to FIG. 3, the present invention includes a single laser module 310 according to an embodiment, and thus a single laser beam is irradiated onto the FPCB substrate. In this case, referring to FIG. 3, the laser beam irradiated by the first laser module 310 is irradiated on the substrate in a state in which the intensity of the laser beam is transformed into a homogenized square beam shape.

Meanwhile, referring to FIG. 4, a multi-laser module according to another embodiment of the present invention includes, for example, a first laser module 310 and a second laser module 320, and is an electronic component of the bonding object 11. At the attached position, the first and second laser modules are irradiated in a superimposed state to irradiate a homogenized superimposed laser beam.

In FIG. 4, it is illustrated that the first laser beam has a square shape and the second laser beam has a circular shape, but both laser beams may have a square shape. In addition, the first laser beam and the second laser beam may be irradiated at the same time, or the second laser beam may be sequentially irradiated after preheating of the bonding object 11 by the first laser beam.

5 is a block diagram of a dual laser module according to another embodiment of the present invention pressure head.

In FIG. 5, each of the laser modules 310, 320, ... 330 is a laser oscillator 311, 321, 331, each having a cooling device (316, 326, 336), a beam shaper (312, 322, 332) , Optical lens modules 313, 323, 333, driving devices 314, 324, 334, control devices 315, 325, 335, and power supply units 317, 327, 337.

Hereinafter, the first laser module 310 of each laser module having the same configuration will be mainly described in order to avoid redundant description, except when necessary.

The laser oscillator 311 generates a laser beam having a wavelength and output power in a predetermined range. The laser oscillator is, for example, a diode laser (Laser Diode (LD)) having a wavelength of '750nm to 1200nm' or '1400nm to 1600nm' or '1800nm to 2200nm' or '2500nm to 3200nm' or a rare earth medium fiber laser (Rare-Earth- Doped Fiber Laser) or Rare-Earth-Doped Crystal Laser. Alternatively, a medium for emitting alexandrite laser light having a wavelength of 755 nm, or Nd Yag (Nd) having a wavelength of 1064 nm or 1320 nm. :YAG) It may be implemented including a medium for emitting laser light.

A beam shaper 312 converts a spot-shaped laser generated in a laser oscillator and transmitted through an optical fiber into an area beam having a flat top. The beam shaper 312 may be implemented by including a Square Light Pipe, a Diffractive Optical Element (DOE), or a Micro-Lens Array (MLA).

The optical lens module 313 adjusts the shape and size of a laser beam converted into a surface light source form by a beam shaper to irradiate it to an electronic component or an irradiation area mounted on a PCB substrate. The optical lens module constitutes an optical system through a combination of a plurality of lenses, and a specific configuration of such an optical system will be described later in detail with reference to FIGS. 6 to 9.

The driving device 314 moves the distance and position of the laser module with respect to the irradiation surface, and the control device 315 controls the driving device 314 to control the beam shape and the beam area size when the laser beam reaches the irradiation surface. , Adjust the beam sharpness and beam irradiation angle. The control device 315 may also integrally control the operation of each unit of the laser module 310 in addition to the driving device 314.

Meanwhile, the laser output adjustment unit 370 is supplied to each laser module from the power supply units 317, 327, 337 corresponding to each laser module 310, 320, 330 according to a program received through a user interface or a preset program. Controls the amount of power to be used. The laser output adjustment unit 370 receives information on the reflow status of each part, area, or entire reflow on the irradiation surface from one or more camera modules 350 and controls each power supply unit 317, 327, 337 based on this. In contrast, the control information from the laser output control unit 370 is transmitted to the control devices 315, 325, 335 of each laser module (310, 320, 330), and each control device (315, 325, 335) It is also possible to provide a feedback signal for controlling the corresponding power supply unit 317. In addition, unlike FIG. 6, it is possible to distribute power to each laser module through one power supply unit. In this case, the power supply unit must be controlled by the laser output adjustment unit 370.

When implementing the laser superimposition mode, the laser power adjustment unit 370 includes each laser module and the laser module so that the laser beam from each laser module 310, 320, 330 has a required beam shape, a beam area size, beam sharpness, and a beam irradiation angle. Controls the power supply units 317, 327, and 337. In addition to the case of preheating the area around the debonding target position using the first laser module 310 and additionally heating the narrower reflow target area using the second laser module 320, the preheating function or The additional heating function is appropriately distributed among the first, second, and third laser modules 310, 320, ... 330 to control each laser module to have a required temperature profile.

Meanwhile, when a single laser light source is distributed and input to each laser module, a function for simultaneously adjusting the output and phase of each distributed laser beam may be provided in the laser output adjusting unit 370. In this case, the beam flatness can be remarkably improved by controlling the phase to induce destructive interference between the respective laser beams, thereby further increasing energy efficiency.

On the other hand, in the case of implementing a multi-position simultaneous processing mode, the laser power adjustment unit 370 is used to ensure that some or all of the laser beams from each laser module are different. Controls one or more of the angle and the beam wavelength. Even at this time, in the case of distributing one laser light source and inputting it to each laser module, the laser output adjusting unit 370 may have a function for simultaneously adjusting the output and phase of each of the distributed laser beams.

Through this function, bonding between the electronic components in the irradiation surface and the substrate can be performed or the bonding can be removed by adjusting the laser beam size and output. In particular, in the case of removing damaged electronic components on the substrate, the application of heat by the laser beam to other adjacent electronic components or normal electronic components existing on the substrate can be minimized by minimizing the area of the laser beam to the corresponding electronic component area. Accordingly, it is possible to remove only the damaged electronic component to be removed.

On the other hand, in the case of emitting laser beams with different wavelengths for each of the plurality of laser modules, the laser module will absorb a plurality of material layers (e.g., EMC layer, silicon layer, solder layer) included in the electronic component. It can be composed of individual laser modules with wavelengths. Accordingly, the laser debonding device according to the present invention selectively increases the temperature of the electronic component and the temperature of the intermediate bonding material such as solder, which is a connecting material between the printed circuit board or the electrode of the electronic component, to be optimized for bonding (Attaching or Bonding) or separation (detaching or debonding) process may be performed. Specifically, by transmitting both the EMC mold layer and the silicon layer of the electronic component so that all the energy of each laser beam is absorbed by the solder layer, or the laser beam does not pass through the EMC mold layer and heats the surface of the electronic component, the lower part of the electronic component It is also possible to conduct heat to the bonding portion of the.

Meanwhile, by utilizing the above functions, after preheating the area of the electronic component to be reflowed and a certain area of the substrate including the periphery thereof by at least one first laser beam to a predetermined preheating temperature, at least one second laser beam Accordingly, the temperature of the electronic component region to be reflowed is selectively heated to the reflow temperature at which solder melting occurs.

6 to 9 are configuration diagrams of a laser optical system applicable to a single laser beam or a multi-laser module of the bonding object transfer module of the present invention.

6 is an optical system having the simplest structure applicable to the present invention. When the laser beam emitted from the beam transmission optical fiber 410 is focused through the convex lens 420 and incident on the beam shaper 430, the beam shaper 430 ), the spot-shaped laser beam is converted to a flat-top type surface light source (A1), and the square laser beam (A1) output from the beam shaper 430 is the desired size through the concave lens 440 The image-forming surface S is irradiated with the enlarged surface light source A2.

7 is a block diagram of a laser optical system according to another embodiment of the present invention.

The surface light source B1 from the beam shaper 430 is enlarged to a predetermined size through the concave lens 440 to become a surface light source B2 irradiated to the first imaging surface S1. When the surface light source (B2) is to be further enlarged and used, the boundary of the edge portion of the surface light source (B2) may become more unclear according to the additional expansion, so that the final irradiation surface is the second imaging surface (S2). ) In order to obtain irradiation light with a clear edge, a mask 450 is installed on the first imaging surface S1 to trim the edge.

The surface light source passing through the mask 450 is reduced (or enlarged) to a desired size while passing through the zoom lens module 460 composed of a combination of at least one convex lens and a concave lens, and the second imaging surface on which the electronic component is placed Square irradiation light B3 is formed in (S2).

8 is a block diagram of a laser optical system according to another embodiment of the present invention.

After the square surface light source C1 from the beam shaper 430 is enlarged to a predetermined size through the concave lens 440, it is enlarged (or reduced) in the x-axis direction, for example, passing through at least a pair of cylindrical lenses 470 (C2) and again passing through at least a pair of cylindrical lenses 480, it is reduced (or enlarged) in the y-axis direction, for example, and converted into a rectangular surface light source C3.

Here, the cylindrical lens is a shape obtained by cutting a cylindrical shape in the longitudinal direction, and functions to expand or reduce the laser beam according to the shape in which each lens is arranged in the vertical direction, and the lens on the surface on which the cylindrical lens is placed is x, y Depending on the shape arranged in the axial direction, the laser beam is adjusted in the x-axis or y-axis direction.

Subsequently, the surface light source C3 is enlarged (or reduced) to a desired size while passing through the zoom lens module 460 composed of a combination of at least one convex lens and a concave lens, and the second imaging surface S2 on which the electronic component is disposed. ) To form a rectangular irradiation light C4.

FIG. 10 is a side view schematically showing the configuration and operation relationship of a multi-laser module according to another embodiment of the present invention, FIG. 11 is a perspective view showing an enlarged configuration of a temperature sensor of FIG. 10, and FIG. 12 is It is a plan view of the main part shown by expanding the composition of the object to be bonded.

Hereinafter, a configuration and operation relationship of a multi-laser module according to another embodiment of the present invention will be described with reference to FIGS. 10 to 12.

First, referring to FIG. 10, a multi-laser module according to another embodiment of the present invention includes a pair of first laser modules 310 and second laser modules 320, and the first laser module 310 and the second laser module 310 An IR temperature sensor is provided between the laser modules 320 to measure the temperature of the laser beam superimposedly irradiated from the first and second laser modules 310 and 320.

Meanwhile, the first laser module 310 and the second laser module 320 are provided with beam profilers 318 and 328, respectively, so that the laser beam output and intensity of the first and second laser modules 310 and 320 are provided. Are monitored at all times. The configuration of the beam profilers 318 and 328 is, for example, a laser beam provided on the laser beam path of the first and second laser modules 310 and 320 by irradiating or transmitting a part of the output laser beam to the beam profiler. You can measure the power and intensity of the beam.

The IR temperature sensor may be a single IR temperature sensor according to an embodiment, and the single infrared sensor measures a surface temperature value of the area 12 to which the laser beam is overlapped and irradiated from the first and second laser modules. It is done. In this case, the single IR temperature sensor measures the overall temperature distribution value of the overlapping irradiation area of the laser beam by sequentially measuring a plurality of points among the overlapping irradiated areas of the laser beam.

If such a temperature distribution value is measured to be non-uniform, for example, at a point where the temperature value is measured higher than the solder melting temperature at one point, an overflow bonding defect may occur due to overheating of the solder. Conversely, if the measurement is lower than the solder melting temperature, bonding failure may occur in which the solder cannot be sufficiently melted and connected.

To this end, in the present invention, the IR temperature sensor measures the temperature of the overlapped irradiated area at all times, so that the output or intensity of each laser beam output from the first or second laser module 310, 320, the shape of the beam, etc. Is adjusted to compensate for the temperature distribution value in the overlapped irradiation area 12.

Meanwhile, as another embodiment of the present invention, it is possible to provide a plurality of IR temperature sensors. Referring to FIG. 11, a plurality of IR temperature sensors of the present invention may be made of, for example, five IR temperature sensors (810#1, 810#2, 810#3, 810#4, 810#5), and have a rectangular arrangement. In the structure, one IR temperature sensor (810#1, 810#2, 810#3, 810#4) is disposed at each corner, and one IR temperature sensor (810#5) is disposed in the center. It can be a structure.

In more detail, the central IR temperature sensor may include a body portion that is fixed in a vertical direction. And, it may be included as a support for supporting the rest of the IR temperature sensor except for the IR temperature sensor fixed in the vertical direction. In this case, the body portion and the support portion may be connected to include a tilt portion to incline at a predetermined angle.

These IR temperature sensors 810#1, 810#2, 810#3, 810#4, and 810#5 simultaneously irradiate an infrared beam, and in this case, as shown in FIG. Infrared beam is irradiated and temperature is measured on the electronic components (11b#1, 11b#3, 11b#7, 11b#9) located at each corner of 12) and the electronic component (11b#5) located at the center. .

In this case, as described above, the location or number of the electronic components 11b for which the temperature is to be measured is not specified, and the temperature of the surface of the substrate on which the electronic component is not disposed may be measured. This can be achieved by measuring the temperature values of as many electronic components and substrates as possible in order to obtain a more accurate temperature distribution value of the area where the laser beam is overlapped and irradiated. At this time, the temperature distribution value refers to the average value of the measured temperature values, and the temperature measurement refers to the measurement of heat energy applied to the electronic component.

On the other hand, it is possible to compensate the temperature distribution value even when adjusting the irradiation angle and height of the first or second laser beam as another method for compensating the temperature distribution value described above.

In addition, the output of the laser beam can be controlled according to the temperature distribution value. In other words, it controls the output of the laser beam by determining whether it is within a preset temperature distribution value. For example, if the set temperature distribution value is 240 degrees and the actual measured temperature distribution value is 300 degrees, the control unit can control to lower the output of the laser beam.

The temperature sensing module of the reflow device further comprises a control unit configured to detect the thermal energy applied to the electronic component from the plurality of IR temperature sensors, calculate an average value, and determine whether or not it is within a preset value range.

In addition, the present invention is not limited only by the above-described embodiment, and since the same effect can be created even when the detailed configuration, number, and arrangement structure of the device is changed, those of ordinary skill in the art the present invention. It is stated that it is possible to add, delete, and transform various configurations within the scope of the technical idea of

11: bonding object 11a: substrate
11b: electronic component 12: laser overlap irradiation area
100: permeable pressing member 100a: pressing surface
200: protective film 210: protective film transfer unit
310: first laser module 320: second laser module
318, 328: beam profiler 810: IR temperature sensor
811: infrared irradiation point 812: hinge
814: body part 816: support part
818: tilt section

Claims (2)

In a temperature sensing module of a laser reflow apparatus for bonding an electronic component to a substrate by pressing a plurality of electronic components arranged on a substrate with a translucent pressing member and simultaneously irradiating a laser beam through the pressing member,
A plurality of IR temperature sensors for measuring heat energy applied to an electronic component through the translucent pressing member;
A body portion having a hinge fixed to one side of the inner side and fixing one of the plurality of IR temperature sensors in a vertical direction;
A support for supporting the rest of the IR temperature sensors except for the IR temperature sensor fixed in the vertical direction;
The temperature sensing module of the laser reflow apparatus comprising a; tilting portion connected to the body portion and the support portion inclined at a predetermined angle. The method of claim 1,
The temperature sensing module of the reflow device further comprises a control unit configured to detect thermal energy applied to the electronic component from the plurality of IR temperature sensors, calculate an average value, and determine whether or not it is within a preset range.

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