TWI765143B - Reflow and rework apparatus for electronic components - Google Patents

Abstract

The present invention relates to a reflow and rework apparatus for electronic components. The present invention comprises a stage on which a substrate on which an electronic component to be reflowed or reworked is mounted, a heating unit for heating an area including the electronic component to heat an electrical connection pattern provided on the electronic component, a laser irradiation unit for irradiating a laser on the electronic component to heat an electrical connection pattern provided on the electronic component, a control command input unit for receiving a process control command, and a controller for controlling the heating unit and the laser irradiation unit according to the process control command input received through the control command input unit to control the electronic components to be reflowed onto the substrate or to be reworked from the substrate.

Description

Reflow and Rework Equipment for Electronic Components

The present invention relates to a reflow and rework apparatus for electronic components. More specifically, the present invention relates to a reflow and rework apparatus for electronic components that stably reflows and reworks only a target electronic component to a substrate without affecting other electronic components, and reduces the amount of electricity required for reflowing solder balls such as the target electronic component. The time required for the connection pattern to reach its melting point reduces overall reflow and rework process time and improves product yield.

In addition, the present invention relates to a reflow and rework apparatus for electronic components that, in order to remove electronic components mounted on a printed circuit board, irradiates only a region of electronic components to be removed with a laser beam so that heat is not transmitted to adjacent electronic components, This makes it possible to remove only the electronic components that are the objects of removal.

Generally, electronic components including integrated circuit chips (ICs), manual components, etc. are reflowed to a printed circuit board by soldering through a reflow process, and when defects in the reflowed electronic components are found, The defective parts may be replaced with normal electronic parts after the defective parts are removed through a rework process. Of course, for reflow and rework, pads are provided on the printed circuit board, and solder balls corresponding to the pads are provided on the electronic component.

On the other hand, as shown in FIG. 1 , conventionally, for the reflow process and the rework process, a method of supplying hot air has been used as a method of heating the solder balls provided on the electronic component to the melting point.

However, this prior art has the following problems.

First, the hot air supplied during the rework or reflow process related to a specific electronic component is inevitably supplied to other electronic components adjacent to the above-mentioned specific component, so it is not subject to the rework or reflow process. other electronic components have adverse effects.

A specific explanation of this is as follows.

As shown in FIG. 1 , according to the prior art, when the target of rework is electronic component A, hot air for melting solder balls provided in electronic component A is supplied not only to electronic component A, but also to electronic component A. Since the adjacent electronic components B and C are supplied, the plurality of solder balls normally provided in the electronic components B and C are melted and adversely affect the electronic components B and C unintentionally.

Second, the conventional methods such as the above-mentioned hot air method apply radiant heat to the entire surface of the electronic component to be heated from a non-contact heat source, and the temperature of the mounting and soldering parts of the electronic component is gradually increased by the radiant heat. Therefore, from The time until the welding of the heating part is melted is too long. That is, in order to make the solder balls reach the melting point, the time for supplying the hot air is too long, so that the overall process time increases, and the product yield decreases.

Third, recently, very small-sized components have been mounted at high density on substrates, so, for example, in small wafer components (collectively referred to as 0201 size, ie, 0.2mm x 0.1mm or 0402 size, ie, 0.4mm x 0.2mm etc.), only local heating such as heating the corresponding part area is required, and the conventional method using a heat source such as hot air or a halogen or xenon lamp cannot take out the target part.

On the other hand, in electronic components such as semiconductor wafers with a thickness of 1,000 μm or more, in order to ensure self-weight and reliability characteristics, thick lead electrode wires (or lead wires) are wired on the side surfaces of the electronic components without arranging solder balls under the semiconductor wafer. ), which are usually electronic components that emit a lot of heat, so thick lead electrodes with excellent heat dissipation performance are used. In order to improve heat dissipation performance, the printed circuit board is also formed in a wide and thick way. For wiring inside the circuit board, a heat sink with a thickness of 1 mm or more is attached to the lower part of the printed circuit board and used at the same time. Therefore, if electronic components such as semiconductor wafers and lead electrode wires are heated at the same time, most of the heat is easily dissipated due to the heat dissipation performance of the electronic components, making it difficult to melt the contact portion. And the base of the substrate is fully melted and fully heated, but the temperature of electronic components such as semiconductor wafers is too high. Due to prolonged heating, the heat absorbed by the flexible printed circuit board (PCB) and the heat sink is even harmful to the surrounding electronic components. The components are heated, thereby causing failure of surrounding electronic components that are not necessary to remove and need to avoid breakage.

The problem that the invention seeks to solve

An object of the present invention is to provide an electronic component reflow and rework apparatus that stably reflows and reworks only a target electronic component to a substrate without affecting other electronic components.

Furthermore, an object of the present invention is to provide a reflow and rework apparatus for electronic components that reduces the time required to bring the electrical connection patterns such as solder balls of a target electronic component to the melting point, reduces the overall reflow and rework process time, and can Improve product yield.

Furthermore, an object of the present invention is to provide a reflow and rework apparatus that irradiates only damaged electronic components mounted on a printed circuit board with an infrared laser beam to prevent heat from being transferred to adjacent normal electronic components , and only the damaged electronic components can be removed.

Furthermore, an object of the present invention is to provide a reflow and rework apparatus which, when electronic components of different sizes are mounted on a printed circuit board, is changed by adjusting the distance between the laser beam irradiating portion and the mounted components. The laser beam irradiates the area so that electronic components of different sizes are removed individually.

Furthermore, an object of the present invention is to provide a reflow and rework apparatus that removes various types of components by using a laser beam having an area corresponding to the smallest-sized component when electronic components of different sizes are mounted on a printed circuit board. sized parts.

Furthermore, an object of the present invention is to provide a reflow and rework apparatus that, when electronic components are mounted on a printed circuit board with low infrared laser beam transmission power or excellent heat dissipation properties due to the thickness of electronic components, is The lead electrode wire around the component mainly applies the infrared laser beam, so that it does not apply too much thermal shock to the electronic component, and the electronic component can be removed from the substrate.

Furthermore, an object of the present invention is to provide a reflow and rework apparatus that only irradiates an infrared laser beam to damaged electronic components mounted on a printed circuit board, in a ball grid array (BGA, Ball Grid Array, for example) ) in the case where a plurality of solder balls are formed on the lower surface of the mounting, the time required to separate the electronic components to be removed can also be reduced.

Furthermore, an object of the present invention is to provide a reflow and rework apparatus including an infrared laser beam irradiation section and an ultraviolet irradiation section for irradiating ultraviolet rays for decomposing a resin binder, and a semiconductor wafer and solder balls are bonded together with a resin by a resin. When the adhesive is bonded to the printed circuit board, the solder balls may be melted and the resin adhesive may be decomposed to remove electronic components from the substrate.

technical means to solve problems

A reflow and rework apparatus for electronic components according to the present invention for achieving the above-mentioned technical object includes: a stage for arranging a substrate on which an electronic component to be reflowed or reworked is mounted; The area of the electronic component is heated to heat the electrical connection pattern provided on the electronic component; the laser irradiation unit heats the electrical connection pattern provided on the electronic component by irradiating the electronic component with a laser; the control command input unit, for receiving a job control command; and a control unit for operating the heating unit and the laser irradiation unit according to the job control command received by the control command input unit, so as to cause the electronic component to reflow to the substrate or to the substrate The way the electronic components are reworked by substrate reflow is controlled.

Furthermore, the present invention is characterized in that the electrical connection pattern of the electronic component is individually heated by the respective heats transferred from the heating portion and the laser irradiation portion, thereby reducing the heating time for reflow or rework, and using In the heating process of reflow or rework, damage to the surface of the above-mentioned electronic component, which is the laser irradiation surface, is prevented.

Furthermore, the present invention is characterized in that, when the operation control command is in the sequential operation mode, the control unit controls the heating unit and the laser irradiation unit to operate sequentially.

Furthermore, the present invention is characterized in that, when the operation control command is in the simultaneous operation mode, the control unit controls the heating unit and the laser irradiation unit to operate simultaneously.

Furthermore, the present invention is characterized in that, when the operation control command is in the overlapping operation mode, the control unit controls the heating unit and the laser irradiation unit to overlap operation in at least a part of the region.

Moreover, this invention is characterized in that the said heating part heats the area|region containing the said electronic component by the air convection heating method or the optical radiation heating method.

Furthermore, the present invention is characterized in that the heating unit heats the region including the electronic component by supplying hot air to the region including the electronic component.

Furthermore, the present invention is characterized in that the heating unit irradiates light including at least one of ultraviolet rays and infrared rays to the region including the electronic component to heat the region including the electronic component.

Furthermore, the present invention is characterized in that the light source supplied by the laser irradiation unit is a simultaneous irradiation surface light source that simultaneously irradiates all the places belonging to the laser irradiation area.

Furthermore, the present invention is characterized in that the light source supplied by the laser irradiation unit is a sequential irradiation surface light source that sequentially irradiates a plurality of individual places belonging to the laser irradiation area.

Furthermore, the present invention is characterized in that the light source supplied by the laser irradiation unit is a point light source, and the point light source is scanned by a high-speed mirror to obtain a surface light source irradiation effect based on the laser irradiation area.

Furthermore, the present invention is characterized in that, among the laser beams irradiated from the laser irradiation section, the optical power of the incident laser beams is partially transmitted through the electronic component to be removed to heat and melt the welding section, The said soldering part solders the said board|substrate and the said electronic component.

In addition, the present invention is characterized in that the above-mentioned laser irradiation part includes: a beam shaper, which converts the infrared laser generated from the laser oscillator and transmitted through the optical fiber into a surface light source form; an optical lens module, which makes the above-mentioned beam The shaper converts the infrared laser beam into the surface light source to irradiate the above-mentioned electronic component as the object of removal; the driving device makes the area of the above-mentioned infrared laser beam correspond to the surface area of the above-mentioned electronic component as the object of removal or is smaller than the above-mentioned electronic component The optical lens module is driven according to the surface area of the component; and a control device controls the operation of the driving device.

In addition, the present invention is characterized in that the laser beam irradiated from the laser irradiation unit has a wavelength range capable of transmitting the ethyl methyl carbonate (EMC) mold layer and the silicon wafer of the electronic component to be removed at a considerable rate.

In addition, the present invention is characterized in that the laser beam has a wavelength range of 800 nm to 1200 nm, a range of 1400 nm to 1600 nm, a range of 1800 nm to 2200 nm, and a range of 2500 nm to 3200 nm. The mold layer has a thickness of 1000 μm or less.

Furthermore, the present invention is characterized in that the laser irradiation unit controls the heating temperature of the soldering part in a range of 220°C to 260°C, and controls the surface temperature of the electronic component to be removed in a range of 300°C to 350°C or less, the irradiation time of the laser beam is controlled to be 1 millisecond or more and 30 seconds or less.

Furthermore, the present invention is characterized in that, when the substrate is a polymer material that is easily affected by high temperature, the laser irradiation unit controls the substrate temperature to be in the range of 200° C. or below, and controls the irradiation time of the laser beam to 1 millisecond. more than 30 seconds.

In addition, the present invention is characterized in that the present invention further includes a laser beam blocking cover, and the laser beam blocking cover is provided between the laser irradiation part and the electronic component to be removed, so as to remove the laser beam from the laser irradiation part. The irradiated laser beam is blocked so as not to transmit the electronic component to be removed, and the laser irradiation section irradiates a laser having an irradiation area including a lead region of the side wiring of the electronic component to be removed. beam.

In addition, the present invention is characterized in that the present invention further includes an ultraviolet irradiation unit for irradiating ultraviolet rays at various angles and directions for decomposing the resin adhesive attached to the soldered portion between the electronic component to be removed and the substrate. .

Furthermore, the present invention is characterized in that the ultraviolet irradiation part is an ultraviolet laser oscillator that generates an ultraviolet laser beam or a high output ultraviolet light emitting diode (LED) module that generates a high output ultraviolet beam.

Efficacy compared to prior art

According to the present invention, there is provided an electronic component reflow and rework apparatus that stably reflows and reworks only a target electronic component to a substrate without affecting other electronic components.

Further, according to the present invention, there is provided a reflow and rework apparatus for electronic components that reduces the time required for the electrical connection pattern of the solder balls of the target electronic component to reach the melting point, reduces the overall reflow and rework process time, and can improve product quality. rate of return.

Further, according to the present invention, there is provided a reflow and rework apparatus for electronic components in which the heating unit heats the entire electronic component and the entire substrate in the process of bringing the electrical connection pattern such as the solder balls of the target electronic component to a melting point to a specific temperature lower than the melting point, and then maintaining the temperature of the upper surface of the electronic component at a low temperature in order to either simultaneously or partially overlapped in the time domain (partially overlapped in time domain) to heat the soldered portion above the melting point, During reflow and rework, damage to electronic components can be completely removed.

Further, according to the present invention, there is provided a reflow and rework apparatus for electronic components in which, in the process of bringing the electrical connection pattern such as the solder balls of the target electronic component to the melting point, even if the absorption rate related to the laser of the electronic component is too low or If it is too high, the laser can effectively reach the solder ball, and the additional temperature rise of the laser can be adjusted, so that the reflow and rework can be performed on electronic components with various laser-related absorptivity.

Further, according to the present invention, there is provided a reflow and rework apparatus that irradiates only damaged electronic components among electronic components mounted on a printed circuit board with an infrared laser beam so that heat is not transmitted to adjacent normal electronic components, and Only damaged electronic components can be removed.

Furthermore, according to the present invention, there is provided a reflow and rework apparatus that changes the laser beam by adjusting the distance between the laser beam irradiating portion and the mounted component when electronic components of different sizes are mounted on a printed circuit board. The beam irradiates the area so that electronic components of different sizes are removed individually.

Furthermore, according to the present invention, there is provided a reflow and rework apparatus that removes various sizes of electronic components by using a laser beam having an area corresponding to the smallest size component when electronic components of different sizes are mounted on a printed circuit board. part.

In addition, according to the present invention, there is provided a reflow and rework apparatus which is capable of mounting electronic components on a printed circuit board having a small infrared laser beam transmission power or excellent heat dissipation due to the thickness of the electronic components. The lead electrode wire around the component mainly applies an infrared laser beam, so that it does not apply too much thermal shock to the electronic component, and the electronic component can be removed from the substrate.

Furthermore, according to the present invention, there is provided a reflow and rework apparatus that irradiates only damaged electronic components among electronic components mounted on a printed circuit board with an infrared laser beam, and irradiates an infrared laser beam in a device such as a Ball Grid Array (BGA). Even when a plurality of solder balls are formed on the lower surface of the mounting, the time required to separate the electronic components to be removed can be reduced.

Further, according to the present invention, there is provided a reflow and rework apparatus including an infrared laser beam irradiation unit and an ultraviolet irradiation unit for irradiating an ultraviolet ray for decomposing a resin adhesive, and wherein the resin adhesive is used together with the semiconductor wafer and the solder balls. In the case of bonding to a printed circuit board, the solder balls may be melted to decompose the resin adhesive to remove electronic components from the board.

For the embodiments according to the inventive concept disclosed in this specification, the specific structural or functional descriptions are only used to illustrate the embodiments according to the inventive concept, and the embodiments according to the inventive concept can be implemented in various forms, The embodiments described in this specification are not limited thereto.

Embodiments according to the concepts of the present invention can be variously modified and have various forms, and therefore, the embodiments are illustrated in the drawings and described in detail in this specification. However, the embodiment based on the concept of the present invention is not limited to a specific disclosed form, and includes all modifications, equivalent technical solutions, or alternative technical solutions included in the idea and technical scope of the present invention.

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

2 is a functional block diagram of a reflow and rework apparatus for electronic components according to an embodiment of the present invention, and FIG. 3 is a diagram showing an exemplary structure of an electronic component reflow and rework apparatus according to an embodiment of the present invention.

2 and 3 , a reflow and rework apparatus for electronic components according to an embodiment of the present invention includes a worktable 10 , a heating unit 20 , a laser irradiation unit 30 , a control command input unit 40 and a control unit 50 .

A stage 10 (stage) is a component for arranging the substrate 3 , and the electronic component 1 to be reflowed or reworked is mounted on the substrate 3 . For example, the board 3 may be a printed circuit board, and the printed circuit board may be provided with a plurality of pads for electrical connection with the electronic component 1 . The electronic component 1 may be any component mounted on a printed circuit board including an integrated circuit chip (IC), a manual component, or the like, and the electronic component 1 is provided with electrical contacts with a plurality of pads provided on a substrate 3 such as a printed circuit board. Connected electrical connection pattern 2. For example, the electrical connection patterns 2 provided in the electronic component 1 may be solder balls, but not limited to this, and may be any units such as leads that can be electrically connected to the substrate 3 . On the other hand, for example, the table 10 for arranging the substrate 3 may be a mechanically added component, but it is not limited to this, and may also refer to a conventional bottom surface instead of a mechanically added component.

The heating unit 20 heats the electrical connection pattern 2 provided on the electronic component 1 by heating the region including the electronic component 1 mounted on the substrate 3 . For example, the heating part 20 can heat the area|region containing the electronic component 1 by the air convection heating method or the optical radiation heating method.

As a specific example, the heating unit 20 may supply hot air to the area including the electronic component 1 to heat the area including the electronic component 1 . As another specific example, the heating unit 20 may irradiate ultraviolet rays, infrared rays, or light including ultraviolet rays and infrared rays to the area including the electronic component 1 to heat the area including the electronic component 1 . In the following content, this will be explained in detail through another embodiment.

The laser irradiation unit 30 heats the electrical connection pattern 2 provided in the electronic component 1 by irradiating the electronic component 1 with a laser.

For example, the light source supplied by the laser irradiation unit 30 may be a simultaneous irradiation surface light source that simultaneously irradiates all the places belonging to the laser irradiation area. As another example, the light source supplied by the laser irradiation unit 30 may be a sequentially irradiated surface light source that sequentially irradiates a plurality of individual places belonging to the laser irradiation area. As another example, the light source supplied by the laser irradiation unit 30 is actually a point light source, and the above-mentioned point light source can obtain the irradiation effect of the surface light source based on the laser irradiation area by high-speed mirror scanning or driving of the lower stage.

The control command input unit 40 is a structural element for receiving operation control commands, and the operation control commands can be input by an operator or automatically according to a preset operation program. In other figures below, the illustration of the control command input unit 40 and the related description will be omitted.

The control unit 50 operates the heating unit 20 and the laser irradiation unit 30 according to the operation control command received by the control command input unit 40 to reflow the electronic component 1 to the substrate 3 (or reflow soldering, soldering, bonding) or to the substrate 3 . 3 The reflowed electronic component 1 is reworked (or debonded, separated, released).

According to the control of the control unit 50 , the electrical connection patterns 2 of the electronic component 1 are individually heated or overlapped by the heat transferred from the heating unit 20 and the laser irradiation unit 30 , 1) thereby reducing the need for reflow or rework , 2) prevent damage to the surface of the electronic component 1 as the first irradiated surface of the laser during the heating process for reflow or rework, 3) do not affect other than the target electronic component for reflow or rework Other electronic components and only the target electronic components are stably reflowed or reworked to the substrate 3 .

A specific and exemplary control operation of the control section 50 is described below.

First, when the operation control command is in the sequential operation mode, the control unit 50 can make the heating unit 20 and the laser irradiation unit 30 operate sequentially instead of simultaneously operating at the same time. As a specific example, 1) the control unit 50 operates the heating unit 20 to heat the target electronic component and its surrounding area, and after heating the electrical connection pattern 2 provided on the electronic component to a temperature before the melting point, 2) causes the heating The part 20 is stopped, and the laser irradiation part 30 is operated so that the electrical connection pattern 2 provided in the target electronic component reaches the melting point.

Second, when the operation control command is in the simultaneous operation mode, the control unit 50 can make the heating unit 20 and the laser irradiation unit 30 operate simultaneously in time. According to this, 1) although the temperature of the target electronic component and its surrounding area is increased by the heat supplied by the heating unit 20 , the electrical connection pattern 2 cannot reach the melting point. 2) At the same time, the laser heating section 20 irradiates the target electronic component with laser light, therefore, the electrical connection pattern 2 provided on the target transfer element reaches the melting point, but the laser is not provided on the electronic components located around the target electronic component Therefore, the electrical connection patterns provided on the surrounding electronic components cannot reach the melting point.

Third, when the operation control command is in the overlapping operation mode, the control unit 50 can operate the heating unit 20 and the laser irradiation unit 30 to overlap at least a part of the time area. As a specific example, 1) the control unit 50 operates only the heating unit 20 for the first time to increase the temperature of the target electronic component and its surrounding area, and then 2) causes the heating unit 20 and the laser irradiation unit 30 to operate at the first time. The temperature of the target electronic component is higher than the surrounding area by working for two time, so that the electrical connection pattern 2 provided on the target electronic component reaches the melting point.

4 is a structural diagram of a laser irradiation part of an electronic component reflow and rework apparatus according to an embodiment of the present invention.

As shown in FIG. 4 , the present invention includes an infrared laser irradiation unit 120 . The infrared laser irradiation unit 120 includes a power supply unit 110 for power supply and a laser oscillator 121 for generating an infrared laser beam.

The infrared laser beam irradiated from the laser irradiation unit 120 transmits the electronic component to be removed, and heats and fuses the soldering portion that solders the substrate and the electronic component. The solder portion means a joint portion formed by solder balls, solder bumps, etc. and passed through solder paste (SOLDER PASTE).

The infrared laser beam irradiated from the infrared laser beam irradiating part 120 transmits the methyl ethyl carbonate mold layer and the silicon wafer of the electronic component to irradiate the solder balls, and for this reason, it can effectively transmit the infrared wavelength range of the methyl ethyl carbonate mold layer, For example, "800 nm to 1200 nm" or "1400 nm to 1600 nm" or "1800 nm to 2200 nm" or "2500 nm to 3200 nm". A part of the laser beam does not transmit through the methyl ethyl carbonate mold layer according to the transmittance of each wavelength of the laser beam, and heats the surface thereof to transfer heat to the soldering part of the lower part of the electronic component.

In the case of a conventional semiconductor wafer, the thickness of the ethyl methyl carbonate mold layer is several millimeters or more, so the transmission amount of the infrared laser beam passing through the semiconductor wafer is small, but the thickness of the ethyl methyl carbonate mold layer of the recent semiconductor wafer has Very thin, below 1000μm to 600μm is called mainstream products. Therefore, in the case of a semiconductor wafer provided with the above-mentioned thin-film ethyl methyl carbonate mold layer, the transmission amount of the infrared laser beam of the present invention can be sufficiently transmitted to the solder balls arranged in the bonding portion of the lower portion of the semiconductor wafer. It is heated and melted into a liquid state. In addition, the laser beam transmittance of silicon, which is the main material of the semiconductor wafer, also increases sharply in the infrared wavelength range, and the laser beam transmittance increases sharply with the increase of the infrared wavelength. Therefore, when the silicon wafer is irradiated with the infrared rays of the present invention In the case of a laser beam, excellent transmittance can be confirmed.

FIG. 5 is a schematic working diagram of the laser irradiation part of the reflow and rework apparatus for electronic components according to an embodiment of the present invention.

As shown in FIGS. 4 and 5 , as an example, the infrared laser beam irradiation unit 120 includes a beam shaper 122 , which generates infrared laser beams in the form of spots generated from the laser oscillator 121 and transmitted through the optical fiber 100 . The optical lens module 123 irradiates the infrared laser beam converted into the surface light source form to the electronic component as the removal object; the driving device 124 makes the infrared laser beam output from the laser oscillator 121 The optical lens module 123 is driven in such a way that the area corresponds to or is smaller than the surface area of the electronic component to be removed; and a control device (not shown) controls the operation of the driving device 124 . The control device may also be used to control components of the laser beam irradiation section other than the driving device 124 , in which case, its functions are incorporated in the control section 50 .

For example, a beam shaper 122 converts a laser beam of Gaussian shape into a surface light source with a uniform energy distribution in cross section. The beam shaper 122 may include the optical fiber 100 and a Square Light Pipe for forming a uniform quadrilateral laser. Alternatively, the beam shaper can also be a diffractive optical element (Diffractive Optical Element) type or a refractive optical element (Refractive Optical Element) type that is not a diffractive optical element, or a microlens array (Microlens array) in which a plurality of microlenses are arranged on the incident surface or the exit surface. Lens Array) type, etc.

On the other hand, the control unit 50 may control the driving device 124 so that the area of the infrared laser beam irradiated through the optical lens module 123 corresponds to the surface area of the electronic component having the smallest surface area among the plurality of electronic components 141 to be removed. or smaller than the surface area of the electronic component 141 .

According to the embodiment, the user can manually control the driving device 124, and in this case, it can also be adjusted arbitrarily, so that the area of the infrared laser beam irradiated through the optical lens module 123 and the plurality of electronic components 141 as removal objects are The surface area of the electronic component with the smallest surface area corresponds to or is smaller than the surface area of the electronic component 141 .

As described above, it is possible to minimize the phenomenon that the heat of the laser beam is applied to other electronic components located adjacent to the substrate 140 or to normal electronic components by minimizing the area of the laser beam, whereby only the Remove the electronic parts of the object.

In addition, when the area of the infrared laser beam is smaller than the surface area of the electronic component 141, if a part of the electronic component is heated by the laser beam irradiated on the electronic component, the heat will spread from the above-mentioned part of the area to other areas of the electronic component Therefore, in addition to the irradiation area of the laser beam, the remaining area of the electronic component that needs to be desoldered (De-soldering) or de-bonded (De-boding) can also be melted.

Depending on the situation, a plurality of elements are arranged around the semiconductor wafer. For example, capacitors with a size of 200 μm × 100 μm or capacitors with a size of 1004 (1000 μm × 400 μm) are arranged at a high density at very narrow intervals, and the damaged one is to be removed. In the case of capacitors, if the area of the laser beam is changed according to the size of the target element, an optical instrument that can change the cross-sectional area of the laser beam is required. Therefore, the overall price of the device increases considerably.

Therefore, when using a variable optical lens module, instead of avoiding the trouble of continuously replacing the lens for installation, a fixed optical lens module is used to make the cross-sectional area of the laser beam according to the area of the smallest electronic component and the surface area is slightly larger than the smallest The electronic components of the electronic components utilize the thermal conduction of the irradiated heat formed by the laser beam, so that the small components can be removed without changing the lens.

For example, the optical lens module 123 in this manner is composed of at least one fixed lens, and the control unit 50 controls the driving device 124 in such a way that the optical lens module 123 moves along the direction of the optical axis irradiated by the infrared laser beam, so as to adjust the The area when the infrared laser beam irradiated by the optical lens module 123 reaches the electronic component.

In order to arrange a plurality of lenses of different magnifications, at least one fixed lens is arranged in a regular annular array (eg, cylindrical) on the lens plate, so that the lenses of different magnifications can be applied according to the manual operation of the user.

The combination structure of the optical lens module 123 having the fixed lens structure as described above and the driving device 124 for driving the optical lens module 123 linearly is simple as a whole, so the possibility of failure is low and the method for realizing the present invention can be fully performed. Purpose required area adjustment function.

FIG. 6 is an exemplary structural diagram of an optical lens module of a laser irradiation part of an electronic component reflow and rework apparatus according to an embodiment of the present invention.

The device shown in FIG. 6 employs a variable optical lens module 123 having a plurality of lenses. The control unit 50 controls the driving device 124 so that the optical lens module 123 composed of a plurality of lenses moves along the direction of the optical axis irradiated by the infrared laser beam, thereby adjusting the infrared laser beam irradiated by the optical lens module 123 cross-sectional area.

For example, in the optical lens module 123, a plurality of lenses are installed in a spaced manner inside a predetermined lens barrel, and the driving device 124 makes the plurality of lens modules rise or fall independently to change the area and illumination of the surface light source scope. As described above, compared with the case where a fixed lens is provided, the optical lens module 123 provided with a plurality of lenses can easily adjust the shape and area of the surface light source, thereby enabling precise control.

6 , the plurality of lenses constituting the optical lens module 123 include a convex lens 1231 , a first cylindrical lens 1232 , a second cylindrical lens 1233 and a focusing lens 1234 . A plurality of lenses are located on the exit side of the beam shaper 122 to adjust the size and shape of the irradiated area of the laser. At this time, the first cylindrical lens and the second cylindrical lens are arranged so that the focusing direction is perpendicular, and the respective lenses adjust the beam size in the directions perpendicular to each other, thereby forming beams of various rectangular shapes.

First, the convex lens 1231 may be disposed adjacent to the exit side of the beam shaper 122 for uniformizing the laser light, so as to condense the surface-irradiated laser light. When passing through the exit side of the beam shaper 122, the laser light may diverge to spread. Therefore, the convex lens 1231 condenses light in such a way that the uniform light beam cannot be diverged, and can transmit the condensed laser beam to the first cylindrical lens 1232 . The first irradiated area A1 can be formed by laser through the convex lens 1231 .

The first cylindrical lens 1232 can adjust the length in the first axis direction of the laser beam passing through the convex lens 1231 . The first cylindrical lens 1232 can be provided in a shape cut along the vertical axis in a state where the cylinder is standing, the first cylindrical lens 1232 is provided at the lower part of the convex lens 1231, and the convex surface of the first cylindrical lens 1232 can be arranged so that the convex surface faces upward. . The irradiation area of the laser beam transmitted through the first cylindrical lens 1232 can be set so as to reduce the length in the first axis direction. Since the length of the irradiation area in the first axis direction is reduced, the irradiation area of the laser transmitted through the first cylindrical lens 1232 can be changed from the first irradiation area A1 to the second irradiation area A2.

The second cylindrical lens 1233 can adjust the length in the second axial direction of the laser beam passing through the first cylindrical lens 1232 . The length in the second axis direction and the length in the first axis direction are orthogonal to each other, and the second cylindrical lens 1233 may have the same shape as the first cylindrical lens 1232 . The second cylindrical lens 1233 is provided at the lower part of the first cylindrical lens 1232 , and is disposed so that the convex surface faces upward, and can be disposed so that the direction is orthogonal to the first cylindrical lens 1232 . The irradiation area of the laser transmitted through the second cylindrical lens 1233 can reduce the length in the second axis direction. Since the length of the irradiation area in the second axis direction is reduced, the irradiation area of the laser transmitted through the second cylindrical lens 1233 can be changed from the second irradiation area A2 to the third irradiation area A3.

The first cylindrical lens 1232 and the second cylindrical lens 1233 can easily adjust the shape of the irradiation area of the laser. The first cylindrical lens 1232 and the second cylindrical lens 1233 may be included as long as the structures can easily adjust the length in the first axis direction and the length in the second axis direction of the irradiation area of the laser. The first cylindrical lens 1232 and the second cylindrical lens 1233 can be arranged so that the convex surface faces downward, and the lens whose upper surface is concave can also be arranged at the positions of the first cylindrical lens 1232 and the second cylindrical lens 1233 . The irradiation area of the laser can be adjusted so that the length in the first axial direction and the length in the second axial direction are extended. The first cylindrical lens 1232 and the second cylindrical lens 1233 can be included in one embodiment as long as the ratio of the horizontal and vertical lengths of the irradiation area can be adjusted by adjusting the first axial length and the second axial length of the laser irradiation area.

The positions of the first cylindrical lens 1232 and the second cylindrical lens 1233 are interchangeable. That is, the laser beam transmitted through the convex lens 1231 is preferentially transmitted through the second cylindrical lens 1233 over the first cylindrical lens 1232 to adjust the second axial length of the irradiation area, and then the first axial length is adjusted.

The focusing lens 1234 can make the irradiation area of the laser beam passing through the first cylindrical lens 1232 and the second cylindrical lens 1233 have a preset width. The focusing lens 1234 maintains the shape of the irradiated area formed by the second cylindrical lens 1233, and can increase or decrease the width of the irradiated area. The focusing lens 1234 can increase or decrease the width of the irradiation area while maintaining the shape by the ratio of the length in the first axis direction to the length in the second axis direction of the irradiation area formed by the second cylindrical lens 1233 . The third irradiation area A3 , which is the irradiation area of the laser transmitted through the second cylindrical lens 1233 , can be enlarged by the focusing lens 1234 to have the width of the fourth irradiation area A4 . The focusing lens 1234 can also reduce the width of the third illumination area A3. The focusing lens 1234 can be provided in a replaceable manner.

7 is a graph showing the surface temperature of a semiconductor wafer that absorbs an infrared laser beam irradiated from a laser irradiation unit of an electronic component reflow and rework apparatus according to an embodiment of the present invention.

According to the detection results of the present inventors, when the temperature of the solder layer absorbs the laser beam in the range of 220°C to 260°C higher than the melting point and heats it, the surface temperature of the semiconductor wafer can be made to be about 300°C to 350°C range of control. The solder can be melted by irradiating an infrared laser beam without affecting the semiconductor wafer within about 1 millisecond or more and within 30 seconds.

Embodiment of the invention

FIG. 8 is a working schematic diagram of a reflow and rework apparatus for electronic components according to still another embodiment of the present invention.

Electronic components such as semiconductor wafers with a thickness of 1000 μm or more or electrical components of power transistors emit a lot of heat. Therefore, thick lead electrode wires with excellent heat dissipation performance are often wired on the side surfaces. In this case, Usually, a printed circuit board with excellent heat dissipation performance is used together with an additional heat dissipation plate attached to the lower part of the printed circuit board. Therefore, when such electronic components are irradiated with a laser beam, most of the heat is released, and therefore, in order to melt the lead electrode wire, that is, the solder paste of the lead wire, excessive laser irradiation and the resulting electrons are required. The temperature of the parts rises too much, etc.

The reflow and rework apparatus of the embodiment shown in FIG. 8 is suitable for the above-mentioned situation, is provided between the laser irradiation unit 30 and the electronic component to be removed, and includes an infrared laser irradiated from the laser irradiation unit 30 . The laser beam shielding cover 210 that shields the electronic components to be removed cannot pass through the beam.

The laser irradiation unit 30 irradiates a laser beam of an area corresponding to the area including the area of the side lead 4 of the electronic component 1 soldered on the substrate 3 to be removed.

The laser beam blocking cover 210 for selectively blocking and transmitting the laser beam includes an opening portion 211 for transmitting the infrared laser beam and a blocking portion 212 for blocking the infrared laser beam, and the blocking portion 212 is used for blocking the electronic components. 1. The irradiated infrared laser beam passes through the opening portion 211 so that the infrared laser beam is irradiated to the lead wire 4, so that the lead wire 4 is attached to the substrate 3 and the solder is melted.

FIG. 9 is a schematic working diagram of a reflow and rework apparatus for electronic components according to another embodiment of the present invention.

When the electronic component 1 such as a semiconductor wafer is bonded and fixed to the substrate 3 with a solder ball (SODLER BALL) 4 and a resin adhesive 5 , in order to melt the solder ball 4 , the laser irradiation unit 30 is irradiated with an infrared laser beam. , the resin adhesive 5 is further tightened by carbonization by the heat of the laser beam, so even if the solder balls 4 are melted, it is difficult to remove the electronic component 1 due to the tightened resin adhesive 5 .

Therefore, the solder balls 2 are melted and removed by heating the solder balls 2 with an infrared laser beam, and at the same time, if the resin adhesive 5 is a polymer compound, the ultraviolet irradiation unit 510 is used to irradiate the resin adhesive 5 with an ultraviolet laser beam. , the ultraviolet rays can cut the polymer link chain of the resin adhesive 5 to decompose the resin adhesive 5 in a non-thermal manner.

The ultraviolet irradiation section 22 can be realized by an ultraviolet laser oscillator that generates an ultraviolet laser beam or a high-output ultraviolet light-emitting diode module that generates a high-output ultraviolet laser beam. The irradiation smoothly removes the electronic component 1 soldered on the substrate 3 with the solder balls 2 and the resin adhesive 5 .

In this case, the ultraviolet irradiation unit 22 can be used as an energy source instead of hot air for heating, and an additional heating unit can be used to preheat the substrate 3 and the electronic component 1 simultaneously, sequentially or overlappingly. Light beams and UV exposure.

In the above, the present invention described by various embodiments is not limited to the above-mentioned embodiments and the accompanying drawings, and various substitutions, modifications and changes can be made within the scope of the technical matters of the present invention. The staff is clear. Therefore, the true technical protection scope of the present invention needs to be defined by the protection scope of the invention claimed.

A: Electronic parts B: Electronic components C: Electronic components 1: Electronic components 2: Electrical connection pattern 3: Substrate 4: Solder balls 5: Resin binder 10: Workbench 20: Heating part 22: UV irradiation part 30: Laser irradiation section 40: Control command input part 50: Control Department 100: Optical fiber 110: Power Supply Department 121: Laser oscillator 122: Beam Shaper 123: Optical lens module 124: Drive 140: Substrate 141: Electronic Components 1231: Convex Lens 1232: The first cylindrical lens 1233: Second Cylindrical Lens 1234: Focusing Lens A1: The first irradiation area A2: Second irradiation area A3: The third irradiation area A4: Fourth irradiation area 210: Laser beam blocking cover 211: Open Ministry 212: Barrier

FIG. 1 is a diagram for explaining a conventional method of reflow and rework using hot air; 2 is a functional block diagram of a device for reflowing and reworking electronic components according to an embodiment of the present invention; 3 is an exemplary structural diagram of a reflow and rework apparatus for electronic components according to an embodiment of the present invention; 4 is a structural diagram of a laser irradiation part of a reflow and rework device for electronic components according to an embodiment of the present invention; 5 is a working schematic diagram of a laser irradiation unit used in the reflow and rework apparatus for electronic components according to an embodiment of the present invention; 6 is a structural diagram of an optical lens module of a laser irradiation portion used in the reflow and rework apparatus for electronic components according to an embodiment of the present invention; 7 is a surface temperature curve diagram of a semiconductor wafer that absorbs an infrared laser beam irradiated in a laser irradiation part of a reflow and rework device for electronic components according to an embodiment of the present invention; 8 is a working schematic diagram of a reflow and rework device for electronic components according to still another embodiment of the present invention; FIG. 9 is a working diagram of a reflow and rework apparatus for electronic components according to another embodiment of the present invention.

20: Heating part

30: Laser irradiation section

40: Control command input part

50: Control Department

Claims (17)

A reflow and rework apparatus for electronic components, comprising: a stage for arranging a substrate on which electronic components to be reflowed or reworked are mounted; and a heating unit for heating a region including the electronic components The electrical connection pattern provided on the electronic component is heated; the laser irradiation unit heats the electrical connection pattern provided on the electronic component by irradiating the electronic component with a laser; the control command input unit is used for receiving operation control commands and a control unit that operates the heating unit and the laser irradiating unit according to the operation control command received by the control command input unit, so that the electronic components are reflowed to the substrate or the electronic components that are reflowed to the substrate are operated. The control is performed in a rework manner. When the operation control command is in the sequential operation mode, the control unit controls the heating unit and the laser irradiation unit to operate in sequence, and the operation control command is in the simultaneous operation mode. In the case of the control unit, the control unit controls the heating unit and the laser irradiation unit to operate simultaneously, and when the operation control command is in the overlapping operation mode, the control unit controls the heating unit and the laser beam to operate simultaneously. The radiation irradiation unit is controlled so that the operation is overlapped in at least a part of the region. The reflow and rework apparatus for electronic components according to claim 1, wherein the electrical connection patterns of the electronic components are formed by the respective heat transferred from the heating unit and the laser irradiation unit. It is heated separately, thereby reducing the heating time for reflow or rework, and preventing damage to the surface of the above-mentioned electronic component as the laser irradiation surface during the heating process for reflow or rework. The reflow and rework apparatus for electronic components according to claim 1, wherein the heating unit heats the region including the electronic components by air convection heating or optical radiation heating. The reflow and rework apparatus for electronic components according to claim 3, wherein the heating unit heats the area including the electronic component by supplying hot air to the area including the electronic component. The reflow and rework apparatus for electronic components according to claim 3, wherein the heating unit irradiates light including at least one of ultraviolet rays or infrared rays to the area including the electronic component to heat the area including the electronic component. The reflow and rework apparatus for electronic components according to claim 1, wherein the light source supplied by the laser irradiation unit is a simultaneous irradiation surface light source that simultaneously irradiates all places belonging to the laser irradiation area. The reflow and rework apparatus for electronic components according to claim 1, wherein the light source supplied by the laser irradiation unit is a sequentially irradiated surface light source that sequentially irradiates a plurality of individual places belonging to the laser irradiation area. The reflow and rework apparatus for electronic components according to claim 1, wherein the light source supplied by the laser irradiation unit is a point light source, and the point light source is scanned by a high-speed mirror to obtain a surface light source irradiation effect based on the laser irradiation area. The reflow and rework apparatus for electronic components according to claim 1, wherein the optical power of the incident laser beam partially transmits the electronic component to be removed from the laser beam irradiated by the above-mentioned laser irradiating section, and the welding is performed. The soldering portion is heated and melted, and the soldering portion solders the substrate and the electronic component. The device for reflow and rework of electronic components according to claim 1, wherein the laser irradiation unit comprises: a beam shaper, which converts the infrared laser generated from the laser oscillator and transmitted through the optical fiber into a surface light source form; an optical lens module, so that the infrared laser beam converted into a surface light source by the beam shaper is irradiated to the above-mentioned electronic component as the object of removal; the driving device is to make the area of the infrared laser beam as the object of removal and the above-mentioned electronic component to be removed The optical lens module is driven in such a way that the surface area of the component corresponds to or is smaller than the surface area of the electronic component; and a control device controls the operation of the drive device. The reflow and rework apparatus for electronic components according to claim 1, wherein the laser beam irradiated from the laser irradiation unit has a methyl ethyl carbonate mold layer and a silicon wafer that can transmit the electronic components to be removed at a considerable rate wavelength range. The reflow and rework apparatus for electronic components according to claim 11, wherein the laser beam has a wavelength range of 800 nm to 1200 nm, 1400 nm to 1600 nm, 1800 nm to 2200 nm, and 2500 nm to 3200 nm. The methyl ethyl carbonate mold layer of the electronic component has a thickness of 1000 μm or less. The reflow and rework apparatus for electronic components according to claim 14, wherein the laser irradiation section controls the heating temperature of the soldering section within a range of 220°C to 260°C, and controls the surface temperature of the electronic components to be removed at In the range of 300°C to 350°C or below, the irradiation time of the laser beam is controlled to be 1 millisecond or more and 30 seconds or less. The reflow and rework apparatus for electronic components according to claim 11, wherein, when the substrate is a polymer material susceptible to high temperature, the laser irradiation unit controls the temperature of the substrate to be in the range of 200°C or below, and the laser beam The irradiation time is controlled to be more than 1 millisecond and less than 30 seconds. The reflow and rework apparatus for electronic components according to claim 1, further comprising a laser beam blocking cover, wherein the laser beam blocking cover is provided between the laser irradiation part and the electronic component to be removed, so as to remove the laser beam from the laser beam. The laser beam irradiated by the laser irradiating part is blocked so as not to transmit the electronic component to be removed, and the laser irradiated part irradiates the area including the lead wires having wiring on the side surface of the electronic component to be removed. The laser beam on the irradiated area. The reflow and rework apparatus for electronic components according to claim 1, further comprising: irradiating at various angles and directions for decomposing the resin adhesive attached to the soldered portion between the electronic component to be removed and the substrate Ultraviolet ray irradiation part. The reflow and rework apparatus for electronic components according to claim 16, wherein the ultraviolet irradiation unit is an ultraviolet laser oscillator that generates an ultraviolet laser beam or a high output ultraviolet light emitting diode module that generates a high output ultraviolet beam.

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