KR20160067230A - An light aligning method of an optical device and an optical fiber for an optical module. - Google Patents

Abstract

The present invention relates to an optical axis aligning method of an optical module comprising: a light transmission module (100); an optical device (200); a substrate (210); an electrode pad (220); and an optical block having a light transmission member mounting unit. The optical axis aligning method comprises the steps of: mounting the substrate on which the optical device is mounted at a certain point and determining the light input and output point of the optical device; and locating a central axis of the light transmission member mounting unit on the determined light input and output point. Additionally, the step of locating a central axis of the light transmission member mounting unit on the determined light input and output point comprises the steps of: preparing an optical block; placing the optical block on the substrate while covering the optical device; repeating the process of measuring light transmission efficiency while converting and moving the position of the optical block (300) on the substrate, until a first position of the optical block on the substrate to make the light transmission efficiency satisfy a certain condition is searched; and fixating the optical block (300) on the first position. Here, the step of locating a central axis of the light transmission member mounting unit on the determined light input and output point may include a step of directly molding the optical block on the substrate in a 3D printing method.

Description

A method of aligning an optical axis between an optical element of an optical module and an optical transmission member.

The present invention relates to a method for modularizing an optical device including an optical device and an optical transmission member for high-speed transfer of large-capacity data or high-capacity data between devices in the device, wherein the optical axis alignment between the optical device and the optical transmission member is completed within the module, The present invention relates to an optical axis alignment of an optical module capable of eliminating an optical axis misalignment that may occur when an optical axis is misaligned, To an optical axis alignment.

Recently, high-speed, high-speed data transmission technology such as high image quality and 3D image contents is emerging in the device or between devices, and signal attenuation, noise, EMI / EMC, impedance matching, cross talk, skew,

Generally, in data transmission between devices or between devices, that is, electrical leads based on copper wiring are used in the device, and cables using the same are used between devices. However, copper wiring does not satisfy high-capacity data high-speed transmission needs , And the various technical issues mentioned above are not resolved.

Recently, optical connection technology has been researched and developed to solve this problem. The optical module replaces several tens of channels of parallel electrical signal lines with serial optical signal lines, enabling high-speed data transmission at high speeds and eliminating technical problems such as noise, EMI / EMC, impedance matching, cross talk, skew, .

Many kinds of optical connectors and optical modules are being developed to apply optical transmission and optical connection devices using optical materials to various use environments. They basically provide a connecting function for connecting two or more separated light pathways and also form and change optical signal transmission paths by using optical phenomena such as refraction, reflection, interference and diffraction, A function of amplifying or merging an optical signal, and the like. The optical element having such a configuration functions to connect two different regions-optical region and electric region, or to connect the optical region and the optical region, and at the same time, to design an optimal transmission efficiency to provide. The problems are inherent in the components included in the optical connector system and the like. For example, in a device (a die bonder, etc.) for mounting an optical element on a substrate, errors are inherently inevitably, and the final mounting position of the optical element is indefinite. Even in the case of an optical transmission member, Error occurs.

In order to solve the above-mentioned problem, a process of active optical alignment has been developed. Active optical axis alignment refers to a series of arrangements in which elements for optical signal transmission, such as optical elements, are optimally arranged or arranged so as to search for and find a point or state for optimal optical transmission efficiency, and to fix such point or state Process. However, since the alignment of the active optical axis is time-consuming for the operation process and is not suitable for mass production, recently, it has been attempted to align the optical axis by designing and arranging the structural elements inside the connector, or to manually position the optical elements directly on the optical path The optical axis alignment method is spreading.

In addition, as the size of electronic devices is reduced, there is a problem of miniaturization and low reduction in the optical devices such as the optical connectors used therein. Therefore, it is necessary to optimize the existing layout for the elements inside the device to meet these requirements, It is becoming important to devise.

The optical module of FIG. 1 (hereinafter referred to as "prior art 1") comprises a transmitter 10a, a receiver 10b, and an optical transmission line 2 as a connection wiring between a transmitter and a receiver. The transmitting section is composed of a VCSEL chip 3a on the substrate 6a, an electrode pad 5a, a bonding wire 7a, a liquid resin 8a and a height supporting member 4a. An electrode pad 5b, a bonding wire 7b, a liquid resin 8b and a height supporting member 4b.

1, an electrical signal from a board connected to a transmitter is controlled by a driver IC (not shown) through an electrode pad 5a on a substrate 6a, and the VCSEL chip 3a receives an optical signal And is reflected on a 45-degree mirror surface formed at the end of the optical path 2 to change its path, and then is transmitted to the receiving part through the optical path 2. [

The light is reflected by the 45 ° mirror surface formed at the end of the optical path 2 and is then incident on the PD chip 3b on the substrate 6b, Is converted into an electric signal in the PD chip 3b through the control of [not shown] and input to the board connected to the receiving unit.

The optical-electrical-composite-type connector shown in Fig. 2 is disclosed in Japanese Unexamined Patent Publication No. 2010-266729 (entitled " photoelectric hybrid-type connector " same. 2 shows a plug 20 which is fastened to a connector 30 called a receptacle mounted on an in-device board. The plug 20 includes a housing 21, A ground plate 24 mounted on the inner bottom surface of the housing 21 and an electric terminal 22 and a ground terminal 23 mounted on both sides of the ground plate 21, The bonding wires 28 of the connection wiring function between the VCSEL chip 26, the Driver IC 27, the electric terminal 22 and the ground terminal 23 on the VCSEL chip 26 and the Driver IC 27 on the VCSEL chip 26, And an optical fiber 29 inserted into the housing 21.

3 shows a 45 ° light reflection surface that accommodates the PCB substrate 50 and the optical transmission member 80 on which the optical device 40 is mounted and functions to deflect the optical signal at right angles, An optical sub-assembly (OSA) 70 made of a light-transmissive material having a lens unit for condensing the light, a guide member 90 for fixing the optical transmission member to the OSA, and a high- And an optical axis aligning member (60) for aligning the optical axis for transmitting the optical signal from the optical element to the optical transmission member at a high transmission efficiency. The optical axis alignment member (60) The alignment of the optical axis is performed by the engagement of the alignment protrusions 71 and the alignment groove portions 61 formed in the substrate 60 and the OSA 70, respectively.

JP 2010-266729 A

The conventional art 1 requires not only an additional machining process for cutting the end surface of the light transmitting member so that the end surface of the light transmitting member forms 45 degrees with respect to the axial direction but also the die bonder die used for mounting the optical device on the circuit board the active optical alignment process must be included to compensate for the equipment errors inherently present in the bonder. In the optical axis alignment process in the prior art 1, the transmission efficiency is measured by using a measuring device such as an optical spectrum analyzer for an optical signal generated after the driving circuit of the optical device is operated, And sequentially fixing the optical element and the optical transmission member to the position in the state. However, through such active optical axis alignment, although a certain level of optical transmission efficiency is guaranteed, there is a problem that it is relatively time-consuming and costly because it is basically based on a trial and error technique.

On the other hand, in the prior art 2, the driver IC 27 on the ground plate 24 and the electric terminal 22 on the side of the housing 21 must be electrically connected by a wire bonding process. It is difficult to realize the bonding wires 28 on the terminals 22 and 20, and in particular, when the number of pins of the electrical terminals 22 increases, the wire bonding process becomes complicated. In the prior art 2, since all the elements and components must be mounted inside the small-sized plug housing 20, the driver IC 27 having a relatively high process degree and a relatively large size is located on the plug side , There is a problem that miniaturization of the plug may be difficult.

In the prior art 2, the VCSEL chip 26 is mounted on the submount 25 made of a wafer and mounted on the ground plate 24, the optical fiber 29 is placed on the ground plate 24 to form the VCSEL chip 26, And the VCSEL chip 26 and the optical fiber 29 are not fixed relative to each other, so that the optical alignment can not be properly performed. In addition, there is a problem that the plug 20 is difficult to operate because there is no part that can be held by hand by fastening (plugging) the plug 20 to the receptacle 30 or detaching (removing) the plug 20 from the receptacle 30.

In the prior art 3, errors that can be considered in relation to the alignment of the optical axes include errors between the PCB substrate 50 and the optical axis alignment member 60, between the optical axis alignment member 60 and the OSA 70, 80 and the OSA 70 are accumulated. More specifically, in the mounting of the optical axis alignment member 60 on the PCB substrate 50, the optical element 40 is placed on the connection line of the center of the end face of the alignment groove 61 of the optical axis alignment member An error occurring due to an error occurring when the optical axis member is not aligned, a processing error and an assembly error of the alignment groove portion 61 of the optical axis alignment member and the alignment error portion 71 of the OSA, Errors that are caused by not being mounted at a predetermined position are accumulated. In addition, even in the process of die bonding of optical devices, even if the optical devices are not mounted at the predetermined positions due to the equipment error, the optical transmission efficiency is reduced, and external error factors not included in the components of the prior art 3 invention are accumulated The total error can be made larger than the design time. That is, in order to ensure alignment of the optical axes, all of these errors must be managed at the same time, and thus the overall optical transmission efficiency is likely to be low. In addition, since a large number of parts are used to secure the alignment of the optical axes and to provide the structure necessary for stable mounting, it is not only disadvantageous in terms of cost and manufacturing complexity, but also because of the configuration in which the optical device is directly mounted on the PCB substrate ), There is no possibility of directly applying the configuration of the prior art 3 to other applications.

The optical axis alignment method of the present invention includes an optical transmission member 100 for transmitting an optical signal, an optical device 200 for emitting an optical signal to the optical transmission member 100 or receiving an optical signal from the optical transmission member 100, An electrode pad 220 for electrical connection between the optical element 200 and an external circuit and the transfer member 100 are inserted and mounted on the substrate 210, And an optical block (300) having an optical transmission member mounting portion formed in a direction perpendicular to the optical axis of the optical module, the method comprising the steps of: And determining a position of the optical input / output point of the optical device by mounting the optical input / output unit at a position of the optical input / output unit, and positioning the center axis of the optical transmission member mounting unit at the determined position of the optical input / output unit.

The step of positioning the central axis of the optical transmission member mounting portion at the determined position of the light incidence point may include the steps of preparing an optical block having the optical transmission member mounting portion formed therein so that the center axis of the optical transmission member mounting portion is positioned near the light entering / Placing the optical block on the substrate while covering the optical element, and moving the optical block (300) until the position of the optical block (first position) in the optical block satisfying a predetermined condition is searched And repeating the process of measuring the optical transmission efficiency while changing the position of the optical block 300 on the substrate and fixing the optical block 300 to the first position. )

The step of positioning the center axis of the optical transmission member mounting part at the determined position of the light incidence point may include directly molding the optical block on the substrate by the 3D printing method and mounting the optical transmission member on the optical transmission member mounting part And the optical block is formed by including the shape of the optical transmission member mounting portion (second optical axis alignment method)

The 3D printing method includes collecting 3D information of the substrate 300, the optical device 200, and the optical block, processing the collected 3D information to generate 3D information about the optical block including the optical- Dividing the 3D drawing information into unit information for 3D printing; fixing the shaping material according to the unit information to form an initial shaping layer of the optical block at a predetermined position on the substrate; (Ii-A-5) until the shape of the optical block is completed, fixing the shaping material in accordance with the unit information to form a shaping layer on the upper surface of the immediately preceding shaping layer, And repeating steps < RTI ID = 0.0 >

The optical module of the present invention includes an optical transmission member 100 for performing optical axis alignment using the first optical axis alignment method or the second optical axis alignment method described above and for transmitting an optical signal, An optical element 200 that emits an optical signal or receives an optical signal from the optical transmission member 100, a substrate 210 on which the optical element 200 is mounted, an electrical connection 200 between the optical element 200 and an external circuit And an optical block 300 having an electrode pad 220 for mounting the transmission member 100 and an optical transmission member mounting unit to which the transmission member 100 is inserted and formed in a direction perpendicular to the substrate.

The present invention has the advantages of modularization by applying the optical module of the present invention to a variety of other systems as a kind of device or by expanding it, as a first effect that a process systematization and a mass production system can be achieved in order to improve overall optical transmission efficiency Has a second effect.

With respect to the first effect, by using the first optical axis alignment method, an optical block is formed using an injection molding method having advantages of high-speed molding and small manufacturing error, and the center position of the end of the optical- It is possible to maximize the reliability of the optical transmission efficiency through the arrangement of aligning the active light axis with the light incident point of the element 200. When the second optical axis alignment method is used, the position of the optical transmission member mounting portion 310 is optimized in advance, The optical alignment effect can be ensured only by mounting the optical transmission member 100 through the manufacturing process and the total optical axis alignment process time is not required and the total process time can be shortened.

Regarding the second effect, it is not intended to reduce or minimize the operation errors of chip bonding or die bonder equipment having an order of several tens of micrometers, The final mounting position of the optical device 200 is measured and the optical transmission member 100 is aligned with the final position of the optical device 200 to increase the optical transmission efficiency and reduce the misalignment defect rate due to the process error. In other words, it is trying to eliminate the influence of the error of the process equipment in the beginning.

The optical module of the present invention modularizes by adopting the minimum number of components such as the optical device 200, the optical block 300, and the optical transmission member 100, Since the optical alignment of phosphor is solved in the optical module of the present invention alone, when the optical module of the present invention is used in another application, for example, an electronic device such as a mobile phone, The problem is not generated and functions as a so-called optical alignment device. Accordingly, the application does not require a separate structure or alignment key for optical alignment, so that loss of the optical signal from the system-wide viewpoint including the optical module can be reduced, and it is possible to meet the problem of low- In addition, there is no need to photo-align the optical components one by one in the main process of the application, thereby reducing process time and process cost. Further, since the optical element is not mounted on the substrate of the application but is modularized and included in the interior of the present invention, the pattern design on the application side becomes relatively simple, so that the optical module of the present invention can be directly mounted on the PCB substrate There is a high possibility that the present invention can be utilized as various types of mounting such as mounting or coupling to a slot.

FIG. 1 is an explanatory view showing that an optical waveguide is formed by processing the optical transmission member 100 of the conventional art 1 by 45 degrees.
2 is an explanatory view of an optical module composed of a plug and a receptacle of the prior art 2. Fig.
3 is a perspective view showing a configuration (unmodularization) for alignment of optical axes between an optical element and an optical transmission member of Prior Art 3;
4 is a perspective view showing that a photo-voltaic device is mounted on a substrate of the present invention.
5 is a perspective view showing an embodiment of an optical block manufactured for the optical axis alignment method (first optical axis alignment method) of the present invention.
6 is a perspective view showing an embodiment in which an optical block is mounted at an optimum position by using the optical axis alignment method (first optical axis alignment method) of the present invention.
7 is a perspective view showing a state in which an optical transmission member is mounted on an optical block mounted using the optical axis alignment method (first optical axis alignment method) of the present invention.
8 is a schematic diagram showing an embodiment of forming an optical block by 3D printing using an SLS method using the optical axis alignment method (second optical axis alignment method) of the present invention.
9 is a schematic diagram showing an embodiment of forming an optical block by 3D printing using FDM using the optical axis aligning method (second optical axis aligning method) of the present invention.

An optical module to which an optical axis aligning method of the present invention is applied includes an optical transmission member 100 for transmitting an optical signal, a light receiving member for emitting an optical signal to the optical transmission member 100 or receiving an optical signal from the optical transmission member 100 A substrate 210 on which the optical device 200 is mounted; an electrode pad 220 for electrical connection between the optical device 200 and an external circuit; And an optical block 300 having an optical transmission member mounting portion formed in a direction perpendicular to the substrate.

Hereinafter, the optical axis alignment method of the present invention will be described in detail below with reference to the main components.

When the optical module is used in a transmitter, the mounted optical device 200 is a laser diode or a VCSEL, and the optical device 200, which is controlled by an external driving circuit, The optical signal transmitted from the optical transmission member 100 enters the core of the optical transmission member 100 and is transmitted. When the optical module is used in the receiving unit, the mounted optical device 200 becomes a photodiode, and the optical signal transmitted from the optical transmitting member 100 is incident on the light incident surface of the optical device 200 The light is converted into an electric signal by the photoelectric conversion action of the optical element 200, and is transmitted to the external circuit through the electrode pad 220.

As described above, the optical device 200 can be a PD (Photo Diode) as well as a VCSEL and a laser diode (LD) in that the present invention can be applied to both a receiver and a transmitter of an optical signal. The optical transmission member 100 is a known optical fiber, and its diameter and sectional shape are not limited. The substrate 210 has the optical element 200 mounted thereon and supports the optical block 300 to be described later, and a PCB, a flexible PCB (FPCB), or the like can be used.

The electrode pad 220 as in the embodiment shown in FIGS. 4, 6, and 7 serves as an intermediary for transmitting and receiving electric signals between the optical element 200 and the external circuit, Pattern. Since the number of terminals of the optical element 200 is two in the embodiment shown in FIGS. 4, 6, and 7, (220) are also formed. In this embodiment, the electrode pads are formed so as to cover the upper surface of the substrate 210, and the electrode pads are formed so as to extend from the upper surface to the lower surface of the substrate 210 through the side surfaces. . The optical module of the present invention may be configured to be mounted on a separate circuit board through a SMT or reflow process for forming a bump on the bottom surface, It is not. The electrode pad 220 is preferably formed of a conductive metal such as copper or silver, and may be formed in the form of a plated film having a thickness of several tens to several hundreds of micrometers. Electroforming (electroforming, electrolytic casting, electroplating) may be applied as an embodiment of the method for forming a plated film.

5, 6, and 7, the optical block 300 includes a first function to form an optical signal path so as to be able to transmit an optical signal, a first function to form the optical element 200, A second function as a packaging member for protecting them and a third function for mounting and fixing the optical transmission member 100. [ In addition, when the tab portion is formed at the entrance side of the optical transmission member mounting portion 310 formed in the optical block, the optical transmission member 100 can be easily mounted. The shape is preferably, but not limited to, to have a tapered shape as in the case of the embodiment shown in Figs. 6 and 7. The fabrication of the optical block should be different depending on which optical axis alignment method is used, which will be described later.

Hereinafter, the optical axis alignment method of the present invention will be described.

The present invention adopts a so-called butt coupling method in which optical input and output slopes of the optical element 200 and optical signals transmitted by the optical transmission member 100 are perpendicular to each other, An optical block is applied as an intermediate structure for this purpose. When the optical element 200 and the optical transmission member are connected in this manner, the optical transmission member and the optical signal input / output from the optical element 200 can be mutually communicated immediately. However, since the optical input / output slope of the optical device 200 mounted on the upper surface of the horizontal substrate and the traveling direction of the optical signal are relatively perpendicular, a separate structure for fixing the optical transmission member is required. (300). Ideal full optical alignment when adopting a butt coupling configuration is such that the optical exit point of the optical element 200 exactly coincides with the center of the exposed core section of the optical transmission member, And minimizing the distance therebetween.

The optical axis aligning method of the present invention basically comprises the steps of mounting the substrate mounted with the optical device at a predetermined position to determine the position of the optical input / output point of the optical device, and determining the position of the optical input / And positioning the axis. The position of the optical input / output point of the optical device is utilized in the sense that the position should not be changed in the first optical axis alignment method, which will be described later. In the second optical axis alignment method, the information is directly utilized. In the step of positioning the central axis of the optical transmission member mounting portion at the position of the light input / output point, it is impossible to align the optical axis completely, considering the positional error between the respective components constituting the optical module and the manufacturing error inherent in each component In order to achieve a practically possible level of alignment of the optical axes, the present invention proposes two optical axis alignment methods.

One is to search for the point at which the optical transmission efficiency becomes maximum while continuously changing the relative positions of the optical transmission member 100 and the optical device 200 and to determine the position of the optical transmission member 100 (Hereinafter referred to as a first optical axis alignment method) for fixing the relative position of the optical element 200 includes an optical transmission member mounting portion formed in an optical block serving as a platform on which the optical transmission member 100 is mounted, A method of ensuring alignment of the optical axis including the substrate-optical block-optical transmission member by merely aligning the optical axis of the device 200 and mounting the optical transmission member on the optical transmission member mounting portion without a separate additional optical axis alignment process Quot; second optical axis alignment method "). The first optical axis alignment method is a so-called active optical alignment, and the second optical axis alignment method is a so-called passive optical alignment.

Since the first optical axis alignment method utilizes the optical transmission efficiency measured by using the optical measurement equipment, the reliability of the optical axis alignment is high, and the optical module manufactured by a separate process can be inserted into the optical module, The advantage is that it can be kept simple. The second optical axis aligning method proposes a method of forming an optical block such that the position of the central axis of the optical transmission member mounting portion formed in the optical block is within a predetermined error range with respect to the optical input / output point of the optical device 200 And there is no need for a separate optical axis alignment operation, thereby reducing the overall process speed and manufacturing cost.

Hereinafter, the first optical axis alignment method will be described step by step.

First, an optical block having an optical transmission member mounting portion is prepared.

Since the optical signal passes through a certain distance within the optical block, a material having a transmittance of 70% to 100% with respect to the wavelength band of the optical signal used for optical transmission should be used in the production of the optical block. In terms of heat resistance, among these properties, electrical insulation, durability and heat resistance are required. In the process of surface mounting equipment (SMT) and reflow equipment in which the temperature rises to about 300 degrees centigrade, It is preferable that there is little deformation or breakage or a decrease in optical transparency. That is, even in the environment where the optical module of the present invention is implemented in the future, when the optical module is exposed to a reflow process in the process of mounting the process module such as SMT or the mounting of peripheral devices, ) Should have little or no degradation of the physical properties required.

Further, it is preferable that the optical block is manufactured by a method of injection molding or molding. These manufacturing processes are not only suitable for mass production but also can ensure the accuracy of the shape of the optical transmission member mounting portion provided in the optical block. In recent years, due to the development of manufacturing techniques such as injection molding, .

It is preferable that an optical element accommodating cavity capable of accommodating the optical element is formed in a portion of the optical block which is in contact with the lower substrate. This is because in the first optical axis aligning method, The optical block does not interfere with the optical block. Therefore, the optical block does not encapsulate the optical element, but has a shape that covers only the optical element accommodating cavity with a predetermined distance, and accordingly, the size of the optical element accommodating cavity is set in consideration of a possible moving path of the optical block Should be determined.

Secondly, the optical block is placed on the substrate while covering the optical element so that the central axis of the optical transmission member mounting portion is located near the optical input / output point of the optical element. The optical element is located inside the optical element housing cavity. The term 'near' here means that when observing with the naked eye or putting it at a predetermined position using a machine, the error inevitably occurs due to the limitation of visual and mechanical operations.

Third, while the position of the optical block 300 is changed and moved on the substrate until a position (first position) of the optical block satisfying a predetermined condition is searched for at the substrate (first position), the optical transmission efficiency Is repeated. Measurement of the optical transmission efficiency may be performed in a state in which the optical transmission member is mounted on the optical transmission member mounting portion, or measurement may be performed by providing a separate measurement device without mounting the optical transmission member. In the latter case, mounting the optical transmission member on the optical transmission member mounting portion will be performed after fixing the optical block to the substrate. The first optical axis alignment method regards the optical axis alignment as being performed when the optical transmission efficiency is measured and the value thereof satisfies a predetermined condition. Therefore, an example of the predetermined condition is that the optical transmission efficiency is 95% or more . If the reference optical transmission efficiency value is too high, it will take a long time to search for the first position beyond the reference value, and if it is too low, the quality of the optical module will be lowered. Specifically, the optical transmission efficiency is measured and calculated using a measuring instrument such as an optical spectrum analyzer.

Fourthly, the optical block 300 is fixed to the first position. The base material may be fixed on the substrate 210 by using a separate adhesive or by locally fusing the surface of the optical block by irradiating a laser to the surface (Fused) to the substrate 210 after the deposition. In the case of the former, an ultraviolet (UV) curable adhesive may be used, but the present invention is not limited thereto.

Hereinafter, the second optical axis alignment method will be described.

In the second optical axis alignment method, after a substrate on which optical elements are mounted is fixed at a predetermined position, the optical block is directly formed on the substrate including the shape of the optical transmission member mounting portion by the 3D printing method, And attaching an optical transmission member to the optical fiber.

The 3D printing step firstly acquires 3D information of the substrate 210, the optical element 200, and the optical block. The 3D information of the substrate and the optical device should include the position and size information of the substrate and the optical device, and they are needed in determining the final shape of the optical block in the future. Particularly, the position coordinate value of the light incidence point of the optical element is important, and the second optical axis alignment method is to align the light incidence point and the optical transmission member mounting portion. As a method for securing the coordinate value, a method of photographing an image of a substrate and an optical element mounting portion of a substrate with a camera, calculating through processing, or a method using a general-purpose 3D object scanner can be applied. It is not. The calculation method of the coordinate value can also be applied to various methods such as a method of calculating the displacement based on a specific point at which the coordinate value is known, or a method using the absolute coordinate value. The 3D information of the optical block will be the size of the optical block, the desired depth and desired diameter of the optical transmission member mounting part, etc. Since the optical block is not yet formed before molding, will be.

Second, the 3D information is processed to generate 3D drawing information for the optical block including the optical transmission member mounting portion. In this step, the 3D information collected as described above is processed to determine the shape of the optical block having a perfect shape. Particularly, the optical axis member mounting portion is shaped so that the central axis thereof is aligned on the light incidence point of the optical device. The generation of such 3D drawing information is processed using software.

Third, the 3D drawing information is divided into unit information for 3D printing. Such unit information is processed by software, and the format of the unit information depends on which 3D printing process is used. For example, in a 3D printing process of forming a three-dimensional molding shape by sequentially laminating a shaping layer on an immediately preceding shaping layer, the unit information may be shape information of an individual shaping layer. In another example, in the 3D printing process of forming a pattern by ejecting the molding material in a zigzag manner using the inkjet method, the unit information may include the movement path of the inkjet nozzle head.

Fourth, the shaping material is fixed according to the unit information, and the first shaping layer of the optical block is formed at a predetermined position on the substrate. Fifth, the shaping material is fixed according to the unit information, and a shaping layer is further formed on the upper surface of the immediately preceding shaping layer. Sixth, the fifth step is repeated until the final shape of the optical block is completed. The interval between the molding operations of each molding layer is determined by considering the speed of hardening / sintering of the molding material.

The supplied molding material can be prepared from a liquid photo-curable resin 540 or a powdery resin. When the light curing resin 540 mainly has a liquid phase and receives light, the inter-polymer links in the resin rapidly cure (cross link), so that what kind of photo-cured resin 540 is adopted is determined by the curing rate The wavelength of the shaping beam 530, and the like. Further, in the case of supplying the molding material with the powdery resin, each molding layer is produced by the phenomenon that the powdery resin of the corresponding part is melted / sintered by the irradiation of the molding light source and then cured while being air-cooled again. The choice of powdery resin should be determined taking into account the sintering / melting rate and the wavelength of the shaping beam 530 used. Whether liquid phase curing resin 540 or powdered resin is applied to the molding material, the light transmittance of the optical block after molding must satisfy predetermined criteria. Measurement of light transmittance and the like can utilize indices such as haze or transparency. A material having a transmittance of 70% to 100% with respect to a wavelength band of an optical signal used for optical transmission should be used. As a material having such a high transmittance, any one or more of silicon, epoxy, ABS, acrylic, polyolefin, and copolymers thereof can be selected and applied , But is not limited thereto. In short, the molding material should be selected to have both photo-curability / sinterability, light transmittance, hardness (hardness) and the like.

The shaping material can be fixed by irradiating the shaping light beam 530 as single light, synthesized light, or combined light selectively formed by ultraviolet (UV), near infrared (NIR), or laser light having a predetermined wavelength In the concrete determination, the types and characteristics of the resins to be applied should be taken into consideration. Composite light is to make a light beam with different wavelengths or powers into one light beam (light stalk), and combining light means irradiating the same point with multiple light beams having different wavelengths or powers.

Fixing of the molding material can be performed by a 3D printing process of FDM, DLP, SLS, or SLA.

9, the FDM (Fused Deposition Modeling) system is a system in which a molding material is melted and discharged through a head nozzle, the head nozzle is moved through a predetermined path to form an overall shape, It is characterized by low process cost. The DLP (Digital Light Processing) system is a system in which the curing resin is hardened by using the light source of the projector, and the color filter is released from the projector during the printing process so that the fluorescent light is emitted, High-speed molding is possible by hardening.

The SLA (Stereolithography Apparatus) method as shown in FIG. 8 is a method of applying a liquid photopolymer resin 540 using a scanning head. Fig. 8 (a) shows an intermediate step of 3D printing, and Fig. 8 (b) shows an ending step. The photocurable resin tank 540 is contained in the photocured resin tank 510. After the first shaping layer is formed on the shaping stage 520, the shaping stage 520 is moved downward by one shaping layer thickness, The photocurable resin 540 is present in an uncured state between the upper surface of the molding stage 520 and the immediately preceding molding layer surface. And selectively irradiating a shaping light beam 530 to this portion to form one shaping layer.

In addition, the SLS (Selective Laser Sintering) method has a merit that a high-quality molding can be formed by melting / sintering powdery metal or resin with strong energy of laser. After the shaping material is planarized, the surface is irradiated with a laser to partially melt it, and then the shaping material is fed again to perform planarization. In DLP (Digital Light Processing), the UV light is used in the light source of the projector to harden the UV curable resin. During the printing process, the color filter is removed from the projector to emit UV light, and the process of curing the screen by slicing the single slice on the screen is repeated.

In addition, a method using image pickup as another embodiment for the optical alignment of the optical module of the present invention will be described in detail for each step.

First, the optical device is mounted on one surface of the substrate 210. A method of applying a paste or an adhesive for attaching to the surface of the optical element 200 and attaching the paste to a mounting surface is performed by using a chip bonder or a die bonder It is possible to automate it. The die bonder typically uses air suction to lift one side of the chip and then mounts it to the mounting location of the chip. At this time, the paste having conductivity can be applied.

Second, the optical element 200 is mounted. As a method of electrically connecting the mounted optical element 200 to the electrode pad 220, any one of wire bonding, flip chip bonding, surface mounting technology (SMT), and reflow method can be selected.

Wire bonding is achieved by electrically connecting an optical element to a substrate, and a thermocompression bonding process and an ultrasonic bonding method can be considered. In the thermo-compression process, heat and pressure are applied to form a joint, and an end portion of a wire having a diameter of 10-20 μm is melted using an electric discharge or a torch, and pressure is applied to form a ball bond. A capillary tip is used as a bonding condition, and a pressure is applied to a wire at a second bonding position to form a bonding portion, which is called a wedge bond. The bonding speed is approximately 6 bpm (bond per minute). In the ultrasonic bonding process, the wire is bonded to the pad at room temperature by applying the vertical pressure and the ultrasonic vibration of about 60 KHz in the horizontal direction. The oxide film breaks due to pressure and vibration, and metal contact occurs, and it works at room temperature, forming a cold weld. The joints at both ends of the pad are in the form of a ball-wedge or a wedge-wedge bond, and in the case of a wedge-wedge bond, a capillary tip and other types of tools Tool) can be used. As the wire material, Au or Cu is used and the bonding speed is about 240 bpm (bond per minute). Flip chip bonding is a method of attaching an optical element to the back surface of a substrate by bonding an optical element and a substrate using gold or a solder bump. Further, when a conductive paste is applied to the back surface of the device and hot air is applied using a reflow equipment, the paste is melted to form a solder ball. This is called SMT (Surface Mount Technology) Which is advantageous for low-volume and miniaturization. In the embodiment of FIG. 4, an optical device is mounted on the substrate 210 in a wire bonding manner, and each of the optical device terminals is individually connected to each of the electrode pads 220 so as to process the related electric signal.

Third, the position of the mounted optical element 200 on the two-dimensional plane of the light incidence point is calculated. This value is a key parameter in the design for the marginal light alignment. This is achieved by forming the optical transmission member mounting portion 310 accurately so that the central axis of the optical transmission member mounting portion 310 is located at the calculated position of the input / Since alignment can be assured. When the optical transmission member 100 having a diameter of only a few hundred micrometers is used, the mounting position of the optical element 200 is measured with the naked eye, and the optical transmission member mounting portion 310 is machined at the position, The present invention proposes to use a vision system including a camera, and this configuration can be referred to as a so-called vision feedback process. That is, according to the present invention, the mounting position of the optical device 200 is determined in advance, and the optical device 200 is not intended to be mounted with a minimum error, It is proposed to form the optical transmission member mounting portion 310 at that position. As a result, it is possible to obtain an effect of eliminating a work error inherently inherent in a die bonder and the like, thereby assuring optical alignment.

Such a vision system can have an image processing apparatus as an essential component in addition to a camera. One embodiment of the method for calculating the position of the optical device 200 on the two-dimensional plane of the light incidence point using the vision system will be described below in each step. One is to determine the position to be measured of the optical element according to the shape of the optical element. For example, when the cross-sectional shape of the optical element is a positive circle, a specific point on the circumference where the distance is maximum with respect to one reference point is found, and the positions of the reference point and the specific point, Or if the cross-sectional shape of the outline of the optical element is a rectangle or a square, it can be decided to measure the position of two diagonal points among the four vertexes. Both photographs an image of an optical device mounted using a camera. The set determines the position on the two-dimensional plane for each position-to-be-measured part determined in advance from the image. That is, in the above example, the positions of two vertexes of two points or squares having a diameter of the circumference are measured. The position may be a value relative to the absolute coordinate system of the measurement system or a relative coordinate value relative to a specific reference point whose absolute coordinate value is known. The two-dimensional plane position alone is sufficient because the optical transmission member mounting portion 310 is formed perpendicular to the substrate surface, so that the coordinate value in the height direction is meaningless. The net calculates the position of the light incidence point on the two-dimensional plane of the optical element 200 from the two-dimensional plane position values of each position measurement object determined in the previous step. Although the shapes of the optical elements may be different from each other, it is generally assumed that the optical input / output points are located at the center of the optical element. In this example, the midpoints of two vertexes forming diagonal lines It is calculated by calculating the position coordinate value of each point by the average of the coordinates system of the coordinate system. The above embodiment does not exclude other algorithms that perform the same purpose as one example of finding a location value on a two-dimensional plane of a light incidence point.

Fourth, a base material of the optical block 300 is formed to embed the optical element 200 on the substrate 210. In order to reliably mount the optical transmission member 100, it is important that the base material is strongly coupled to the substrate 210. [ As an embodiment of the method of forming the base material on the substrate 210, injection molding or molding directly on the substrate 210 may be considered. In this case, strong bonding with the substrate can be maintained, Thereby encapsulating the optical element completely. As another embodiment, the base material may be pre-formed by an injection molding or molding process so as to have a shape of a cavity portion for accommodating an optical element at a lower portion thereof, It is a method of welding. In this case, the base material does not encapsulate the optical element, but has a shape covering only a predetermined distance by the cavity portion. For fixing the base material on the substrate 210, a separate adhesive may be used, or a UV laser It is possible to apply a method of irradiating the surface of the base material and fusing it locally to the substrate 210.

Fifth, the optical transmission member mounting portion 310 on the base material is formed with respect to the calculated position of the light incidence point on the two-dimensional plane. In the embodiment shown in FIGS. 5 to 7, since the optical transmission member mounting portion 310 has a cylindrical shape or a cylindrical shape, it is processed into a cylindrical shape with the center position of the calculated position of the input / output point on the two- Value is determined so as to enable tight fitting with respect to the diameter value of the optical transmission member mounting portion 310. [ Such processing can be performed by a laser processing, a CNC processing, or a drilling processing. The common feature of these processes is that they are processed on the basis of the precise position value of the work site, and thus are suitable for machining the optical transmission member mounting portion 310 of the present invention. In the case of a mechanical drilling process, a second step of boring, which creates a hole having a cylinder shape at a precise position and seats the hole, and a diameter of an exact hole through the additional hole in the hole created in the first step Processing can be performed. In this case, precise positioning in step 1 should be done by using a computer and a machine to transfer and fix the drill tip. In the case of using the CNC process, since the shape information of the hole is inputted to the computer in advance and the cutting is performed based on the information, there is an advantage that the machining time can be shortened. The laser machining process is based on non-contact work, suitable for automated line configuration, precise control, and high-speed scan speed enables short process times. Examples of the laser used include a UV laser, a carbon dioxide gas laser, and the like, and can be selected from a percussion method, a trepanning method, a helical method or the like according to a puncturing method. The specific operation is performed by controlling the energy of one shot, the number of shots, the total energy sum, etc. according to the thickness of the substrate 210. In this case as well, the control must be precisely performed by a computer and a machine so that the shot can start machining centering on the position of the light incidence point two-dimensional position of the optical element 200 calculated previously. In the formation of the tab portion 312, in the case of a mechanical drilling process, a taper slope is created by further cutting. In the case of using the CNC and the laser machining process, the shape information of the tapered hole is inputted to the computer in advance.

Sixth, the optical transmission member 100 is mounted on the optical transmission member mounting portion 310 thus processed. In order to further improve the reliability of mounting, it may be considered to add a step of fixing the optical transmission member and the optical transmission member mounting hole by using an adhesive such as epoxy in the mounting process.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it should be understood that various changes and modifications will be apparent to those skilled in the art. It is to be understood that the present invention is not limited to the above-described embodiments. Accordingly, the scope of protection of the present invention should be construed according to the following claims, and all technical ideas which fall within the scope of equivalence by alteration, substitution, substitution, Range. In addition, it should be clarified that some configurations of the drawings are intended to explain the configuration more clearly and are provided in an exaggerated or reduced size than the actual configuration.

100: optical transmission member
200: Optical element
210: substrate
220: Electrode pad
230: Bonding wire
300: Optical block
310: optical transmission member mounting portion
312:
313: Optical element accommodating cavity part

510: Photocurable resin tank
520: molding stage
530: plastic beam
540: Photocurable resin
n, n + 1: nth and n + 1 th shaping layers
N: final shaping layer (Nth)


600: Head nozzle
610: Discharge site

Claims (15)

An optical element 200 for emitting an optical signal to the optical transmission member 100 or receiving an optical signal from the optical transmission member 100; An electrode pad 220 for electrical connection between the optical element 200 and an external circuit and an optical transmission line 220 formed by insertion of the transmission member 100 and formed in a direction perpendicular to the substrate, A method of aligning an optical axis between an optical element and an optical transmission element with respect to an optical module including an optical block (300) having an element mounting portion,
(i) mounting the substrate on which the optical device is mounted to a predetermined position to determine a position of the optical input / output point of the optical device;
(ii) a step (s20) of positioning the central axis of the optical transmitting member mounting part at the position of the light incidence point determined in the step (i);
And the optical axis of the optical module. The method according to claim 1,
The step (ii)
(ii-a) preparing (s20a) an optical block in which the optical transmission member mount is formed;
(ii-b) placing the optical block on the substrate while covering the optical block so that the central axis of the optical transmitting member mounting portion is located near the light incidence point (s20b);
(ii-c) changing and moving the position of the optical block 300 on the substrate until the position of the optical block (first position) of the optical block satisfying a predetermined condition is searched for , Repeating the process of measuring the optical transmission efficiency (s20c);
(ii-d) fixing the optical block 300 to the first position (s20d);
And the optical axis of the optical module. The method according to claim 1,
Wherein the optical block in the step (i) has an optical element accommodating cavity portion at a lower portion thereof for accommodating the optical element. The method according to claim 1,
Wherein the optical block (300) in the step (i) is manufactured by a method of injection molding or molding. The method of claim 2,
And mounting the optical transmission member on the optical transmission member mounting portion between the step (ii-a) and the step (ii-b). The method of claim 2,
And mounting the optical transmission member to the optical transmission member mounting unit after the step (ii-d). The method of claim 2,
Wherein the optical block in the step (ii-d) is fixed on the substrate by a fusion bonding method. The method of claim 7,
Wherein the fusing of the optical block on the substrate is performed by irradiating a laser beam onto a lower surface of the optical block. The method of claim 2,
Wherein the optical block in the step (ii-d) is fixed on the substrate by a bonding method using an adhesive. The method according to claim 1,
The step (ii)
(ii-A) directly molding (s20A) the optical block on the substrate by a method of 3D printing;
(ii-B) mounting (S20B) the optical transmission member to the optical transmission member mounting portion;
, ≪ / RTI >
Wherein the optical block in the step (ii-A) includes a shape of the optical transmission member mounting part. The method of claim 10,
The step (ii-A)
(ii-A-1) collecting 3D information (s20A-1) of the substrate 300, the optical device 200, and the optical block;
(ii-A-2) step (s20A-2) of processing the 3D information collected in the step (ii-A-1) to generate 3D drawing information for the optical block including the optical transmission member mounting part;
(ii-A-3) dividing the 3D drawing information from the step (ii-A-2) into unit information for 3D printing (s20A-3);
(ii-A-4) fixing the molding material according to the unit information in the step (ii-A-3) and molding the first molding layer of the optical block at a predetermined position on the substrate (s20A-4);
(ii-A-5) a step (s20A-5) of fixing the shaping material according to the unit information in the step (ii-A-3) to further form a shaping layer on the upper surface of the immediately preceding shaping layer;
(ii-A-6) repeating the step (ii-A-5) (s20A-6) until the shape of the optical block is completed;
And the optical axis of the optical module.
The method of claim 11,
The shaping material supplied in the step (ii-A-4) and the step (ii-A-5) is a photocurable resin 540 having transparency to the optical wavelength band of the optical signal, Wherein the optical axis of the optical module is aligned with the optical axis of the optical module. The method of claim 11,
Wherein the molding material supplied in the step (ii-A-4) and the step (ii-A-5) is a resin having permeability to a light wavelength band of the optical signal and is prepared in the form of a powder A method of aligning an optical axis of a module. The method of claim 11,
The fixing of the molding material in the step (ii-A-4) and the step (ii-A-5) can be performed by selecting among ultraviolet (UV), near infrared (NIR), or laser light having a predetermined wavelength (530) as a single light, a combined light, or a combined light to be formed. The method of claim 11,
The fixation of the molding material in the step (ii-A-4) and the step (ii-A-5) is characterized by a 3D printing process of SLS, DLP, FDM or SLA Of the optical module.

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