An alignment system and method for optical wire bonding

Abstract

This invention discloses an alignment system and method for optical wire bonding, relating to the field of laser technology. The alignment system includes an exposure device and a control device. A first and second dichroic mirror of the exposure device are set at a preset angle to receive a first beam from a first laser unit and a second beam from a second laser unit, respectively. The emitted light from the first and second dichroic mirrors is projected onto a displacement stage through an objective lens to form a bonding beam. The first and second beams are superimposed to form a bonding beam with a smaller diameter. The control device includes a tip sensor, a displacement stage drive, and a control system. By forming a control closed loop with the tip sensor, control system, and displacement stage drive, timely adjustments are made to address the coordinate error between the bonding position of the optical wire bonding device and the bonding beam, increasing the accuracy of the alignment system and thus improving the yield of optical wire bonding.

Description

Technical Field

[0001] This invention relates to the field of laser technology, and in particular to an alignment system and method for optical wire bonding. Background Technology

[0002] With the rapid development of electronic information technology, especially the realization of large-scale integration technology, traditional copper conductors in printed circuits can no longer meet the stringent requirements for line length, signal attenuation, distortion, and crosstalk in high-end electronic systems. The advantages of incorporating optoelectronic circuits into printed circuit boards are becoming increasingly apparent, leading to the development of a new type of optoelectronic printed circuit board (OEPCB). The realization of OEPCB solves many problems associated with traditional PCB circuits, such as skin effect, electromagnetic interference, and dielectric loss. Furthermore, OEPCB significantly improves the efficiency of communication and signal transmission, truly achieving high-speed interconnection and ensuring signal integrity.

[0003] Due to the applications of optoelectronic printed circuit boards (PCBs) and optical-electronic integrated circuits (OEICs), photonic wire bonding (PWB) has been proposed. This method uses optical waveguides instead of traditional metal wires to interconnect different optical chips and between chips and optical fibers. By connecting the optical fiber output port of the PCB to the optical fiber input port of the OEIC using optical wires, the chip and fiber are connected. This method avoids the need for lenses and other components required for beam shaping in traditional methods, and its fabrication is simple and quick, facilitating large-scale production. However, to achieve the interconnection between the chip and the fiber, alignment is required during the bonding of the optical waveguide, PCB, and OEIC; therefore, higher precision is required for the alignment system. Summary of the Invention

[0004] The purpose of this invention is to provide an alignment system for optical wire bonding, which improves the alignment accuracy of optical wire bonding.

[0005] To address the aforementioned technical problems, the present invention provides a first solution: an alignment system for optical wire bonding, the alignment system comprising:

[0006] An exposure apparatus, comprising a first laser unit for providing a first light beam, a second laser unit for providing a second light beam, a first dichroic mirror, a second dichroic mirror, an objective lens, and a displacement stage. The first and second dichroic mirrors are positioned at a preset angle to receive the first light beam from the first laser unit and the second light beam from the second laser unit, respectively. The light emitted from the first and second dichroic mirrors is incident on the displacement stage through the objective lens to form a bonding beam. The displacement stage is used to place an optical wire bonding device.

[0007] Control device, the control device comprising:

[0008] A needle tip sensor device is used to measure the coordinate error between the bonding position of the optical wire bonding device and the bonding beam;

[0009] A displacement stage driving device, the displacement stage driving device being used to control the movement and rotation of the displacement stage; and,

[0010] A control system is used to compensate for the coordinate error by controlling the displacement stage drive device to adjust the coordinate position of the displacement stage.

[0011] Furthermore, the control system also includes a dichroic mirror driving device, which is used to adjust the position and orientation of the first dichroic mirror and the second dichroic mirror.

[0012] Furthermore, the needle tip sensor device also includes a cantilever, one end of which is fixed and the other end of which is provided with a needle tip sensing head.

[0013] Furthermore, the tip sensor device includes one or more tip sensing heads, which are fixed to one or both sides of the exposure device by the cantilever.

[0014] To solve the above-mentioned technical problems, the present invention provides a second solution: an alignment method for optical wire bonding, applied to the aforementioned alignment system for optical wire bonding, the alignment method for optical wire bonding comprising:

[0015] The optical wire bonding device is placed on the displacement stage.

[0016] The first and second laser units are activated to obtain a bonding beam;

[0017] The position coordinates of the bonding beam and the bonding position of the optical wire bonding device are obtained by scanning using a needle tip sensor device, and the coordinate error between the bonding position of the optical wire bonding device and the bonding beam is calculated.

[0018] The coordinate error is compensated by adjusting the coordinate position of the displacement stage by controlling the displacement stage drive device.

[0019] Furthermore, the control system controls the dichroic mirror drive device to adjust the position and orientation of the first and second dichroic mirrors.

[0020] The alignment system for optical wire bonding in this embodiment of the invention includes an exposure device and a control device. The exposure device includes a first laser unit for providing a first beam and a second laser unit for providing a second beam. A first dichroic mirror and a second dichroic mirror are set at a preset angle to receive the first beam from the first laser unit and the second beam from the second laser unit, respectively. The light emitted from the first and second dichroic mirrors is respectively projected onto a displacement stage through an objective lens to form a bonding beam. The superposition of the first and second beams can form a bonding beam with a smaller diameter, which is more suitable for the delicate application of optical wire bonding. The control device includes a tip sensor device, a displacement stage drive device, and a control system. The alignment system forms a control closed loop through the tip sensor device, the control system, and the displacement stage drive device, and adjusts in real time for the coordinate error between the bonding position of the optical wire bonding device and the bonding beam, increasing the accuracy of the alignment system and thus improving the yield of optical wire bonding. Attached Figure Description

[0021] Figure 1 This is a schematic diagram illustrating the application scenario of optical wire bonding in this invention;

[0022] Figure 2 This is a schematic diagram of the overall device of the present invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Figure 1 This is a schematic diagram illustrating the application scenario of optical wire bonding in this invention. For example... Figure 1As shown, in related technologies, the optical wire bonding device includes an optoelectronic printed circuit board 100, an optoelectronic integrated circuit 200, and an optical lead 300. The optoelectronic printed circuit board 100 and the optoelectronic integrated circuit 200 are connected by ball pads 220. The optoelectronic printed circuit board 100 includes a multilayer board 110 and an optical waveguide layer. The optical waveguide layer includes a support layer 121 and a waveguide layer 122. The waveguide layer 122 can be a single-mode optical fiber, specifically including a core 1221 and a cladding 1222. The optical lead 300 includes a core 310 and a waveguide 320. The first end 301 of the optical lead 300 is bonded to the light outlet of the core 1221 in the optoelectronic printed circuit board 100, and the second end 302 of the optical lead 300 is bonded to the light inlet of the photonic device 210 of the optical integrated circuit 200, thereby realizing the connection between the chip and the optical fiber. During bonding, adhesive needs to be applied between the bonding components and then cured by laser irradiation. However, due to the contact between the bonding parts, adhesive may overflow. Therefore, since the adhesive area is larger than the bonding area, the laser spot size needs to be precisely controlled to cure only the adhesive in the bonding part and remove the overflowing adhesive.

[0025] The invention employs a dual-beam laser superposition technology, which uses two visible beams, one as the manufacturing beam and the other as the auxiliary beam. By superimposing the two beams, the diffraction limit of light is overcome, enabling the spot diameter to be smaller than that of a 365-nanometer wavelength ultraviolet light source when using a longer wavelength visible light source, thus achieving higher precision.

[0026] Figure 2 This is a schematic diagram of the overall device of the present invention. Figure 2 As shown, the alignment system for optical wire bonding in this embodiment of the invention includes an exposure device 10. Specifically, the exposure device 10 includes a first laser unit 11 for providing a first light beam, a second laser unit 13 for providing a second light beam, a first dichroic mirror 12, a second dichroic mirror 14, an objective lens 15, and a displacement stage 16. The first dichroic mirror 12 and the second dichroic mirror 14 are set at a preset angle to receive the first light beam from the first laser unit 11 and the second light beam from the second laser unit 13, respectively. The light emitted from the first dichroic mirror 12 and the second dichroic mirror 14 is incident on the displacement stage 16 through the objective lens 15 to form a bonding beam. The displacement stage 16 is used to place the optical wire bonding device. The superposition of the first light beam and the second light beam can form a bonding beam with a smaller diameter, which is more suitable for the delicate scenarios of optical wire bonding.

[0027] The alignment system for optical wire bonding also includes a control device 20, specifically, the control device 20 includes:

[0028] The tip sensor device 22 is used to measure the coordinate error between the bonding position of the optical wire bonding device and the bonding beam;

[0029] The displacement stage drive device 23 is used to control the movement and rotation of the displacement stage 16; and,

[0030] The control system 20 is used to compensate for the coordinate error by adjusting the coordinate position of the displacement stage through the control of the displacement stage drive device.

[0031] The alignment system forms a control closed loop through the tip sensor device 22, the control system 20 and the displacement stage drive device 23. It makes timely adjustments to the coordinate error between the bonding position of the optical wire bonding device and the bonding beam, thereby increasing the accuracy of the alignment system and improving the yield of optical wire bonding.

[0032] Furthermore, the control system also includes a dichroic mirror drive device 21, which is used to adjust the position and orientation of the first dichroic mirror 12 and the second dichroic mirror 14 to adjust the focus of the first beam and the second beam to form a suitable bonding beam.

[0033] Furthermore, the needle tip sensor device 22 also includes a cantilever, with one end of the cantilever fixed and the other end of the cantilever equipped with a needle tip sensor head.

[0034] Furthermore, the tip sensor device 22 includes one or more tip sensing heads, which are fixed to one or both sides of the exposure device by cantilever.

[0035] Furthermore, the first laser unit may include a first laser, a beam expander lens group, and a modulation lens group arranged sequentially.

[0036] Furthermore, the second laser unit may include a second laser, a beam expander lens group, and a modulation lens group arranged sequentially.

[0037] This application also provides an alignment method for optical wire bonding, applied to the aforementioned alignment system for optical wire bonding. The alignment method for optical wire bonding includes:

[0038] Step S1: Place the optical wire bonding device on the displacement stage.

[0039] Step S2: Turn on the first laser unit and the second laser unit to obtain a bonding beam;

[0040] Step S3: Use the tip sensor device to scan and obtain the position coordinates of the bonding beam and the bonding position of the optical wire bonding device, and calculate the coordinate error between the bonding position of the optical wire bonding device and the bonding beam.

[0041] Step S4: Compensate for the coordinate error by adjusting the coordinate position of the displacement stage by controlling the displacement stage drive device.

[0042] The alignment system uses a closed-loop control system consisting of a tip sensor, a control system, and a displacement stage drive to adjust the coordinate error between the bonding position of the optical wire bonding device and the bonding beam in real time, thereby increasing the accuracy of the alignment system and improving the yield of optical wire bonding.

[0043] Furthermore, the method also includes step S5: adjusting the position and orientation of the first and second dichroic mirrors by controlling the dichroic mirror driving device through the control system, so as to adjust the focus of the first beam and the second beam to form a suitable bonding beam.

[0044] The embodiments described above are merely illustrative of implementation methods of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An alignment system for optical wire bonding, characterized by, The alignment system includes: An exposure apparatus, comprising a first laser unit for providing a first light beam, a second laser unit for providing a second light beam, a first dichroic mirror, a second dichroic mirror, an objective lens, and a displacement stage. The first and second dichroic mirrors are positioned at a preset angle to receive the first light beam from the first laser unit and the second light beam from the second laser unit, respectively. The light emitted from the first and second dichroic mirrors is incident on the displacement stage through the objective lens to form a bonding beam. The displacement stage is used to place an optical wire bonding device. Control device, the control device comprising: A needle tip sensor device is used to measure the coordinate error between the bonding position of the optical wire bonding device and the bonding beam; A displacement stage driving device, the displacement stage driving device being used to control the movement and rotation of the displacement stage; and, A control system is used to compensate for the coordinate error by controlling the displacement stage driving device to adjust the coordinate position of the displacement stage. In this process, both the first beam and the second beam are visible light, with one serving as the manufacturing light and the other as the auxiliary light. By superimposing the two beams, the diffraction limit of light is broken, so that when using a longer wavelength visible light source, the spot diameter can still be smaller than that when using a 365-nanometer wavelength ultraviolet light source.

2. The alignment system for optical wire bonding according to claim 1, characterized in that, The control system also includes a dichroic mirror driving device, which is used to adjust the position and orientation of the first dichroic mirror and the second dichroic mirror.

3. The alignment system for optical wire bonding according to claim 1 or 2, characterized in that, The needle tip sensor device also includes a cantilever, one end of which is fixed and the other end of which is provided with a needle tip sensor head.

4. The alignment system for optical wire bonding according to claim 3, characterized in that, The tip sensor device includes one or more tip sensing heads, which are fixed to one or both sides of the exposure device by the cantilever.

5. An alignment method for optical wire bonding, characterized in that, The alignment system for optical wire bonding according to any one of claims 1 to 4, and the alignment method for optical wire bonding, include: The optical wire bonding device is placed on the displacement stage. The first and second laser units are activated to obtain a bonding beam; The position coordinates of the bonding beam and the bonding position of the optical wire bonding device are obtained by scanning using a needle tip sensor device, and the coordinate error between the bonding position of the optical wire bonding device and the bonding beam is calculated. The coordinate error is compensated by adjusting the coordinate position of the displacement stage by controlling the displacement stage drive device.

6. The alignment method for optical wire bonding according to claim 5, characterized in that, The control system controls the dichroic mirror drive device to adjust the position and orientation of the first and second dichroic mirrors.

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