Method for coupling silicon-based optical waveguide and optical fiber array

Abstract

The invention discloses a method for coupling a silicon-based optical waveguide and an optical fiber array, which belongs to the technical field of optical fiber array coupling, and comprises the following steps: 1) carrying out high-precision grinding on the end surface of the optical fiber array, and cleaning and detecting the coupling surface; 2) debugging a coupling platform; 3) debugging the packaging platform; 4) debugging insertion loss test equipment; and 5) completing coupling-packaging-testing, and taking out a finished product from the platform. According to the method, the end face precision of the optical fiber array is improved to 10 [mu] m through a high-precision grinding process, meanwhile, a platform which can be monitored and adjusted in real time and is used for butt coupling and packaging of the silicon optical waveguide chip and the optical fiber array is provided, and equipment parameters of all links are adjusted according to coupling loss displayed by a power meter. The loss of each process in the packaging stage is adjusted to the minimum, and the controllability and high efficiency of the silicon-based optical waveguide coupling packaging process are ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of optical fiber array coupling, and in particular relates to a method for coupling a silicon-based optical waveguide with an optical fiber array. Background Art

[0002] In the field of integrated photonics, the transmission of light energy between optical waveguides or between chips and optical fibers has always been a key issue. For high-speed silicon photonic modules, the optical signal emitted by the laser needs to enter other optical path devices, and finally the optical path signal also needs to enter the detector for photoelectric conversion. This process of sending and receiving involves the transmission of optical signals between different media. The optical path coupling efficiency can be improved by improving the end face polishing accuracy of the optical fiber array and real-time monitoring of the loss of the coupling process to achieve the high density and high speed requirements of the optical module.

[0003] At present, array coupling is an important form of optical interaction between multi-channel optical devices and the outside world. Since the simultaneous alignment and coupling of multiple ports is required, the coupling errors of the ports will accumulate, which is more difficult than single-port coupling. The coupling between standard single-mode fiber arrays and silicon-based waveguide arrays will be an important means to solve the problem of large-scale, high-density integrated silicon photonic chips and external optical interconnection in the future. Therefore, it is necessary to provide a method for coupling silicon-based optical waveguides with optical fiber arrays to ensure the controllability and efficiency of the silicon-based optical waveguide coupling packaging process. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a method for coupling a silicon-based optical waveguide with an optical fiber array. The end face accuracy of the optical fiber array is improved to 10 μm through a high-precision grinding process. At the same time, a platform for docking, coupling and packaging of a silicon optical waveguide chip and an optical fiber array that can be monitored and adjusted in real time is provided. The equipment parameters of each link are adjusted according to the coupling loss displayed by the power meter, and the loss of each process in the packaging stage is adjusted to the minimum, thereby ensuring the controllability and efficiency of the silicon-based optical waveguide coupling packaging process. The specific steps are as follows: 1) Use auxiliary polishing MT ferrule to perform high-precision polishing on the end face of the optical fiber array, clean and inspect the coupling surface, and ensure that the distance tolerance of the optical fiber end face is less than 10μm; 2) Debug the coupling platform and adjust the component positions and parameters of the platform according to the fiber array structure to be coupled; 3) Debug the packaging platform and adjust the platform tooling through the coupling surface structure that needs to be packaged to ensure the stability of packaging curing; 4) Debug the insertion loss test equipment, complete the optical path connection of the insertion loss equipment according to the signal loop of the optical waveguide, observe the insertion loss of the coupling in real time, adjust the coupling platform according to the loss change, perform glue dispensing and packaging curing after meeting the standard, and monitor the insertion loss globally; 5) Complete coupling-packaging-testing and remove the finished product from the platform.

[0005] Preferably, the coupling platform, the packaging platform, and the insertion loss test device are fixed on the same platform, the packaging platform is fixed on the left side of the coupling platform, and the insertion loss test device is fixed on the right side of the coupling platform.

[0006] Preferably, in step 1), the end face of the optical fiber array is stripped using automatic laser to improve the consistency of the optical fiber and stabilize the fiber height difference during packaging.

[0007] Preferably, in step 1), the cleanliness of the optical fiber end face reaches no dirt or scratches at a magnification of 200X.

[0008] Preferably, the insertion loss of the coupling in step 4) is controlled within 1 dB.

[0009] Compared with the prior art, the present invention has the following advantages: 1. In terms of structural design, compared with the traditional manual coupling method, the present invention concentrates the entire coupling-packaging-testing process on the same platform, which improves the repeatability and stability of product manufacturing; the insertion loss changes during the coupling process are observed in real time to adjust the platform structure, and the coupling platform accessories are selected according to the characteristics of the product. The optical fiber array coupling of various silicon-based optical waveguide products can be performed without changing the platform; 2. In terms of coupling packaging, the cleanliness of the high-precision polished fiber array end face can reach 200X magnification without dirt and scratches. The fiber spacing of each channel is less than 10μm, which solves the problem of coupling interference between fiber arrays. Automatic laser fiber stripping is used to improve the consistency of the fiber and stabilize the fiber height difference during packaging. During the coupling process, the insertion loss is controlled within 1dB before packaging and dispensing curing, avoiding the risk of turnover contamination during product production; 3. In terms of optical applications, multi-port coupled silicon photonic products can be used to make optical waveguide splitter chips after optimizing coupling insertion loss and packaging stability, and can be used in dense wavelength division multiplexers on backbone networks and communication trunk lines, as well as fiber-to-the-home access network technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram of the coupling-packaging-testing platform structure of the present invention; In the figure: A-coupling platform, B-packaging platform, C-insertion loss test equipment. DETAILED DESCRIPTION

[0011] The technical solution of the present invention is described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0012] like Figure 1 As shown, a method for coupling a silicon-based optical waveguide to an optical fiber array, the specific steps are as follows: 1) Use auxiliary polishing MT ferrule to perform high-precision polishing on the end face of the optical fiber array, clean and inspect the coupling surface, and ensure that the distance tolerance of the optical fiber end face is less than 10μm; 2) Debug the coupling platform A and adjust the component positions and parameters of the platform according to the optical fiber array structure to be coupled; 3) Debug packaging platform B, adjust the platform tooling through the coupling surface structure that needs to be packaged to ensure the stability of packaging curing; 4) Debug the insertion loss test equipment C, complete the optical path connection of the insertion loss equipment according to the signal loop of the optical waveguide, observe the insertion loss of the coupling in real time, adjust the coupling platform according to the loss change, perform glue dispensing and packaging curing after meeting the standard, and monitor the insertion loss globally; 5) Complete coupling-packaging-testing and remove the finished product from the platform.

[0013] Furthermore, the coupling platform, packaging platform, and insertion loss test equipment are fixed on the same platform, the packaging platform is fixed on the left side of the coupling platform, and the insertion loss test equipment is fixed on the right side of the coupling platform.

[0014] Furthermore, in step 1), the end face of the optical fiber array is automatically laser stripped to improve the consistency of the optical fiber and stabilize the fiber height difference during packaging.

[0015] Furthermore, in the step 1), the cleanliness of the optical fiber end face reaches no dirt or scratches at a magnification of 200X.

[0016] Furthermore, the insertion loss of the coupling in step 4) is controlled within 1 dB.

[0017] By using the method described in the present invention to couple the silicon-based optical waveguide with the optical fiber array, the end face precision of the optical fiber array can be improved to 10 μm through a high-precision grinding process, and a platform for the docking, coupling and packaging of the silicon optical waveguide chip and the optical fiber array that can be monitored and adjusted in real time is provided. The equipment parameters of each link are adjusted according to the coupling loss displayed by the power meter, and the loss of each process in the packaging stage is adjusted to the minimum, ensuring the controllability and efficiency of the silicon-based optical waveguide coupling packaging process.

[0018] The above descriptions are merely embodiments of the present invention. It should be pointed out that, for those skilled in the art, various changes, modifications, substitutions and variations can be made to these embodiments without departing from the technical principles of the present invention. These changes, modifications, substitutions and variations should also be regarded as the scope of protection of the present invention.

Claims

1. A method for coupling a silicon-based optical waveguide to an optical fiber array, characterized in that: The specific steps are as follows: 1) Use auxiliary polishing MT ferrule to perform high-precision polishing on the end face of the optical fiber array, clean and inspect the coupling surface, and ensure that the distance tolerance of the optical fiber end face is less than 10μm; 2) Debug the coupling platform and adjust the component positions and parameters of the platform according to the fiber array structure to be coupled; 3) Debug the packaging platform and adjust the platform tooling through the coupling surface structure that needs to be packaged to ensure the stability of packaging curing; 4) Debug the insertion loss test equipment, complete the optical path connection of the insertion loss equipment according to the signal loop of the optical waveguide, observe the insertion loss of the coupling in real time, adjust the coupling platform according to the loss change, perform glue dispensing and packaging curing after meeting the standard, and monitor the insertion loss globally; 5) Complete coupling-packaging-testing and remove the finished product from the platform.

2. The method for coupling a silicon-based optical waveguide to an optical fiber array according to claim 1, characterized in that: The coupling platform, packaging platform, and insertion loss test equipment are fixed on the same platform, the packaging platform is fixed on the left side of the coupling platform, and the insertion loss test equipment is fixed on the right side of the coupling platform.

3. The method for coupling a silicon-based optical waveguide to an optical fiber array according to claim 1, characterized in that: In the step 1), the end face of the optical fiber array is stripped by automatic laser, which improves the consistency of the optical fiber and stabilizes the fiber height difference during packaging.

4. The method for coupling a silicon-based optical waveguide to an optical fiber array according to claim 1, characterized in that: In the step 1), the cleanliness of the optical fiber end face reaches no dirt or scratches at a magnification of 200X.

5. The method for coupling a silicon-based optical waveguide to an optical fiber array according to claim 1, characterized in that: The insertion loss of coupling in step 4) is controlled within 1 dB.

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