A high-quality fiber array for CPO silicon photonic engines

Abstract

This utility model relates to a high-quality fiber array for CPO silicon photonics engines. Multiple bare optical fibers are positioned within V-grooves formed on the upper surface of a substrate. A cover plate is bonded and fixed to the upper surface of the substrate, covering the bare optical fibers. An upper notch penetrating its lower surface and two sides is formed on the optical end of the cover plate. A lower notch penetrating its upper surface and two sides is formed on the optical end of the substrate below the bare optical fibers. The depth of both the upper and lower notches is 0.25mm ± 0.05mm. The distance between the bare optical fiber and the upper surface of the upper notch, and the distance between the bare optical fiber and the lower surface of the lower notch, are both 0.04mm ± 0.01mm. The upper and lower notches are filled with hard adhesive. The advantages are: during polishing of the optical end, the adhesive delamination rate can be significantly reduced, ensuring long-term reliability; the equal thickness of the adhesive layers on the upper and lower parts of the bare optical fiber can offset the thermal expansion of the adhesive, preventing increased insertion loss.

Description

Technical Field

[0001] This utility model relates to the field of CPO silicon photonics engine technology, specifically to a high-quality fiber array for CPO silicon photonics engines. Background Technology

[0002] Traditional CPO silicon photonic engines generally require high-quality fiber arrays with no delamination. These fiber arrays typically have at least 8 channels or more, and their structure is as follows: Figure 1 , Figure 2 As shown, the fiber optic array includes a substrate, a cover plate, and multiple optical fibers. Multiple V-grooves, arranged in rows, are formed on the upper surface of the substrate. The number of V-grooves is at least eight. One end of each V-groove penetrates the optical end of the substrate, while the other end extends towards the tail end. The bare optical fibers are positioned within the V-grooves formed on the upper surface of the substrate. The cover plate is bonded to the upper surface of the substrate and covers the bare optical fibers. The adhesive layer between the cover plate and the upper surface of the substrate is typically 0.05 mm thick. The adhesive used to bond the cover plate and the substrate is a hard adhesive. The bare optical fibers are in direct contact with the cover plate, and the adhesive layer thickness at the contact point is close to 0 μm. Because the adhesive layer thickness at the contact point between the bare optical fibers and the cover plate is close to 0 μm, the local bonding force is small, and the point contact resistance to abrasion thermal stress is poor. This makes it easy for the adhesive to delaminate within 50 μm of the optical end of the fiber optic array during abrasion, thus affecting the long-term reliability of the fiber optic array. Utility Model Content

[0003] The technical problem to be solved by this invention is to provide a high-quality fiber array for CPO silicon photonic engines, so as to overcome the shortcomings of the prior art.

[0004] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A high-quality fiber array for a CPO silicon photonics engine includes: a substrate, a cover plate, and multiple optical fibers. The bare optical fibers of the multiple optical fibers are respectively located in V-grooves opened on the upper surface of the substrate. The cover plate is bonded and fixed to the upper surface of the substrate and covers the bare optical fibers. An upper notch is opened on the optical end of the cover plate, penetrating its lower surface and two sides. A lower notch is opened on the optical end of the substrate, below the bare optical fibers, penetrating its upper surface and two sides. The depth of both the upper and lower notches is 0.25mm ± 0.05mm. The distance between the bare optical fibers and the upper surface of the upper notch and the lower surface of the lower notch is 0.04mm ± 0.01mm. The upper and lower notches are filled with rigid adhesive for bonding and fixing the substrate, bare optical fibers, and cover plate.

[0005] Based on the above technical solution, the present invention can be further improved as follows.

[0006] Furthermore, a soft adhesive for optical fiber pigtails is dotted onto the upper surface of the substrate at the tail end of the cover plate.

[0007] Furthermore, the depth of the notch on the smooth end of the cover plate after grinding is 0.15mm ± 0.05mm.

[0008] Furthermore, the depth of the notch at the smooth end of the substrate after grinding is 0.15mm ± 0.05mm.

[0009] Furthermore, the number of V-grooves is at least 8, and the number of optical fibers is at least 8.

[0010] The beneficial effects of this invention are as follows: By creating an upper notch on the optical surface of the cover plate and a lower notch on the optical surface of the substrate below the bare optical fiber, and then filling the upper and lower notches with hard adhesive to bond and fix the substrate, bare optical fiber, and cover plate, a certain thickness of adhesive layer is formed between the bare optical fiber and the substrate, and between the bare optical fiber and the cover plate, thus providing sufficient adhesive strength. This significantly reduces the rate of adhesive failure during subsequent polishing of the optical surface of the fiber array, ensuring the long-term reliability of the fiber array. Furthermore, the reason for choosing a depth of 0.25mm ± 0.05mm for the upper and lower notches is that… If the distance is too large, it will lead to poor upper and lower limit positioning of the bare fiber, resulting in high and low fiber conditions, which will increase the coupling insertion loss. If it is too small, it will not solve the problem of adhesive delamination yield. The reason for setting the distance between the bare fiber and the upper surface of the upper notch to 0.04mm±0.01mm, and the distance between the bare fiber and the lower surface of the lower notch to 0.04mm±0.01mm, is that it can not only solve the adhesive delamination yield problem, but also make the thickness of the upper and lower adhesive layers of the bare fiber equal (i.e., 0.04mm±0.01mm). In this way, at high and low temperatures, it can offset the thermal expansion of the adhesive, so as to avoid fiber core displacement due to the difference in adhesive expansion, which would lead to increased insertion loss. Attached Figure Description

[0011] Figure 1 This is a front view of a fiber optic array in the prior art; Figure 2 This is an end-face view of a fiber optic array in the prior art; Figure 3 This is a front view of the high-quality fiber array for the CPO silicon photonics engine in this invention, without the hard adhesive filling. Figure 4 This is a view of the end face of the high-quality fiber array for the CPO silicon photonics engine in this utility model without rigid adhesive filling. Figure 5 This is a front view of the high-quality fiber array for the CPO silicon photonics engine in this invention; Figure 6 This is an end-face view of the high-quality fiber array used in the CPO silicon photonic engine of this utility model.

[0012] The attached diagram lists the components represented by each number as follows: 1. Substrate, 110, V-groove, 120, lower notch; 2. Cover plate, 210, upper notch; 3. Optical fiber, 310, bare optical fiber; 4. Hard adhesive; 5. Soft adhesive. Detailed Implementation

[0013] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model. Example 1

[0014] like Figures 3-6 As shown, a high-quality fiber array for a CPO silicon photonics engine includes: a substrate 1, a cover plate 2, and multiple optical fibers 3. Multiple V-grooves 110 are arranged in rows on the upper surface of the substrate 1. One end of each V-groove 110 penetrates the optical end of the substrate 1, and the other end extends towards the tail end of the substrate 1. The bare optical fibers 310 of the multiple optical fibers 3 are respectively located within the V-grooves 110 on the upper surface of the substrate 1. The cover plate 2 is bonded and fixed to the upper surface of the substrate 1 and covers the bare optical fibers 310. Typically, the adhesive layer thickness between the cover plate 2 and the upper surface of the substrate 1 is 0.05 mm, and the adhesive used to bond the cover plate 2 and the substrate 1 is a rigid adhesive. The aforementioned details remain consistent with existing technology. A notch 210 penetrating the lower surface and two sides of the optical end of the cover plate 2 is formed, while the bare optical fibers 310 are located on the optical end of the substrate 1. A lower notch 120 is made below position 10, penetrating the upper surface and both sides, so that the end of the bare optical fiber 310 is between the upper notch 210 and the lower notch 120. The depth of the upper notch 210 is 0.25mm±0.05mm, the depth of the lower notch 120 is 0.25mm±0.05mm, the distance between the bare optical fiber 310 and the upper surface of the upper notch 210 is 0.04mm±0.01mm, which can be understood as a height difference of 0.04mm±0.01mm; the distance between the bare optical fiber 310 and the lower surface of the lower notch 120 is also 0.04mm±0.01mm, which can also be understood as a height difference of 0.04mm±0.01mm. Then, the upper notch 210 and the lower notch 120 are filled with hard adhesive 4 to bond and fix the substrate 1, the bare optical fiber 310 and the cover plate 2. By creating an upper notch 210 on the optical surface of the cover plate 2 and a lower notch 120 on the optical surface of the substrate 1 below the bare optical fiber 310, and then filling the upper notch 210 and lower notch 120 with hard adhesive 4 to bond and fix the substrate 1, bare optical fiber 310, and cover plate 2, a certain thickness of adhesive layer is formed between the bare optical fiber 310 and the substrate 1, and between the bare optical fiber 310 and the cover plate 2, thus providing sufficient adhesive strength. This significantly reduces the rate of adhesive failure during subsequent polishing of the optical surface of the fiber array, ensuring the long-term reliability of the fiber array. Furthermore, the depths of the upper notch 210 and lower notch 120 are selected to be 0.25mm ± 0.05mm. The reason is that if the distance is too large, it will lead to poor upper and lower limit positioning of the bare optical fiber 310, resulting in high and low fiber conditions, which will increase the coupling insertion loss. If it is too small, it will not solve the problem of adhesive delamination yield. The reason for setting the distance between the bare optical fiber 310 and the upper surface of the upper notch 210 to 0.04mm±0.01mm, and the distance between the bare optical fiber 310 and the lower surface of the lower notch 120 to 0.04mm±0.01mm, is that it can not only solve the problem of adhesive delamination yield, but also make the thickness of the upper and lower adhesive layers of the bare optical fiber 310 equal (i.e., 0.04mm±0.01mm). In this way, at high and low temperatures, it can offset the thermal expansion of the adhesive, so as to avoid fiber core displacement due to the difference in adhesive expansion, which would lead to increased insertion loss. Example 2

[0015] like Figure 3 , Figure 5 As shown, this embodiment is a further improvement on embodiment 1, as detailed below: On the upper surface of the substrate 1, soft adhesive 5 for the pigtail of the optical fiber 3 is dotted at the tail end of the cover plate 2. The dimensions of the bare optical fiber 310 of the optical fiber 3 remain consistent with the existing technology, that is, the outer diameter of the bare optical fiber 310 is 0.125mm, the outer diameter of the plastic cladding area of ​​the optical fiber 3 is 0.25mm, and the material of the bare optical fiber 310 is quartz glass. Example 3

[0016] like Figure 3 , Figure 5 As shown, this embodiment is a further improvement on embodiment 1 or 2, as detailed below: After grinding, the depth of the upper notch 210 on the smooth end of the cover plate 2 is 0.15mm ± 0.05mm, and the depth of the lower notch 120 on the smooth end of the substrate 1 is 0.15mm ± 0.05mm. This depth cannot be too large, otherwise it will cause poor upper and lower limit of the bare optical fiber 310, resulting in high and low fiber conditions, which will increase the coupling insertion loss. If it is too short, it will not be able to solve the problem of debonding yield. Example 4

[0017] like Figure 4 , Figure 6 As shown, this embodiment is a further improvement on embodiment 1, 2, or 3, as detailed below: The number of V-grooves 110 is at least 8, and the number of optical fibers 3 is at least 8, which can meet the usage requirements of CPO silicon photonics engine.

[0018] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A high quality fiber array for a CPO silicon light engine, comprising: The substrate (1), cover plate (2), and multiple optical fibers (3) are provided. The bare optical fibers (310) of the multiple optical fibers (3) are respectively located in the V-grooves (110) opened on the upper surface of the substrate (1). The cover plate (2) is bonded and fixed to the upper surface of the substrate (1) and covers the bare optical fibers (310) of the optical fibers (3). The cover plate (2) has an upper notch (210) that penetrates its lower surface and two sides on its optical end. The substrate (1) has a through-hole at a position below the bare optical fiber (310) on its optical end. The upper surface and the two sides of the upper notch (210) are both 0.25mm ± 0.05mm deep. The distance between the bare optical fiber (310) and the upper surface of the upper notch (210) and the distance between the bare optical fiber (310) and the lower surface of the lower notch (120) are both 0.04mm ± 0.01mm. The upper notch (210) and the lower notch (120) are filled with hard glue (4) for bonding and fixing the substrate (1), the bare optical fiber (310) and the cover plate (2).

2. A high quality fiber array for a CPO silicon light engine according to claim 1, wherein, On the upper surface of the substrate (1), soft adhesive (5) of the fiber (3) pigtail is dotted at the tail end of the cover plate (2).

3. A high quality fiber array for a CPO silicon light engine according to claim 1, wherein, The depth of the notch (210) on the smooth end of the cover plate (2) after grinding is 0.15mm ± 0.05mm.

4. A high quality fiber array for a CPO silicon light engine according to claim 1, wherein, The depth of the notch (120) on the smooth end of the substrate (1) after grinding is 0.15mm ± 0.05mm.

5. A high quality fiber array for a CPO silicon light engine according to any one of claims 1 to 4, characterized in that, The number of V-grooves (110) is at least 8, and the number of optical fibers (3) is at least 8.

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