CN214895887U

CN214895887U - Integrated PLC chip capable of simultaneously realizing multichannel optical signal transmission and monitoring functions

Info

Publication number: CN214895887U
Application number: CN202120549073.1U
Authority: CN
Inventors: 尹小杰; 郑之远; 訾辛壮; 孙静雯; 郜飞飞; 赵青
Original assignee: HENAN SHIJIA PHOTONS TECHNOLOGY CO LTD
Current assignee: HENAN SHIJIA PHOTONS TECHNOLOGY CO LTD
Priority date: 2021-03-17
Filing date: 2021-03-17
Publication date: 2021-11-26
Anticipated expiration: 2031-03-17

Abstract

The utility model provides an integrated PLC chip of realizing multichannel optical signal transmission and monitoring function simultaneously for solve among the prior art that the passive optical network transmission technique of fiber to the home can't be simple, quick and the problem that the integration realizes multichannel optical signal transmission and passageway control and uses simultaneously. The utility model discloses constitute by upper cladding, waveguide sandwich layer and wafer basement. The waveguide core layer is positioned on the upper part of the wafer substrate, and the upper cladding layer is positioned on the upper part of the wafer substrate and covers the waveguide core layer; the waveguide core layer comprises a waveguide grating and a planar waveguide optical splitter, the output end of the planar waveguide optical splitter is connected with the waveguide grating, and the period of the waveguide grating is uniform. The utility model discloses set up waveguide grating and optical divider on same PLC chip, waveguide grating has the filtering action, has realized carrying out the purpose of multichannel optical signal transmission and passageway control simultaneously, and has reduced the complexity of passageway control, has improved stability and reliability, possesses wide application and worth.

Description

Integrated PLC chip capable of simultaneously realizing multichannel optical signal transmission and monitoring functions

Technical Field

The utility model relates to a fiber to the home passive optical network technical field especially relates to an integrated PLC chip who realizes multichannel optical signal transmission and monitoring function simultaneously.

Background

Under the current big background of three networks big integration, speed increase and cost reduction become important strategic engineering for broadband network construction. The Fiber To The Home (FTTH) Passive Optical Network (PON) technology has been rapidly developed by virtue of its advantages of ultra-high bandwidth, flexible networking, etc., and thus becomes a mainstream technical solution for the current broadband network construction.

In order to realize the network information transmission of ultra-high bandwidth and multi-channel, the passive optical splitter is widely applied and developed, and the optical splitter is one of the main optical devices for realizing optical signal splitting, optical signal power distribution and coupling control as a core device for connecting an optical network terminal and an optical network unit. The Y-branch waveguide structure is an important and most commonly used optical branching waveguide device in integrated optics, and is widely applied to integrated optical devices such as optical modulators, optical switches, mach-zehnder interferometers and the like due to the advantages of simple structure, uniform light splitting, small influence of extra loss on the device and the like.

The appearance of the optical splitter realizes multi-channel network information transmission, but the state monitoring of a complex network terminal has not been greatly developed. At present, network monitoring is mainly to monitor network transmission signals in a chip by using a monitoring mechanism that a multichannel output signal is connected with the outside and is relatively complex, the structure is relatively complex, special research on a network link state monitoring technology in a fiber-to-the-home network structure is very few, and the effect of simultaneously carrying out multichannel optical signal transmission and channel monitoring cannot be achieved.

SUMMERY OF THE UTILITY MODEL

To foretell technical problem, the utility model provides an realize multichannel optical signal transmission and monitor function's integrated PLC chip simultaneously, with planar waveguide optical divider and waveguide grating integrated design on same optical chip for solve among the prior art the unable simple, quick and integrated realization multichannel optical signal transmission and the passageway control problem of using of fiber to the home network transmission technique, reduce the complexity of network link control, reduce the parallel realization degree of difficulty of whole optical network structure transmission and control by a wide margin.

In order to achieve the above purpose, the technical solution of the present invention is realized as follows:

an integrated PLC chip for simultaneously realizing the functions of multi-channel optical signal transmission and monitoring is composed of an upper cladding layer, a waveguide core layer and a wafer substrate. The waveguide core layer is positioned on the upper part of the wafer substrate, and the upper cladding layer is positioned on the upper part of the wafer substrate and covers the waveguide core layer; the waveguide core layer comprises a waveguide grating and a planar waveguide optical splitter, the output end of the planar waveguide optical splitter is connected with the waveguide grating, and the period of the waveguide grating is uniform.

Furthermore, the wafer substrate is silicon-based or quartz-based, the waveguide core layer is silicon dioxide doped with germanium, the upper cladding layer is silicon dioxide doped with boron and phosphorus, the refractive index of the waveguide core layer is larger than that of the wafer substrate and the upper cladding layer, and the refractive index of the waveguide grating region in the waveguide core layer is changed periodically.

Furthermore, the waveguide grating is a waveguide grating which adopts a semiconductor deep etching process.

Further, the waveguide grating is a bragg waveguide grating.

Furthermore, the waveguide core layer also comprises a capillary tube, and the capillary tube is connected with the input end of the planar waveguide optical splitter.

Further, the planar waveguide optical splitter includes n levels of Y-branch waveguides arranged in a tree-like branch arrangement and connected in sequence.

Furthermore, the input end of a first-level Y-branch waveguide in the n levels of Y-branch waveguides is connected with the capillary, and the output end of the first-level Y-branch waveguide is connected with the input end of a second-level Y-branch waveguide; the input end of the nth level Y-branch waveguide is connected with the input end of the (n-1) th level Y-branch waveguide, and the output end of the nth level Y-branch waveguide is connected with the waveguide grating.

Further, the structure of each Y-branch waveguide of the n levels of Y-branch waveguides is the same.

Furthermore, each Y-branch waveguide in the n levels of Y-branch waveguides comprises an input waveguide and an output waveguide, and the input waveguide and the output waveguide are sequentially connected in a front-back manner.

Further, the input waveguides include a wide straight input waveguide, a narrow straight input waveguide, a widened waveguide and a transition waveguide; the wide straight input waveguide, the narrow straight input waveguide, the widening waveguide and the transition waveguide are sequentially connected in front and back, and the transition waveguide is connected with the output waveguide.

The utility model integrates and designs the planar waveguide light splitter and the waveguide grating on the same optical chip, firstly, the problem that the multichannel optical signal transmission and the network link state can not be simultaneously realized in the fiber-to-the-home passive optical network technology is solved; secondly, an external monitoring mechanism is not required to be connected, so that the complexity of network link monitoring is reduced; thirdly, the stability and the reliability in the using process are improved, good performance parameters are provided, and more channels can be flexibly expanded; and fourthly, the method is suitable for mass production in modern industry and can be widely applied to fiber-to-the-home construction and other optical network transmission.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic cross-sectional structure diagram of an input terminal of an integrated PLC chip according to the present invention;

fig. 2 is a schematic structural diagram of a waveguide core layer in the integrated PLC chip according to the present invention;

fig. 3 is a schematic structural diagram of a waveguide grating in the integrated PLC chip of the present invention;

fig. 4 is a schematic cross-sectional structure diagram of an output end of the integrated PLC chip of the present invention;

fig. 5 is a schematic structural diagram of a Y-branch waveguide in the integrated PLC chip of the present invention;

fig. 6 is a spectrogram diagram of the integrated PLC chip according to the second embodiment of the present invention, in which (a) is a reflection spectrogram diagram, and (b) is a transmission spectrogram diagram.

In the figure: 1-upper cladding, 2-waveguide core layer, 3-wafer substrate, 4-waveguide grating, 5-planar waveguide optical splitter, 6-capillary, 7-first level Y-branch waveguide, 8-second level Y-branch waveguide, 9-nth-1 level Y-branch waveguide, 10-nth level Y-branch waveguide, 11-input waveguide, 12-output waveguide, 13-wide straight input waveguide, 14-narrow straight input waveguide, 15-broadened waveguide, and 16-transition waveguide.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without any creative effort belong to the protection scope of the present invention.

Embodiment 1, as shown in fig. 1, the present invention provides an integrated PLC chip capable of simultaneously implementing multichannel optical signal transmission and monitoring functions, including an upper cladding layer 1, a waveguide core layer 2 and a wafer substrate 3, wherein the waveguide core layer 2 is located on the wafer substrate 3, the upper cladding layer 1 is located on the wafer substrate 3 and covers the waveguide core layer 2, in this embodiment, the cross section of the upper cladding layer 1 is an inverted concave shape, the cross section of the waveguide core layer 2 and the cross section of the wafer substrate 3 are both rectangular, the lower surface of the waveguide core layer 2 contacts with the upper surface of the wafer substrate 3, the upper, left and right three surfaces of the waveguide core layer 2 correspondingly contact with the upper, left and right three surfaces of the inner groove of the upper cladding layer 1, so that the upper cladding layer 1 covers the waveguide core layer 2, in other embodiments of the present invention, the upper cladding layer 1, the waveguide core layer 2 and the wafer substrate 3 can be in other shapes, and satisfies the above positional relationship.

As shown in fig. 2, the waveguide core layer 2 includes a waveguide grating 4 and a planar waveguide optical splitter 5, an output end of the planar waveguide optical splitter 5 is connected to the waveguide grating 4, and as shown in fig. 3, a period of the waveguide grating 4 is uniform, wherein in this embodiment, the waveguide grating 4 and the planar waveguide optical splitter 5 are disposed on the same PLC chip, and when an optical signal is input to the PLC chip of this embodiment, the optical signal is divided into a plurality of parts by the planar waveguide optical splitter as needed, so as to achieve a purpose of multi-channel optical signal transmission; meanwhile, because the output end of the planar waveguide optical branching unit 5 is connected with the waveguide grating 4, a plurality of optical signals can be output to the waveguide grating 4 from the planar waveguide optical branching unit 5, the period of the waveguide grating 4 is uniform, the optical signals with specific wavelength are reflected, the filtering effect is achieved, and the purpose of monitoring the state of a network link is achieved; in addition, in the embodiment, the PLC chip does not need an external connection monitoring mechanism, so that the complexity of network link monitoring is reduced, the stability and the reliability in the use process are improved, the PLC chip is suitable for mass production of modern industry, and the PLC chip can be widely applied to fiber-to-the-home construction and other optical network transmission.

Further, in this embodiment, the wafer substrate 3 is a quartz substrate, the waveguide core layer 2 is silica doped with germanium, the upper cladding layer 1 is silica doped with boron and phosphorus, and the refractive index of the waveguide core layer 2 is 1.4651-1.4811 and is larger than the refractive index 1.4448 of the wafer substrate 3 and the refractive index 1.4448 of the upper cladding layer 1 by adjusting the concentration of germanium in the silica of the waveguide core layer 2 and the concentrations of boron and phosphorus in the silica of the upper cladding layer 1, at this time, the refractive index of the waveguide grating 4 region in the waveguide core layer 2 periodically changes, so that the waveguide grating 4 has a filtering function, can reflect a specific wavelength, and the PLC chip has a monitoring capability of a network link state by using the characteristic of the waveguide grating 4.

Further, in the present embodiment, the waveguide grating 4 is a waveguide grating using a semiconductor deep etching process. The semiconductor deep etching process includes exposing waveguide grating image designed in the mask plate on the wafer substrate with the mask plate and photoetching machine to obtain required waveguide grating image, and deep etching with the semiconductor etching machine to obtain corresponding waveguide grating structure. The waveguide grating manufactured by using the semiconductor deep etching process has low cost and little environmental pollution, and is suitable for industrial production.

Further, in the present embodiment, the waveguide grating 4 is a bragg waveguide grating. The bragg grating, also called as a reflection grating, can reflect light with a certain wavelength in incident light according to different design parameters, and has the characteristics of narrow reflection spectral line width and high reflectivity, and the expression of a reflection equation is as follows:

mλ_B＝2Λn_eff

where m is the order of the reflection grating, Λ is the period of the grating, n_effIs the effective refractive index of the core region, λ_BIs the reflected wavelength.

Further, as shown in fig. 2, in the present embodiment, the waveguide core layer 2 further includes a capillary 6, and the capillary 6 is connected to the input end of the planar waveguide optical splitter 5. The capillary 6 is used for inputting the transmitted optical signal into the planar waveguide optical splitter 5, which is a common method, and can be matched with a mature production process in production, thereby being beneficial to large-scale production. Other similar structures may be used in other embodiments of the present invention.

Further, in the present embodiment, the planar waveguide splitter 5 includes n levels of Y-branch waveguides arranged in a tree-like branch arrangement and connected in sequence. As shown in FIG. 4, in the production process, the number of n is adjusted to flexibly control the number of channels 2 in the transmission process of the multi-channel optical signalⁿFurther controlling the number of parts of the optical signal transmitted into the waveguide grating 4, and adapting to more application fieldsAnd (5) landscape.

Further, in the present embodiment, the input end of the first-level Y-branch waveguide 7 among the n levels of Y-branch waveguides is connected to the capillary 6, and the output end of the first-level Y-branch waveguide 7 is connected to the input end of the second-level Y-branch waveguide 8; the input end of the nth level Y-branch waveguide 10 is connected with the input end of the (n-1) th level Y-branch waveguide 9, and the output end of the nth level Y-branch waveguide 10 is connected with the waveguide grating 4.

Further, in the present embodiment, the structure of each of the n levels of Y-branch waveguides is the same. Therefore, the complexity of the PLC chip structure can be reduced, the production speed is increased, and the PLC chip structure is more suitable for the production environment of modern industry.

Further, as shown in fig. 5, in the present embodiment, each of the n levels of Y-branch waveguides includes an input waveguide 11 and an output waveguide 12, and the input waveguide 11 and the output waveguide 12 are connected. When the PLC chip works, an optical signal enters from the capillary 6, enters from the input waveguide 11 of the first-level Y-branch waveguide 7 to the output waveguide 12, enters from the output waveguide 12 to the input waveguide 11 of the next-level Y-branch waveguide, and finally enters into the waveguide grating 4 from the output waveguide 12 of the nth-level Y-branch waveguide 10.

Further, as shown in fig. 5, in the present embodiment, the input waveguide 11 includes a wide straight input waveguide 13, a narrow straight input waveguide 14, a widened waveguide 15, and a transition waveguide 16; the wide straight input waveguide 13, the narrow straight input waveguide 14, the widening waveguide 15 and the transition waveguide 16 are sequentially connected from front to back, the transition waveguide 16 is connected with the output waveguide 12 of the Y-branch waveguide of the current level, and the wide straight input waveguide 13 is connected with the capillary 6 or the output waveguide 12 of the Y-branch waveguide of the previous level. Specifically, the cross section of the wide straight input waveguide 13 is fixed, and an optical signal is input from the input end of the wide straight input waveguide 13; the cross section of the narrow straight input waveguide 14 is fixed and smaller than that of the wide straight input waveguide 13, and the input end of the narrow straight input waveguide 14 is connected with the output end of the wide straight input waveguide 13; the input end of the widening waveguide 15 is connected with the output end of the narrow straight input waveguide 14, the cross section of the input end of the widening waveguide 15 is the same as that of the output end of the narrow straight input waveguide 14, and the cross section of the input end of the widening waveguide 15 gradually increases from the input end to the output end; the cross section of the transition waveguide 16 is the same as that of the output end of the widening waveguide 15, the input end of the transition waveguide 16 is connected with the output end of the widening waveguide 15, and the output end of the transition waveguide 16 is connected with the input end of the output waveguide 12. In the embodiment, the narrow straight input waveguide 14 can effectively filter the high-order mode generated in the output wide waveguide 13 of the Y-branch structure of the previous level, so as to improve the uniformity of the device output; meanwhile, a broadening waveguide 15 is also introduced into the Y-shaped branch waveguide structure, so that the influence of the tilt effect on the tail end of the optical field mode can be reduced, the broadening of the light beam passing through the broadening waveguide 15 can be slowly changed, and the transition waveguide 16 enables the changed broadening light beam to tend to be stable.

Embodiment 2 is an integrated PLC chip that simultaneously implements a multi-channel optical signal transmission and monitoring function, and is different from embodiment 1 in that the PLC chip is a 1 × 8 optical splitter integrated chip. In order to better match the existing mature production process and adapt to mass production, in the planar waveguide light splitter 5, the cross section of each waveguide is 6um × 6um, the lengths of the input waveguide 11, the widening waveguide 15 and the transition waveguide 16 are 3300um, 500um and 90um respectively, the level of the preset Y waveguide branch is 3, in the waveguide grating 4, the grating length is 8000um, the grating duty ratio is 50%, and the reflection order of the fixed waveguide grating is 9 orders. The wafer substrate 3 is silicon-based, the concentration of germanium in silica of the waveguide core layer 2 and the concentrations of boron and phosphorus in silica of the upper cladding layer 1 are preset, when an optical signal with the wavelength of 1550nm is input, the refractive index is 1.4447, the refractive index of the waveguide core layer 2 is 1.4556, and the refractive index of the upper cladding layer 1 is 1.4447. The above parameters are only used in this embodiment, and other parameters meeting the standard can be used in other embodiments of the present invention as long as the purpose is achieved.

Further, in this embodiment, the integrated PLC chip to be manufactured is coupled and packaged, and an experimental platform is built by using a broadband light source, a circulator, a spectrum analyzer, an integrated optical chip and a plurality of single-mode optical fiber jumpers, so as to perform performance research on the integrated PLC chip device. The test result is shown in fig. 6 (a) and (b), the reflection range of the manufactured integrated PLC chip device is 1597nm to 1639nm, the center wavelength interval of adjacent channels is 6nm, the 3dB bandwidth is 0.67nm at most, the channel reflectivity is 88.24% at least, the average insertion loss in the transmission process of an 8-channel optical signal is 11.92dB, and the output uniformity is 0.19 dB.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides an integrated PLC chip of realizing multichannel optical signal transmission and monitoring function simultaneously, comprises upper cladding (1), waveguide sandwich layer (2) and wafer substrate (3), its characterized in that: the waveguide core layer (2) is positioned on the upper part of the wafer substrate (3), and the upper cladding layer (1) is positioned on the upper part of the wafer substrate (3) and covers the waveguide core layer (2); the waveguide core layer (2) comprises a waveguide grating (4) and a planar waveguide optical splitter (5), the output end of the planar waveguide optical splitter (5) is connected with the waveguide grating (4), and the period of the waveguide grating (4) is uniform.

2. The integrated PLC chip according to claim 1, wherein the integrated PLC chip is capable of simultaneously performing a multi-channel optical signal transmission and monitoring function, and comprises: the wafer substrate (3) is made of a silicon substrate or a quartz substrate, the waveguide core layer (2) is made of silicon dioxide doped with germanium, the upper cladding layer (1) is made of silicon dioxide doped with boron and phosphorus, the refractive index of the waveguide core layer (2) is larger than that of the wafer substrate (3) and the upper cladding layer (1), and the refractive index of a waveguide grating (4) area in the waveguide core layer (2) changes periodically.

3. The integrated PLC chip according to claim 1 or 2, wherein the integrated PLC chip is capable of simultaneously performing a multichannel optical signal transmission and monitoring function, and comprises: the waveguide grating (4) is a waveguide grating adopting a semiconductor deep etching process.

4. The integrated PLC chip according to claim 3, wherein the integrated PLC chip is further configured to perform a multi-channel optical signal transmission and monitoring function: the waveguide grating (4) is a bragg waveguide grating.

5. The integrated PLC chip for simultaneously realizing the transmission and monitoring functions of the multi-channel optical signal according to claim 4, wherein: the waveguide core layer (2) further comprises a capillary tube (6), and the capillary tube (6) is connected with the input end of the planar waveguide optical splitter (5).

6. The integrated PLC chip according to claim 5, wherein the integrated PLC chip is further configured to perform a multi-channel optical signal transmission and monitoring function: the planar waveguide light branching device (5) comprises n levels of Y-branch waveguides which are arranged in a tree-shaped branch manner and are connected in sequence.

7. The integrated PLC chip according to claim 6, wherein the integrated PLC chip is capable of simultaneously performing a multi-channel optical signal transmission and monitoring function, and comprises: the input end of a first-level Y-branch waveguide (7) in the n levels of Y-branch waveguides is connected with the capillary (6), and the output end of the first-level Y-branch waveguide (7) is connected with the input end of a second-level Y-branch waveguide (8); the input end of the nth-level Y-branch waveguide (10) is connected with the input end of the (n-1) th-level Y-branch waveguide (9), and the output end of the nth-level Y-branch waveguide (10) is connected with the waveguide grating (4).

8. The integrated PLC chip according to claim 7, wherein the integrated PLC chip is capable of simultaneously performing a multi-channel optical signal transmission and monitoring function, and comprises: the structure of each of the n levels of Y-branch waveguides is the same.

9. The integrated PLC chip according to claim 8, wherein: each Y-branch waveguide of the n levels of Y-branch waveguides comprises an input waveguide (11) and an output waveguide (12), and the input waveguide (11) and the output waveguide (12) are sequentially connected in a front-back mode.

10. The integrated PLC chip according to claim 9, wherein: the input waveguide (11) comprises a wide straight input waveguide (13), a narrow straight input waveguide (14), a widening waveguide (15) and a transition waveguide (16); the wide straight input waveguide (13), the narrow straight input waveguide (14), the widening waveguide (15) and the transition waveguide (16) are sequentially connected in front and back, and the transition waveguide (16) is connected with the output waveguide (12).