CN116719181A - Grating type electro-optic adjustable filter with waveguide structure directly formed by metal bottom electrode - Google Patents
Grating type electro-optic adjustable filter with waveguide structure directly formed by metal bottom electrode Download PDFInfo
- Publication number
- CN116719181A CN116719181A CN202310776597.8A CN202310776597A CN116719181A CN 116719181 A CN116719181 A CN 116719181A CN 202310776597 A CN202310776597 A CN 202310776597A CN 116719181 A CN116719181 A CN 116719181A
- Authority
- CN
- China
- Prior art keywords
- layer
- electro
- waveguide
- core layer
- bottom electrode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 27
- 239000002184 metal Substances 0.000 title claims abstract description 27
- 239000010410 layer Substances 0.000 claims abstract description 114
- 239000012792 core layer Substances 0.000 claims abstract description 64
- 239000000382 optic material Substances 0.000 claims abstract description 34
- 238000005253 cladding Methods 0.000 claims abstract description 21
- 229920000642 polymer Polymers 0.000 claims abstract description 21
- 239000000758 substrate Substances 0.000 claims abstract description 12
- 230000000694 effects Effects 0.000 claims abstract description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 26
- 239000000463 material Substances 0.000 claims description 24
- 239000000377 silicon dioxide Substances 0.000 claims description 13
- 235000012239 silicon dioxide Nutrition 0.000 claims description 12
- 229910052782 aluminium Inorganic materials 0.000 claims description 8
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 8
- 229920003229 poly(methyl methacrylate) Polymers 0.000 claims description 6
- 239000004926 polymethyl methacrylate Substances 0.000 claims description 6
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 5
- 239000004417 polycarbonate Substances 0.000 claims description 5
- 229920000515 polycarbonate Polymers 0.000 claims description 5
- 229910052710 silicon Inorganic materials 0.000 claims description 5
- 239000010703 silicon Substances 0.000 claims description 5
- 230000005540 biological transmission Effects 0.000 claims description 4
- FEJPWLNPOFOBSP-UHFFFAOYSA-N 2-[4-[(2-chloro-4-nitrophenyl)diazenyl]-n-ethylanilino]ethanol Chemical compound C1=CC(N(CCO)CC)=CC=C1N=NC1=CC=C([N+]([O-])=O)C=C1Cl FEJPWLNPOFOBSP-UHFFFAOYSA-N 0.000 claims description 2
- GHDZRIQTRDZCMV-UHFFFAOYSA-N 2-[n-(2-hydroxyethyl)-4-[(4-nitrophenyl)diazenyl]anilino]ethanol Chemical compound C1=CC(N(CCO)CCO)=CC=C1N=NC1=CC=C([N+]([O-])=O)C=C1 GHDZRIQTRDZCMV-UHFFFAOYSA-N 0.000 claims description 2
- JBRZTFJDHDCESZ-UHFFFAOYSA-N AsGa Chemical compound [As]#[Ga] JBRZTFJDHDCESZ-UHFFFAOYSA-N 0.000 claims description 2
- FOQABOMYTOFLPZ-ISLYRVAYSA-N Disperse Red 1 Chemical compound C1=CC(N(CCO)CC)=CC=C1\N=N\C1=CC=C([N+]([O-])=O)C=C1 FOQABOMYTOFLPZ-ISLYRVAYSA-N 0.000 claims description 2
- 229910001218 Gallium arsenide Inorganic materials 0.000 claims description 2
- GPXJNWSHGFTCBW-UHFFFAOYSA-N Indium phosphide Chemical compound [In]#P GPXJNWSHGFTCBW-UHFFFAOYSA-N 0.000 claims description 2
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 2
- 229910052737 gold Inorganic materials 0.000 claims description 2
- 239000010931 gold Substances 0.000 claims description 2
- 229910052709 silver Inorganic materials 0.000 claims description 2
- 239000004332 silver Substances 0.000 claims description 2
- 125000000751 azo group Chemical group [*]N=N[*] 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 11
- 238000005516 engineering process Methods 0.000 abstract description 5
- 238000002360 preparation method Methods 0.000 abstract description 5
- 230000008569 process Effects 0.000 abstract description 5
- 230000004044 response Effects 0.000 abstract description 3
- 238000001312 dry etching Methods 0.000 abstract description 2
- 238000013007 heat curing Methods 0.000 abstract description 2
- 230000002035 prolonged effect Effects 0.000 abstract description 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 15
- 230000003287 optical effect Effects 0.000 description 10
- 238000001228 spectrum Methods 0.000 description 8
- 230000010287 polarization Effects 0.000 description 7
- 230000005684 electric field Effects 0.000 description 6
- 230000008859 change Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 229920002120 photoresistant polymer Polymers 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 238000004140 cleaning Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 3
- 239000008367 deionised water Substances 0.000 description 3
- 229910021641 deionized water Inorganic materials 0.000 description 3
- 238000001259 photo etching Methods 0.000 description 3
- 229920006254 polymer film Polymers 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000007667 floating Methods 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- 239000003292 glue Substances 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000004528 spin coating Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 229920006125 amorphous polymer Polymers 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000009477 glass transition Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 230000009965 odorless effect Effects 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 238000005316 response function Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000010025 steaming Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 229920006352 transparent thermoplastic Polymers 0.000 description 1
- 238000004506 ultrasonic cleaning Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/03—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on ceramics or electro-optical crystals, e.g. exhibiting Pockels effect or Kerr effect
- G02F1/0305—Constructional arrangements
- G02F1/0316—Electrodes
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
- G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
- G02B6/122—Basic optical elements, e.g. light-guiding paths
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
- G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
- G02B6/122—Basic optical elements, e.g. light-guiding paths
- G02B6/124—Geodesic lenses or integrated gratings
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/03—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on ceramics or electro-optical crystals, e.g. exhibiting Pockels effect or Kerr effect
- G02F1/0327—Operation of the cell; Circuit arrangements
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/03—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on ceramics or electro-optical crystals, e.g. exhibiting Pockels effect or Kerr effect
- G02F1/035—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on ceramics or electro-optical crystals, e.g. exhibiting Pockels effect or Kerr effect in an optical waveguide structure
Landscapes
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Optical Integrated Circuits (AREA)
Abstract
A grating type electro-optical tunable filter directly forming a waveguide structure through a metal bottom electrode belongs to the technical field of functional photon chips. The device consists of a substrate layer, a lower cladding layer, a core layer, a bottom electrode layer and an electro-optic material layer, wherein the core layer, the bottom electrode layer and the electro-optic material layer are positioned on the lower cladding layer together; the core layer is of an inverted ridge structure with central symmetry and consists of a flat plate layer and a ridge layer positioned below the flat plate layer, wherein the ridge layer consists of a single-mode straight waveguide input area, a Bragg grating area and a single-mode straight waveguide output area; the bottom electrode layer is divided into two parts of structures which are symmetrical in center by the ridge layer. The preparation method is simple and convenient, and the waveguide structure can be realized by a metal definition cladding technology without the technical processes of dry etching and the like. Compared with the traditional method, the invention has the advantages that other operations except heat curing are not carried out on the core layer, the effect of the device is stable, the relaxation phenomenon of the polymer electro-optic waveguide chip can be effectively reduced, the service life of the device is prolonged, and compared with the thermo-optic modulation response speed, the bandwidth is higher.
Description
Technical Field
The invention belongs to the technical field of functional photon chips, and particularly relates to a grating type electro-optical tunable filter which directly forms a waveguide structure through a metal bottom electrode.
Background
The adjustable filter is a key optical integrated device in an optical communication system, can be used as a functional node of optical interconnection, optical information interaction and optical signal switching network, and plays an important role in the fields of big data centers, 5G communication, quantum computation and the like. Compared with devices such as a thermo-optical tunable filter, the electro-optical tunable filter has higher response speed, generally in the order of nanoseconds to picoseconds, larger bandwidth, easy photoelectric integration and high requirements in a high-speed optical transmission system. The electro-optic tunable filter mainly relies on the electro-optic effect of nonlinear waveguide materials to achieve its fast response function. However, the current electro-optical tunable filter based on inorganic nonlinear materials cannot meet the bandwidth requirement of a high-speed optical communication network more and more due to the problems of higher cost, complex process, lower electro-optical coefficient and the like. The electro-optical tunable filter based on the electro-optical polymer is more and more concerned by people due to the advantages of high cost performance, simple process, high electro-optical coefficient and the like, and has good market prospect.
Disclosure of Invention
The invention aims to solve the defects of the existing adjustable filter technology and provides a grating type electro-optical adjustable filter with a waveguide structure directly formed by a metal bottom electrode. The device waveguide structure can be directly defined by spin coating the electro-optic material on the bottom electrode pattern, and the electro-optic effect generated after corona polarization of the waveguide material is utilized to realize the electrically-controlled tunable filter function, thereby solving the defects of low tuning efficiency, slow tuning speed and complex preparation flow of the existing tunable filter.
The invention relates to a grating type electro-optical tunable filter which directly forms a waveguide structure through a metal bottom electrode, adopts a coplanar traveling wave electrode, and as shown in a figure 1 (a), the grating type electro-optical tunable filter consists of a substrate layer 1, a lower cladding layer 2, a core layer 3, a bottom electrode layer 4 and an electro-optical material layer 5 from bottom to top, wherein the core layer 3, the bottom electrode layer 4 and the electro-optical material layer 5 are jointly positioned on the lower cladding layer 2; the core layer 3 is of an inverted ridge structure with central symmetry along the light transmission direction, and consists of a flat plate layer and a ridge layer positioned below the flat plate layer, wherein the ridge layer consists of a single-mode straight waveguide input area 10, a Bragg grating area 11 and a single-mode straight waveguide output area 12; the bottom electrode layer 4 consists of waveguide electrode areas positioned at two sides of the ridge layer of the core layer 3 and contact electrode areas 13 exposed in the air at two sides of the electro-optic material layer 5 and used for being contacted with external power leads, the waveguide electrode areas are connected with the contact electrode areas 13 through narrow-strip electrode layers, the waveguide electrode areas are coated between the core layer 3 and the electro-optic material layer 5, and the upper surfaces of the waveguide electrode areas are covered by a flat plate layer of the core layer 3; the thickness of the electro-optic material layer 5 is the same as that of the core layer 3, and the electro-optic material layer 5 is positioned at two sides of the core layer 3 and at the inner side of the contact electrode region 13; as shown in fig. 1 (b) (the core layer 3 and the electro-optic material layer 5 are not shown for ease of viewing), the bottom electrode layer 4 is divided by the ridge layer into a two-part structure that is centrosymmetric.
The bragg grating region 11 is a multi-period grating structure, and one grating period Λ is composed of 1 wide (defining the propagation direction of light as length, and the same horizontal plane direction perpendicular to the propagation direction of light as width) waveguide core layer and 1 narrow waveguide core layer, and the width of the wide waveguide core layer is W as shown in fig. 1 (c) 1 The width of the narrow waveguide core layer is W 2 Tooth depth between the wide waveguide core layer and the narrow waveguide core layer is deltah= (W) 1 -W 2 ) 2 (where core width and tooth depth are equivalent core region a width and tooth depth, equivalent core region a range will be given later).
The cross section of the grating type tunable filter beta which directly forms a waveguide structure through a metal bottom electrode in the figure 1 (a) is shown in the figure 1 (d), and the grating type tunable filter is sequentially composed of a substrate layer 1, a lower cladding layer 2, a core layer 3, a bottom electrode layer 4 and an electro-optic material layer 5 from bottom to top; the core layer 3 has an inverted ridge structure, and takes air as an upper cladding of the core layer 3.
The substrate layer 1 is made of any one of indium phosphide, gallium arsenide and silicon.
The material of the lower cladding layer 2 isSU-8, NOA61, polymethyl methacrylate (PMMA), silicon dioxide (SiO) 2 ) Any one of the following.
The core layer 3 material is a polarized host-guest doped polymer electro-optic material, and the polymer main material is any one of polymethyl methacrylate (PMMA), amorphous Polycarbonate (APC) and EpoClad, epoCore, SU-8; the guest material is a chromophore molecule with electro-optical activity, and is any one of disperse red 1 (DR 1), disperse red 13 (DR 13), disperse red 19 (DR 19), azo tricyanofuran (N-TCF) and AJLS 102; the mass of the chromophore molecule with electro-optical activity is 5-25% of the mass of the core layer 3.
The bottom electrode layer 4 is made of any one of gold, silver and aluminum.
The electro-optic material layer 5 and the core layer 3 are made of the same material.
As shown in fig. 2 (a) and (b), the structural principle of the invention is illustrated by taking a straight waveguide as an example, the structure adopts a mode that a metal bottom electrode directly forms a waveguide structure, the waveguide is formed by an equivalent core layer region a and an equivalent cladding layer region b, the effective refractive index 1 of the waveguide is calculated by an approximation method in Ma Kati, and the transmission conditions of transverse magnetism and transverse electric fundamental modes of the waveguide are analyzed by using an overrunning equation to obtain the refractive indexes N of the equivalent core layer region a and the equivalent cladding layer region b core And N clad The relation of the overall effective refractive index N of the waveguide structure is as follows (Wang C X, zhang D M, zhang X C, et al, bottom-metal-printed thermo-optic waveguide switches based on low-loss fluorinated polycarbonate materials [ J)].Opt.Express,2020,28(14):20773–20784.)：
w is the width of the bottom electrode layer 4, i.e. the width of the equivalent cladding region b is the width of the bottom electrode layer 4, which can be measured by means of an optical microscope; n (N) core And N clad The equivalent refractive index of the equivalent core region a and the equivalent refractive index of the equivalent cladding region b are respectively determined by Ma KatiPerforming calculation by using a back approximation method; n is the overall effective refractive index of the waveguide structure formed directly by the metal bottom electrode. When the order is k 0 When=0, q=1, the equation corresponds to TE mode; when the order is k 0 =1, q=0, and the equation corresponds to TM mode.
The signal light used by the grating type electro-optical tunable filter directly forming the waveguide structure through the metal bottom electrode is from an external laser and is led into the core layer 3 in an end face coupling mode; when an external electric field is applied, voltages are applied to the two electrodes in the electrode structure region D, one end of the electrode is connected with a ground wire, and the other end of the electrode is connected with a positive bias voltage. When the grating type electro-optical tunable filter directly forming the waveguide structure through the metal bottom electrode works, as shown in fig. 1 (b), after signal light is input from a port in an input area 10, a forward propagation mode and a reverse mode are coupled at a Bragg grating area 11, and after the signal light is output from a port in an output area 12, an obvious reflection peak exists in a reflection spectrum; when an applied voltage is applied to the electrode structure region D, the refractive index of the equivalent core region a of the electro-optic waveguide decreases, and after the output from the port in the output region 12, the reflection peak in the reflection spectrum will be blue shifted (shifted in the short wavelength direction).
The forward propagation mode is a mode in which the direction of a generated diffraction wave vector is the same as the direction of an incident wave vector when the wavelength range of the incident light is diffracted from a low wavelength to a high wavelength in sequence; the counter-propagating mode is a mode in which the direction of the generated diffracted wave vector is opposite to the direction of the incident wave vector when the incident light is diffracted in order from the high wavelength to the low wavelength.
Compared with the existing device structure and preparation technology, the invention has the beneficial effects that:
(1) Compared with the existing tunable filter, the preparation method is simple and convenient, and the waveguide structure can be realized by a metal definition cladding technology without the technical processes of dry etching and the like. The technology provides a new development direction for the development of the optical waveguide integrated chip, and has wide market prospect.
(2) Compared with the traditional adjustable filter, the invention adopts the bottom electrode for modulation, and compared with the traditional method, the invention does not carry out other operations except heat curing on the core layer, so that the effect of the device is stable, the relaxation phenomenon of the polymer electro-optic waveguide chip can be effectively reduced, and the service life of the device is prolonged.
(3) Compared with the existing adjustable filter, the bottom electrode of the device manufactured by the invention can not only act on the waveguide cladding defined by the effective refractive index method, but also can apply external voltage to the bottom electrode to regulate and control the device, and has simple and convenient operation and novel structure.
(4) Compared with the existing adjustable filter, the device electrode provided by the invention is not exposed on the surface, and the electrode can be effectively prevented from being damaged during polarization, so that the yield is greatly improved.
(5) Compared with the existing adjustable filter, the device is electro-optic modulation, and has higher response speed and larger bandwidth compared with thermo-optic modulation.
Drawings
FIG. 1 is a schematic diagram of a grating-type electro-optic tunable filter with a waveguide structure formed directly from a metal bottom electrode according to the present invention; wherein figure (a) is a schematic diagram of a three-dimensional structure of a grating tunable filter directly forming a waveguide structure through a metal bottom electrode; fig. b is a top view of a grating tunable filter directly forming a waveguide structure through a metal bottom electrode (the slab layer and electro-optic material layer 5 of the core layer 3 are not shown for ease of viewing); fig. (c) is a top view of the bragg grating region 11 in fig. (b); fig. 1 (a) is a schematic cross-sectional view of the β -plane of the grating tunable filter directly forming the waveguide structure through the metal bottom electrode.
FIG. 2 is a schematic diagram of the approximation in a grating tunable filter application Ma Kati with a waveguide structure directly formed by a metal bottom electrode according to the present invention; FIG. (a) is a cross-sectional view of a waveguide formed directly through a metal bottom electrode; fig. (b) is a three-dimensional structure diagram of an example of a straight waveguide.
FIG. 3 is a schematic view showing the structure of a device according to embodiment 1 of the present invention; FIG. 1 is a schematic cross-sectional view of the device of example 1 taken along the beta plane in FIG. 1 (a); fig. (b) is a top view of example 1 (the core layer 3 and the electro-optic material layer 5 are not shown for ease of viewing).
FIG. 4 is a graph showing the relationship between the applied voltage (0 to +2.5V) applied to the electrode structure region D and the refractive index change of the core layer 3 in example 1 of the present invention.
FIG. 5 is a graph showing the variation of the reflection spectrum of the tunable filter according to the embodiment 1 of the present invention with the applied voltage (0-2.45V) in the wavelength range of 1515-1555 nm;
fig. 6 is a flow chart of the process for preparing the device of example 1 of the present invention.
Detailed Description
The advantages and features of the present invention will become more readily apparent to those skilled in the art from the following detailed description, taken in conjunction with the accompanying drawings, in which embodiments are shown, some but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1:
the substrate layer 1 selected in this example is a silicon substrate having a thickness of 500 μm.
The lower cladding layer 2 selected in this example was silicon dioxide having a thickness of 10. Mu.m.
In this embodiment, the host-guest doped polarized polymer electro-optic material used in the core layer 3 is AJLS102/APC, the chromophore molecule with electro-optic activity is AJLS102, the polymer host material APC (polycarbonate is an amorphous, odorless, nontoxic and transparent thermoplastic polymer), the structural formula of the AJLS102 chromophore is shown in the following formula, and the preparation method and experimental spectrogram are shown in reference (Song R, yick a, steper W h.connectivity-dependency-free in-plane poling for Mach-Zehnder modulator with highly conductive electro-optical polymer J APPLIED PHYSICS LETTERS,2007,90 (19): 3136).
The mass usage of the chromophore molecule AJLS102 powder with electro-optical activity used in the core layer 3 material of the embodiment is 20% of the sum of the mass of the chromophore molecule AJLS102 powder and the mass of the polymer host material APC, the synthesized polarized host-guest doped polymer electro-optical material is AJLS102/APC, and the electro-optical coefficient is 84pm/V.
As shown in fig. 3, the core layer 3 in this embodiment is an inverted ridge structure, and is composed of a flat plate layer and a ridge layer located below the flat plate layer, wherein the total height of the flat plate layer and the ridge layer is 5 μm, and the total width is 54 μm; width W of wide waveguide core layer 1 Width W of narrow waveguide core layer of 12 μm 2 The tooth depth delta h at two sides of the narrow waveguide core layer is 4 mu m; the thickness of the bottom electrode layer 4 and the thickness of the ridge layer are the same as 50nm, the bottom electrode layer 4 is a metal aluminum layer, and the width is 25 mu m; the overall length of the grating-type electro-optic tunable filter was 1000. Mu.m, one grating period Λ was 3.545. Mu.m, the duty cycle was 50%, and the dimensions of the electrode structure area D were 200. Mu.m.times.200. Mu.m. The ridge layer is composed of three parts, namely a single-mode straight waveguide input region 10, a Bragg grating region 11 and a single-mode straight waveguide output region 12, and the lengths of the ridge layer are 181 mu m, 638 mu m and 181 mu m respectively.
The photolithographic plate 8 used in this example is identical to the bottom electrode layer 4 and electrode structure region D to be prepared.
The basic synthesis method of the host-guest doped polarized polymer electro-optic material AJLS102/APC in the embodiment is as follows:
1. 3g of powder of the electro-optically active chromophore molecule AJLS102 was taken and placed in a clean weighing flask, and 40g of Amorphous Polycarbonate (APC) solution was added, the solvent used being tetrahydrofuran, wherein the APC mass was 30% of the total solution.
2. The weighing bottle is wrapped by tinfoil and placed into an ultrasonic cleaner under the condition of avoiding light, and ultrasonic stirring is carried out for 6 hours at the temperature of 45 ℃ to ensure that chromophore molecule AJLS102 powder with electro-optic activity is completely and uniformly dispersed in an APC solution, thus obtaining host-guest doped polymer electro-optic material AJLS102/APC.
The center wavelength of choice in this embodiment is 1550nm.
The refractive index of the core layer 3 material used in this example was 1.54 at 1550nm wavelength.
In this embodiment, when an external electric field is applied through the Rsoft software, the relationship between the external electric field and the change of the refractive index of the host-guest doped polarized polymer electro-optic material AJLS102/APC is simulated, and in fig. 4, the solid line is the simulation result of the Rsoft software, the dotted line is the linear fitting result, and as the applied voltage at the electrode structure region D gradually increases, the refractive index of the polymer electro-optic material in the equivalent core region a decreases in a linear trend, and the slope is about-0.01138. In summary, as the applied voltage is changed in the electrode structure region D, the refractive index change of the electro-optic material in the equivalent core region a can be controlled, and the tunable filter function of the device can be realized.
The tunable filter function of a device manufactured by using host-guest doped polarized polymer electro-optic material AJLS102/APC is simulated by Rsoft software. Simulation is performed on the relation of the reflection peak in the reflection spectrum of the tunable filter along with the change of the applied voltage, and as can be seen from fig. 5, after the wide spectrum light is input, the applied voltage is increased, the refractive index of the electro-optic material in the equivalent core layer region a is gradually reduced due to the electro-optic effect, and the reflection peak of the output reflection spectrum is blue shifted (shifted to the short wavelength direction); when no voltage is applied, the central wavelength of the reflection peak of the reflection spectrum is 1550nm, and the 3dB bandwidth is 2.19nm; when the applied voltage is increased by 1V, the reflection peak of the reflection spectrum is blue-shifted to the short wavelength direction by 12.24nm, namely the tuning efficiency is 12.24nm/V; when a voltage of 2.45V is applied, the center wavelength of the reflection peak is blue shifted by about 30nm, the 3dB bandwidth is 1.69nm, and the 3dB bandwidth is reduced but still greater than 1.6nm.
The steps of the method for preparing the grating type electro-optic tunable filter directly forming the waveguide structure through the metal bottom electrode in the embodiment are shown in fig. 6, and the specific description is as follows:
A. taking monocrystalline silicon as a substrate layer 1, taking a silicon dioxide layer growing on the substrate layer 1 as a lower cladding layer 2, firstly cleaning the surface of silicon dioxide, namely placing the silicon wafer in a beaker filled with acetone solution, ultrasonically cleaning in an ultrasonic machine for 10 minutes, and taking out; then put into a beaker filled with isopropanol solution, and take out after ultrasonic cleaning for 10 minutes in an ultrasonic machine; putting the silicon dioxide into a beaker filled with deionized water, ultrasonically cleaning the silicon dioxide in an ultrasonic machine for 10 minutes, taking out the silicon dioxide, and drying the deionized water on the surface of the silicon dioxide by using a nitrogen gun; finally, placing the mixture in a glassware, and drying the glassware in an oven (150 ℃ for 30 min) to remove the water and organic impurities on the surface of the silicon dioxide;
B. placing the cleaned device in an aluminum steaming table under vacuum degree of 6X10 -3 Under Pa, a current of 37.5mA was applied to evaporate a 60nm thick aluminum layer 6 on the cleaned silica surface.
C. Positive photoresist BP212 was spin-coated on aluminum layer 6 (rotation speed: 3000 rpm, time: 20 seconds), immediately after spin-coating, pre-baked on a hot plate (87 ℃ C., 20 minutes), followed by NaOH solution (NaOH: H) 2 O=3g: 1000g) And washing off surface floating glue to obtain the BP212 film layer 7.
D. Placing the chip with the floating glue removed under a photoetching machine, and performing photoresist removal under the conditions of 20mW/cm 2 After exposure for 3 seconds by a positive photoetching plate 8 with the same pattern as the bottom electrode layer 4 under the irradiation of a mercury ultraviolet lamp with power, post baking (92 ℃ for 15 min) is carried out.
E. Placing the chip after post-baking treatment in NaOH solution (NaOH: H) 2 O=3g: 1000g) Part of the BP212 photoresist is removed by a development process (25 s) leaving the mask structure 9 on the positive-working plate 8.
F. And (3) continuously placing the device in the NaOH solution, removing the aluminum film with the surface without the mask structure, flushing the surface residual substances by using deionized water, placing the device under a photoetching machine again for exposure for 10 seconds, and then flushing the mask structure 9, residual BP212 photoresist and residual substances by using absolute ethyl alcohol to obtain the bottom electrode layer 4.
G. After the electrode structure region D is shielded, a host-guest doped polymer electro-optic material AJLS102/APC (rotating speed: 3000 r/min, time: 20 s) is spin-coated on the device of the prepared bottom electrode layer 4, an initial voltage of 20V is applied between the bottom electrode layers 4 at an initial temperature of 50 ℃, and then the temperature is raised to 125 ℃ at a speed of 10 ℃ per minute (the temperature raising function of an instrument used by the polarized material is carried out). When the temperature reached 100 ℃, the polarization voltage was slowly increased to 100V. When the temperature reaches 125 ℃, the AJLS102/APC film is continuously applied with 100V polarization voltage, the AJLS102/APC film is cooled to room temperature, the polarization can be carried out (the polarization can affect the core layer 3 and the electro-optic material layer 5, the basic principle of the polarization is that the polymer film is heated to the vicinity of the glass transition temperature of the polymer film, the amorphous polymer is changed from the glass state to the high-elastic state, at the moment, a strong external electric field is applied to the polymer film for a certain time, chromophores contained in the polymer are oriented in the direction of the electric field, then the heating is stopped, the film is slowly cooled, the electric field is removed after the temperature is reduced to the vicinity of the room temperature, the chromophores which are completely randomly oriented originally are changed into non-centrosymmetry in the macroscopic statistical sense and are frozen, so that the polarized polymer material shows a second-order nonlinear optical effect when interacted with light, the film formed between the bottom electrode layers 4 and the surface is the core layer 3, and the film formed on the outer side of the bottom electrode layer 4 is the electro-optic material layer 5, and the grating type adjustable filter which directly forms a waveguide structure through the metal bottom electrode is prepared.
Claims (4)
1. A grating type electro-optic tunable filter directly forming a waveguide structure through a metal bottom electrode is characterized in that: the coplanar traveling wave electrode is adopted, and consists of a substrate layer (1), a lower cladding layer (2), a core layer (3), a bottom electrode layer (4) and an electro-optic material layer (5) from bottom to top, wherein the core layer (3), the bottom electrode layer (4) and the electro-optic material layer (5) are positioned on the lower cladding layer (2) together; the core layer (3) is of an inverted ridge structure with central symmetry along the light transmission direction, and consists of a flat plate layer and a ridge layer positioned below the flat plate layer, wherein the ridge layer consists of a single-mode straight waveguide input area (10), a Bragg grating area (11) and a single-mode straight waveguide output area (12); the bottom electrode layer (4) consists of waveguide electrode areas positioned at two sides of the ridge layer of the core layer (3) and contact electrode areas (13) exposed in the air at two sides of the electro-optic material layer (5) and used for being contacted with external power leads, the waveguide electrode areas are connected with the contact electrode areas (13) through narrow strip-shaped electrode layers, the waveguide electrode areas are coated between the core layer (3) and the electro-optic material layer (5), and the upper surfaces of the waveguide electrode areas are covered by the flat plate layer of the core layer (3); the thickness of the electro-optic material layer (5) is the same as that of the core layer (3), and the electro-optic material layer (5) is positioned at both sides of the core layer (3) and at the inner side of the contact electrode region (13); the bottom electrode layer (4) is divided into a two-part structure with central symmetry by the ridge layer, and air is used as an upper cladding of the core layer (3).
2. A kind of as claimed in claim 1The grating type electro-optic tunable filter with the waveguide structure directly formed by the metal bottom electrode is characterized in that: the Bragg grating region (11) is a multi-period grating structure, one grating period lambda consists of 1 wide waveguide core layer and 1 narrow waveguide core layer, and the width of the wide waveguide core layer is W 1 The width of the narrow waveguide core layer is W 2 Tooth depth between the wide waveguide core layer and the narrow waveguide core layer is deltah= (W) 1 -W 2 )/2。
3. A grating-type electro-optic tunable filter directly forming a waveguide structure through a metal bottom electrode as claimed in claim 1, wherein: the material of the substrate layer (1) is any one of indium phosphide, gallium arsenide and silicon; the material of the lower cladding layer (2) is any one of SU-8, NOA61, polymethyl methacrylate and silicon dioxide; the material of the core layer (3) and the electro-optic material layer (5) is polarized host-guest doped polymer electro-optic material, the polymer host material is any one of polymethyl methacrylate, amorphous polycarbonate and EpoClad, epoCore, SU-8, the guest material is any one of disperse red 1, disperse red 13, disperse red 19, azo tricyanofuran and AJLS102 which are provided with electro-optic active chromophore molecules, and the mass of the chromophore molecules with electro-optic activity is 5-25% of the mass of the core layer 3; the material of the bottom electrode layer (4) is any one of gold, silver and aluminum.
4. A grating electro-optic tunable filter directly forming a waveguide structure through a metal bottom electrode as claimed in claim 3, wherein: the substrate layer (1) is a silicon substrate with the thickness of 500 mu m, the lower cladding layer (2) is silicon dioxide with the thickness of 10 mu m, the materials of the core layer (3) and the electro-optic material layer (5) are polarized host-guest doped polymer electro-optic materials which are AJLS102/APC, and the electro-optic coefficient is 84pm/V; the total height of the flat layer and the ridge layer in the core layer (3) is 5 mu m, and the total width is 54 mu m; width W of wide waveguide core layer 1 Width W of narrow waveguide core layer of 12 μm 2 The tooth depth delta h at two sides of the narrow waveguide core layer is 4 mu m; the thickness of the bottom electrode layer (4) and the thickness of the ridge layer are the same as 50nm; the bottom electrode layer (4) is a metal aluminum layer with the width of 25 mu m; grating type electrooptical adjustable filterThe overall length of the device is 1000 μm, one grating period lambda is 3.545 μm, the duty cycle is 50%, and the dimensions of the electrode structure region (13) are 200 μm by 200 μm; the lengths of the ridge layer single mode straight waveguide input region (10), the Bragg grating region (11) and the single mode straight waveguide output region (12) are 181 μm, 638 μm and 181 μm respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310776597.8A CN116719181A (en) | 2023-06-29 | 2023-06-29 | Grating type electro-optic adjustable filter with waveguide structure directly formed by metal bottom electrode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310776597.8A CN116719181A (en) | 2023-06-29 | 2023-06-29 | Grating type electro-optic adjustable filter with waveguide structure directly formed by metal bottom electrode |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116719181A true CN116719181A (en) | 2023-09-08 |
Family
ID=87865968
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310776597.8A Pending CN116719181A (en) | 2023-06-29 | 2023-06-29 | Grating type electro-optic adjustable filter with waveguide structure directly formed by metal bottom electrode |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116719181A (en) |
-
2023
- 2023-06-29 CN CN202310776597.8A patent/CN116719181A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100193219B1 (en) | Passive polarizer | |
| CN106094263B (en) | A kind of period polarized LNOI ridge waveguides and preparation method thereof | |
| CN113625393B (en) | Tunable mode converter and preparation method thereof | |
| Michel et al. | High-performance electro-optic modulators realized with a commercial side-chain DR1-PMMA electro-optic copolymer | |
| US20100098424A1 (en) | Organic Electro-Optic Modulators with Transparent Conducting Electrodes and Related Device Structures | |
| Cai et al. | Performance enhancement of on-chip optical switch and memory using Ge2Sb2Te5 slot-assisted microring resonator | |
| Lee et al. | Optical intensity modulator based on a novel electrooptic polymer incorporating high/spl mu//spl beta/chromophore | |
| Chen et al. | UV curable electro-optic polymer switch based on direct photodefinition technique | |
| Kaino | Waveguide fabrication using organic nonlinear optical materials | |
| CN111522153A (en) | Mach-Zehnder type electro-optic modulator based on material on insulator and preparation method thereof | |
| Liu et al. | Broadband meandered thin-film lithium niobate modulator with ultra-low half-wave voltage | |
| Guo et al. | All-optical control of a single resonance in a graphene-on-silicon nanobeam cavity using thermo-optic effect | |
| CN114296177A (en) | Runway-type micro-ring optical switch based on silicon dioxide/polymer mixed waveguide and preparation method thereof | |
| Yao et al. | Design of thin-film lithium niobate structure for integrated filtering and sensing applications | |
| Jiang et al. | On-chip integrated optical switch based on polymer waveguides | |
| Huang et al. | Exploring a band-edge Bragg grating modulator on a hybrid thin-film lithium niobate platform | |
| Donaldson | Candidate materials and technologies for integrated optics: fast and efficient electro-optic modulation | |
| CN116719181A (en) | Grating type electro-optic adjustable filter with waveguide structure directly formed by metal bottom electrode | |
| CN114153028B (en) | Dual-mode waveguide thermo-optical switch based on MZI structure and preparation method thereof | |
| Singer et al. | Guest-host polymers for nonlinear optics | |
| Rezig et al. | Feasibility of optically controlled integrated Mach–Zehnder device based on Azo dye-doped PMMA thin films | |
| Oh et al. | Integrated-optic focal-spot intensity modulator using electrooptic polymer waveguide | |
| Li et al. | Fabrication and characterization of electro-optic polymer/silicon hybrid MZI for interrogating small signals from an ECG | |
| Bechtel et al. | Low-driving-voltage electro-optic polymer modulators for advanced photonic applications | |
| Irace et al. | Light modulation with silicon devices |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |