WO2005011076A1 - Guide d’ondes nervuré à sélecteurs de mode verticaux à guidage faible - Google Patents

Guide d’ondes nervuré à sélecteurs de mode verticaux à guidage faible Download PDF

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Publication number
WO2005011076A1
WO2005011076A1 PCT/IB2004/002438 IB2004002438W WO2005011076A1 WO 2005011076 A1 WO2005011076 A1 WO 2005011076A1 IB 2004002438 W IB2004002438 W IB 2004002438W WO 2005011076 A1 WO2005011076 A1 WO 2005011076A1
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Prior art keywords
waveguide
ridge
optical device
vertical
gratings
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PCT/IB2004/002438
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English (en)
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Benoit Reid
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Bookham Technology Plc
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/20—Structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical axis, e.g. index or gain guiding, stripe geometry, broad area lasers, gain tailoring, transverse or lateral reflectors, special cladding structures, MQW barrier reflection layers
    • H01S5/22—Structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical axis, e.g. index or gain guiding, stripe geometry, broad area lasers, gain tailoring, transverse or lateral reflectors, special cladding structures, MQW barrier reflection layers having a ridge or stripe structure
    • H01S5/223—Buried stripe structure
    • H01S5/2231—Buried stripe structure with inner confining structure only between the active layer and the upper electrode
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/12—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/065—Mode locking; Mode suppression; Mode selection ; Self pulsating
    • H01S5/0651—Mode control
    • H01S5/0653—Mode suppression, e.g. specific multimode
    • H01S5/0654—Single longitudinal mode emission
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/12—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers
    • H01S5/1237—Lateral grating, i.e. grating only adjacent ridge or mesa

Definitions

  • the present invention pertains to the field of ridge waveguides. More specifically, the present invention relates to weakly guiding ridge waveguides with vertical gratings.
  • Waveguide structures are commonly used in lasers to restrict the three dimensional propagation of electromagnetic waves to a single dimension.
  • the edge- emitting laser is usually based on a waveguide structure, formed from different semiconductor materials to provide waveguiding in one direction.
  • the use of mirrors constructed from crystallographic "cleaves”, enables the required optical reflections.
  • a development of the basic laser constructed from a series of semiconductor layers, is the construction of a "ridge" in the top cladding layer of the slab guide.
  • An example of this design has been shown by Kamp et al, in "High Performance Laterally Gain Coupled InGaAs/AlGaAs DFB Lasers", IPRM 1998. Kamp et al.
  • lateral gratings can be successfully fabricated using electron-beam lithography.
  • the cross- section of such a laser is shown in Figure 1, wherein the laser design comprises lateral Cr grating, such that the evanescent field of the laser mode couples to the lateral Cr grating.
  • the ridge improves the lateral, namely horizontal, waveguiding of the optical mode.
  • Other ridge options have been developed allowing alternate methods of construction and providing improved concentration of the optical signal in the ridge area.
  • the semiconductor layers of the laser guide the light in the "vertical” direction and the ridge guides the light in the "horizontal” direction approximately between the ridge sidewalls.
  • the cleaved mirrors and gratings if present, provide feedback by reflections in the "longitudinal" direction.
  • Gratings may be formed directly adjacent to the active layer, or as part of the active layer itself. Additionally the gratings can be placed on either the horizontal or vertical surfaces of a ridge laser configuration. The vertical placement of these gratings can be called sidewall gratings.
  • DBR Distributed Bragg Reflector
  • DFB Distributed Feedback
  • a key part of the progress in the design of semiconductor lasers has been the development of the associated manufacturing methods. There has been a continuous effort to find ways to improve alternate techniques for building these lasers and methods of improving the accuracy of the final constructed laser.
  • the performance of a laser is highly dependent on the final physical accuracy of the layers, gratings and electrical contacts as well as the accuracy of the composition of the materials used.
  • the manufacturing process requires multiple steps of deposition and etching of layers of materials, and requires the materials to be relatively pure.
  • MOCVD metal organic chemical vapour deposition
  • MBE molecular beam epitaxy
  • advanced deposition techniques for dielectric and metal films has allowed significant steps for the improvement in production capability.
  • the standard method of fabricating lasers uses photolithography. In this process geometrical shapes on a mask are transferred to the semiconductor layers. This process is well known, proven and ideally suited to manufacturing. However due to diffraction, the photolithography process introduces a distortion of the required image, resulting in a blurring of the original image and a limitation in its resolution, typically achieving resolution levels in the range of 0.3 microns. Resolution defines the ability to discriminate between two points.
  • a resolution of 0.3 microns means that it is not possible to determine any feature smaller than 0.3 microns.
  • the guide wavelength in a semiconductor laser will be approximately 0.48 microns, giving a first order grating spacing of 0.24 microns, and as such gratings of this order may not be fabricated using photolithography.
  • the gratings may also be fabricated using a holographic method whereby two laser beams, which are split from a single laser, interfere with each other.
  • the interference pattern comprises fringes made of bright and dark lines.
  • a photoresist is illuminated with this pattern, which creates the grating.
  • the pitch of the grating which is usually first order, but could be of any order, is determined by the angle between the beams. Excellent accuracy can be achieved with this method and the holographic method is very suitable when the grating is identical over the whole surface of the wafer.
  • difficulties occur when the gratings are more complicated, and not uniform across the wafer, for example, patches of grating or variable gratings over the length of the wafer. For this scenario electron-beam lithography would typically be used.
  • Electron-beam lithography uses a scanning beam of electrons to define the desired pattern in the photoresist film. This technique is capable of very high resolution, which can be better than 0.03 microns. The process is a very flexible technique that can work with a variety of materials and patterns. However it is a slow process, being orders of magnitude slower than photolithography and requires more complicated and expensive manufacturing equipment.
  • FIG. 2 illustrates a schematic diagram of a DFB waveguide laser structure proposed by Miller et al. in "A Distributed Ridge Waveguide Quantum Well Heterostructure Laser", IEEE Photon. Tech. Lett., vol.3, 1991.
  • ⁇ Q is the period required to satisfy the Bragg condition
  • w is the laser stripe width
  • L G is the length of the etched region of the grating.
  • Miller et al. have demonstrated the ability to create third and fifth order DFB gratings using electron-beam lithography.
  • Lammert et al in "InGaAsP-InP ridge- waveguide DBR lasers with first order surface gratings fabricated using CAIBE", IEEE 1997, disclose an InGaAsP-inP Ridge- Waveguide DBR Laser with a First Order Grating as illustrated in Figure 3.
  • Lammert et al. show the feasibility of creating a ridge laser with first order gratings fabricated by a combination of electron-beam lithography and chemically assisted ion beam etching.
  • Watanabe et al in "Laterally Coupled Strained MQW Ridge Waveguide Distributed-Feedback Laser Diode Fabricated by Wet-Dry Hybrid Etching Process", IEEE Photon. Techn. Lett. Vol. 10, 1998, show a ridge waveguide with both lateral and vertical gratings. Watanabe et al. demonstrate the successful application of gratings with a ridge waveguide, using first order gratings fabricated with electron-beam lithography.
  • J. Wiedmann et al. disclose a DBR laser comprising a cavity with a vertical grating and a deeply etched DBR facet and demonstrate the possibility of deeply etching vertical gratings using electron-beam lithography.
  • first order gratings that is the grating spacing or pitch
  • first order gratings that is the grating spacing or pitch
  • second order grating would have twice the spacing
  • third order grating would have three times the spacing.
  • light can be scattered from the waveguide in a direction perpendicular to the grating, unlike with first order gratings. This effect has been used to couple light in and out of planar waveguides using surface, or horizontal gratings.
  • ridge waveguides used in semiconductor laser structures are typically strongly guiding waveguides.
  • the optical mode is almost entirely located in the ridge since the surrounding material is of a lower refractive index as illustrated in Figure 6.
  • WO 03102646 discloses the use of side gratings on both tightly and strongly guided waveguides using first order gratings, to form a DFB laser. These are illustrated in Figure 7 and 8, respectively.
  • US Patent No. 5,659,640 further discloses tightly guiding buried waveguides using first order gratings to produce a filter that may be optically connected to a laser, with the waveguide structure fabricated using a selective growth technique.
  • US Patent No. 5,930,437 discloses a strongly guiding buried geometry waveguide that is buried in a lower refractive index material.
  • Strongly guiding waveguides are typically used since these waveguides will have a good overlap with the gratings due to the presence of the optical mode in the ridge.
  • the light travels in air next to the ridge. Therefore, in applications where metal connections to the waveguide are required, for example, such connections can interfere with the light from strongly guiding waveguides. This can be a problem when integrating various optical circuits and devices.
  • An object of the present invention is to provide weakly guiding ridge waveguides with vertical gratings.
  • an integrated optical device comprising a weakly guiding ridge waveguide formed on a substrate, said weakly guiding ridge waveguide including a ridge with a vertical grating structure, said weakly guiding ridge waveguide guiding an optical mode substantially beneath the ridge.
  • a method of forming an optical waveguide comprising the steps of: depositing one or more layers of an optical waveguide material on a substrate material, a layer of said substrate material having a first index of refraction and a layer of said optical waveguide material having a second index of refraction, wherein said first index of refraction is higher than the second index of refraction; creating a mask on said optical waveguide material, said mask having a pattern, said pattern defining a ridge waveguide region with vertical gratings; and etching away a portion of the optical waveguide material determined by the mask, thereby forming a ridge waveguide with vertical gratings.
  • a method of forming an optical waveguide comprising the steps of: depositing one or more layers of an optical waveguide material on a substrate material, a layer of said substrate material having a first index of refraction and a layer of said optical waveguide material having a second index of refraction, wherein said first index of refraction is higher than the second index of refraction, said optical waveguide material being photon, electron, ion or neutral atom sensitive; exposing the optical waveguide material to a predetermined radiation or particle in a pattern defining a ridge waveguide region with vertical gratings, whereby the optical waveguide material exposed to the predetermined radiation is altered, thereby defining a ridge waveguide with vertical gratings.
  • a method of forming an optical waveguide comprising the step of selectively depositing one or more layers of an optical waveguide material defining a ridge waveguide region with vertical gratings, said optical waveguide material being selectively deposited on a substrate material, a layer of said substrate material having a first index of refraction and a layer of said optical waveguide material having a second index of refraction, wherein said first index of refraction is higher than the second index of refraction, said step of selectively depositing, thereby forming a ridge waveguide with vertical gratings.
  • an integrated optical device comprising: a substrate having one or more layers of material thereon, one of said layers having a first index of refraction; and a ridge waveguide formed on said substrate, said ridge waveguide including a vertical grating structure, said ridge waveguide having one or more layers, one of said layers having a second index of refraction; wherein said first index of refraction is higher than the second index of refraction thereby forming a weakly guiding waveguide.
  • Figure 1 is a schematic layout of a ridge waveguide laser, and shows the evanescent field of the laser mode coupling to the lateral Cr grating as shown by Kamp et al.
  • Figure 2 is a schematic diagram of a distributed feedback ridge waveguide laser, defining the grating period requirement needed to satisfy the Bragg condition as shown by Miller et al.
  • Figure 3 is a schematic diagram of an InGaAsP-InP ridge-waveguide DBR laser with a first order grating as shown by Lammert et al.
  • Figure 4 shows a laterally coupled strained MQW ridge waveguide distributed-feedback laser diode fabricated by wet-dry hybrid etching process as shown by Y. Watanabe et al.
  • Figure 5 shows a schematic of a DBR laser comprising a cavity with a vertical grating and a deeply etched DBR facet as shown by from J. Wiedmann et al.
  • Figure 6 shows a strongly guiding corrugated ridge waveguide.
  • Figure 7 shows a schematic of a tightly guiding ridge waveguide according to Hastings et al.
  • Figure 8 shows a schematic of a strongly guiding ridge waveguide according to Hastings et al.
  • Figure 9 shows a weakly guiding corrugated ridge waveguide.
  • Figure 10 shows one embodiment of the present invention wherein gratings on a semiconductor laser allow transfer of optical energy to another device.
  • Figure 11 shows a basic semiconductor laser structure before the formation of a ridge.
  • Figures 12A to 12D demonstrate the key . steps of the fabrication process for a laser employing one embodiment of the present invention.
  • Figure 13 A illustrates power-current characteristics of a Fabry-Perot laser and a corrugated-ridge DFB laser employing one embodiment of the present invention.
  • Figure 13B shows typical spectra of the corrugated-ridge laser of Figure 13 A measured at various drive currents.
  • Figure 13C shows the measured heterodyne signal for the structure of Figure 13 A.
  • Figure 14A illustrates one embodiment of the present invention wherein the grating pitch is different on either side of the ridge.
  • Figure 14B illustrates one embodiment of the present invention wherein gratings are designed in sets.
  • Figure 14C illustrates one embodiment of the present invention wherein sets of gratings have varying separation therebetween.
  • Figure 14D illustrates one embodiment of the present invention wherein the amplitude of the gratings is different at two ends of the ridge.
  • the term "light” is used to define radiation in any region of the electromagnetic spectrum.
  • optical is used to define a relation to visible light as well as radiation in any other regions of the electromagnetic spectrum.
  • photolithography is used to define a lithography process in which photons from any region of the electromagnetic spectrum may be used to produce a particular pattern on a radiation sensitive material.
  • a lithography process may comprise the use of G-line (436 nm), H-line (405 nm) and/or I-line (365 nm) wavelengths of radiation.
  • Other examples of photolithography processes include deep ultraviolet (UN) lithography and x-ray lithography.
  • photolithography is further used to define various techniques of lithography, for example, stepper lithography, mask lithography, holography techniques, and any other lithography techniques as would be readily understood by a worker skilled in the art.
  • the present invention provides a design and method of fabrication of a ridge waveguide structure with vertical gratings enabling weak guiding of light.
  • weakly guiding waveguide structures only a small portion of light from an optical mode is guided by the waveguide, with majority of the optical mode being present in a material outside of the waveguide structure.
  • an optical mode 93 is generated by a device such as a laser or other optical device as would be readily understood by a worker skilled in the art, in a substrate 92 and a waveguide structure with vertical gratings 91 is in contact with the material in which the optical mode is present, as illustrated in Figure 9.
  • the waveguide structure with vertical gratings uses materials of appropriate refractive index to provide weak guiding of light.
  • the optical mode may be confined within a high refractive index layer.
  • the optical mode may be centered within the high refractive index material.
  • the weakly guiding waveguide is designed such that the size and dimensions of the ridge waveguide limit the optical mode from substantially entering the ridge waveguide, thereby resulting in weak guiding of light by the waveguide structure.
  • Other methods as would be readily understood by a worker skilled in the art, may also be used in designing weakly guiding waveguide structures.
  • the optical mode of the device may not be generated directly below the waveguide structure of the present invention but may be guided to other material that is in contact with the waveguide structure.
  • weakly guiding waveguide structures An advantage of weakly guiding waveguide structures is that essentially no light travels in the air next to the ridge waveguide. Therefore, metal connections can be made to the weakly guiding waveguide structure, which enables integration of various optical circuits that may comprise weakly guiding waveguide structures.
  • Embodiments of the present invention further enable the use of a photolithographic process, such as stepper lithography, for definition of the vertical grating geometries, which is a less complex and cheaper lithography process when compared to the electron-beam lithography process, which is typically used for current designs of vertical gratings.
  • a photolithographic process such as stepper lithography
  • the present invention also allows for a variety of vertical grating structures to be defined and fabricated in the ridge for weakly guiding waveguide structures.
  • the waveguide structure according to the present invention further enables lateral coupling of light from the waveguide structure to other optical structures that may be placed in a lateral plane that is parallel to the surface of the waveguide structure. This can be useful when multiple optical circuits or devices are integrated onto a single chip, for example.
  • the lateral light output from a ridge waveguide structure with vertical gratings is incident upon a detector, which can detect the intensity as well as wavelength of the light.
  • the present invention may be used to achieve spatial modulation of the loss of light along the waveguide, which results from a variation in the position of the optical mode along the length of the waveguide structure.
  • the design and fabrication of the waveguide structure according to the present invention may simplify the overall fabrication process of structures that incorporate the waveguides. For example, the number of fabrication steps may be reduced for certain devices incorporating the waveguide structure of the present invention.
  • the waveguide structure of the present invention may be used in various devices such as semiconductor lasers, filters, tunable filters, and other devices as would be readily understood by a worker skilled in the art.
  • appropriate embodiments of the present invention may be used with Distributed Feedback (DFB) lasers or Distributed Bragg Reflector (DBR) lasers.
  • DFB Distributed Feedback
  • DBR Distributed Bragg Reflector
  • Both types of laser designs rely on the use of periodic grating structures for providing high reflectivity of light resulting from spacing the gratings an integer number of half wavelengths apart, for example ⁇ /2, 3 ⁇ /2, 5 ⁇ /2, and so on, thus enabling the reflections to be in phase with each other.
  • One embodiment of the present invention can additionally be used to produce vertical gratings containing phase shifts, for example a quarter wavelength phase shift, wherein this alteration can cause the structure to act as a resonator that stores energy.
  • one embodiment of the present invention may be used in tunable semiconductor lasers, for example, DBR lasers that rely on tuning of the injected current.
  • Embodiments of the present invention may also be used with various optical integrated circuits.
  • the grating associated with the ridge may be passive or active, and will be active if a contact is placed thereon.
  • an electrode is formed on the top surface of the waveguide structure.
  • the waveguide may be used as a tunable filter, for example, wherein the wavelength of light passing through a waveguide may depend on the voltage or cunent applied to an electrode on the waveguide.
  • the scattering of light may further be dependent upon the applied current or voltage.
  • the vertical grating symmetry, pitch and/or depth are variable thus providing various filtering effects and a plurality of design potentials for filters designed according to embodiments of the present invention.
  • first order gratings are typically used in ridge waveguides with vertical gratings, as essentially no light is scattered perpendicular to the grating plane with this grating configuration.
  • the vertical grating patterning process can be faster, less complex and more economical by enabling the use of photolithography in place of the typically used electron-beam lithography for grating fabrication.
  • the light scattered from the vertical grating of higher order grating designs according to the present invention can be advantageously used to couple light laterally from the waveguide structure to other optical circuits and structures within a particular proximity.
  • This present invention may use higher order vertical gratings, which have larger spacing dimensions when compared to first order gratings, thus potentially enabling the manufacture of these gratings using a photolithographic process.
  • the waveguide wavelength in a semiconductor laser is approximately 0.48 microns, giving a first order spacing of 0.24 microns, a second order spacing of 0.48 microns, a third order spacing of 0.72 microns, and so on.
  • the most commonly available photolithography systems have a resolution in the order of approximately 0.3 microns. Therefore using a third order grating with a pitch of 0.72 microns, the smallest feature namely the gap or tooth of the grating would be approximately 0.36 microns, assuming that the grating has a 50/50 mark-to-space ratio.
  • Such a grating size can thus be fabricated using a photolithographic process, however as the smallest feature size is close to the resolution limit of the photolithographic method, the vertical grating may have some level of erosion.
  • Photolithography is a widely used lithographic process in semiconductor fabrication and is more economical, partially as a result of well established systems and techniques, compared to other types of lithography such as electron-beam lithography. It is also a less complex method of patterning compared to electron-beam lithography, which as described earlier is the typical method used in vertical first order grating waveguide fabrication.
  • holographic patterning techniques are commonly used to pattern gratings.
  • An advantage of using a mask or stepper photolithography technique as opposed to a holographic technique for the fabrication of the vertical gratings is that the design can encompass variations of grating structure and is not limited to an interference pattern. For example different orders of vertical gratings may be combined on a particular ridge thereby extending the design capability for a device having this type of waveguide structure. Therefore a very broad range of options in vertical grating combinations and designs are available using a mask or stepper photolithography fabrication technique for ridge waveguides having vertical ridge gratings.
  • the photolithographic process for manufacturing such waveguides can be highly repeatable and can meet the needs of an efficient manufacturing process.
  • photolithography does not have the complexity of programming a complicated track for etching, as is needed for electron-beam lithography.
  • the vertical gratings allow coupling of light to occur between the waveguide structure and other devices. These devices may be other waveguides, photodetectors or other optical systems. Because the gratings in the present invention are vertical, the coupling of the light occurs laterally, that is, in a plane that is parallel to the top surface of the ridge waveguide of the present invention. It is well known that a grating can couple light in and out of a waveguide, however most gratings are horizontal therefore this coupling occurs in the plane perpendicular to the surface of the wafer. According to the present invention, the coupling occurs horizontally, thereby allowing the possibility of integrating many devices onto the same chip, with the transfer of light therebetween.
  • coupling of light can occur laterally from the optical mode below the ridge material.
  • the optical mode is primarily present below the ridge waveguide as illustrated in Figure 9.
  • Light 94 from the optical mode can therefore also be coupled out laterally within the substrate material 92.
  • the optical mode is primarily located in the ridge waveguide, since the optical mode is primarily located in the ridge waveguide, light 64 is primarily coupled laterally from the waveguide 61 rather than within the substrate 63.
  • An advantage of having light scattered in a direction perpendicular to the grating as in the case of higher order gratings is that the light can be coupled to other optical circuits and structures that are in a lateral plane parallel to the plane of the waveguide structure.
  • it is possible to couple light from a vertical first order grating by using blazing techniques which entail controlling the cross-sectional shape of the vertical grooves or teeth to concentrate the light in a desired region.
  • an antireflective (AR) coating may be applied to the emitting surface of the vertical grating and in other embodiments this may not be necessary.
  • Figure 10 shows the top view of a weakly guiding ridge waveguide with vertical gratings 101 according to one embodiment of the present invention, whereby the optical signal 102 is transmitted from the waveguide to another adjacent device 103.
  • the ability of the present invention to couple light laterally in a plane parallel to the top surface of the waveguide structure can be an important advantage. For example, there are certain applications that require data to be transmitted on the light using a directly- modulated laser or using a laser with an external modulator, for example a Mach- Zehnder modulator.
  • the laser and the modulator are typically fabricated on two separate chips and need to be aligned in the package with other optics and electronics. For manufacturing ease and cost reduction, there is a tendency to integrate more functions on a single chip. It is therefore advantageous to laterally couple the light between such devices wherein this coupling is enabled by the use of a weakly guiding ridge waveguide with vertical gratings according to the present invention.
  • the light from the waveguide structure of the present invention may be laterally coupled to a detector.
  • the detector may be used to monitor the power of the light or the wavelength of the light, for example.
  • the detector may be a reverse-biased p-n junction such that any light entering the detector produces a proportional current that can be measured, thereby providing a measure of the power of the light coupled from the waveguide.
  • some or all the light coupled from the waveguide can be detected. Therefore, the power of the light propagating within the waveguide may also be determined.
  • the detected light can provide an indication of the wavelength of the light coupled from the waveguide structure.
  • This wavelength monitoring can be possible since light that couples out of a vertical grating, typically a blazed or higher order grating, does so parallel to the plane of the substrate, such that the angle the propagating light makes with the direction of the waveguide is a function of the wavelength of the light and of the pitch of the grating. Therefore, the light that contacts a detector or one of an array of detectors is a function of the wavelength. Therefore, the angle at which the light is detected is indicative of its wavelength.
  • An array of detectors may thus be used to detect various wavelengths of light that may be coupled out of the waveguide structure.
  • the light coupled out of the waveguide structure may be small such that the detector or detectors act as an in-line wavelength monitor, thereby enabling most of the light to continue to propagate along the waveguide with only a small amount of the light used to determine the wavelength thereof. As would be readily understood, any desired amount of light may be used for such detection.
  • the light coupled from the waveguide may be incident upon another waveguide structure designed to couple the light therein.
  • the weakly guiding ridge waveguide with vertical gratings according to the present invention may further be used to introduce spatially modulated variations in the loss of light along the waveguide structure, that is, modulated loss coupling can be introduced in the waveguide structure.
  • This may be an approximately periodic variation in the optical loss from the waveguide as the light propagates along the waveguide structure.
  • the optical mode comes closer to the surface where the ridge is narrower as compared to where the ridge width is wider.
  • a lossy material for example a metal
  • placing a lossy material, for example a metal, on the surface of the teeth of the vertical grating can result in a greater loss of light from the narrower regions of the waveguide compared to the wider regions, which can result in the optical loss associated with the device varying or being modulated, along the length of the waveguide structure.
  • Spatial modulation of loss may also be introduced along the waveguide structure by placing materials with other properties that affect the loss characteristics of light from the waveguide.
  • the material may have a non-linear effect on the loss or may suppress loss.
  • the material may be placed only on particular regions of the grating surface in order to introduce desired loss characteristics to desired regions of the waveguide.
  • the active region is remote from the ridge, and as a result, the cunent is not modulated, subsequently resulting in no gain coupling.
  • this modulated loss coupling technique described above there may be the ability to introduce loss coupling.
  • in higher order gratings there will be some scattered light that is modulated along the cavity to give loss modulation.
  • the coupling can be small since the optical mode is below the surface and because higher order gratings are used.
  • a typical design goal is for kL ⁇ 1, where k is the coupling coefficient and L is the length of the laser. A higher value of kL is required for a directly modulated laser. If k is small, then L needs to be longer.
  • a usual DFB laser would be around 200-400 microns in length.
  • a DFB laser using the weakly guided waveguide structure with vertical gratings according to one embodiment of the present invention would be between 1000-2000 microns in length, which has the advantage of providing improved power dissipation and hence higher optical power capability.
  • a weakly guiding ridge waveguide with vertical gratings of second order or higher is used in a semiconductor laser structure.
  • the design is not limited by substrate material, for example InP, or GaAs or GaN or whether the substrate is a p-substrate or n-substrate.
  • a worker skilled in the art would readily understand the types of layers, materials and thicknesses, that would be necessary in order to manufacture a ridge semiconductor laser with a weakly guiding waveguide structure with vertical gratings according to the present invention, wherein these materials would be designed to be compatible with the substrate being used.
  • a vertically-coupled DFB ridge type semiconductor laser of GaAsP/InP type is manufactured by means of metal organic chemical vapor deposition (MOCND) using an organometallic compound gas, together with standard deposition techniques.
  • MOCND metal organic chemical vapor deposition
  • a wafer of an n-InP crystalline substrate 60 is prepared having a predetermined plane orientation. Chemical etching is performed to clean the surface of the wafer. Then a layer 50 of InGaAsP is formed on the cleaned surface of the wafer 60 in order to fabricate an active layer region for the semiconductor structure.
  • the process used for forming this layer can involve methods such as epitaxial growth, liquid phase epitaxial growth, metal organic chemical vapor deposition, molecular beam epitaxial growth for example, or alternate techniques as would be readily understood by a worker skilled in the art of semiconductor manufacture.
  • the active layer 50 could be a bulk layer, or a single quantum well layer, or multiple quantum well layers that are mainly composed of InGaAsP.
  • a cladding layer 40 made of a material such as p- InP is deposited on the active layer 50.
  • An etch termination 30 layer is then deposited on the cladding layer 40.
  • a second cladding layer 20 made of a material for a ridge stripe such as p-InP is then deposited on the etch termination layer 30.
  • a contact layer 10 is deposited on top of the cladding layer 20.
  • the composition of an appropriate contact layer for this material system would be readily understood by a worker skilled in the art.
  • Figure 12A illustrates the completion of the structure as defined above in relation to Figure 11 with a dielectric layer 5 deposited on top.
  • Contact layer 10 is not shown for simplicity, however is present on top of the ridge material 20.
  • a photoresist layer (not shown) is deposited on this structure and a photolithography process is used to transfer the desired grating pattern to the photoresist, thus defining the pattern for the vertical gratings.
  • a stepper lithography process for example, may be used in the photolithography process.
  • the pattern is then transferred from the patterned photoresist layer to the dielectric layer 5 by etching thus forming a hard mask 51, followed by removal of the photoresist layer.
  • the resulting structure is illustrated in Figure 12B.
  • the etching process for the gratings can use a combination of processes including plasma and liquid base chemical reactions to transfer the pattern defined in the hard mask 51 into the contact layer 10 (not shown in Figure 12) and ridge material 20 thus forming structure 201 as illustrated in Figure 12C.
  • the hard mask 51 is then removed as illustrated in Figure 12D and the basic ridge waveguide 201 having the desired order vertical gratings is ready for the remaining standard steps of fabrication.
  • the optical mode 1 is positioned substantially beneath the ridge thereby resulting in a weakly guiding waveguide.
  • a dielectric (not shown), for example, silicon dioxide or silicon nitride, may then be deposited over the entire region embedding the ridge and the gratings.
  • a via can be formed in the dielectric layer on the top of the ridge thus exposing the contact layer 10.
  • ohmic contacts can be fabricated on the top side and the back side of the laser.
  • Embodiments of the present invention may similarly be implemented in various other laser structures.
  • the laser may comprise a substrate of a first conductivity type, for example n- InP; a cladding layer of the same conductivity type, for example n-InP, wherein this cladding layer can include a plurality of layers of the same material with different doping levels; an active region, which can be doped with either conductivity type, or undoped and can be fabricated from alloys, for example alloys of InGaAsP, wherein the active region can include a plurality of layers and/or single or multiple quantum wells; a cladding layer of the opposite conductivity type, for example p-InP, wherein this cladding layer can comprise a plurality of layers of the same material with different doping levels and the cladding layer can comprise an etch-stop layer for the fabrication; a third-order grating (or any other order) substantially etched vertically on the sidewalls in the p-cladding layer forming the ridge.
  • a first conductivity type for example n- InP
  • the structure can have a contact layer and additionally electrodes on both sides.
  • a contact layer and additionally electrodes on both sides.
  • the terms "on” and “on top of refer to the sequence of construction, and would allow the normal additional minor processes necessary for such construction.
  • the material may be selectively deposited or grown to form the waveguide structure.
  • a material that is sensitive to photons, electrons, ions or neutral atoms is deposited and patterned using lithographic techniques, wherein the material properties change upon exposure. These changes may include variations in refractive index or solubility of the material in certain chemicals, for example. Subsequent to exposure, either the altered or unaltered material may be etched away thereby forming the ridge waveguide with vertical gratings.
  • a typical DFB ridge waveguide laser requires a two-growth sequence, with a grating fabrication step in between for the construction of the vertical gratings.
  • the creation of the vertical grating during the ridge step allows the laser to be fabricated with two fewer steps in its overall construction, for example. This reduction in the number of steps in the manufacturing process can provide a significant reduction in the overall cost to manufacture the laser and can provide a greater yield in the overall production of these lasers.
  • each of these chips are typically fabricated using different processes.
  • the number of fabrication steps can increase to produce a single chip, with a possible consequent decrease in the yield and increase in cost of this chip.
  • embodiments of the invention may decrease the number of steps to fabricate the laser, there can be a corresponding decrease in the overall number of steps to fabricate the combined laser and Mach-Zehnder modulator on a single chip. This is one example of many system designs where embodiments of the invention can simplify and improve the overall performance, allowing increased yield and reduced cost.
  • FIG 13 A to Figure 13C illustrate the performance of a DFB laser structure employing one embodiment of the present invention.
  • This device was fabricated using stepper lithography for the definition of the vertical grating waveguide structure.
  • Figure 13 A shows the power output for the above laser and a Fabry-Perot laser structure as a function of injection current.
  • Curve 131 illustrates the power output for the Fabry- Perot laser and curve 132 illustrates the curve for the DFB laser structure fabricated with an embodiment of the present invention.
  • Figure 13B illustrates typical spectra of the DFB laser at various drive currents.
  • Curve 133 represents a 100 mA drive current
  • curve 134 represents a 300 mA drive current
  • curve 135 represents a 700 mA drive current. The curves have been displaced vertically and horizontally for clarity.
  • a high SMSR side-mode suppression ratio
  • Figure 13C illustrates the measured heterodyne signal 137 used to extract the optical linewidth, and demonstrates the nanow bandwidth for the DFB laser which is less than 1 MHz at - 3 dB from the peak.
  • the present invention further allows the fabrication of weakly guiding ridge waveguides with vertical gratings having a wide range of grating depths, widths and spacing, thus enabling many designs to be produced, for example chirp grating designs.
  • Figure 14A to Figure 14D illustrate vertical grating designs according to various embodiments of the present invention. These embodiments are provided as examples and do not limit the types of designs achievable.
  • Figure 14A illustrates an embodiment in which the vertical grating structures are different on either side of the ridge 141. It can be seen that vertical gratings 142 have a different pitch compared to gratings 143.
  • Figure 14B illustrates vertical gratings in sets 145, or sampled gratings, along the ridge 144, where each set 145 is separated by a particular distance 146.
  • Figure 14C illustrates chirped sampled vertical gratings 148, where the spacing 149 between the sets varies.
  • Figure 14D illustrates an embodiment in which the amplitude of the vertical gratings varies at two ends of the ridge 150. Gratings 151 have a smaller amplitude compared to gratings 152.
  • the embodiment illustrated in Figure 14D may be used in an anti-reflective/high-reflective (AR/HR) DBR laser, for example.
  • the gratings may have other variations in pitch and/or amplitude.
  • the gratings may be angled/blazed gratings.

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  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optics & Photonics (AREA)
  • Geometry (AREA)
  • Optical Integrated Circuits (AREA)
  • Semiconductor Lasers (AREA)

Abstract

La présente invention concerne une configuration et un mode de fabrication d’une structure de guide d’ondes nervuré à sélecteurs de mode verticaux permettant un guidage faible de la lumière. Dans des structures de guide d’ondes à guidage faible, seule une faible partie de la lumière provenant d’un mode optique est guidée par le guide d’ondes, la majorité de la lumière du mode optique étant présente dans un matériau à l’extérieur de la structure de guide d’ondes. La présente invention concerne également un dispositif optique intégré comportant un guide d’ondes nervuré à guidage faible formé sur un substrat et comprenant une nervure pourvue d’une structure de sélecteurs de mode verticaux, ledit guide d’ondes guidant un mode optique sensiblement sous la nervure. Ladite structure de guide d’ondes à sélecteurs de mode verticaux met en œuvre des matériaux d’un indice de réfraction approprié pour assurer un guidage faible de la lumière. Ladite structure de guide d’ondes permet d’autre part le couplage latéral de la lumière émanant d’elle-même avec d’autres structures optiques pouvant être placées dans un plan latéral qui est parallèle à la surface de la structure de guide d’ondes.
PCT/IB2004/002438 2003-07-31 2004-07-30 Guide d’ondes nervuré à sélecteurs de mode verticaux à guidage faible WO2005011076A1 (fr)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006045632A1 (fr) * 2004-10-26 2006-05-04 Forschungsverbund Berlin E.V. Element optique et son procede de production
EP1742314A2 (fr) 2005-06-16 2007-01-10 Avago Technologies Fiber IP (Singapore) Pte. Ltd. Dispositif à jonction hétéro enterré avec guide d'ondes à reseau fabriqué avec de la MOCVD à une seule etape
JP2011070177A (ja) * 2009-08-28 2011-04-07 Fujikura Ltd グレーティング構造を有する基板型光導波路デバイス
US8934512B2 (en) 2011-12-08 2015-01-13 Binoptics Corporation Edge-emitting etched-facet lasers
WO2016076793A1 (fr) * 2014-11-10 2016-05-19 Agency for Science,Technology and Research Dispositif optique et son procédé de fabrication
WO2017220144A1 (fr) * 2016-06-22 2017-12-28 Tty-Säätiö Sr Structure laser à semi-conducteur comportant un réseau de diffraction et de multiples déphasages
WO2018019955A1 (fr) * 2016-07-27 2018-02-01 Universite Paris Sud Diode laser à rétroaction répartie
CN113544920A (zh) * 2019-03-06 2021-10-22 思科技术公司 超模式滤波波导发射器
CN114825045A (zh) * 2022-06-24 2022-07-29 度亘激光技术（苏州）有限公司 抗反射激光器及其制备方法
DE112013007730B4 (de) 2013-12-27 2023-12-28 Intel Corporation Asymmetrische optische Wellenleitergitterresonatoren und DBR-Laser

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS55115002A (en) * 1979-02-28 1980-09-04 Toshiba Corp Waveguide type photo branching filter
JPS62145208A (ja) * 1985-12-19 1987-06-29 Matsushita Electric Ind Co Ltd 導波路回折格子の製造方法
US5278926A (en) * 1991-12-04 1994-01-11 Alcatel Alsthom Compagnie Generale Widened output mode semiconductor optical component and method of fabricating it
US5574743A (en) * 1994-03-22 1996-11-12 U.S. Philips Corporation Semiconductor diode laser having improved performance and method of manufacturing same
US5930437A (en) * 1996-05-24 1999-07-27 Fujikura Ltd. Optical filter with planar optical waveguide having periodically varied distribution of refractive index and production process thereof
US6519272B1 (en) * 1999-06-30 2003-02-11 Corning Incorporated Long, high-power semiconductor laser with shifted-wave and passivated output facet
WO2003102646A2 (fr) * 2002-05-30 2003-12-11 Massachusetts Institute Of Technology Guide d'ondes optiques a reseau non-uniforme sur les parois laterales

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS55115002A (en) * 1979-02-28 1980-09-04 Toshiba Corp Waveguide type photo branching filter
JPS62145208A (ja) * 1985-12-19 1987-06-29 Matsushita Electric Ind Co Ltd 導波路回折格子の製造方法
US5278926A (en) * 1991-12-04 1994-01-11 Alcatel Alsthom Compagnie Generale Widened output mode semiconductor optical component and method of fabricating it
US5574743A (en) * 1994-03-22 1996-11-12 U.S. Philips Corporation Semiconductor diode laser having improved performance and method of manufacturing same
US5930437A (en) * 1996-05-24 1999-07-27 Fujikura Ltd. Optical filter with planar optical waveguide having periodically varied distribution of refractive index and production process thereof
US6519272B1 (en) * 1999-06-30 2003-02-11 Corning Incorporated Long, high-power semiconductor laser with shifted-wave and passivated output facet
WO2003102646A2 (fr) * 2002-05-30 2003-12-11 Massachusetts Institute Of Technology Guide d'ondes optiques a reseau non-uniforme sur les parois laterales

Non-Patent Citations (10)

* Cited by examiner, † Cited by third party
Title
KAMP M ET AL: "High performance laterally gain coupled InGaAs/AlGaAs DFB lasers", INDIUM PHOSPHIDE AND RELATED MATERIALS, 1998 INTERNATIONAL CONFERENCE ON TSUKUBA, JAPAN 11-15 MAY 1998, NEW YORK, NY, USA,IEEE, US, 11 May 1998 (1998-05-11), pages 831 - 834, XP010295347, ISBN: 0-7803-4220-8 *
LAMMERT R M ET AL: "InGaAsP-InP ridge-waveguide DBR lasers with first-order surface gratings fabricated using CAIBE", LASERS AND ELECTRO-OPTICS SOCIETY ANNUAL MEETING, 1997. LEOS '97 10TH ANNUAL MEETING. CONFERENCE PROCEEDINGS., IEEE SAN FRANCISCO, CA, USA 10-13 NOV. 1997, NEW YORK, NY, USA,IEEE, US, 10 November 1997 (1997-11-10), pages 278 - 279, XP010252557, ISBN: 0-7803-3895-2 *
LAMMERT R M ET AL: "LOW-THRESHOLD NARROW-LINEWIDTH INGAAS-GAAS RIDGE-WAVEGUIDE DBR LASERS WITH FIRST-ORDER SURFACE GRATINGS", 1 February 1997, IEEE PHOTONICS TECHNOLOGY LETTERS, IEEE INC. NEW YORK, US, PAGE(S) 149-151, ISSN: 1041-1135, XP000683851 *
MILLER L M ET AL: "A DISTRIBUTED FEEDBACK RIDGE WAVEGUIDE QUANTUM WELL HETEROSTRUCTURE LASER", IEEE PHOTONICS TECHNOLOGY LETTERS, IEEE INC. NEW YORK, US, vol. 3, no. 1, 1991, pages 6 - 8, XP000202985, ISSN: 1041-1135 *
PATENT ABSTRACTS OF JAPAN vol. 0041, no. 68 (P - 037) 20 November 1980 (1980-11-20) *
PATENT ABSTRACTS OF JAPAN vol. 0113, no. 75 (P - 644) 8 December 1987 (1987-12-08) *
RIGOLE P-J ET AL: "114-NM WAVELENGTH TUNING RANGE OF A VERTICAL GRATING ASSISTED CODIRECTIONAL COUPLER LASER WITH A SUPER STRUCTURE GRATING DISTRIBUTED BRAGG REFLECTOR", IEEE PHOTONICS TECHNOLOGY LETTERS, IEEE INC. NEW YORK, US, vol. 7, no. 7, 1 July 1995 (1995-07-01), pages 697 - 699, XP000516827, ISSN: 1041-1135 *
WIEDMANN J ET AL: "GAINASP/INP DISTRIBUTED REFLECTOR LASERS CONSISTING OF DEEPLY ETCHED VERTICAL GRATINGS", JAPANESE JOURNAL OF APPLIED PHYSICS, PUBLICATION OFFICE JAPANESE JOURNAL OF APPLIED PHYSICS. TOKYO, JP, vol. 40, no. 12, PART 1, December 2001 (2001-12-01), pages 6845 - 6851, XP001093223, ISSN: 0021-4922 *
WONG V V ET AL: "RIDGE-WAVEGUIDE SIDEWALL-GRATING DISTRIBUTED FEEDBACK STRUCTURES FABRICATED BU X-RAU LITHOGRAPHY", JOURNAL OF VACUUM SCIENCE AND TECHNOLOGY: PART B, AMERICAN INSTITUTE OF PHYSICS. NEW YORK, US, vol. 11, no. 6, 1 November 1993 (1993-11-01), pages 2621 - 2624, XP000423417, ISSN: 1071-1023 *
YOSHIAKI WATANABE ET AL: "LATERALLY COUPLED STRAINED MQW RIDGE WAVEGUIDE DISTRIBUTED-FEEDBACKLASER DIODE FABRICATED BY WET-DRY HYBRID ETCHING PROCESS", IEEE PHOTONICS TECHNOLOGY LETTERS, IEEE INC. NEW YORK, US, vol. 10, no. 12, December 1998 (1998-12-01), pages 1688 - 1690, XP000802155, ISSN: 1041-1135 *

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* Cited by examiner, † Cited by third party
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US7941024B2 (en) 2004-02-25 2011-05-10 Avago Technologies Fiber Ip (Singapore) Pte. Ltd Buried heterostructure device having integrated waveguide grating fabricated by single step MOCVD
WO2006045632A1 (fr) * 2004-10-26 2006-05-04 Forschungsverbund Berlin E.V. Element optique et son procede de production
EP1742314A2 (fr) 2005-06-16 2007-01-10 Avago Technologies Fiber IP (Singapore) Pte. Ltd. Dispositif à jonction hétéro enterré avec guide d'ondes à reseau fabriqué avec de la MOCVD à une seule etape
EP1742314A3 (fr) * 2005-06-16 2008-11-12 Avago Technologies Fiber IP (Singapore) Pte. Ltd. Dispositif à jonction hétéro enterré avec guide d'ondes à réseau fabriqué avec de la MOCVD à une seule étape
JP2011070177A (ja) * 2009-08-28 2011-04-07 Fujikura Ltd グレーティング構造を有する基板型光導波路デバイス
US9893488B2 (en) 2011-12-08 2018-02-13 Macom Technology Solutions Holdings, Inc. Edge-emitting etched-facet lasers
US10044168B2 (en) 2011-12-08 2018-08-07 Macon Technology Solutions Holdings, Inc. Edge-emitting etched-facet lasers
US8934512B2 (en) 2011-12-08 2015-01-13 Binoptics Corporation Edge-emitting etched-facet lasers
US10038298B2 (en) 2011-12-08 2018-07-31 Macom Technology Solutions Holdings, Inc. Edge-emitting etched-facet lasers
DE112013007730B4 (de) 2013-12-27 2023-12-28 Intel Corporation Asymmetrische optische Wellenleitergitterresonatoren und DBR-Laser
WO2016076793A1 (fr) * 2014-11-10 2016-05-19 Agency for Science,Technology and Research Dispositif optique et son procédé de fabrication
WO2017220144A1 (fr) * 2016-06-22 2017-12-28 Tty-Säätiö Sr Structure laser à semi-conducteur comportant un réseau de diffraction et de multiples déphasages
JP2019522379A (ja) * 2016-07-27 2019-08-08 ウニヴェルシテ・パリ−シュド 分布帰還型レーザーダイオード
CN109643881A (zh) * 2016-07-27 2019-04-16 巴黎第十大学 分布式反馈激光二极管
FR3054734A1 (fr) * 2016-07-27 2018-02-02 Universite Paris Sud Diode laser a retroaction repartie
US10658816B2 (en) 2016-07-27 2020-05-19 Universite Paris Sud Distributed feedback laser diode
CN109643881B (zh) * 2016-07-27 2021-04-23 巴黎第十大学 分布式反馈激光二极管
JP7112387B2 (ja) 2016-07-27 2022-08-03 ウニヴェルシテ・パリ－シュド 分布帰還型レーザーダイオード
WO2018019955A1 (fr) * 2016-07-27 2018-02-01 Universite Paris Sud Diode laser à rétroaction répartie
CN113544920A (zh) * 2019-03-06 2021-10-22 思科技术公司 超模式滤波波导发射器
US11888290B2 (en) 2019-03-06 2024-01-30 Cisco Technology, Inc. Supermode filtering waveguide emitters
CN113544920B (zh) * 2019-03-06 2024-03-26 思科技术公司 超模式滤波波导发射器
CN114825045A (zh) * 2022-06-24 2022-07-29 度亘激光技术（苏州）有限公司 抗反射激光器及其制备方法

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