CN103811997A - Annular-electrode microcavity laser device - Google Patents
Annular-electrode microcavity laser device Download PDFInfo
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- CN103811997A CN103811997A CN201410072139.7A CN201410072139A CN103811997A CN 103811997 A CN103811997 A CN 103811997A CN 201410072139 A CN201410072139 A CN 201410072139A CN 103811997 A CN103811997 A CN 103811997A
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Abstract
The invention provides an annular-electrode microcavity laser device. The annular-electrode microcavity laser device comprises a substrate, a microcavity laser device formed on the substrate, a first conductive type of patterned electrode made from metal and in an annular shape, and formed at the outer side edge of the top of the microcavity laser device, and a second conductive type of electrode formed on the side surface of the microcavity laser device when the substrate is an insulated substrate, and formed on the back surface of the substrate or the side surface of the microcavity laser device when the substrate is a conductive substrate, wherein the first conductive type and the second conductive type are one of p-type and n-type respectively. According to the annular-electrode microcavity laser device provided by the invention, laser emission mode optical field distribution and carrier distribution are largely superposed in space to acquire a high gain, and then to realize single-mode laser emission.
Description
Technical field
The present invention relates to field of semiconductor lasers, relate in particular to a kind of annular electrode micro-cavity laser.
Background technology
Along with progress and the innovation of modern information technologies, opto-electronic device is gradually towards High Density Integration, high efficiency, low-power consumption and microminiaturized future development.
On sheet, in optical interconnection, the scheme that the signal of telecommunication of loading is converted into light signal mainly contains two kinds of methods: a kind of is by the light of laser output is passed through to optical modulator to realize the conversion of signal; Another kind is by the signal of telecommunication being directly loaded on laser, realizing by the output optical signal of the direct modulated laser of electric current.At present, sheet glazing interconnection technique is just towards the future development of low cost, two-forty, low-power consumption.
Than indirect modulation micro-cavity laser, directly the micro-cavity laser of modulation have volume little, simple in structure, be easy to the advantages such as integrated, thereby get the attention, become the focus of research instantly.Circular micro-cavity laser is the new laser of a kind of small size, low threshold value, low-power consumption.Its resonant cavity shape is different from common Fabry-Perot cavity shape, is disc-shape.Operation principle is mainly to realize the restriction to light field pattern by light in the continuous reflection of microcavity boundary, thereby in chamber, has produced the high Echo Wall (Wispering-Gallery, the WG) pattern of quality factor.
Fig. 1 is the stereogram of prior art disc electrode micro-cavity laser.Please refer to Fig. 1, this micro-cavity laser comprises InP substrate; Be formed at the micro-cavity laser on substrate; Be formed at the disc p electrode on micro-cavity laser, and n electrode is formed at the back side of InP substrate.
But, realizing in process of the present invention, applicant finds that prior art disc electrode micro-cavity laser is because electrode design is disc, in micro-dish-type laser active area, charge carrier is mainly distributed in laser center, and laser interior lights field mode is mainly distributed in the edge of disc microcavity, overlapping little between charge carrier and light field, the charge carrier injecting has considerable influence in the distribution situation of active area to the light restriction factor in micro-cavity laser pattern horizontal direction, affect the single mode operation performance of micro-cavity laser, simultaneously, inject under direct modulation case at electric current, charge carrier therefrom mind-set both sides diffusion phenomena is serious, affect the modulating speed of laser.
Summary of the invention
(1) technical problem that will solve
In view of above-mentioned technical problem, the invention provides a kind of annular electrode micro-cavity laser, to realize electrode position and mating that active area charge carrier distributes, obtain higher gain.
(2) technical scheme
Annular electrode micro-cavity laser of the present invention comprises: substrate 100; Micro-cavity laser 200, is formed on substrate 100; The patterned electrodes 300 of the first conduction type, its material is metal, its shape ringwise, is formed at the outer ledge at micro-cavity laser 200 tops; The electrode of the second conduction type, in the time that substrate 100 is dielectric substrate, is formed at the side of micro-cavity laser 200; In the time that substrate 100 is conductive substrates, be formed at the side of substrate 100 back sides or micro-cavity laser 200; Wherein, the first conduction type and the second conduction type are respectively one of them in p-type and N-shaped.
(3) beneficial effect
Annular electrode micro-cavity laser of the present invention, realize the control in distribution radially to active area charge carrier, thereby control the light restriction factor of the horizontal direction of different mode, excitation mode optical field distribution and charge carrier are distributed spatially have larger overlapping, obtain higher gain and then realize single module lasing.Can reduce the impact of carrier diffusion effect on micro-cavity laser dynamic modulation, reach the object of the modulation bandwidth that improves micro-cavity laser simultaneously.
Accompanying drawing explanation
Fig. 1 is the stereogram of prior art disc electrode micro-cavity laser;
Fig. 2 is according to the structural representation of embodiment of the present invention annular electrode micro-cavity laser;
Fig. 3 is the structure vertical view of annular electrode micro-cavity laser provided by the invention, and wherein R is disc electrode radius, and r is the inside radius of annular electrode;
Fig. 4 is the structure side view of annular electrode micro-cavity laser provided by the invention;
Fig. 5 A and Fig. 5 B utilize Finite Element Method to carry out prior art disc electrode micro-cavity laser and the embodiment of the present invention annular electrode micro-cavity laser of numerical computations, corresponding charge carrier normalization distribution situation under different inside radius sizes;
Fig. 6 has provided the micro-cavity laser of trying to achieve by analytic solutions near wavelength is 1550 nanometers, and radial quantum number m is respectively 1,5,7 the corresponding normalization radial mode of Whispering-gallery-mode intensity distributions situation;
Fig. 7 provided radius be 15 microns of micro-cavity laser medium wavelengths near 1550 nanometers radial mode width with radial quantum number situation of change;
Fig. 8 A and Fig. 8 B are respectively in prior art disc electrode micro-cavity laser and embodiment of the present invention annular electrode micro-cavity laser, and electrode size changes the impact on pattern horizontal direction light restriction factor;
Fig. 9, for considering carrier diffusion situation, utilizes 15 microns of micro-cavity lasers of laser rate equation simulation radius, obtains the laser small-signal dynamic response adjustment curve in varying level direction light restriction factor situation.
[main element]
100-substrate; 200-micro-cavity laser;
210-lower limit layer; 220-active layer;
230-upper limiting layer; 300-annular electrode.
Embodiment
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.It should be noted that, in accompanying drawing or specification description, similar or identical part is all used identical figure number.The implementation that does not illustrate in accompanying drawing or describe is form known to a person of ordinary skill in the art in affiliated technical field.In addition, although the demonstration of the parameter that comprises particular value can be provided herein, should be appreciated that, parameter is without definitely equaling corresponding value, but can in acceptable error margin or design constraint, be similar to corresponding value.The direction term of mentioning in embodiment, for example " on ", D score, 'fornt', 'back', " left side ", " right side " etc., be only the direction with reference to accompanying drawing.Therefore, the direction term of use is to be not used for limiting the scope of the invention for explanation.
The present invention, by utilizing annular electrode micro-cavity laser, controls charge carrier in micro-cavity laser active area and distributes, and the horizontal direction light restriction factor of controlling inner different light field patterns realizes excitation mode and selects, and can realize micro-cavity laser single mode operation.
In one exemplary embodiment of the present invention, provide a kind of annular electrode micro-cavity laser.Fig. 2 is according to the structural representation of embodiment of the present invention annular electrode micro-cavity laser.Fig. 3 is according to the vertical view of embodiment of the present invention annular electrode micro-cavity laser, and Fig. 4 is according to the end view of embodiment of the present invention annular electrode micro-cavity laser.Please refer to Fig. 2-Fig. 4, the present embodiment annular electrode micro-cavity laser comprises: substrate 100; Micro-cavity laser 200, is formed on substrate 100; The patterned electrodes 300 of the first conduction type, ringwise, is formed at the outer ledge at micro-cavity laser 200 tops; The electrode of the second conduction type, is formed at the side of substrate 100 back sides or micro-cavity laser 200; Wherein, the first conduction type and the second conduction type are respectively one of them in p-type and N-shaped.
Below the various piece of the present embodiment annular micro-cavity laser is elaborated.
The material of substrate 100 can be various III-V family material, for example: InP and GaAs can be also IV family material, and for example: Si, Ge and SiC can be also sapphires.
In the present embodiment, micro-cavity laser is disc.Correspondingly, patterned electrodes 300 is annular, the width d of this annular between 1/8R～1/2R, the internal diameter that r is annular, wherein, the radius that R is micro-cavity laser, R=r+d, its between 1 μ m between 50 μ m.The thickness of patterned electrodes is between 5nm to 500 μ m.In addition, the material of annular electrode 300 can be the metal materials such as Au, Ag, Al, Pt, Cu, or the alloy material of two or more compositions in above-mentioned metal material, can also other have the nonmetallic materials of conduction property.
It should be noted that, the present invention is not limited with above-described embodiment.Micro-cavity laser can also be triangle, square, the forms such as hexagon or octagon.Patterned electrodes is annular corresponding to above-mentioned shape, is distributed in the outer ledge of above-mentioned shape.
In concrete manufacture craft, micro-cavity laser 200 can be prepared by methods such as employing dry etching or wet chemical etch, or prepares by material selective area growth method.And annular electrode can be prepared by the method for the shape of control electrode window.
Fig. 5 A and Fig. 5 B utilize Finite Element Method to carry out prior art disc electrode micro-cavity laser and the embodiment of the present invention annular electrode micro-cavity laser of numerical computations, corresponding charge carrier normalization distribution situation under different inside radius sizes.Wherein, the radius of both micro-cavity lasers 200 is 15 microns, lower limit layer 210, and active layer 220, the thickness of upper limiting layer 230 is respectively 2.6 microns, 0.3 micron, 1.8 microns.Fig. 5 A is the traditional round disc electrode micro-cavity laser calculating, normalization charge carrier distribution situation in corresponding active area in the time that electrode radius is respectively 9,11 and 13 microns.From Fig. 5 A, more can find out, the charge carrier that disc electrode pair is answered distributes and mainly concentrates on center, active area, and along with the increase of radius, the peak that charge carrier distributes is to microcavity Boundary Moving, and charge carrier distributes and becomes evenly.Fig. 5 B is annular electrode micro-cavity laser, and annular electrode outer radius is 15 microns, when corresponding interior ring radius is 9 microns, 11 microns, 13 microns, and corresponding active area normalization charge carrier distribution situation.The corresponding charge carrier distribution of microdisk laser that can find out annular electrode mainly concentrates on microcavity boundary, and charge carrier distribution situation can be controlled in the position of change annulus.
Fig. 6 has provided the micro-cavity laser of trying to achieve by analytic solutions near wavelength is 1550 nanometers, and radial quantum number m is respectively 1,5,7 the corresponding normalization radial mode of Whispering-gallery-mode intensity distributions situation.Wherein, micro-cavity laser radius is 15 microns, and refractive index is 3.2, and surrounding medium refractive index is 1.Can find out that when radial quantum number is low, pattern is mainly distributed in boundary, along with the increase of radial quantum number, corresponding mode profile can move to microcavity center, and mode width can corresponding broadening simultaneously.
Fig. 7 provided radius be 15 microns of micro-cavity laser medium wavelengths near 1550 nanometers radial mode width with radial quantum number situation of change.As seen from Figure 7, when radial quantum number increases, mode intensity width increases gradually.Mode width corresponding to 1 rank pattern is 1 micron, and in the time that radial quantum number increases, mode width increases gradually, and mode width corresponding to 12 rank patterns is 5.2 microns.
Fig. 8 A and Fig. 8 B are respectively in prior art disc electrode micro-cavity laser and embodiment of the present invention annular electrode micro-cavity laser, and electrode size changes the impact on pattern horizontal direction light restriction factor.There is higher horizontal direction light restriction factor compared with wide mode.Because circular microcavity pattern is mainly distributed in microcavity border, annular electrode obviously can be realized higher horizontal direction light restriction factor.Be the pattern of 4 microns for mode width, horizontal direction light restriction factor can be greater than 0.6.
Fig. 9 has provided and has considered in carrier diffusion situation, utilizes the dynamic characteristic of 15 microns of micro-cavity lasers of laser rate equation simulation radius, obtains the laser small-signal dynamic response adjustment curve in varying level direction light restriction factor situation.Can find out and work as, the restriction of horizontal direction light increases the dynamic modulation bandwidth that can improve disc electrode micro-cavity laser, and modulated response curve is more smooth simultaneously, is conducive to the digital signal modulated of laser.
Can be found out by Fig. 5 A, Fig. 5 B, Fig. 8 A and Fig. 8 B, can control by controlling the position of graphical contact electrode 300 and figure the light restriction factor of the horizontal direction of different mode, improve the space coincidence degree of active area charge carrier distribution and excitation mode, contribute to realize single module lasing of micro-cavity laser., can be found out by Fig. 8 A, Fig. 8 B and Fig. 9 meanwhile, can reduce the diffusion effect of charge carrier by controlling the position of graphical contact electrode and figure, be conducive to improve the direct current modulation speed of micro-cavity laser.
So far, by reference to the accompanying drawings the present embodiment be have been described in detail.Describe according to above, those skilled in the art should have clearly understanding to rotary resonance type three-dimensional electric field sensor of the present invention.
In addition, the above-mentioned definition to each element and method is not limited in various concrete structures, shape or the mode in embodiment, mentioned, and those of ordinary skills can change simply or replace it.
In sum, annular electrode micro-cavity laser utilization of the present invention changes the distribution situation of patterned electrodes, realize the control in distribution radially to active area charge carrier, thereby control the light restriction factor of the horizontal direction of different mode, excitation mode optical field distribution and charge carrier are distributed spatially have larger overlapping, obtain higher gain and then realize single module lasing.Can reduce the impact of carrier diffusion effect on micro-cavity laser dynamic modulation, reach the object of the modulation bandwidth that improves micro-cavity laser simultaneously.
Above-described specific embodiment; object of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the foregoing is only specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (10)
1. an annular electrode micro-cavity laser, is characterized in that, comprising:
Substrate (100);
Micro-cavity laser (200), is formed on described substrate (100);
The patterned electrodes (300) of the first conduction type, its material is metal, its shape ringwise, is formed at the outer ledge at described micro-cavity laser (200) top;
The electrode of the second conduction type, in the time that described substrate (100) is dielectric substrate, is formed at the side of described micro-cavity laser (200); In the time that described substrate (100) is conductive substrates, be formed at the side of described substrate (100) back side or described micro-cavity laser (200);
Wherein, the first conduction type and the second conduction type are respectively one of them in p-type and N-shaped.
2. annular electrode micro-cavity laser according to claim 1, is characterized in that, described micro-cavity laser is disc, triangle, square, hexagon or octagon;
The patterned electrodes of described the first conduction type is for being formed at this disc, triangle, square, the annular of the outer ledge at hexagon or octagon micro-cavity laser top.
3. annular electrode micro-cavity laser according to claim 1, is characterized in that, described micro-cavity laser is disc, and the patterned electrodes of described the first conduction type is the annular that is formed at this disc micro-cavity laser outer ledge.
4. annular electrode micro-cavity laser according to claim 3, is characterized in that, the width d of described annular between 1/8R～1/2R, wherein, the radius that R is micro-cavity laser.
5. annular electrode micro-cavity laser according to claim 4, is characterized in that, described R is between 1 μ m between 50 μ m, and the thickness of the patterned electrodes of described the first conduction type is between 5nm to 500 μ m.
6. annular electrode micro-cavity laser according to claim 1, is characterized in that, the material of described annular electrode is selected from the alloy of one or more compositions in following material: Au, Ag, Al, Pt, Cu.
7. according to the annular electrode micro-cavity laser described in any one in claim 1 to 6, it is characterized in that, described micro-cavity laser comprises from bottom to top: lower limit layer (210), active layer (220) and upper limiting layer (230).
8. annular electrode micro-cavity laser according to claim 7, is characterized in that, described lower limit layer (210) and upper limiting layer (230) are identical III-V family materials limitations layer.
9. annular electrode micro-cavity laser according to claim 7, is characterized in that, the material of described active layer is InGaAs, InGaAsP or AlGaInAs.
10. according to the annular electrode micro-cavity laser described in any one in claim 1 to 6, it is characterized in that, the material of described substrate is: sapphire, III-V family material or IV family material.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104934840A (en) * | 2015-06-25 | 2015-09-23 | 北京无线电计量测试研究所 | Microwave oscillator based on sapphire filter |
| CN104078839B (en) * | 2014-06-26 | 2017-04-19 | 中国科学院半导体研究所 | Optical pulse synchronizing signal source based on waveguide coupling microdisk photon molecular lasers |
| CN104377546B (en) * | 2014-12-08 | 2018-03-20 | 长春理工大学 | Oval ring chamber micro-cavity laser with high resistance area |
| CN108336642A (en) * | 2018-02-11 | 2018-07-27 | 中国科学院苏州纳米技术与纳米仿生研究所南昌研究院 | A kind of nitride-based semiconductor micro-cavity laser structure of electrical pumping lasing and preparation method thereof |
| CN114256738A (en) * | 2021-11-10 | 2022-03-29 | 南京邮电大学 | Electric pump nitride suspended waveguide micro-laser and preparation method thereof |
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| CN101145674A (en) * | 2006-09-15 | 2008-03-19 | 三星电子株式会社 | Vertical cavity surface emitting laser and fabricating method thereof |
| CN101867147A (en) * | 2009-04-15 | 2010-10-20 | 中国科学院半导体研究所 | Quantum cascade laser regular polygonal microcavity laser and manufacturing method thereof |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104078839B (en) * | 2014-06-26 | 2017-04-19 | 中国科学院半导体研究所 | Optical pulse synchronizing signal source based on waveguide coupling microdisk photon molecular lasers |
| CN104377546B (en) * | 2014-12-08 | 2018-03-20 | 长春理工大学 | Oval ring chamber micro-cavity laser with high resistance area |
| CN104934840A (en) * | 2015-06-25 | 2015-09-23 | 北京无线电计量测试研究所 | Microwave oscillator based on sapphire filter |
| CN108336642A (en) * | 2018-02-11 | 2018-07-27 | 中国科学院苏州纳米技术与纳米仿生研究所南昌研究院 | A kind of nitride-based semiconductor micro-cavity laser structure of electrical pumping lasing and preparation method thereof |
| CN114256738A (en) * | 2021-11-10 | 2022-03-29 | 南京邮电大学 | Electric pump nitride suspended waveguide micro-laser and preparation method thereof |
| CN114256738B (en) * | 2021-11-10 | 2023-09-12 | 南京邮电大学 | Electric pump nitride suspended waveguide micro-laser and preparation method thereof |
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Application publication date: 20140521 |