0.87μm脉冲半导体激光器研究
|
摘要
0.84～0.90μm波段的脉冲半导体激光器可用于激光测距、激光引信、短途通信等系统，随着系统可移动、小型化的迅速发展，如何降低作为系统光源的半导体激光器的阀值电流密度，提高其微分量子效率和输出功率等成为主要的研究课题，传统的液相外延工艺制作的体材料激光器已不能满足要求，而量子阱结构的采用可改进器件的许多特性：在量子阱激光器中，由于它的极薄的有源层和各向异性的光传输矩阵元使其更容易实现单TE基横模和侧模；在极大地降低阀值电流密度方面有了最为成功的改进；GaA1As／GaAs量子阱激光器由于具有阶梯态密度，其T_0大于200K，大约是双异质结激光器的两倍，量子阱激光器已实现了高的功率输出。工艺较为成熟的GaA1As／GaAs量子阱结构激光器的发射波长主要在0.78～0.81μm范围，这类器件在低阀值电流密度，微分量子效率和可靠性等方面仍存在一定局限，针对这些问题，我们进行了0.87μm脉冲半导体激光器的研究。
本文较为深入地论述了0.87μm脉冲半导体激光器的研制过程。其中对量子阱的限制态、态密度和限制态的集居数等进行了理论分析，采用叠层迭代法和扩展抛物近似对GRIN-SCH-SQW中的光限制因子、波导模式、模折射率、远场角等也进行了有益的推导和计算。对器件参数设计、结构设计，以及材料生长、欧姆接触、端面镀膜等工艺进行了重点讨论。在对激光器的主要参数如光增益、应变层的厚度、激射波长、阈值电流密度、输出功率等分析和计算的基础上，优化了器件结构参数和工艺参数，该器件结构采用InGaA1As／GaAs梯度折射率分别限制(GRIN-SCH)脊形波导应变单量子阱。有源层In组分为0.13，A1组分为0.09，阱宽d_w为8nm。包层A1组分为0.60，厚度为1.5μm，脊形波导条宽300μm,高0.9μm，腔长1000μm。获得了波长0.87±0.03μm,脉冲功率大于30W(I=10A，f=100kHz，τ=50ns)，光谱宽度小于4nm的器件。最后分析了器件的可靠性，给出了器件的主要特性参数和曲线。该器件性能参数达到项目设计要求。
对于0.87±0.03μm波段的大功率激光器，目前，这种高重复频率列阵结构，尚未查到国内外有关资料报道。在国内，作者首次对0.87±0.03μm波长梯度折射率分别限制(CRIN-SCH)脊形波导InGaA1As／GaAs应变单量子阱激光器的材料参数、结构参数进行了设计；并研究出0.87μm脉冲半导体激光器；摸索出了目前条件较佳的端面镀膜工艺参数；P面加固的新工艺的采用，既降低了欧姆接触电阻，又满足了压焊的要求，提高了器件的成品率。
Pulse semiconductor lasers operating in the range of 0.84~0.90um can be used in the systems of laser measure, laser detonator,short -range communication,etc..Now much research efforts are focused on reducing the threshold current density, increasing the differential efficiency and output light power of the semiconductor lasers,which are used as light sources in the system that have to meet demands of portability and miniature,while the bulk semiconductor lasers by the conventional LPE fabrication don't meet the needs of the development.The semiconductor QW lasers have been applied to improve many of device characteristic single TE fundamental transverse and lateral modes are more readily realized in QW lasers for their ultrathih active layers and anisotropic optical transition matrix elements;The most successful improvement in this field is the drastically reduction of lasing threshold;The T0 of GaAlAs/GaAs QW lasers is increased to more than 200K,about 2-fold of DH lasers due to the step-like DOS; High laser output power of QW lasers have been realized. The GaAlAs/GaAs QW lasers of the state-of-art work in the wavelength range of 0.78-0.8 l(am.But this kind of QW lasers still remain to be improved in such parameters as threshold current density, differential efficiency and lifetime.Dealing with the problems relating these parameters are main efforts of the author.
In this paper, a procedure of the 0.87um pulse semiconductor laser is discussed specially .The Confined states, density of states and populations on confined states in QW are given by analysis. The profitable deduction and calculation for confinement factor, waveguide model, model refractive index, farfield angle are shown by the methed of lamination-iteration and the extended parabolic approximation. We focus on the design of parameter and structure of the device, and on the technology of material growth, ohmic contact, mirror facet coating. The optimum structure and technology parameters are given on the basis of synthetical analysis and calculation of laser's important characteristics, such as gain .critical thickness, peak wavelength, threshold current density, output power and so on. Used graded-index separate-confinement heterostructure (GRIN-SCH) InGaAlAs/GaAs ridge waveguide(RWG) strained single-quantum-well(SQW), which active region In and Al mole fraction are 0.13, 0.09, respectively. The cladding layer Al mole fraction is 0.60, thickness of the well is 8nm, cladding thickness is l.Sum.Width, height and length of ridge waveguide are 300um, 0.9um and 1000u.m, respectively. We obtained the devices with 0.87 + 0.03um lasing wavelength ,more than 30W peak output power(I=10A,f=100kHz, T =50ns), less than 4nm spectral linewidth. Finally its reliability and photoelecteicity characteristics and curve are given.The fabricated devices demonstrated performances as expected.
Up till now the author didn't find any reports on the high repetition frequency and power array laser emitting at 0.87 ?0.03um The author proposed a design of GRIN-SCH InGaAlAs/GaAs RWG strained SQW lasers for the first time in the home country, and manufactured the 0.87um pulse semiconductor lasers , and determined the optimal process parameters for mirror facet coating ,and introduced the innovative p-side enhancement process which resulted in reduced contact resistance , more reliable soldering and better fabrication efficiecy in the manufacture of the 0.87um pulse semiconductor lasers.
本文较为深入地论述了0.87μm脉冲半导体激光器的研制过程。其中对量子阱的限制态、态密度和限制态的集居数等进行了理论分析，采用叠层迭代法和扩展抛物近似对GRIN-SCH-SQW中的光限制因子、波导模式、模折射率、远场角等也进行了有益的推导和计算。对器件参数设计、结构设计，以及材料生长、欧姆接触、端面镀膜等工艺进行了重点讨论。在对激光器的主要参数如光增益、应变层的厚度、激射波长、阈值电流密度、输出功率等分析和计算的基础上，优化了器件结构参数和工艺参数，该器件结构采用InGaA1As／GaAs梯度折射率分别限制(GRIN-SCH)脊形波导应变单量子阱。有源层In组分为0.13，A1组分为0.09，阱宽d_w为8nm。包层A1组分为0.60，厚度为1.5μm，脊形波导条宽300μm,高0.9μm，腔长1000μm。获得了波长0.87±0.03μm,脉冲功率大于30W(I=10A，f=100kHz，τ=50ns)，光谱宽度小于4nm的器件。最后分析了器件的可靠性，给出了器件的主要特性参数和曲线。该器件性能参数达到项目设计要求。
对于0.87±0.03μm波段的大功率激光器，目前，这种高重复频率列阵结构，尚未查到国内外有关资料报道。在国内，作者首次对0.87±0.03μm波长梯度折射率分别限制(CRIN-SCH)脊形波导InGaA1As／GaAs应变单量子阱激光器的材料参数、结构参数进行了设计；并研究出0.87μm脉冲半导体激光器；摸索出了目前条件较佳的端面镀膜工艺参数；P面加固的新工艺的采用，既降低了欧姆接触电阻，又满足了压焊的要求，提高了器件的成品率。
Pulse semiconductor lasers operating in the range of 0.84~0.90um can be used in the systems of laser measure, laser detonator,short -range communication,etc..Now much research efforts are focused on reducing the threshold current density, increasing the differential efficiency and output light power of the semiconductor lasers,which are used as light sources in the system that have to meet demands of portability and miniature,while the bulk semiconductor lasers by the conventional LPE fabrication don't meet the needs of the development.The semiconductor QW lasers have been applied to improve many of device characteristic single TE fundamental transverse and lateral modes are more readily realized in QW lasers for their ultrathih active layers and anisotropic optical transition matrix elements;The most successful improvement in this field is the drastically reduction of lasing threshold;The T0 of GaAlAs/GaAs QW lasers is increased to more than 200K,about 2-fold of DH lasers due to the step-like DOS; High laser output power of QW lasers have been realized. The GaAlAs/GaAs QW lasers of the state-of-art work in the wavelength range of 0.78-0.8 l(am.But this kind of QW lasers still remain to be improved in such parameters as threshold current density, differential efficiency and lifetime.Dealing with the problems relating these parameters are main efforts of the author.
In this paper, a procedure of the 0.87um pulse semiconductor laser is discussed specially .The Confined states, density of states and populations on confined states in QW are given by analysis. The profitable deduction and calculation for confinement factor, waveguide model, model refractive index, farfield angle are shown by the methed of lamination-iteration and the extended parabolic approximation. We focus on the design of parameter and structure of the device, and on the technology of material growth, ohmic contact, mirror facet coating. The optimum structure and technology parameters are given on the basis of synthetical analysis and calculation of laser's important characteristics, such as gain .critical thickness, peak wavelength, threshold current density, output power and so on. Used graded-index separate-confinement heterostructure (GRIN-SCH) InGaAlAs/GaAs ridge waveguide(RWG) strained single-quantum-well(SQW), which active region In and Al mole fraction are 0.13, 0.09, respectively. The cladding layer Al mole fraction is 0.60, thickness of the well is 8nm, cladding thickness is l.Sum.Width, height and length of ridge waveguide are 300um, 0.9um and 1000u.m, respectively. We obtained the devices with 0.87 + 0.03um lasing wavelength ,more than 30W peak output power(I=10A,f=100kHz, T =50ns), less than 4nm spectral linewidth. Finally its reliability and photoelecteicity characteristics and curve are given.The fabricated devices demonstrated performances as expected.
Up till now the author didn't find any reports on the high repetition frequency and power array laser emitting at 0.87 ?0.03um The author proposed a design of GRIN-SCH InGaAlAs/GaAs RWG strained SQW lasers for the first time in the home country, and manufactured the 0.87um pulse semiconductor lasers , and determined the optimal process parameters for mirror facet coating ,and introduced the innovative p-side enhancement process which resulted in reduced contact resistance , more reliable soldering and better fabrication efficiecy in the manufacture of the 0.87um pulse semiconductor lasers.
引文
[1．1] 亨利．克雷歇尔，J.K.巴特勒《半导体激光器和异质结发光二极管》，国防工业出版社，1983，pp245—247．
[1．2] U. Koren, B.I. Miller, "Low Internal Loss Separate Confinement(SC)Hetero-structure InGaAs/InGaAsP Quantum Well Laser." Appl. Phys. Lett. 1987, Vol. 51 pp. 1744.
[1． 3] A.Kasukawa,Y.Imato,T.Makino."1． 3um InGaAsP/InP BH GRIN-SC Multi-Quantum Well Lasers Entirely Grown By MOCVD." Electron.Lett.1989,Vol.25 pp.104．
[1． 4] P.I.A.Thi js,T.Van.Dongen."High Quantum Efficiency High Power Modulation Doped GalnaAs Strained-Layer QW Laser Diodes Emitting at 1． 5um" Electron.Lett. 1989,Vol.25 pp.1735．
[1． 5] U.Koren,M.Oron,M.G.Young."Low Threshold High Efficient Strined Quantum Well Lasers at 1． 5um" Electron.Lett.1990,Vol.26 pp.465．
[1． 6] C.A.Wang.J.N.Walpole,H.K.Choi,and L.J.Missaggia. " AlInGaAs-AlGaAs atrained single-quantum-well diode laser" ,IEEE Photon Technol.Lett. 1991,3,pp.4-5
[1． 7] L.buydens,P.Demeester,M,van Achere,and P.van Daele." AlGaInAs-AlGaAs SSOW GRINSCH lasers for the wavelength region between 800 and 870nm",Electron.Lett. 1991,Vol.27 (8) ,pp.618-620．
[1． 8] C.A.Wang.J.N.Walpole,L.J.Missaggia,J.P.Donnelly,andH.K.Chol."AlInGaAs/Al-GaAs separate-continement heterostructure strained single-quantum-well diode lasers grown by organometallic vapor phase epitaxy" ,Appl.Phys,Lett.1991,Vol.58, pp.2208-2210．
[2． 1] R.Dingle,Festkoperprobleme XV 1975,21-48．
[2． 2] J.SBiakemore,J.Appl.Phys.,1982,Vol.53(10) .
[2． 3] C.Z.Guo,X.M.Yang,Proceeding of the 7th National Conference on the Physics of Semiconductors,Oct.31-Nov.3． 1989,Shanghai; Research and Progress of Solid State Electronics,Nov.1989,Vol.9(4) pp.408．
[2． 4] H.C.Casey,Jr.,N.B.Panish,Heteeeerostructure laser,New York,Academic, 1978．
[2． 5] C.Z.Guo,Semiconductor Laser Mode Theory,The People's Post and Communications Publisher,Beijing ,Dec.1989．
[2． 6] W.T.Tsang,IEEE J.Quantum Electron.1984,Vol22(10) pp.1119-1131．
[2． 7] C.Z.Guo,X.C.Bai,S.L.Chen,2nd National Conference on Semiconductor Superlattice Microstructures,Sept.1988,Beijing,p.2; C.Z.Guo,S.L.Chen,National
Conference on Luminescence and Photoelectric Properties of Semiconductor QW & SL, Oct. 1988, Hefei; C.Z. Guo, S.L. Chen, Chin. J. Semicond., 1989, Vol.10(12) pp. 892—903.
[2．8] C.Z. Guo, S.L. Chen, Chin. J. Semicond., Mar. 1988, Vol. 9, (2)pp. 135-149;Chin.Phys., 1988Vol. 8.
[2．9] F.C. Prince, T.J.S. Mattos, N.B. Patel, D. Kasemset, C.S. Hong, IEEE J. Quantum Electron.,1985, Vol. 21(6)pp. 634-639.
[2．10] S.M. Rytov, Soviet Physics, JETP, May. 1956, Vol. 2(3)pp. 466-475.
[2．11] J.W. Matthews etal. J. Crystal Growth, 1974 Vol. 27. pp. 322.
[2．12] R. People etal. Appl. Phys. Lett, 1985, Vol. 47. pp. 322
[2．13] S.L. Chuang, Physics of Optoelectronic Devices. New York, Wiley, 1995.
[2．14] K.H. Hellwege, Ed.,Landolt-Bornstein Numerical Data and Functional Relationships in Science and Technology. Berlin, Germany:Spriner, 1982, new series, group Ⅲ, 17a;groups Ⅲ-Ⅴ 22a, Berlin:Springer, 1986.
[2．15] W.W Andccson, IEEE J Quantum Electron, 1965, No. 1 pp. 288.
[2．16] M.J. Adamser J. Appl Phys, 1969, Vol. 42 pp. 1549.
[2．17] M.B. Panish and H.C. Caseg J. Appl Phys, 1969, Vol. 40 pp. 163.
[2．18] 廖柯，张道银．“镜面镀膜技术在GaAlAs可见光激光器中的应用”第五届全国光纤通信学术会论文集．天津．May.1991，pp．162．
[2．19] 罗江才，朱自文等．“1.3 μm InGaAsP／InP LD SLD和LED的介质镀膜”半导体光电，1995，Vol．16(2)pp．131—134．
[2．20] 郝尧“优化反射率以增强半导体激光器输出功率”半导体光电，1995，Vol．16(2)．pp．131—134．
[2．21] Toshio higashi et al. "Optimum asymmetric mirror facet structure for High-efficienty semiconductor lasers" IEEE J. Quantum Electron, 1993, Vol. 29 (6) pp1981—1982.
[3．1] J.W. Matthews and A.E. Blakeslee, J. Cryst. Growth ,1974, Vol. 27. pp. 118.
[3．2] Axel. R. Reisinger. "Cavity length dependence of the threshold behavior in thin quantum well semconductor lasers" IEEE. J. Ouantum Electron,1987, Vol. 23 (6) pp. 993—999.
[3．3] 亨利．克雷歇尔，J.K.巴特勒《半导体激光器和异质结发光二极管》，国防工业出版社，1983，pp．280．
[3．4] 任大翠，王玉霞等，“量子阱激光器的阈值电流和外量子效率”半导体光电，1998，Vol。19(5)．pp．294—299．
[3．5] 刘恩科，朱秉升 《半导体物理学》，国防工业出版社，1984，pp．201．
[4．1] ATC 《Semiconductor Device mirror facet coating》 pp. 25—30.
[1．2] U. Koren, B.I. Miller, "Low Internal Loss Separate Confinement(SC)Hetero-structure InGaAs/InGaAsP Quantum Well Laser." Appl. Phys. Lett. 1987, Vol. 51 pp. 1744.
[1． 3] A.Kasukawa,Y.Imato,T.Makino."1． 3um InGaAsP/InP BH GRIN-SC Multi-Quantum Well Lasers Entirely Grown By MOCVD." Electron.Lett.1989,Vol.25 pp.104．
[1． 4] P.I.A.Thi js,T.Van.Dongen."High Quantum Efficiency High Power Modulation Doped GalnaAs Strained-Layer QW Laser Diodes Emitting at 1． 5um" Electron.Lett. 1989,Vol.25 pp.1735．
[1． 5] U.Koren,M.Oron,M.G.Young."Low Threshold High Efficient Strined Quantum Well Lasers at 1． 5um" Electron.Lett.1990,Vol.26 pp.465．
[1． 6] C.A.Wang.J.N.Walpole,H.K.Choi,and L.J.Missaggia. " AlInGaAs-AlGaAs atrained single-quantum-well diode laser" ,IEEE Photon Technol.Lett. 1991,3,pp.4-5
[1． 7] L.buydens,P.Demeester,M,van Achere,and P.van Daele." AlGaInAs-AlGaAs SSOW GRINSCH lasers for the wavelength region between 800 and 870nm",Electron.Lett. 1991,Vol.27 (8) ,pp.618-620．
[1． 8] C.A.Wang.J.N.Walpole,L.J.Missaggia,J.P.Donnelly,andH.K.Chol."AlInGaAs/Al-GaAs separate-continement heterostructure strained single-quantum-well diode lasers grown by organometallic vapor phase epitaxy" ,Appl.Phys,Lett.1991,Vol.58, pp.2208-2210．
[2． 1] R.Dingle,Festkoperprobleme XV 1975,21-48．
[2． 2] J.SBiakemore,J.Appl.Phys.,1982,Vol.53(10) .
[2． 3] C.Z.Guo,X.M.Yang,Proceeding of the 7th National Conference on the Physics of Semiconductors,Oct.31-Nov.3． 1989,Shanghai; Research and Progress of Solid State Electronics,Nov.1989,Vol.9(4) pp.408．
[2． 4] H.C.Casey,Jr.,N.B.Panish,Heteeeerostructure laser,New York,Academic, 1978．
[2． 5] C.Z.Guo,Semiconductor Laser Mode Theory,The People's Post and Communications Publisher,Beijing ,Dec.1989．
[2． 6] W.T.Tsang,IEEE J.Quantum Electron.1984,Vol22(10) pp.1119-1131．
[2． 7] C.Z.Guo,X.C.Bai,S.L.Chen,2nd National Conference on Semiconductor Superlattice Microstructures,Sept.1988,Beijing,p.2; C.Z.Guo,S.L.Chen,National
Conference on Luminescence and Photoelectric Properties of Semiconductor QW & SL, Oct. 1988, Hefei; C.Z. Guo, S.L. Chen, Chin. J. Semicond., 1989, Vol.10(12) pp. 892—903.
[2．8] C.Z. Guo, S.L. Chen, Chin. J. Semicond., Mar. 1988, Vol. 9, (2)pp. 135-149;Chin.Phys., 1988Vol. 8.
[2．9] F.C. Prince, T.J.S. Mattos, N.B. Patel, D. Kasemset, C.S. Hong, IEEE J. Quantum Electron.,1985, Vol. 21(6)pp. 634-639.
[2．10] S.M. Rytov, Soviet Physics, JETP, May. 1956, Vol. 2(3)pp. 466-475.
[2．11] J.W. Matthews etal. J. Crystal Growth, 1974 Vol. 27. pp. 322.
[2．12] R. People etal. Appl. Phys. Lett, 1985, Vol. 47. pp. 322
[2．13] S.L. Chuang, Physics of Optoelectronic Devices. New York, Wiley, 1995.
[2．14] K.H. Hellwege, Ed.,Landolt-Bornstein Numerical Data and Functional Relationships in Science and Technology. Berlin, Germany:Spriner, 1982, new series, group Ⅲ, 17a;groups Ⅲ-Ⅴ 22a, Berlin:Springer, 1986.
[2．15] W.W Andccson, IEEE J Quantum Electron, 1965, No. 1 pp. 288.
[2．16] M.J. Adamser J. Appl Phys, 1969, Vol. 42 pp. 1549.
[2．17] M.B. Panish and H.C. Caseg J. Appl Phys, 1969, Vol. 40 pp. 163.
[2．18] 廖柯，张道银．“镜面镀膜技术在GaAlAs可见光激光器中的应用”第五届全国光纤通信学术会论文集．天津．May.1991，pp．162．
[2．19] 罗江才，朱自文等．“1.3 μm InGaAsP／InP LD SLD和LED的介质镀膜”半导体光电，1995，Vol．16(2)pp．131—134．
[2．20] 郝尧“优化反射率以增强半导体激光器输出功率”半导体光电，1995，Vol．16(2)．pp．131—134．
[2．21] Toshio higashi et al. "Optimum asymmetric mirror facet structure for High-efficienty semiconductor lasers" IEEE J. Quantum Electron, 1993, Vol. 29 (6) pp1981—1982.
[3．1] J.W. Matthews and A.E. Blakeslee, J. Cryst. Growth ,1974, Vol. 27. pp. 118.
[3．2] Axel. R. Reisinger. "Cavity length dependence of the threshold behavior in thin quantum well semconductor lasers" IEEE. J. Ouantum Electron,1987, Vol. 23 (6) pp. 993—999.
[3．3] 亨利．克雷歇尔，J.K.巴特勒《半导体激光器和异质结发光二极管》，国防工业出版社，1983，pp．280．
[3．4] 任大翠，王玉霞等，“量子阱激光器的阈值电流和外量子效率”半导体光电，1998，Vol。19(5)．pp．294—299．
[3．5] 刘恩科，朱秉升 《半导体物理学》，国防工业出版社，1984，pp．201．
[4．1] ATC 《Semiconductor Device mirror facet coating》 pp. 25—30.