In summary, we have studied the high speed performance of vertical-cavity surface-emitting laser. The high speed performance was improved through modifying the gain region, proton-implantation process, and tapered oxide layer.
In chapter 4, we present the fabrication and characteristics of high performance 850 nm InGaAsP/InGaP strain-compensated MQWs vertical-cavity surface-emitting lasers. The InGaAsP/InGaP MQWs composition was optimized through theoretical calculations and the growth condition was optimized using photoluminescence. These VCSELs exhibited superior performance with characteristics threshold currents ~0.4 mA, and the slope efficiencies ~ 0.6 mW/mA. The threshold current change with temperature is less than 0.2 mA and the slope efficiency drops less than ~30% when the substrate temperature is raised from room temperature to 85oC. High modulation bandwidth of 14.5 GHz and modulation current efficiency factor of 11.6 GHz/(mA)1/2 are demonstrated. We have also accumulated life test data up to 1000 hours at 70oC/8mA. Although the BCB planaried process has very low capacitance, the cost was relatively high due the lower yield. We adapted a simple, reliable process by proton implantation to cut down the device capacitance. In chapter 5, we reported the high speed performance of 850nm oxide-confined vertical cavity surface emitting lasers (VCSELs) with planar process and reduced parasitic capacitance. The parasitic capacitance of VCSELs was reduced using additional proton implantation. The small signal modulation bandwidth which was restricted by electrical parasitic capacitance expanded from 2.3 GHz to 9 GHz after proton implantation. To investigate the extrinsic bandwidth limitation of the oxide VCSELs, an equivalent circuit for the VCSEL impedance was introduced. The reflection coefficient showed that the electric parasitic pole exceeded 20 GHz. The eye diagram of VCSEL with reduced parasitic capacitance operating at 10Gbps with 6mA bias and 6dB extinction ratio showed a very clean eye with a jitter of less than 20 ps. This simple method can be applied to mass production with low cost.
In the last part, we present the improved oxide-implanted VCSELs utilizing the tapered oxide layer. The VCSELs exhibited similar static performance, but superior modulation bandwidth up to 13.2 GHz, compared with conventional blunt oxide VCSELs. The damping rate was reduced two times in the tapered oxide VCSEL and therefore enhanced the maximal modulation bandwidth. A very clean eye was demonstrated from improved VCSEL with rising time of 26 ps, falling time of 40 ps and jitter of less than 20 ps, operating at 10Gb/s
with 6mA bias and 6dB extinction ratio. A comprehensive small signal measurement and analysis was conducted. Based on the equivalent circuit model, the extrinsic bandwidth limitation of the tapered oxide VCSELs was determined.
Curriculum Vita
Name: Mr. Ya-Hsien Chang Place of Birth: Taipei, Taiwan Date of Birth: Jan 12, 1976
Electronic Mail: [email protected] Education:
Ph.D. Electro-Optical Engineering, National Chiao Tung University, Taiwan M.S. Electronics, National Tsing-Hua University, Taiwan
B.S. Electronic Engineering, National Tsing-Hua University, Taiwan
Areas of Special Interest:
High speed Vertical-Cavity Surface-Emitting Laser Optical / RF photonics measurement
Optical microscopy and micro-photoluminescence
Title of Ph.D. Thesis:
High speed characteristics of Vertical-Cavity Surface-Emitting Laser
RECENT PUBLICATIONS ( 2003.10-2005.6 ) Ya Hsien Chang (張亞銜) I. JOURNAL PAPERS:
2005
1. Ya-Hsien Chang, Hao-Chung Kuo*, Yi-An Chang, Jung-Tang Chu, Min-Ying Tsai and Shing-Chung Wang, “10 Gbps InGaAs:Sb-GaAs-GaAsP Quantum Well Vertical Cavity Surface Emitting Lasers with 1.27 µm Emission Wavelengths”, J. J.
Appl. Phys. 44(4B), 2556-2559 (2005)
2. Y. H. Chang, T. H. Hsueh, F. I. Lai, C. W. Chang, C. C. Yu, H. W. Huang, C. F.
Lin, H. C. Kuo and S. C. Wang,” Fabrication and micro-photoluminescence investigation of Mg-doped gallium nitride Nanorods “ J. J. Appl. Phys. J. J. Appl.
Phys. 44(4B), 2657-2660, (2005)
3. Y. H. Chang, H. C. Kuo, Fang-I Lai, K. F. Tzeng, H. C. Yu, C. P. Sung, H. P. Yang and S. C. Wang, “High Speed (>13GHz) Modulation of 850nm Vertical Cavity Surface Emitting Lasers (VCSELs) with Tapered Oxide Confined Layer”, IEE Proc.-Optoelectron., Vol. 152(3), pp. 170-173, 2005
4. Hao-Chung Kuo, Ya-Hsien Chang, Yi-An Chang, Jung-Tang Chu, Min-Ying Tsai, and Shing-Chung Wang,” Single mode 1.27-µm InGaAs:Sb-GaAs-GaAsP Quantum Well Vertical Cavity Surface Emitting Lasers” IEEE J. Selected Topic of Quantum Electronics, 11(1) p.p 121-126 (2005)
5. H. C. Kuo, Y. H. Chang, H. H. Yao, Y. A. Chang, M. Y. Tsai, and S. C. Wang,”
High-Speed modulation of InGaAs:Sb-GaAs-GaAsP Quantum Well Vertical Cavity Surface Emitting Lasers with 1.27 µm Emission Wavelength” Photonics Technology Letter, 17(3) p.p 528-530 (2005).
6. H. C. Kuo, Fang-I Lai, Y. H. Chang, M. Y. Tsai, S. Y. Kuo, S. C. Wang, N. Tansu, Jeng-Ya Yeh and Luke J. Maws, ”Temperature dependent photoluminescence of highly strained InGaAsN/GaAs Quantum Well ( λ=1.28-1.45 µm) with GaAsP strain-compensated layer”, accepted by J. J. Appl. Phys.
7. H. C. Kuo, H. H. Yao, Y. S. Chang, Y. A. Chang and S. C. Wang,” MOCVD growth of InGaAs:Sb-GaAs-GaAsP Quantum Well Vertical Cavity Surface Emitting Lasers with 1.27 µm Emission Wavelength”, J. of Crystal Growth 272(1-4), 538-542 (2004).
8. Tao-Hung Hsueh, Hung-Wen Huang, Chih-Chiang Kao, Ya-Hsien Chang, Miao-Chia. Ou-Yang, Hao-Chung Kuo, Jinn-Kong Sheu, and Shing-Chung Wang,
“Fabrication and Characterization of InGaN/GaN Multiple Quantum Wells Embedded within Nanorods”, J. J. Appl. Phys. 44(4B), 2661-2663 (2005)
9. Yang HPD, Lai FI, Chang YH, Yu HC, Sung CP, Kuo HC, Wang SC, Lin SY, Chi JY, “Single-mode (SMSR>40dB) proton-implanted photonic crystal vertical-cavity surface-emitting lasers” 41 (6): 326-328 (2005)
2004
1. Y. H. Chang, H. C. Kuo, F. I. Lai, T. H. Hseuh and S. C. Wang, “Fabrication of high speed InGaAsP/InGaP strain-compensated VCSELs with 850 nm emission wavelength” published in IEEE J. of Lightwave Technologies , vol. 22(12) pp.
2828, 2004
2. Y H Chang, Fang-I Lai, C Y Lu, H C Kuo, H C Yu, C P Sung, H P Yang, S C Wang, ” High-speed (>10 Gbps) 850 nm oxide-confined vertical cavity surface emitting lasers (VCSELs) with a planar process and reduced parasitic capacitance,” Semiconductor Science and Technology, 19 (7): L74-L77 2004 3. Fang-I Lai, Y. S. Chang, T. H. Hseuh, H. C. Kuo and S. C. Wang, ”Improvement
of kink characteristics and high speed performance of implanted VCSELs with a top transparent overcoating” Materal Science& Engineering (B), 113(3), pp.
203-206, 2004
4. H. C. Kuo, Y. S. Chang, C. F. Lin, T. C. Lu, and S. C. Wang, “MOCVD growth of high-performance InGaAsP/InGaP strain-compensated VCSELs with 850 nm emission wavelength,“ J. of Crystal Growth, 261 (2-3) 355-358 JAN 19 2004 5. H. C. Kuo, Y. S. Chang, F. Y. Lai, Tao-Hung Hseuh, L. T. Chu, L. H. Lai, and S.
C. Wang, “High Speed Performance of 850 nm VCSEL silicon-implanted AlGaAs/GaAs vertical cavity emitting lasers,” Solid-State Electronics 48(3): Dec, 483-485 MAR 2004 (SCI)
6. Yi-An Chang, Hao-Chung Kuo, Ya-Hsien Chang, Shing-Chung Wang,
“ Simulation of 1300-nm In0.4Ga0.6As0.986N0.014/GaAs1-xNx quantum-well lasers with various GaAs1-xNx strain compensated barriers ”, Optics Communications 241() 195–202, (2004)
7. T. C. Lu, W. C. Hsu, Y. S. Chang, H. C. Kuo and S. C. Wang, “Measurement of Spontaneous Emission of oxide confined VCSEL,” Journal of Applied Physics, 96(11) 5992, 2004
8. Fang-I Lai, Tao-Hung Hsueh, Ya-Hsien Chang, Hao-Chung Kuo, S C Wang, Li-Hong Laih, C P Song, H P Yang, “10 Gb/s single-mode vertical-cavity
surface-emitting laser with large aperture and oxygen implantation,”
Semiconductor Science and Technology, 19(8): L86 2004 2003
1. H. C. Kuo, Y. S. Chang, F. Y. Lai, T. H. Hsueh, L. H. Laih, and S. C. Wang,
“High-speed modulation of 850 nm InGaAsP/InGaP strain-compensated VCSELs,” Electronics Letters, Vol. 39, No. 14, 1051-1053, July 2003
2. Fang-I Lai, Tao-Hung Hsueh, Ya-Hsien Chang, Wen-Chun Shu, Li-Hung Lai, H. C. Kuo and S. C. Wang, “Performance of 850 nm AlGaAs/GaAs implanted VCSEL utilizing Si implantation induced disordering,” Solid-State Electronics 47 (10): 1805-1809 OCT 2003
II. CONFERENCE PAPERS:
International:
2005
1. Y. H. Chang, G. R. Lin, H. C. Kuo, Jim Y. Chi, and S. C. Wang,“ Singlemode Monolithically Quantum-Dot Vertical-Cavity Surface-Emitting Laser in 1.3 µm with Side-mode Suppression ratio > 30dB”, IEEE/LEOS 2005 Annual Meeting 2. Hung-Pin D. Yang, Fang-I Lai, Ya-Hsien Chang, Hsin-Chieh Yu, Chia-Pin Sung,
Hao-Chung Kuo, S. C. Wang, Shih-Yen Lin, Jim Y. Chi,” Single Mode (SMSR>40dB) Proton-Implanted Photonic Crystal Vertical-Cavity Surface-Emitting Lasers”, Conference of Laser and Electro-Optics, CThW1
3. Hao-Chung Kuo, Yi-An Chang, Ya-Hsien Chang, Jung-Tang Chu, Min-Ying Tsai, and Shing-Chung Wang,” Single mode 1.27-µm InGaAs:Sb-GaAs-GaAsP Quantum Well Vertical Cavity Surface Emitting Lasers”, SPIE Photonic West, Conference 5364, paper 5737-22, Jan. 2005
4. Yi-An Chang, Hao-Chung Kuo, Ya-Hsien Chang, Shing-Chung Wang, and Li-Hong Laih, “Simulation and analysis of 1300-nm In0.4Ga0.6As0.986N0.014/GaAs1-xNx quantum-well lasers with various GaAs1-xNx
strain compensated barriers,” SPIE-Proceedings, vol. 5628, pp. 40-48, 2005.
(Invited) 2004
5. Y. H. Chang, H. C. Kuo, Y. A. Chang, M. Y. Tsai, S. C. Wang, N. Tansu, Jeng-Ya Yeh, Luke J. Mawst,” Temperature dependent photoluminescence of highly strained InGaAsN/GaAs Quantum Well (1280-1450 nm) with GaAsP strain-compensated layer”, International Conference on Solid State Devices and Materials, Tokyo, Japan (2004)
6. Y. H. Chang, H. C. Hsueh, F. I Lai, W. Y. Chang, C. C. Yu, W. H. Huang, C. F.
Lin, H. C. Kuo, S. C. Wang,” Observation of large spectral blue-shift in photoluminescence spectra of Mg-doped gallium nitride Nanorods”, International Conference on Solid State Devices and Materials, Tokyo, Japan (2004)
7. Ya-Hsien Chang , Hao-Chung Kuo , Fang-I Lai , Yi-A Chang , Po-Tsung Lee , Shing-Chung Wang,” Fabrication of high speed single mode 1.27 um InGaAs:Sb-GaAsP Quantum Wells Vertical Cavity Surface Emitting Laser”, International Conference on Solid State Devices and Materials, Tokyo, Japan (2004)
8. Y. S. Chang, H.C. Kuo, F. I. Lai, Y. A. Chang, L. H. Laih and S. C. Wang, ” Improvement of high speed performance for 10-Gb/s 850 nm VCSELs,” SPIE Photonic West, Conference 5364, paper 5364-10, Jan. 2004
9. T. H. Hsueh, Y. H. Chang, F. I Lai, H. W. Hung, M. C. Ou-yang, C. W. Chang, H.
C. Kuo, and S. C. Wang, “Fabrication and emission characteristic of InGaN/GaN multiple quantum wells nanorods,” CLEO 2004, IWA20.
10. H. C. Kuo, Y. S. Chang, F. Y. Lai, T. H. Hsueh, L. H. Lai, and S. C. Wang, “High speed Perfromance of 850 nm InGaAsP/InGaP strain-compensated VCSELs”, SPIE Proceeding 2004 (EI)
11. Tao-Hung Hsueh, Hung-Wen Huang, Chih-Chiang Kao, Ya-Hsien Chang, Miaochia Ou-Yang, Hao-Chung Kuo, Shing-Chung Wang,” InGaN/GaN Multi-Quantum-Well Nanorods Fabricated by Plasma Etching Using Self-assembled Nickel Nano-masks”, International Conference on Solid State Devices and Materials, Tokyo, Japan (2004)
2003
12. H. C. Kuo, Y. H. Chang, T. H. Hseuh, F. I Lai and S. C. Wang, “Development of 850nm VCSELs for OC-192 Application,” ECS conference2003. (invited) (EI) 13. H. C. Kuo, Y.S. Chang, T. H. Hsueh, C. C. Yu, J. W. Chang, C. F. Lin and S. C.
Wang, "Fabrication and Characterization of GaN Nanorods, " Electrochemical Soc.
Proc. Wide Bandgap Optoelectronic Materials and Devices (2003).
14. H. C. Kuo, T. C. Lu, Y. S. Chang, F. Y. Lai, G. C. Kao, L. H. Laih, and S. C. Wang,
“Growth and characterization of 850nm InGaAsP/InGaP strain-compensated VCSELs by MOCVD,” PR/CLEO 2003, paper W2B-(2)-7, December 2003
15. H. C. Kuo, W. C. Shu, T. C. Lu, Ya-Hsien Chang, Fang-i Lai, Li-Hung Lai, and S.
C. Wang, “Characterization of 850nm AlGaAs/GaAs implant vertical cavity emitting lasers utilizing silicon implantation induced disordering,” PR/CLEO 2003, paper THP-(2)-6, December 2003
16. Fang-I Lai, L. H. Laih, Y. S. Chang, T. H. Shei, H. C. Kuo, and S. C. Wang,
“Enhancement of proton-implanted GaAs VCSEL performance by transparent overcoating,” PR/ CLEO 2003, paper WP-(2)-9, December 2003
Domestic:
1. Y. H. Chang, C. C. Kao, T. H. Hsueh, T. C. Lu, H. C. Kuo, and S. C. Wang, “High speed modulation of InGaAsP/InGaP strain-compensated VCSELs,” Optics and Photonics Taiwan ’03, paper TB2-6, December 2003
2. Y. H. Chang, C. W. Chang, C. C. Yu, H. C. Kuo, and S. C. Wang, “Observation of enormous blue-shift in photoluminescence spectrum of Mg-doped GaN Nanorods,” Optics and Photonics Taiwan ’03, paper PA1-10, December 2003
3. J. Y. Lu, Y. H. Chang, F. Y. Lai, H. C. Kuo, and S. C. Wang, “Small signal modulation response of oxide-confined VCSEL with different aperture size,”
Optics and Photonics Taiwan ’03, paper FB4-2, December 2003
4. T. C. Lu, Y. H. Chang, C. W. Chang, W. C. Hsu, H. C. Kuo, and S. C. Wang,
“Spectrally resolved spontaneous emission patterns of oxide-confined vertical-cavity surface-emitting lasers,” Optics and Photonics Taiwan ’03, paper PA1-11, December 2003
5. C. L. Luo, G. F. Zeng, Y. H. Chang, F. Y. Lai, H. C. Kuo, and S. C. Wang,
“Simulation of multimode operation effects on modulation response of VCSEL,”
Optics and Photonics Taiwan ’03, paper FA2-6, December 2003
6. C. W. Chang, C. L. Lee, Y. H. Chang, M. C. O-Yang, H. C. Kuo, and S. C. Wang,
“Photoluminescence of gaN grown by HVPE with different V/III ratio,” Optics and Photonics Taiwan ’03, paper FA2-7, December 2003
7. F. Y. Lai, T. H. Hsueh, Y. H. Chang, W. C. Hsu, L. H. Lai, H. C. Kuo, and S. C.
Wang, “Performance of enhancement of AlGaAs/GaAs VCSEL utilizing silicon implantation induced disordering,” Optics and Photonics Taiwan ’03, paper FB3-1, December 2003
8. W. Y. Chen, F. Y. Lai, Y. H. Chang, L. H. Laih, H. C. Kuo, and S. C. Wang,
“Performance of GaAs VCSEL with a top transparent,” Optics and Photonics Taiwan ’03, paper FB3-8, December 2003
9. M. C. O-Yang, T. H. Hsueh, Y. H. Chang, C. W. Chang, H. C. Kuo, and S. C.
Wang, “Fabrication and optical characteristic of InGaN Multi-quantum well nanorods,” Optics and Photonics Taiwan ’03, paper FA3-3, December 2003