臺灣博碩士論文加值系統

現今光電通訊所需的資料量以爆炸性方式在成長，科技上對於光電元件需求量以及品質日漸增加，然而波導在光電元件負責傳輸大資訊量的光通訊，低損耗波導及強電光轉換主動層波導製作重要因素。本工作中提出利用量子井混成方式來製作一個可光場及電流侷限性埋入式異質半導體波導。藉由無雜質缺位晶格擴散方式改變波導參雜濃度，主動層參雜濃度的改變影響了操作波長藍位移、能帶變寬變大進而產生折射率差增大形成波導結構，使光膜態埋入至材料裡頭降低傳輸損耗，主動層選擇InGaAsP/InGaAsP材料增加能帶偏移以提高電子侷限能力。
在晶圓表面濺鍍的二氧化矽做為介電質材料，並對二氧化矽定義條狀式蝕刻出目標波導區域，此材料在快速熱退火時候產生應力在晶圓表面，晶圓的 Ga 會擴散到二氧化矽而在材料留下空缺進而改善熱混合製程。透過偏壓相依穿透率量測不但可得知電壓與電場有二次函數關係驗證了量子侷限史塔克效應的存在還觀察到輸入在3伏特就能有20dB的吸收調變；此外波導主動層在熱擴散對照區域折射率差值具0.07，遠場模擬發散角和實際在五微米波導的遠場發散角量測上數值近似，佐證折射率差改善光膜態侷限的能力；而近場量測分別透過三、五及七微米波導所得近場膜態圖型亦可以佐證波導侷限能力；在電激發光頻譜檢測可發現波長峰值和光激發螢光頻譜值近似，證明了波導亦同具有電性侷限能力。

Due to the dramatic increase in the need of optical communications, it becomes more important on developing the core of photonics integration elements. Among the elements in photonic integration circuits, electro-absorption modulator (EAM) is one of the key elements. To get high performance of EAM, low-loss and high-electrical-and-optical conversion efficiency optical waveguide thus plays an essential part. In this paper, quantum well intermixing (QWI) based on InGaAsP/InGaAsP material is applied for fabricating the waveguide of EAM with the buried semiconductor heterostructure. QWI with Impurity free vacancy diffusion (IFVD) enhanced by depositing SiO2 is used for changing the bandgap of InGaAsP/InGaAsP quantum well toward the blue shift regime, reducing refractive index. Therefore, patterning SiO2 could define both electrical and optical confinement optical waveguide.
The SiO2 film is sputtered on top of the wafer as dielectric material and also the pattern area of optical waveguide. After rapid thermal annealing, the reaction of Ga atom with SiO2 will induce vacancy, improving the interdiffusion in atom of quantum well. By increasing bandgap in SiO2 region, the accompanied index change defines the optical waveguide area. Above 80nm wavelength shift between in and outside SiO2 region was observed, where the window of 3, 5, and 7μm were used for setting optical waveguide. Through bias-dependent transmission, quadratic relation indicates the quantum confined Stark effect (QCSE) in quantum will, which can be used for developing high efficiency EAM. Besides, the SiO2 patterned area with large blue shift induces as high as 0.07 of refractive index change, suitably defining optical waveguide. Higher than 20dB of modulation efficiency within 3V voltage bias was shown in the devices. And through the observations on near field and far field of 3, 5 and 7um waveguide, it shows that the waveguide indeed possesses good optical confinement.

論文審定書 ii
公開授權書 iii
摘要 iv
Abstract v
圖次 ix
第一章 諸論 1
1-1 前言 1
1-2研究動機(Motivation) 2
1-3主動波導(Active waveguide)設計 3
1-4量子井材料能隙工程 5
1-5先前工作 12
1-6主要工作 15
第二章 理論與程式模擬 17
2.1 量子井熱混合機制 (Quantum Well Intermixing QWI) 17
2.2 電致光吸收調變器(EAM) 20
2.2.1 光吸收定理 21
2.3 量子侷限史塔克效應（Q.C.S.E.） 24
2.4 運算量子井熱混合擴散 26
2.5 量子井熱混合擴散後對能隙變化 28
2.6 運算量子井波函數及基態 30
第三章 材料分析與模擬 33
3-1 先前工作 33
3-2 元件設計模擬 36
3-2-1 缺陷擴散長度(Vacancy diffusion length) 36
3-2-2 主動波導設計 38
第四章 元件製程 42
4.1 晶圓結構示意圖 42
4.2 退火熱混合製程 43
4-3元件製程 46
4-3-1 蒸鍍P型金屬與對準記號 46
4-3-2 P型反向式梁脊波導蝕刻 48
4-3-3 蒸鍍N型金屬 50
4-3-4 平坦化製程 52
4-3-5共平面電極 58
4-3-6半絕緣基板研磨 60
第五章 量測結果與討論 62
5.1 EAM元件電流對電壓分析 62
5.2 電激發光頻譜檢測 63
5.3 光電流頻譜以及偏壓相依穿率(Bias-dependent transmission) 65
5.4 吸收頻譜 67
5.5 傳輸損耗(Propagation loss) 69
5.6 近場場型分析 70
5.7 遠場場型分析 71
5-8 結果與討論 77
參考文獻 78

[1]Photonic Integrated Circuit (IC) & Quantum Computing Market (2012 – 2022): By Application (Optical Fiber Communication, Optical Fiber Sensors, Biomedical)； Components (Lasers, Attenuators)； Raw Materials (Silica on Silicon, Silicon on Insulator)
[2]University of Maryland - Baltimore, ENEE 244 DIGITAL LOGIC AND DESOGN, "Optical waveguides" by NAKAJIMA,K
[3]Narrow-band waveguide Bragg gratings on SOI wafers with CMOS-compatible fabrication process
[4]Electro-optic modulator with exceptional powersize performance enabled by transparent conducting electrodes
[5]R. JW, J. LA, S. EJ,’’ 40 Gbit/s photonic receivers integrating UTC photodiodes with high- and low-confinement SOAs using quantum well intermixing and MOCVD regrowth’’ ELECTRONICS LETTERS 3rd August 2006 Vol. 42 No. 16
[6]V. Hofsass, J. Kuhm, C. Kaden, ‘‘Optical integration of laterally modified multiple quantum well structures by implantation enhanced intermixing to realize gain coupled DFB lasers’’ Nuclear Instruments and Methods in Physics Research B 106 (1995) 471-476
[7]Daniel Hofstetter, Bernd Maisenholder, and Hans P. Zappe, ‘‘Quantum-Well Intermixing for Fabrication of Lasers and Photonic Integrated Circuits’’ IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 4, NO. 4, JULY/AUGUST 1998
[8] Prakash N. K Deenapanray, H. H. Tan, Michael I. Cohen, Keith Gaff, Mladen Petravic and C. Jagadish ‘‘Silane Flow Rate Dependence of SiOxCap Layer Induced Impurity‐Free Intermixing of GaAs/AlGaAs Quantum Wells’’ Journal of The Electrochemical Society, Electrochem. Soc.2000 volume 147
[9]D. L. Green, E. L. Hu, and N. G. Stoffel ‘‘Effect of superlattices on the low‐energy ion‐induced damage in GaAs/Al(Ga)As structures’’ J, Vac. Sci. Technol, B 12(6), Nov/Dec 199
[10]H. S. Diie and T. Mei, ”Plasma-Induced Quantum Well Intermixing for
Monolithic Photonic Integration,” IEEE Journal of Selected Topics in Quantum Electronics, Vol. 11, No. 2, March/April 2005.
[11]H. S. Djie, T. Mei, J. Arokiaraj, C. Sookdhis, S. F. Yu, L. K. Ang, and X. H.
Tang, ‘‘Experimental and Theoretical Analysis of Argon Plasma-Enhanced Quantum-Well Intermixing,” IEEE Journal of Quantum Electronics, Vol. 40, No. 2, February 2004.
[12]S. Charbonneau, E. S. Koteles, P. J. Poole, J. J. He, G. C. Aers, J. Haysom, M.
Buchanan, Y. Feng, A. Delage, F. Yang, M. Davies, R. D. Goldberg, P. G. Piva,
and I. V. Mitchell, ”Photonic Integrated Circuits Fabricated Using Ion
Implantation,” IEEE Journal of Selected Topics in Quantum Electronics, Vol. 4,
No. 4, July/August 1998.
[13]O. P. Kowalski, C. J. Hamilton, S. D. McDougall, J. H. Marsh, A. C. Bryce, “A
universal damage induced technique for quantum well intermixing,” Appl. Vol. 72, 5 Number /2 February 1998.
[14]J. E. Epler, F.A. Ponce, F.J. Endicott, and T.L. Paoli, “Layer disordering of
GaAs/AlGaAs superlattices by diffusion of laser-incorporated Si,” J. Appl. Phys.
64(7), 1 October 1988.
[15]E. H. Li, and B. L. Weiss, “Analytical Solution of the Subbands and Absorption
Coefficients of AlGaAs/GaAs Hyperbolic,” IEEE Journal of quantum electronic,
Vol. 29, No. 2. February 1993.
[16]H. Kroemer, “Quantum Mechanics: For Engineering, Materials Science and
Applied Physics, Prentice Hall, 1994.
[17]李政鍵 , Unsymmetry Spiked-Quantum Well Design and Electroabsorption
Modulators Based on the InAlAs/InGaAlAs Material System,2004.
[18]I. Gontijo, T. Krauss, J. H. Marsh, and R. M. De La Rue, “Postgrowth control of
GaAs/AlGaAs quantum well shapes by impurity-free vacancy diffusion,” IEEE
Journal of Quantum Electronic, vol. 30, May 1994.
[19]L.J. Guido, N. Holonyak, K. C. Hsieh, R. W. Kaliski, and W.E. Plano, “Effects of dielectric encapsulation and As overpressure on Al-Ga interdiffusion in AlGaAs/GaAs quantum well heterostructures,” Journal Appl. Phys. 61(4), 15 February 1987.
[20]O. BS, M. K, Street MW, ”Selective quantum-well intermixing in GaAs-AlGaAs
structures using impurity-free vacancy diffusion” IEEE Journal of quantum
electronic Vol. 33 , October 1997.
[21]S. SK, Y. DH, Y. KH, ” Area selectivity of InGaAsP-InP multiquantum-well
intermixing by impurity-free vacancy diffusion,” IEEE Journal of Selected Topics in Quantum Electronics Vol.4, July/August 1998.
[22]http://www.ioffe.ru/SVA/NSM/Semicond/GaInAsP/bandstr.html
[23]A.S.W.Lee,M. MacKenzie, D.A. Thompson, J. Bursik, B. J. Robinso n,
Appl. Phys. Let t . 78, 3199 (2001).
[24]Y. Sugawara and T. Miyamoto, ‘‘Laterally intermixed quantum structure for
carrier confinement in vertical-cavity surface-emitting lasers ’’ ELECTRONICS LETTERS 29th January 2009 Vol. 45 No. 3
[25]T. Wolf, C.‐L. Shieh, R. Engelmann, K. Alavi and J. Mantz ‘‘‘Lateral refractive index step in GaAs/AlGaAs multiple quantum well waveguides fabricated by impurity‐induced disordering’’ Appl. Phys. Lett. 55(14), 2 October 1989
[26]C.L. Walker,A.C. Bryce‘‘Utilizing buried heterostructure Laser high brightness’’ IEEE photonics Technology Letters,Vol,14,No,10,October 2002
[27]S. L. Chuang,“Physics of Optoelectronic Devices,＂John Wiley &Sons,Inc",1995.
[28]H. Peyre, F. Alsina, J. Camassel, J. Pascual, R. W. Glew” Thermal stability of
InGaAsAnGaAsP quantum wells”, J. Appl. Phys. 73 (6), 15 April 1993.
[29]D. M. Baney, P. Gallion “Theory and Measurement Techniques for the Noise
Figure of Optical Amplifiers,” Optical Fiber Technology, June 2000.
[30]D. A. B. Miller, D. S. Chemla, T. C. Damen, A. C. Gossard, W. Wiegmann, T.H. Wood, C. A. Burrus, “Band-Edge Electroabsorption in Quantum Well Structure: The Quantum-Confined Stark Effect,” Phys. Rev. Lett. 53, 2173,1984.
[31]Semiconductor Optical Modulators by Koichi Wakita,NTT Opto-Electronics Laboratories,1998
[32]W. Franz, Z. Naturforsch. Teil A 13, 484 (1958)； L. V. Keldysh, Zh. Eksp. Teor. Fiz. 34, 1138 (1958) [Sov. Phys. JETP 34, 788 (1958)].L. V. Keldysh, Zh. Eksp. Sov. Phys., Vol. JETP7, pp. 788, 1953.
[33]H. Kroemer, “Quantum Mechanics: For Engineering, Materials Science, and Applied Physics, ” Prentice Hall, 1994.
[34]Propagation Characteristics of Ultrahigh-Δ Optical Waveguide on Silicon-on-Insulator Substrate, Jpn. J. Appl. Phys. Vol. 40 (2001) pp. L383–L385 Part 2, No. 4B, 15 April 2001,2001 The Japan Society of Applied Physics
[35]G. L. Li, Student Member, IEEE,C. K. Sun, “Ultrahigh-Speed Traveling-Wave Electroabsorption Modulator—Design and Analysis” IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 47, NO. 7, JULY 1999