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Abstrak :
Pengguna komunikasi memerlukan sistem komunikasi yang efektif digunakan kapanpun, dimanapun dan di semua media yang diinginkan. Sistem komunikasi tersebut lebih efektif dilakukan oleh jaringan tanpa kabel dengan memanfaatkan teknologi radio over fiber (ROF). Sistem jaringan ROF yang banyak digunakan adalah jaringan RF yang menggunakan serat optik mode tunggal. Untuk itu diperlukan divais laser semikonduktor yang mempunyai noise dan distorsi rendah pada frekuensi tinggi. Pada penelitian ini dilakukan studi mengenai teknologi informasi, ROF dan laser semikonduktor. Kemudian dirancang secara optimal laser yang sesuai aplikasi ROF yaitu laser Surface Emitting Distributed Feedback (SEDFB). Pemodelan dimulai dari pemilihan material yang sesuai dengan aplikasi yang diinginkan, penentuan indeks bias dan ketebalan dari setiap lapisan penyusunnya, sampai optimalisasi parameter-parameter kerjanya, seperti confinement factor ( ??), far field, dan arus ambang. Dibutuhkan optimalisasi tebal lapisan di daerah aktif dan lapisan separated confinement heterostructure (SCH) pada laser yang menyeluruh agar tidak menurunkan kinerja parameter lain. Dari hasil simulasi didapat struktur ridge SEDFB menghasilkan operasi single mode 1550 nm dengan optical confinement factor 0,186, sudut keluaran cahaya (far field divergence) 450, optical loss 0,003 cm-1, interval grating duty cycle antara 0,5-0,.6 dan loss permukaan 24 cm-1 dan efisiensi struktur yang menghasilkan single lobe sebesar 41,78%. ......Present consumers need reliable and cost effective communication system that can support anytime, anywhere, and anymedia they want. Communication system will be effective with wireless using radio over fiber (ROF) technology. Link ROF system is most common RF transmission uses single mode optic fiber. That purpose, it needs semiconductor laser device which low noise dan low distortion at high frequencies. This Research study information technology, ROF and semiconductor laser. Then, optimum laser design due to ROF application in surface emitting distributed feedback (SEDFB) laser. Start modeling from material selection due to application it want, determined refractive index and determined thin composition layer, also work parameter optimum is confinement factor ( ??), far field, dan threshold current. This structure need optimum layer thin in active region and separated confinement heterostructure (SCH) layer for other work parameter do not breakdown. The simulation yielded ridge SEDFB structure which optical confinement factor 0,186, far field divergence 450, optical loss 0,003 cm-1, grating duty cycle interval0,5-0,.6, surface loss 24 cm-1 dan output efisiency laser of single lobe 41,78%.

Abstrak :
ABSTRACT
A good justification for gallium nitride on silicon is a potential for optoelectronic integrated circuits, and its low cost has stimulated the growth of GaN on large size wafers. The application interest for GaN/Si is power electronics. This current work focuses on characterization optical, electro-optical, and microstructural and simulation design of GaN/Si channel waveguide. For the characterization of GaN microstructure, we use SEM, TEM, AFM, and XRD to observe layer thickness, material structure, material roughness, and crystalline quality of materials. Using the guided wave prism coupling technique, we have fully established the index dispersion and, thickness of GaN at room temperature, as well as its surface roughness based on AFM characterization. Futhermore, the thermal dependence of GaN at ordinary and extraordinary refractive indices are determined to be at 1.227 10-5/ K and 1.77 10-5/ K, respectively. The thermal dependence of GaN shows better value than GaAs at the wavelength range of 0.4 - 1.5 m. It has a slightly low-temperature dependence. Results demonstrate that excellent waveguide properties of GaN on silicon with an optical propagation loss of GaN/Si at 633 nm is 2.58 dB/cm, which is higher than the propagation loss of GaN/sapphire at around 1.34 dB/cm. The roughness of GaN/Sapphire and GaN/Si samples have been identified at the range 1.6 - 5.2 nm and 9.6 - 13 nm, respectively. The birefringence of GaN/Si is negative within the range of -0.16 x10-2 to -6.06x10-2. This negative value means that the polarization of the wave is parallel to the optical axis. Electrooptic constants r13 = 1.01 pm/V and r33 = 1.67 pm/V are higher than those obtained for III-V GaAs semiconductors. We compared the results on Si with those on sapphire. Based on a numerical simulation using OptiBPM, the design result has single mode output with 1 m thickness layer of SiO2 at the planar waveguide design, while the channel waveguide design has 1 m thickness layer of GaN. The simulated result that the maximum power output approximately 50- 58 at the plannar and rib waveguide design.

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ABSTRAK
A good justification for gallium nitride on silicon is a potential for optoelectronic integrated circuits, and its low cost has stimulated the growth of GaN on large size wafers. The application interest for GaN Si is power electronics. This current work focuses on characterization optical, electro optical, and microstructural and simulation design of GaN Si channel waveguide. For the characterization of GaN microstructure, we use SEM, TEM, AFM, and XRD to observe layer thickness, material structure, material roughness, and crystalline quality of materials. Using the guided wave prism coupling technique, we have fully established the index dispersion and, thickness of GaN at room temperature, as well as its surface roughness based on AFM characterization. Futhermore, the thermal dependence of GaN at ordinary and extraordinary refractive indices are determined to be at 1.227 10 5 K and 1.77 10 5 K, respectively. The thermal dependence of GaN shows better value than GaAs at the wavelength range of 0.4 1.5 m. It has a slightly low temperature dependence. Results demonstrate that excellent waveguide properties of GaN on silicon with an optical propagation loss of GaN Si at 633 nm is 2.58 dB cm, which is higher than the propagation loss of GaN sapphire at around 1.34 dB cm. The roughness of GaN Sapphire and GaN Si samples have been identified at the range 1.6 5.2 nm and 9.6 13 nm, respectively. The birefringence of GaN Si is negative within the range of 0.16 x10 2 to 6.06x10 2. This negative value means that the polarization of the wave is parallel to the optical axis. Electrooptic constants r13 1.01 pm V and r33 1.67 pm V are higher than those obtained for III V GaAs semiconductors. We compared the results on Si with those on sapphire. Based on a numerical simulation using OptiBPM, the design result has single mode output with 1 m thickness layer of SiO2 at the planar waveguide design, while the channel waveguide design has 1 m thickness layer of GaN. The simulated result that the maximum power output approximately 50 58 at the plannar and rib waveguide design.