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"Comprehensive in scope, this book covers the latest progresses of theories, technologies and applications of LEDs based on III-V semiconductor materials, such as basic material physics, key device issues (homoepitaxy and heteroepitaxy of the materials on different substrates, quantum efficiency and novel structures, and more), packaging, and system integration. The authors describe the latest developments of LEDs with spectra coverage from ultra-violet (UV) to the entire visible light wavelength. The major aspects of LEDs, such as material growth, chip structure, packaging, and reliability are covered, as well as emerging and novel applications beyond the general and conventional lightings. This book, written by leading authorities in the field, is indispensable reading for researchers and students working with semiconductors, optoelectronics, and optics.- Addresses novel LED applications such as LEDs for healthcare and wellbeing, horticulture, and animal breeding; - Editor and chapter authors are global leading experts from the scientific and industry communities, and their latest research findings and achievements are included;- Foreword by Hiroshi Amano, one of the 2014 winners of the Nobel Prize in Physics for his work on light-emitting diodes."

"Lapisan tipis ZnO telah ditumbuhkan di atas substrate silikon menggunakan teknik pengkabutan ultrasonik (USP) dengan variasi temperatur tumbuh. Analisis struktur menggunakan difraksi sinar-X menunjukan bahwa struktur dari lapisan tipis ZnO adalah polikristal. Berdasarkan analisis morfologi menggunakan scanning electron microscopy (SEM), ketebalan dari lapisan tipis tidak homogen. Berdasarkan analisis morfologi menggunakan atomic force microscopy (AFM), tingkat kekasaran (roughness) semakin berkurang ketika lapisan tipis dianil pada temperatur 800°C (tanpa anil 36.543 nm, setelah anil 24.754 nm). Sementara, berdasarkan pengukuran Hall, hambatan berkurang dengan penambahan temperatur tumbuh, mobilitas Hall bertambah dengan penambahan temperatur tumbuh, densitas pembawa muatan bernilai 1.18×1016 cm-3, 8.59×1015 cm-3, dan 9×1015 cm-3 ketika temperature tumbuh bertambah. Secara optik, spectrum photoluminisen menunjukan karakter spesifik dari ZnO, yaitu memiliki dua emisi ultraviolet (UV) dan cahaya tampak (hijau). Uji photoluminisen pada temperatur rendah untuk lapisan tipis ZnO tanpa anil, emisi UV dan cahaya tampak mengalami penambahan. Sedangkan untuk lapisan tipis ZnO dengan anil, puncak cahaya tampak mengalami penyusutan. Energi yang berasal dari defek teramati pada level 1.62 eV, 2.16 eV - 2.18 eV, dan 2.46 eV - 2.55eV. Energi defek pada level 1.62 eV berasal dari transisi elektronik dari bawah energi pita konduksi ke vakansi oksigen (Vo). Energi defek yang berada pada interval 2.16 eV - 2.18 eV berasal dari interstisial oksigen sedangkan energi defek pada rentang 2.46 eV - 2.55eV berasal dari transisi elektron dari vakansi oksigen yang terionisasi ke pita valensi. Selanjutnya, telah didemonstrasikan salah satu aplikasi pada bidang optoelektronika, yaitu pembuatan divais struktur hetero lampu dioda berbasis ZnO yang mampu menghasilkan warna akibat dari fenomena impact excitation.

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ZnO thin films have been deposited on top of Si substrate by ultrasonic spray pyrolisis (USP) at various growth temperatures. The structure analysis by X-ray diffraction shows that ZnO thin films has polycrystalline structure. The scanning electron microscopy (SEM) confirmed that the films thicknes are not homogenous. The atomic force microscopy (AFM) analysis shows the root means square (RMS) roughness of unannealed and atmosphere annealed (800°C) are 36.543 nm and 24.754 nm, respectively. According to Hall measurement, the resistivity of the films decreased with increasing temperatures. Hall mobilities increased when growth temperatures increased. The carrier density are 1.18×1016cm-3, 8.59×1015 cm-3, and 9×1015cm-3 when the temperatures 400°C, 450°C, and 500°C, respectively. Optically, the photoluminescence spectra shows typical of ZnO thin films which has two main peaks such as ultraviolet and green band.

The room temperature PL spectra show that the UV and green emission enhanced after annealing. At low PL spectra of annealed in atmosphere ambient, the green emission suppressed significantly. Some defect’s energy level were observed at 1.62 eV, 2.16 eV - 2.18 eV, and 2.46 eV - 2.55eV. The defect’s energy level 1.62 eV should be attributed to the electronic transition from the bottom of conduction band to the oxygen vacancy (Vo). The defect’s energy interval about 2.16 up to 2.18 eV originate from oxygen interstitial (Oi) and the defect's energy level about 2.5 eV (2.46 up to 2.55 eV) originate from the electron transition from the level of the ionized oxygen vacancies to the valence band. Finally, the device based ZnO heterostructure light emitting diodes (LEDs) have been demonstrated. It’s able to emit multicolour due to impact excitation."

"The development of nitride-based light-emitting diodes (LEDs) has led to advancements in high-brightness LED technology for solid-state lighting, handheld electronics, and advanced bioengineering applications. Nitride Semiconductor Light-Emitting Diodes (LEDs) reviews the fabrication, performance, and applications of this technology that encompass the state-of-the-art material and device development, and practical nitride-based LED design considerations.Part one reviews the fabrication of nitride semiconductor LEDs. Chapters cover molecular beam epitaxy (MBE) growth of nitride semiconductors, modern metalorganic chemical vapor deposition (MOCVD) techniques and the growth of nitride-based materials, and gallium nitride (GaN)-on-sapphire and GaN-on-silicon technologies for LEDs. Nanostructured, non-polar and semi-polar nitride-based LEDs, as well as phosphor-coated nitride LEDs, are also discussed. Part two covers the performance of nitride LEDs, including photonic crystal LEDs, surface plasmon enhanced LEDs, color tuneable LEDs, and LEDs based on quantum wells and quantum dots. Further chapters discuss the development of LED encapsulation technology and the fundamental efficiency droop issues in gallium indium nitride (GaInN) LEDs. Finally, part three highlights applications of nitride LEDs, including liquid crystal display (LCD) backlighting, infrared emitters, and automotive lighting."

"Tujuan penelitian ini adalah untuk mengetahui pengaruh jarak sumber sinar Light Emitting Diode (LED) terhadap kekuatan tarik diametral resin komposit bulk-fill. Resin komposit bulk-fill Tetric® N-Ceram Bulk-Fill, shade IVA (setara dengan warna VITA A2-A3) dibuat menjadi 30 spesimen berbentuk silinder dengan ukuran tebal 3 mm dan diameter 6 mm. Spesimen dibagi menjadi 3 kelompok variasi jarak penyinaran, yaitu 0 mm, 3 mm dan 5 mm. Penyinaran menggunakan LED Light Curing Unit Bluephase® Style (Ivoclar-Vivadent, Liechtenstein) dengan durasi penyinaran selama 10 detik sesuai instruksi pabrik. Data dianalisis secara statistik menggunakan metode ANOVA satu arah. Hasil analisis tidak menunjukkan perbedaan bermakna (p>0,05) pada semua kelompok. Jarak sumber sinar LED ≤ 5 mm tidak memberikan pengaruh yang signifikan terhadap kekuatan tarik diametral resin komposit bulk-fill.

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This study aimed to evaluate the effect of LED light source distance on diametral tensile strength of bulk-fill composite restorative material. Bulk-fill composite Tetric® N-Ceram Bulk-Fill, shade IVA (equal to VITA shade A2-A3) was formed into 30 cylindrical specimens with 3 mm in thickness and 6 mm in diameter. Specimens were divided into 3 groups with various curing distance: 0 mm, 3 mm and 5 mm. All groups were polymerized by LED Light Curing Unit Bluephase® Style (Ivoclar-Vivadent, Liechtenstein) for 10 seconds based on manufacturer’s instruction. Data were statistically analyzed by one-way ANOVA The result showed insignificant differences in all groups (p>0,05). LED light source distance ≤ 5 mm was not significantly affected the diametral tensile strength of bulk-fill composite."

"Organic Light Emitting Diode (OLED) merupakan divais electroluminescence yang menggunakan bahan organik sebagai lapisan emisif. Lab Nano Device Universitas Indonesia sudah mengembangkan OLED yang difabrikasi kan menggunakan metode laminasi. OLED yang dikembangkan meliputi lapisan anoda (TC-07-S) yang ditumbuhkan pada permukaan substrat plastik laminasi dan lapisan emisif (PFO) yang ditumbuhkan pada permukaan kertas aluminium (Al). Selain itu, proses fabrikasi menggunakan kapton sebagai bahan dielektrik untuk menghindari terjadinya arus singkat. Pada skripsi, ini dilakukan analisis pengaruh struktur satu kapton dan dua kapton terhadap hasil pengamatan visual optis dan unjuk kerja elektris OLED. Berdasarkan hasil pengamatan visual optis dan pengujian elektris didapatkan OLED dengan struktur dua kapton memiliki karakteristik optis dan unjuk kerja elektris yang lebih baik dari OLED dengan struktur satu kapton. OLED dengan struktur dua kapton dapat menghasilkan cahaya di seluruh permukaan lapisan emisif, memiliki nilai arus dan kerapatan arus sebesar 1,2mA dan 1,2mA/cm2 pada tegangan 15V, nilai tegangan threshold sebesar 14,25V, dan tingkat keberhasilan fabrikasi sebesar 77%. OLED dengan struktur satu kapton menghasilkan cahaya di sebagian permukaan lapisan emisif, nilai arus dan kerapatan arus sebesar 101μA dan 307μA/cm2 pada tegangan 15V, nilai tegangan threshold sebesar 14,5V, dan tingkat keberhasilan fabrikasi sebesar 8%. Hal ini kemungkinan disebabkan perekatan yang lebih baik antara lapisan emisif (PFO) dan anoda (TC-07-S) karena tekanan yang merata pada struktur dua kapton.

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Organic light emitting diode, widely known as OLED, is an electroluminescence device that utilizes organic material as its emissive layer. The Nano Device Laboratory of the University of Indonesia has previously developed OLEDs that are fabricated using the lamination process. The fabricated OLED comprises anode layer (TC-07-S) that is grown on the surface of the laminated plastic substrate, as well as emissive layer (PFO) that is grown on the surface of aluminium foil (Al). In addition, a dielectric material, kapton, is utilized on the fabrication process to help preventing short circuit of the device. Taking this into account, an analysis of influence of one-kapton and two-kapton to OLED optical visual observation and electrical performance was carried out. Based on the result of optical visual observation and electrical testing, it was discovered that the optical characteristic and electrical performance of two-kaptop OLEDs are significantly superior than one-kapton OLED. Two-kapton OLED emits light on the entire surface of the emissive layer, has a current value and current density of 1.2mA and 1.2mA/cm2 at a voltage of 15V, a threshold voltage value of 14.25V, and a fabrication success rate of 77%. One-kapton OLED emits light partially on the surface of the emissive layer, has a current value and current density of 101μA and 307μA/cm2 at a voltage of 15V, a threshold voltage value of 14.5V, and a fabrication success rate of 8%. This is most likely due to better connectivity between the emissive layer (PFO) and anode (TC-07-S) caused by even pressure of the two-kapton OLEDs."

"Salah satu permasalahan utama saat dilakukan terapi intravena adalah cairan infus tidak boleh habis dan laju aliran tetesan cairan infus tetap stabil, maka diperlukan pengawasan (monitoring) terhadap aliran cairan infus secara kontinu. Namun demikian, keterbatasan jumlah perawat untuk terus melakukan kontrol terhadap pasien menjadi masalah yang kerap ditemui terutama di Rumah Sakit Umum di Indonesia. Smart Infusion adalah perangkat yang didesain untuk dapat melakukan deteksi, pengukuran, dan pengaturan kecepatan tetesan cairan infus dalam selang waktu tertentu. Perangkat ini memanfaatkan LED IR383 (λ = 940 nm, 150 mW) dan fotodioda NTE3033 sebagai detektor tetesan cairan infus, motor DC sebagai pengatur kecepatan, serta mikrokontroler ATmega16, yang terintegrasi langsung dengan perangkat komputer melalui antarmuka GUI. Pengujian perangkat Smart Infusion ini dilakukan dengan variasi densitas cairan Dextrose, variasi simpangan perangkat infus, dan variasi tingkat kecepatan tetesan. Tingkat kesalahan rata-rata perangkat ini yang hanya sebesar 2,0105% menjadikan perangkat ini layak untuk diuji coba lebih lanjut.

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The main problems while performing intravenous therapy are both infusion solution bag must not be empty and flow of infusion solution must be stable, therefore continuous monitoring of infusion solution flow rate is needed. However, limited amount of nurses to check on each patient becomes a major issue, apparently on public hospitals in Indonesia. "Smart Infusion" is a device designed to detect, measure, and adjust the amount of infusion solution droplets per 30 seconds. The device is an integration of LED IR383 (λ = 940 nm, 150 mW) and photodiode NTE3033 as optical detector, DC motor as speed adjustment, ATmega16 as the processor, and GUI interface which allows the device to connect directly to a personal computer. Experiment of "Smart Infusion" consists of varying density of Dextrose, deviation of infusion set, and speed of infusion solution droplets. Average error rate of 2.0105% allow this device to have further experiments before being implemented."

"Lampu Light Emitting Diode (LED) termasuk beban non-linear yang meng-injeksi distorsi harmonik pada sistem tenaga listrik. Penelitian ini disusun sebagai bentuk studi untuk mengetahui karakteristik harmonik lampu LED yang telah tersedia di pasaran. Studi tersebut dilakukan dengan melakukan pengukuran terhadap 9 buah sampel lampu LED dengan berbagai merk dan rating daya.Dari hasil pengukuran diketahui bahwa harmonik tegangan dan arus pada lampu LED adalah harmonik orde ganjil dengan nilai harmonik tegangan terbesar pada orde kelima dan nilai harmonik arus terbesar pada orde ketiga. Selain itu, masing-masing lampu LED memiliki bentuk gelombang terdistorsi yang berbeda satu sama lain.

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Light Emitting Diode (LED) lights including non-linear loads that produce harmonic distortion. This experiment held as a form of study to determine the characteristics of LED lamps that have been available in the market, especially on the characteristics of the harmonic distortion generated. The study is done by conducting measurement of the harmonic content of the various branded sample LED lamps with various power rating.

Based on the measurement, it is known that LED lamps have odd harmonic distortion. The biggest voltage harmonic measured is fifth harmonic and the biggest current harmonic measured is third harmonic."

"Perancangan dan fabrikasi Organic Light Emitting Diode (OLED) semakin berkembang pesat seiring dengan dibutuhkannya OLED yang mudah difabrikasi dan menghasilkan performa yang lebih baik. Pada skripsi ini telah dilakukan simulasi dan fabrikasi OLED menggunakan proses laminasi. Simulasi menggunakan software SimOLED 4.5 dengan dua jenis struktur ITO/PFO/Al dan ITO/PEDOT:PSS/Al. Sementara itu untuk fabrikasi telah dihasilkan empat divais dengan struktur ITO/PFO/Al dan ITO/PEDOT:PSS//PFO/Al. Selanjutnya dilakukan analisis mengenai pengaruh PEDOT:PSS dan pembersihan ITO menggunakan ultrasonic cleaning terhadap karakteristik I-V OLED.Hasil simulasi menunjukkan bahwa tidak ada perbedaan karakteristik terhadap variasi anoda yang dilakukan namun pada fabrikasi penambahan PEDOT:PSS pada struktur dan pembersihan ITO menggunakan ultrasonic cleaning dapat menurunkan tegangan threshold. Divais dengan struktur ITO/PEDOT:PSS/PFO/Al dengan dilakukan pembersihan ITO memiliki performa terbaik dengan tegangan threshold terendah sebesar 1,6 V.

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Design and fabrication of Organic Light Emitting Diode (OLED) is growing rapidly along with the need for a convenient OLED fabricated and produce better performance. In this thesis has been carried out simulation and fabrication of OLEDs using a lamination process. SimOLED 4.5 software simulation using the two types of structure ITO / PFO / Al and ITO / PEDOT: PSS / Al. Meanwhile for the fabrication has produced four devices with structure ITO / PFO / Al and ITO / PEDOT: PSS // PFO / Al. Further analysis on the effect of PEDOT: PSS and ITO cleaning using ultrasonic cleaning of the I-V characteristics of OLED.

The simulation results showed that no differences in the characteristics of the variety anode made yet on fabricating the addition of PEDOT: PSS on the structure and cleaning of ITO using ultrasonic cleaning can lower the threshold voltage. Devices with the structure of ITO / PEDOT: PSS / PFO / Al to do the cleaning ITO has the best performance with the lowest threshold voltage of 1.6 V."