Towards Flexible Self-powered Micro-scale Integrated Systems Jhonathan Prieto Rojas Today's information-centered world leads the ever-increasing consumer demand for more powerful, multifunctional portable devices. Additionally, recent developments on long-lasting energy sources and compliant, flexible systems, have introduced new required features to the portable devices industry. For example, wireless sensor networks are in urgent need of self-sustainable, easy-to-deploy, mobile platforms,

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... lessly interconnected and accessible through a cloud computing system. The objective of my doctoral work is to develop integration strategies to effectively fabricate mechanically flexible, energy-independent systems, which could empower sensor networks for a great variety of new exciting applications. The first module, flexible electronics, can be achieved through several techniques and materials. Our main focus is to bring mechanical flexibility to the state-of-the-art high performing silicon-based electronics, with billions of ultra-low power, nano-sized transistors. Therefore, we have developed a low-cost batch fabrication process to transform standard, rigid, mono-crystalline silicon (100) wafer with devices, into a thin (5-20 µm), mechanically flexible, optically semi-transparent silicon fabric. Recycling of the remaining wafer is possible, enabling generation of multiple fabrics to ensure lowcost and optimal utilization of the whole substrate. We have shown mono, amorphous and poly-crystalline silicon and silicon dioxide fabrics, featuring industry's most advanced high-κ/metal-gate based capacitors and transistors. ACKNOWLEDMENTS This work has been possible due to the unconditional support of many people who has been there for me in so many ways and to whom I will always feel grateful. First of all, I would like to extend my deepest gratitude to Dr. Muhammad Mustafa Hussain, who has been my mentor ever since I joined KAUST back in 2009. Among the many valuable lessons, he has taught me and demonstrated that through innovation and perseverance you can achieve your greatest goals, and not to content yourself with your first success but to always keep improving and set even higher goals. His mentorship will continue to guide my entire professional career. To my committee, Prof. Jürgen Kosel and Prof. Udo Schwingenschlogl, thank you for your valuable time. To Prof. John A. Rogers thank you for being the role model of many aspiring researchers like me to inspire and to motivate our research work. I am also very thankful for the support of all my friends in the Integrated Nanotechnology group, especially Galo and Justine, who worked hand in hand with me so many times. Heartfelt thanks also to the staff of the Advance Nanofabrication, Imaging and Characterization Facilities and the Water Desalination and Reuse Center at KAUST, especially Ahad, Basil and Faisal, thanks for making the working environment a much easygoing one. To my all my close friends at KAUST, thank you so much for becoming my family in foreign lands and always taking care of me. To mention some of them: Francy,