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Fractals once again :)

posted Jun 26, 2017, 11:00 AM by Khaled salama   [ updated Nov 20, 2017, 1:56 AM ]
Fractal capacitors aren't just beautiful geometrical shapes, they have plenty of Electronic advantages. In this work with prof. Hussam Alshareef, we report the first ever fractal micro-supercapacitors with 32% enhancement in energy density compared to conventional interdigital structures. The origin of this improvement can be attributed to the increased number of electrical lines of force in the fractal electrodes, which is caused by several open-edge segments. This study shows that electrode fractal design is a viable strategy for improving the performance of integrated micro-supercapacitors that use thin-film electrodes at no extra processing or fabrication cost. This work is covered at nanowerk article: 

Fabricating high-performance microsupercapacitors using fractal electrode designs

More details can be checked at:
Mrinal K. Hota, Qiu Jiang, Yousof Mashraei, Khaled N. Salama, and Husam N. Alshareef, Fractal ElectrochemicalMicrosupercapacitors, Advanced  Electronic Materials, 2017 DOI: 10.1002/aelm.201700185

At KAUST we have demonstrated fractals in a variety of applications:
  1. Yousof Mashraei, Shilpa Sivashankar, Ulrich Buttner, Khaled Nabil Salama, Integration of Fractal Biosensor in a Digital Microfluidic Platform, IEEE sensors jounal,  Vol 16, no 24, pp 8775 - 8783, 2016 (10.1109/JSEN.2016.2578440) (invited as top paper from sensors 2015 conference)
  2. A. M. Elshurafa, A.G. Radwan, P. H. Ho, M. Ouda and K. N. Salama "Low Voltage Puzzle-Like Fractal  MEMS Variable Capacitors Suppressing Pull-in" IET micro and nano letters, vol. 7, no. 9, pp. 965-969, 2012. 
  3.  Amro Elshurafa and Khaled N Salama, "A Differential RF MEMS Interwoven Capacitor Immune to Residual Stress Warping," IET Micro and Nano letters, Volume 7, issue 7, pp 658-661, July 2012  (IEEE top 10 accessed article August 2012)
  4. Amro Elshurafa and Khaled N Salama, "Two-layer RF MEMS fractal capacitors in PolyMUMPS for S-band applications," IET Micro & Nano letters, vol 7, no 5, pp. 419-421, May 2012. (IEEE top 10 accessed article june 2012)
  5. Amro Elshuarafa, Ahamed G Radwan, Ahmed Emira and Khaled N Salama,"RF MEMS Fractal Capacitors with High Self Resonant Frequencies ", IEEE Journal of Microelectromechanical Systems (JMEMS), vol 21, no 1, 10-12, 2012 (top 10 accessed article march 2012)
  6. F. Ghaffar, M. Umair, K. N. Salama, A. Shamim “ 24GHz LTCC based fractal antenna array with integrated lens for SOP Design”, IEEE Antennas and Wireless Propagation letters (AWPL), Vol 10, pages 705-708, 2011.