Dr. Devendra K. Sadana Profile

Dr. Devendra K. Sadana

Retired

SPIE Involvement:

Author

Proceedings Article | 13 March 2015 Paper

Vertical thinking in blue light emitting diodes: GaN-on-graphene technology

C. Bayram, J. Kim, C.-W. Cheng, J. Ott, K. Reuter, S. Bedell, D. Sadana, H. Park, C. Dimitrakopoulos

Proceedings Volume 9364, 93641C (2015) https://doi.org/10.1117/12.2082897

KEYWORDS: Light emitting diodes, Gallium nitride, Graphene, Silicon carbide, Blue light emitting diodes, Visible radiation, Solid state lighting, Laser liftoff, Semiconductors, Chemical lasers

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Proceedings Article | 8 February 2015 Paper

Polarization-free GaN emitters in the ultraviolet and visible spectra via heterointegration on CMOS-compatible Si (100)

C. Bayram, J. Ott, K. Shiu, C. Cheng, Y. Zhu, J. Kim, D. Sadana, M. Razeghi

Proceedings Volume 9370, 93702F (2015) https://doi.org/10.1117/12.2082894

KEYWORDS: Gallium nitride, Silicon, Ultraviolet radiation, Light emitting diodes, Visible radiation, Luminescence, Crystals, Semiconductor lasers, Light sources and illumination, Polarization

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Proceedings Article | 4 June 2014 Paper

Advanced flexible electronics: challenges and opportunities

Stephen Bedell, Davood Shahrjerdi, Keith Fogel, Paul Lauro, Can Bayram, Bahman Hekmatshoar, Ning Li, John Ott, Devendra Sadana

Proceedings Volume 9083, 90831G (2014) https://doi.org/10.1117/12.2051716

KEYWORDS: Nickel, Silicon, Gallium nitride, Flexible circuits, Semiconducting wafers, Germanium, Image processing, Photovoltaics, Sapphire, Solid state lighting

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Proceedings Article | 18 March 2013 Paper

Engineering future light emitting diodes and photovoltaics with inexpensive materials: Integrating ZnO and Si into GaN-based devices

C. Bayram, K. T. Shiu, Y. Zhu, C. W. Cheng, D. Sadana, F. H. Teherani, D. Rogers, V. Sandana, P. Bove, Y. Zhang, S. Gautier, C.-Y. Cho, E. Cicek, Z. Vashaei, R. McClintock, M. Razeghi

Proceedings Volume 8626, 86260L (2013) https://doi.org/10.1117/12.2009999

KEYWORDS: Gallium nitride, Silicon, Zinc oxide, Light emitting diodes, Indium gallium nitride, Crystals, Photovoltaics, Sapphire, Indium, Metalorganic chemical vapor deposition

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Indium Gallium Nitride (InGaN) based PV have the best fit to the solar spectrum of any alloy system and emerging LED lighting based on InGaN technology and has the potential to reduce energy consumption by nearly one half while enabling significant carbon emission reduction. However, getting the maximum benefit from GaN diode -based PV and LEDs will require wide-scale adoption. A key bottleneck for this is the device cost, which is currently dominated by the substrate (i.e. sapphire) and the epitaxy (i.e. GaN). This work investigates two schemes for reducing such costs. First, we investigated the integration of Zinc Oxide (ZnO) in InGaN-based diodes. (Successful growth of GaN on ZnO template layers (on sapphire) was illustrated. These templates can then be used as sacrificial release layers for chemical lift-off. Such an approach provides an alternative to laser lift-off for the transfer of GaN to substrates with a superior cost-performance profile, plus an added advantage of reclaiming the expensive single-crystal sapphire. It was also illustrated that substitution of low temperature n-type ZnO for n-GaN layers can combat indium leakage from InGaN quantum well active layers in inverted p-n junction structures. The ZnO overlayers can also double as transparent contacts with a nanostructured surface which enhances light in/out coupling. Thus ZnO was confirmed to be an effective GaN substitute which offers added flexibility in device design and can be used in order to simultaneously reduce the epitaxial cost and boost the device performance. Second, we investigated the use of GaN templates on patterned Silicon (100) substrates for reduced substrate cost LED applications. Controlled local metal organic chemical vapor deposition epitaxy of cubic phase GaN with on-axis Si(100) substrates was illustrated. Scanning electron microscopy and transmission electron microscopy techniques were used to investigate uniformity and examine the defect structure in the GaN. Our results suggest that groove structures are very promising for controlled local epitaxy of cubic phase GaN. Overall, it is concluded that there are significant opportunities for cost reduction in novel hybrid diodes based on ZnO-InGaN-Si hybridization.

Proceedings Article | 4 February 2013 Paper

Gallium nitride on silicon for consumer and scalable photonics

C. Bayram, K. T. Shiu, Y. Zhu, C. W. Cheng, D. Sadana, Z. Vashaei, E. Cicek, R. McClintock, M. Razeghi

Proceedings Volume 8631, 863112 (2013) https://doi.org/10.1117/12.2008788

KEYWORDS: Gallium nitride, Silicon, Metalorganic chemical vapor deposition, Oxides, Epitaxy, Scanning electron microscopy, Silica, Crystals, Photonics, Aluminum nitride

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Proceedings Article | 21 January 2012 Paper

Reliable GaN-based resonant tunneling diodes with reproducible room-temperature negative differential resistance

C. Bayram, D. Sadana, Z. Vashaei, M. Razeghi

Proceedings Volume 8268, 826827 (2012) https://doi.org/10.1117/12.913740

KEYWORDS: Gallium nitride, Resistance, Terahertz radiation, Diodes, Aluminum, Reliability, Oscillators, Electronic components, Optoelectronic devices, Polarization

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