Zobrazeno 1 - 10
of 23
pro vyhledávání: '"L. Douglas Bell"'
Overview and Progress Toward High-Efficiency, Air Stable, Cs-Free III-Nitride Photocathode Detectors
Autor:
Emma Rocco, Jonathan Marini, Kasey Hogan, Vincent Meyers, Benjamin McEwen, L. Douglas Bell, F. Shahedipour-Sandvik
Publikováno v:
IEEE Photonics Journal, Vol 14, Iss 2, Pp 1-12 (2022)
We review the recent progress to achieve air stable III-nitride photocathodes for applications as photon detectors. High conductivity p-type films are critically important to realize high quantum efficiency (QE) photocathodes with effective negative
Externí odkaz:
https://doaj.org/article/5a7bc1fce6c440d5abeefd7ae3b7852f
Autor:
Preethi Padmanabhan, Bruce Hancock, Shouleh Nikzad, L. Douglas Bell, Kees Kroep, Edoardo Charbon
Publikováno v:
Sensors, Vol 18, Iss 2, p 449 (2018)
Gallium nitride (GaN) and its alloys are becoming preferred materials for ultraviolet (UV) detectors due to their wide bandgap and tailorable out-of-band cutoff from 3.4 eV to 6.2 eV. GaN based avalanche photodiodes (APDs) are particularly suitable f
Externí odkaz:
https://doaj.org/article/151d581b03d348348a497baf267e6fe0
Autor:
Shouleh Nikzad, Michael Hoenk, April D. Jewell, John J. Hennessy, Alexander G. Carver, Todd J. Jones, Timothy M. Goodsall, Erika T. Hamden, Puneet Suvarna, J. Bulmer, F. Shahedipour-Sandvik, Edoardo Charbon, Preethi Padmanabhan, Bruce Hancock, L. Douglas Bell
Publikováno v:
Sensors, Vol 16, Iss 6, p 927 (2016)
Ultraviolet (UV) studies in astronomy, cosmology, planetary studies, biological and medical applications often require precision detection of faint objects and in many cases require photon-counting detection. We present an overview of two approaches
Externí odkaz:
https://doaj.org/article/f7b1af26bc8745119832843467d039b2
Autor:
Vincent Meyers, Michael A. Reshchikov, Kasey Hogan, Fatemeh Shahedipour-Sandvik, Baishakhi Mazumder, Steven W. Novak, Sean Tozier, Benjamin McEwen, L. Douglas Bell, Isra Mahaboob, Emma Rocco, Olivia Licata
Publikováno v:
Scientific Reports, Vol 10, Iss 1, Pp 1-8 (2020)
Scientific Reports
Scientific Reports
We report on the enhanced incorporation efficiency of magnesium dopants into facets of hexagonal hillock structures in N-polar GaN, studied by comparative analysis of GaN:Mg films grown by MOCVD on high and low hillock density GaN template layers. To
Autor:
Michael E. Hoenk, D. G. Hitlin, Alexander G. Carver, Ahmed M. Morsy, April D. Jewell, Michelle L. Povinelli, L. Douglas Bell, Todd J. Jones, Shouleh Nikzad, John Hennessy, Mickel McClish
Ultraviolet detection is often required to be made in the presence of a strong background of solar radiation which needs to be suppressed, but materials limitations at these wavelengths can impact both filter and sensor performance. In this work, we
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::bde168ca9990b1a90878079e793adaa1
https://resolver.caltech.edu/CaltechAUTHORS:20180705-162233792
https://resolver.caltech.edu/CaltechAUTHORS:20180705-162233792
Autor:
Shouleh Nikzad, Preethi Padmanabhan, Kees Kroep, Edoardo Charbon, Bruce R. Hancock, L. Douglas Bell
Publikováno v:
Sensors (Basel, Switzerland)
Sensors, 18(2)
Sensors; Volume 18; Issue 2; Pages: 449
Sensors, Vol 18, Iss 2, p 449 (2018)
Sensors, 18(2)
Sensors; Volume 18; Issue 2; Pages: 449
Sensors, Vol 18, Iss 2, p 449 (2018)
Gallium nitride (GaN) and its alloys are becoming preferred materials for ultraviolet (UV) detectors due to their wide bandgap and tailorable out-of-band cutoff from 3.4 eV to 6.2 eV. GaN based avalanche photodiodes (APDs) are particularly suitable f
Autor:
L. Douglas Bell, F. Shadi Shahedipour-Sandvik, Jeffrey M. Leathersich, John Bulmer, Puneet Suvarna, Jonathan Marini, Shouleh Nikzad, John Hennessy, Isra Mahaboob
Publikováno v:
IEEE Photonics Technology Letters. 27:498-501
We report on the development of ion implantation-based contact-edge termination technique to improve the reliability and performance of p-i-n and p-i-n-i-n GaN ultraviolet avalanche photodiode structures. The GaN photodiode structures were grown on s
Autor:
L. Douglas Bell, Puneet Suvarna, Jonathan Marini, Jeffrey M. Leathersich, Fatemeh Shahedipour-Sandvik, Shouleh Nikzad, John Hennessy
Publikováno v:
MRS Proceedings. 1635:23-28
We have investigated surface modification methods for avalanche photodiodes using dielectrics deposited by atomic layer deposition (ALD). Arrays of mesa GaN APDs were fabricated, and ALD Al2O3 was used for sidewall passivation prior to completing the
Autor:
Shouleh Nikzad, Fatemeh Shahedipour-Sandvik, Pratik Agnihotri, Mihir Tungare, L. Douglas Bell, Jeffrey M. Leathersich, Puneet Suvarna
Publikováno v:
Journal of Electronic Materials. 42:854-858
GaN-based visible-blind and AlGaN-based solar-blind avalanche photodiodes (APDs) have been grown and fabricated on sapphire substrates. The GaN p-i-n APDs show low dark current with high gain. The AlGaN layers for the Al0.55Ga0.45N-based APDs are gro
Publikováno v:
Journal of Applied Physics. 92:261-267
Layered dielectric tunnel barriers are expected to greatly increase the program/erase speeds of nonvolatile floating gate memory devices and could allow both nanosecond program/erase times as well as archival data storage. We have correlated dielectr