Ramón Collazo
University Faculty Scholar and Professor
- Email: rcollaz@ncsu.edu
- Office: Research Building I 219
- Website: https://mse.ncsu.edu/collazo
Ramón Collazo received his BS in Physics from the University of Puerto Rico, San Juan, and has been involved in the growth and characterization of wide bandgap semiconductor thin films, especially nitrides and diamond, for the past 11 years. He has been particularly involved in developing a process for controlling the polarity in III-nitrides to develop lateral polarity homojunction along with their application to the first lateral p/n junction. Additionally, he has been involved in the development of AlN bulk single crystal substrates, their surface preparation, and further epitaxial thin film deposition for optoelectronics and power device applications. He was awarded the Facundo Bueso Medal for Physics and has authored over 60 publications and given presentations at national and international conferences.
Collazo’s research interests include Optoelectronic/Power Materials and Devices; III-N Wide Bandgap Semiconductors; Polar Materials: Nitrides and Oxides; Optics: Materials Characterization and Nonlinear
Publications
- A pathway to strain-free AlGaN grown on native GaN substrates
- Carter, M., Almeter, J., Rathkanthiwar, S., Kirste, R., Mita, S., Collazo, R., & Sitar, Z. (2026, March 25), Journal of Applied Physics. https://doi.org/10.1063/5.0315248
- Elimination of wing tilt laterally overgrown GaN
- Almeter, J., Mita, S., Dycus, J. H., Collazo, R., Sitar, Z., & Kirste, R. (2026, January 5), Applied Physics Letters. https://doi.org/10.1063/5.0295076
- Enabling the growth of thick, relaxed AlGaN films on bulk GaN substrates
- Almeter, J., Wang, K., Kirste, R., Reddy, P., Mecouch, W., Mita, S., … Sitar, Z. (2026, February 24), Journal of Applied Physics. https://doi.org/10.1063/5.0295263
- High-current, high-voltage AlN p–n junction diodes enabled by compositional grading
- Quiñones, C. E., Reddy, P., Mita, S., Rathkanthiwar, S., Liu, C.-I., Khachariya, D., … Sitar, Z. (2026, January 12), Applied Physics Letters. https://doi.org/10.1063/5.0309581
- Hole transport analysis in N-polar p-GaN
- Kamiyama, M., Rathkanthiwar, S., Quiñones, C. E., Mita, S., Reddy, P., Kirste, R., … Sitar, Z. (2026, February 18), Journal of Applied Physics. https://doi.org/10.1063/5.0316562
- On germanium doping of gallium nitride: Ion implantation vs in-situ doping during growth
- Sierakowski, K., Konczewicz, L., Kirste, L., Kawka, K., Kempisty, P., Gołyga, K., … Boćkowski, M. (2026, February 19), Materials Science in Semiconductor Processing, Vol. 2. https://doi.org/10.1016/j.mssp.2026.110540
- AlGaN based UVC LEDs on AlN with reflective contacts
- Kirste, R., Loveless, J., Almeter, J., Moody, B., Reddy, P., Rathkanthiwar, S., … Sitar, Z. (2025, March 19). , (Vol. 3). Vol. 3. https://doi.org/10.1117/12.3042261
- Experimental Characterization of Impact Ionization and Projection of Critical Electric Fields in High‐Al Content AlGaN
- Zhu, Z., Reddy, P., Satapathy, Y., Cao, L., Xiong, J., Gutierrez, M., … Fay, P. (2025, June 24), Physica Status Solidi (a), Vol. 6. https://doi.org/10.1002/pssa.202500129
- Experimental Characterization of Impact Ionization and Projection of Critical Electric Fields in High‐Al Content AlGaN
- Zhu, Z., Reddy, P., Satapathy, Y., Cao, L., Xiong, J., Gutierrez, M., … Fay, P. (2025, December 1), Physica Status Solidi (a). https://doi.org/10.1002/pssa.70202
- Mg-annealed anode contacts to reduce the on-resistance of GaN pn diodes formed via Mg implantation and ultra-high pressure annealing
- Hasan, M. A., Alessi, M., Khachariya, D., Mecouch, W., Mita, S., Reddy, P., … Pavlidis, S. (2025, August 15), Applied Physics Express, Vol. 18. https://doi.org/10.35848/1882-0786/adfc26
