{"603401":{"#nid":"603401","#data":{"type":"event","title":"Ph.D. Dissertation Defense - Mi-Hee Ji","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003ETitle\u003C\/strong\u003E\u003Cem\u003E:\u0026nbsp; \u003C\/em\u003E\u003Cem\u003EGrowth, Fabrication, and Characterization of III-nitride Semiconductors for High Performance Ultraviolet Avalanche Photodiodes by Metalorganic Chemical Vapor Deposition\u003C\/em\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ECommittee:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. Russell Dupuis, ECE, Chair , Advisor\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. Shyh-Chiang Shen, ECE\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. Douglas Yoder, ECE\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. Rao Tummala, ECE\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. Jae-Hyun Ryou, ME\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EAbstract: \u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe objective of this research is to develop high-performance III-nitride-based ultraviolet (UV) avalanche photodiodes (APDs) with high optical gain using metalorganic chemical vapor deposition (MOCVD) system. However, the realization of high-performance UV-APDs has been hampered by high dislocation densities originating from heteroepitaxial layer grown on the lattice-mismatched substrates, resulting in higher dark current density, device size limitation, and device failure by microplasma formation as well as low yield and non-uniformity in an array format. To achieve high-performance UV-APDs and arrays, material growth on bulk GaN substrates with low dislocation density, sophisticated device fabrication process including low-damage etching and high-quality dielectric passivation, and new UV-APD structure by employing impact-ionization engineering were discussed in this research. The major aims of the research are as follows: 1) to improve characteristics of Al\u003Csub\u003E0.05\u003C\/sub\u003EGa\u003Csub\u003E0.95\u003C\/sub\u003EN\u0026nbsp;\u003Cem\u003Ep-i-n\u003C\/em\u003EUV-APDs 2) to demonstrate uniform and reliable GaN\u0026nbsp;\u003Cem\u003Ep-i-n\u003C\/em\u003E\u0026nbsp;UV-APD arrays with large detection area 3) to demonstrate GaN\u0026nbsp;\u003Cem\u003Ep-i-p-i-n\u003C\/em\u003E\u0026nbsp;separate absorption and multiplication (SAM) UV-APDs.\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Growth, Fabrication, and Characterization of III-nitride Semiconductors for High Performance Ultraviolet Avalanche Photodiodes by Metalorganic Chemical Vapor Deposition "}],"uid":"28475","created_gmt":"2018-03-06 21:50:33","changed_gmt":"2018-03-06 21:50:33","author":"Daniela Staiculescu","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2018-03-23T10:30:00-04:00","event_time_end":"2018-03-23T12:30:00-04:00","event_time_end_last":"2018-03-23T12:30:00-04:00","gmt_time_start":"2018-03-23 14:30:00","gmt_time_end":"2018-03-23 16:30:00","gmt_time_end_last":"2018-03-23 16:30:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"434381","name":"ECE Ph.D. Dissertation Defenses"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"},{"id":"1808","name":"graduate students"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}