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oai:www.ideals.illinois.edu:2142/106487 2023-07-11 col_2142_5131 col_2142_8888 com_2142_5130 com_2142_8887 com_2142_234

Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2021-12-01 The student, Wonsik Choi, accepted the attached license on 2019-12-04 at 16:02. The student, Wonsik Choi, submitted this Dissertation for approval on 2019-12-04 at 16:32. This Dissertation was approved for publication on 2019-12-05 at 17:27. DSpace SAF Submission Ingestion Package generated from Vireo submission #14698 on 2020-02-28 at 17:37:56 Li, Xiuling Li, Xiuling Lyding, Joseph W Lee, Minjoo L Nam, Sungwoo Choi, Wonsik 2020-03-02T22:38:57Z 2020-03-02T22:38:57Z 2022-03-03T10:15:22Z 2019-12-05 2019-12 Bottom-up grown III-V compound semiconductor nanowires (NWs) provide a novel building block for electrical and optical devices. Bottom-up III-V NWs can be synthesized by either a vapor-liquid-solid (VLS) or selective area epitaxy (SAE) mechanism. Under the specific VLS NW growth conditions, planar self-aligned NWs can be grown on top of a substrate under a selective lateral epitaxy (SLE) mechanism. In this thesis research, first, the realization of lateral multiple p-n junction gallium arsenide (GaAs) SLE NW grown by metal-organic chemical vapor deposition (MOCVD) reactor is presented. Scanning microwave impedance microscopy (sMIM) and infrared scattering-type near-field optical microscopy (IR-SNOM) scans on top of the NW suggested that p-type zinc dopants are accumulated at twin-plane boundaries of NW. The electrical properties of the SLE GaAs lateral p-n junction were analyzed by measuring two-terminal I-V characteristics of arrays of p-n NW diodes. The I-V characteristics of the devices indicated that the lateral p-n junction was successfully realized with a high rectification ratio of ~106. The gallium phosphide (GaP) SAE NW growth on top of a silicon (Si) substrate will be also introduced. Systemic studies were performed by modulating the following three NW growth conditions: TMGa flow rate, growth temperature, and V/III ratio. By controlling the NW growth parameters, a 97.5% yield of hexagonal NWs was grown on an area of 400 µm × 400 µm. The morphology of the NWs was inspected with a scanning electron microscope (SEM). X-ray diffraction (XRD) analysis was performed on the GaP NWs, and 6.3016 Å of wurtzite (WZ) GaP c-lattice parameter was extracted. Vertical arrays of GaP p-n and p-i-n NW diodes were fabricated. The ideality factor and rectification ratio of p-n GaP NW diode were measured 7 and 10, respectively. The ideality factor and the rectification ratio could be improved to 3.7 and 1000 by introducing an undoped intrinsic layer between n-type and p-type GaP NW. Made available in DSpace on 2020-03-02T22:38:57Z (GMT). No. of bitstreams: 2 CHOI-DISSERTATION-2019.pdf: 3280922 bytes, checksum: c9f9f184126f776689131ca7fcac93a1 (MD5) LICENSE.txt: 4208 bytes, checksum: 00aae9612f680c13e3420a5fc4938848 (MD5) Previous issue date: 2019-12-05 Embargo set by: Seth Robbins for item 114031 Lift date: 2022-03-02T22:39:04Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Limited Restriction Lifted for Item 114031 on 2022-03-03T10:15:22Z. application/pdf http://hdl.handle.net/2142/106487 en "Chapter 2 was reproduced with the permission from [W. Choi et al., ""Direct electrical probing of periodic modulation of zinc-dopant distributions in planar gallium arsenide nanowires,"" ACS Nano, vol. 11, no. 2, pp. 1530-1539, 2017.] Copyright [2017] American Chemical Society." semiconductor nanowire selective lateral epitaxy selective area epitaxy sMIM IR-sSNOM Bottom-up growth of III-V compound semiconductor nanowires by selective lateral/area epitaxy text text Electrical & Computer Eng Electrical & Computer Engr University of Illinois at Urbana-Champaign Dissertation Ph.D.