α-(AlxGa1−x)2O3 single-layer and heterostructure buffers for the growth of conductive Sn-doped α-Ga2O3 thin films via mist chemical vapor deposition
| dc.contributor.author | Dang, Giang | |
| dc.contributor.author | Sato S | |
| dc.contributor.author | Tagashira Y | |
| dc.contributor.author | Yasuoka T | |
| dc.contributor.author | Liu L | |
| dc.contributor.author | Kawaharamura T | |
| dc.date.accessioned | 2023-11-20T21:25:38Z | |
| dc.date.available | 2023-11-20T21:25:38Z | |
| dc.date.issued | 2020 | |
| dc.description.abstract | A third generation mist chemical vapor deposition (3rd G mist CVD) system was used to grow six single-layer and two heterostructure α-(AlxGa1−x)2O3 buffers on c-plane sapphire substrates for the subsequent deposition of conductive Sn-doped α-Ga2O3 (Sn:α-Ga2O3) thin films. In the six single-layer buffers, the Al contents x increased from 0 to 0.66. The two heterostructure buffers consisted of six ∼20-nm- and ∼100-nm-thick layers laying on top of each other. The 3rd G mist CVD system enabled the growth of these complicated multi-layer heterostructures in a single run, while mono-crystallinity was still maintained in all grown layers. Strain was observed in the 20-nm heterostructure, while the layers in the 100-nm heterostructure almost fully relaxed and the Vegard’s law was followed even when the α-(AlxGa1−x)2O3 layers were stacked on each other. Transmission electron microscopy analyses show that the dislocation densities remained high in the order of 1010 cm−2 despite the employment of the buffers. PtOx and AgOx Schottky diodes (SDs) were fabricated on the Sn:α-Ga2O3 films. The barrier height vs ideality factor plots could be fitted by linear dependences, indicating that the large ideality factors observed in α-Ga2O3 SDs could be explained by the inhomogeneity of the SDs. The extrapolation of the dependences for the PtOx and AgOx SDs yielded homogeneous Schottky barrier heights of ∼1.60 eV and 1.62 eV, respectively, suggesting that the Fermi level was pinned at the Ec − 1.6 eV level. The Sn:α-Ga2O3 film grown on the strained 20-nm heterostructure buffer showed best characteristics overall. | |
| dc.identifier.citation | Dang GT, Sato S, Tagashira Y, Yasuoka T, Liu L, Kawaharamura T (2020). α-(AlxGa1−x)2O3 single-layer and heterostructure buffers for the growth of conductive Sn-doped α-Ga2O3 thin films via mist chemical vapor deposition. APL Materials. 8(10). | |
| dc.identifier.doi | http://doi.org/10.1063/5.0023041 | |
| dc.identifier.issn | 2166-532X | |
| dc.identifier.uri | https://hdl.handle.net/10092/106398 | |
| dc.language | en | |
| dc.publisher | AIP Publishing | |
| dc.rights | © 2020 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). | |
| dc.rights.uri | http://hdl.handle.net/10092/17651 | |
| dc.subject.anzsrc | 40 - Engineering::4016 - Materials engineering::401603 - Compound semiconductors | |
| dc.subject.anzsrc | 40 - Engineering::4016 - Materials engineering::401602 - Composite and hybrid materials | |
| dc.subject.anzsrc | 40 - Engineering::4008 - Electrical engineering::400802 - Electrical circuits and systems | |
| dc.subject.anzsrc | 34 - Chemical sciences::3403 - Macromolecular and materials chemistry::340309 - Theory and design of materials | |
| dc.subject.anzsrc | 34 - Chemical sciences::3402 - Inorganic chemistry::340202 - Crystallography | |
| dc.subject.anzsrc | 34 - Chemical sciences::3406 - Physical chemistry::340604 - Electrochemistry | |
| dc.title | α-(AlxGa1−x)2O3 single-layer and heterostructure buffers for the growth of conductive Sn-doped α-Ga2O3 thin films via mist chemical vapor deposition | |
| dc.type | Journal Article | |
| uc.college | Faculty of Engineering | |
| uc.department | Electrical and Computer Engineering |