In:
ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2018-01, No. 23 ( 2018-04-13), p. 1420-1420
Kurzfassung:
Monoclinic β-Ga 2 O 3 has attracted significant attention as a high power electronics material based on its ultra-wide energy gap (4.9 eV), high theoretical critical field (8 MV/cm), as well as the commercially availability of inexpensive substrates grown from the melt. In order to achieve breakdown field consistent with the theoretical expectations, however, very high quality epitaxial films with very low doping and defect density will be required. Wong et al. have reported a β-Ga 2 O 3 MOSFET with carrier concentration below 4x10 14 cm -3 , which is the lowest reported value for epitaxial β-Ga 2 O 3 to date [1]. This talk will discuss the structural and electronic properties for thick homoepitaxial β-Ga 2 O 3 with doping as low as 8x10 12 cm -3 , corresponding to breakdown voltage in excess of 2.38 kV (3.18 MV/cm), measured without field termination for vertical measurements or edge effects correction in the case of lateral devices. Our results show that current β-Ga 2 O 3 halide vapor phase epitaxial technology can produce epilayers with breakdown field approaching the theoretical value of GaN. In addition, we will discuss the annealing of bulk and epitaxial β-Ga 2 O 3 films in O 2 atmosphere as a potential pathway to reduce carrier concentration and possibly improve the breakdown voltage of Ga 2 O 3 Schottky diodes. We show that annealing Ga 2 O 3 in O 2 will reduce N D -N A by about an order of magnitude, similar to earlier observations by Kuramata et al. [2]. Furthermore, we will present our approach for overcoming the polaron-induced suppression of room-temperature p-type conductivity in Ga 2 O 3 , causing holes to preferentially self-trap instead of being available as free carriers [3]. We show that natural p-type semiconducting oxides such as NiO can be integrated with β-Ga 2 O 3 to form a rectifying heterojunction as a fundamental building block for any viable Ga 2 O 3 power device. Finally, we will discuss the low thermal conductivity of Ga 2 O 3 and present our preliminary thermal management simulations and experimental results. [1] A. Kuramata, et al., Jpn. Jour. Appl. Phys. 55, 1202A2 (2016). [2] M.H. Wong, et al., Appl. Phys. Express 10, 041101 (2017). [3] J.B. Varley, et al., Phys. Rev. B 85, 081109(R) (2012).
Materialart:
Online-Ressource
ISSN:
2151-2043
DOI:
10.1149/MA2018-01/23/1420
Sprache:
Unbekannt
Verlag:
The Electrochemical Society
Publikationsdatum:
2018
ZDB Id:
2438749-6
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