Gallium oxide (Ga2O3) is a highly promising ultrawide‐bandgap semiconductor for power electronics that emerged about a decade ago. Epitaxial growth Ga2O3at the small scale is demonstrated. In order to develop scalable manufacturing of high‐performance epitaxial structures, in‐depth understanding of the fundamental growth processes, control parameters, and mechanism is imperative. This review discusses the recent progress in epitaxial growth of β‐Ga2O3films and highlights challenges in obtaining high growth rate, low defects, and high carrier mobilities. Compared with the other epitaxy methods, metal–organic chemical vapor deposition (MOCVD) offers a wider growth window and precursor selection option, to minimize the tradeoff between crystal quality and growth rate. Growth rate is inversely proportional to temperature, within a certain temperature window, because of the unavoidable premature gas‐phase reactions and desorption of the highly volatile gallium suboxide (Ga2O) at elevated temperatures. Growth defects, background impurity incorporation, and carrier mobilities can be affected by the choice of MOCVD precursors, nucleation, and adsorption/desorption/diffusion of adatoms on substrate surfaces of different orientations, including the effect of growing on cleavage and noncleavage planes. This review summarizes the current status of the epitaxial growth of β‐Ga2O3and analyzes the major factors that enhance mobility and reduce background doping concentration. The insights gained help advance the manufacturability of device‐grade epitaxial thin films.
In situ growth of pyrochlore iridate thin films has been a long-standing challenge due to the low reactivity of Ir at low temperatures and the vaporization of volatile gas species such as IrO3(g) and IrO2(g) at high temperatures and high
- NSF-PAR ID:
- 10307550
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- npj Computational Materials
- Volume:
- 7
- Issue:
- 1
- ISSN:
- 2057-3960
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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