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Title: Epitaxial growth of β -Ga 2 O 3 by hot-wall MOCVD
The hot-wall metalorganic chemical vapor deposition (MOCVD) concept, previously shown to enable superior material quality and high performance devices based on wide bandgap semiconductors, such as Ga(Al)N and SiC, has been applied to the epitaxial growth of β-Ga 2 O 3 . Epitaxial β-Ga 2 O 3 layers at high growth rates (above 1 μm/h), at low reagent flows, and at reduced growth temperatures (740 °C) are demonstrated. A high crystalline quality epitaxial material on a c-plane sapphire substrate is attained as corroborated by a combination of x-ray diffraction, high-resolution scanning transmission electron microscopy, and spectroscopic ellipsometry measurements. The hot-wall MOCVD process is transferred to homoepitaxy, and single-crystalline homoepitaxial β-Ga 2 O 3 layers are demonstrated with a [Formula: see text]01 rocking curve width of 118 arc sec, which is comparable to those of the edge-defined film-fed grown ([Formula: see text]01) β-Ga 2 O 3 substrates, indicative of similar dislocation densities for epilayers and substrates. Hence, hot-wall MOCVD is proposed as a prospective growth method to be further explored for the fabrication of β-Ga 2 O 3 .
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AIP Advances
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National Science Foundation
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