Influences of Process Temperature on a Phase of Ga₂O₃ Thin Films Grown by Atomic Layer Deposition on Sapphire

Abstract

Influences of process temperature on the phase of Ga 2 O 3 thin films grown by atomic layer deposition (ALD) on a sapphire substrate is investigated. Ga 2 O 3 thin films grown by ALD at a process temperature of 200 C showed an amorphous phase; however, crystalline α-Ga 2 O 3 film was deposited at the deposition temperatures from 225 to 250 C. Above a process temperature of 300 C, α and β phases coexist in the grown Ga 2 O 3 thin film. Interestingly, β-Ga 2 O 3 thin film was deposited on the sapphire by an increase of working pressure during Ga 2 O 3 ALD process at the process temperature of 300 C. The bandgap of β-Ga 2 O 3 thin film was as high as~5.2 eV. A metal-semiconductor-metal type photodetector using the β-Ga 2 O 3 thin film exhibited a fast response speed with a short rise time of 1.3 μs for the detection of deep ultraviolet wavelengths.

A convenient platform for real‐time non‐contact thermal measurement and processing

“…In its application, the usage of such instrument requires additional processing in form of data science, which is an activity of extracting information from a series of complex data to generate further insight 8–10 . In general, temperature determines the phase and shape of matters, 11–14 and also affects chemical reactions and dynamic properties 15–18 . Measured temperature data provide the insight and knowledge regarding the material, in terms of stability and photothermal capability, which leads to many possibilities of new findings and breakthrough 19–23 .…”