Impact of Hydrogen Plasma on Electrical Properties and Deep Trap Spectra in Ga2O3 Polymorphs

Abstract

In this study, the results of hydrogen plasma treatments of β-Ga2O3, α-Ga2O3, κ-Ga2O3 and γ-Ga2O3 polymorphs are analyzed. For all polymorphs, the results strongly suggest an interplay between donor-like hydrogen configurations and acceptor complexes formed by hydrogen with gallium vacancies. A strong anisotropy of hydrogen plasma effects in the most thermodynamically stable β-Ga2O3 are explained by its low-symmetry monoclinic crystal structure. For the metastable, α-, κ- and γ-polymorphs, it is shown that the net result of hydrogenation is often a strong increase in the density of centers supplying electrons in the near-surface regions. These centers are responsible for prominent, persistent photocapacitance and photocurrent effects.

Proton damage effects in double polymorph γ/β-Ga2O3 diodes

“…The increase of the net donor concentration after the H plasma treatment has been shown recently to be a common feature of all polytypes of Ga 2 O 3 under certain treatment conditions and can be attributed to the processes common for all of them and possibly ascribable to the formation of Ga vacancy complexes with 4 H atoms. 20 The effect of Ga 2 O 3 interactions with various plasmas is in general an interesting and fruitful area of research in which intriguing and potentially useful phenomena, such as a giant increasing of the photosensitivity of Schottky diodes after the treatment in Ar plasma 21 or a marked increase of the N solubility and the formation of GaNO after the treatment in N plasma 22 have been recently reported.…”