Surface zeta potential and diamond growth on gallium oxide single crystal

Abstract

In this work a strategy to grow diamond on $\beta$-Ga${}_2$O${}_3$ has been presented. The $\zeta$-potential of the $\beta$-Ga${}_2$O${}_3$ substrate was measured and it was found to be negative with an isoelectric point at pH $\sim$ 4.6. The substrates were seeded with mono-dispersed diamond solution for growth of diamond. The seeded substrates were etched when exposed to diamond growth plasma and globules of gallium could be seen on the surface. To overcome the problem $\sim$100 nm of SiO${}_2$ and Al${}_2$O${}_3$ were deposited using atomic layer deposition. The nanodiamond seeded SiO${}_2$ layer was effective in protecting the $\beta$-Ga${}_2$O${}_3$ substrate and thin diamond layers could be grown. In contrast Al${}_2$O${}_3$ layers were damaged when exposed to diamond growth plasma. The thin diamond layers were characterised with scanning electron microscopy and Raman spectroscopy. Raman spectroscopy revealed the diamond layer to be under compressive stress of 1.3 -- 2.8GPa.

References in corpus (6)

• Anisotropic Thermal Conductivity in Single Crystal beta-Gallium Oxide
• Raman tensor elements of $\beta {\text{-Ga}}_2{\text{O}}_3$
• Redox agent enhanced chemical mechanical polishing of thin film diamond
• Thermal stress modelling of diamond on GaN/III-Nitride membranes
• Surface zeta potential and diamond seeding on gallium nitride films
• Superconducting boron doped nanocrystalline diamond on boron nitride ceramics

Cited by in corpus (2)

• Microwave plasma modelling in clamshell chemical vapour deposition diamond reactors
• Electro-thermal Co-design of Vertical \b{eta}-Ga2O3 Schottky Diodes with High-permittivity BaTiO3 Field-plate for High-field and Thermal Management