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Surface Zeta Potential and Diamond Seeding on Gallium Nitride Films.

ABSTRACT: The measurement of ? potential of Ga-face and N-face gallium nitride has been carried out as a function of pH. Both of the faces show negative ? potential in the pH range 5.5-9. The Ga-face has an isoelectric point at pH 5.5. The N-face shows a more negative ? potential due to larger concentration of adsorbed oxygen. The ? potential data clearly showed that H-terminated diamond seed solution at pH 8 will be optimal for the self-assembly of a monolayer of diamond nanoparticles on the GaN surface. The subsequent growth of thin diamond films on GaN seeded with H-terminated diamond seeds produced fully coalesced films, confirming a seeding density in excess of 1011 cm-2. This technique removes the requirement for a low thermal conduction seeding layer like silicon nitride on GaN.

SUBMITTER: Mandal S

PROVIDER: S-EPMC6645065 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Surface Zeta Potential and Diamond Seeding on Gallium Nitride Films.

Mandal Soumen S Thomas Evan L H ELH Middleton Callum C Gines Laia L Griffiths James T JT Kappers Menno J MJ Oliver Rachel A RA Wallis David J DJ Goff Lucy E LE Lynch Stephen A SA Kuball Martin M Williams Oliver A OA

ACS omega 20171027 10

The measurement of ζ potential of Ga-face and N-face gallium nitride has been carried out as a function of pH. Both of the faces show negative ζ potential in the pH range 5.5-9. The Ga-face has an isoelectric point at pH 5.5. The N-face shows a more negative ζ potential due to larger concentration of adsorbed oxygen. The ζ potential data clearly showed that H-terminated diamond seed solution at pH 8 will be optimal for the self-assembly of a monolayer of diamond nanoparticles on the GaN surface. ...[more]

PMID: 31457302

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