English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We report an investigation of the bulk optical, bulk acoustic, and surfaceacoustic phonons in thin films of turbostratic boron nitride (t-BN) and cubicboron nitride (c-BN) grown on B-doped polycrystalline and single-crystallinediamond (001) and (111) substrates. The characteristics of different types ofphonons were determined using Raman and Brillouin-Mandelstam light scatteringspectroscopies. The atomic structure of the films was determined usinghigh-resolution transmission electron microscopy (HRTEM) and correlated withthe Raman and Brillouin-Mandelstam spectroscopy data. The HRTEM analysisrevealed that the cubic boron nitride thin films consisted of a mixture of c-BNand t-BN phases, with c-BN being the dominant phase. It was found that whilevisible Raman spectroscopy provided information for characterizing the t-BNphase, it faced challenges in differentiating the c-BN phase either due to thepresence of high-density defects or the overlapping of the Raman features withthose from the B-doped diamond substrates. In contrast, Brillouin-Mandelstamspectroscopy clearly distinguishes the bulk longitudinal and surface acousticphonons of the c-BN thin films grown on diamond substrates. Additionally, theangle-dependent surface Brillouin-Mandelstam scattering data show the peaksassociated with the Rayleigh surface acoustic waves, which have higher phasevelocities in c-BN films on diamond (111) substrates. These findings providevaluable insights into the phonon characteristics of the c-BN and diamondinterfaces and have important implications for the thermal management ofelectronic devices based on ultra-wide-band-gap materials.

Optical and Acoustic Phonons in Turbostratic and Cubic Boron Nitride Thin Films on Diamond Substrates