CC BY 4.0Lebedev, VadimVadimLebedevKustermann, JanJanKustermannEngels, JanJanEngelsWeippert, JürgenJürgenWeippertCimalla, VolkerVolkerCimallaKnittel, PeterPeterKnittelKirste, LutzLutzKirsteGiese, ChristianChristianGieseQuellmalz, PatriciaPatriciaQuellmalzGraff, AndreasAndreasGraffJeske, JanJanJeske2024-04-232024-08-202024-04-232024https://publica.fraunhofer.de/handle/publica/466776https://doi.org/10.24406/h-46677610.1063/5.018963110.24406/h-466776Due to fascinating physical properties powered by remarkable progress in chemical vapor deposition of high-quality epilayers, diamond thin films attract great attention for fabrication of nitrogen-vacancy-based solid-state spin systems capable of operating in ambient conditions. To date, diamond heteroepitaxy via bias-enhanced nucleation is an unavoidable method for reliable wafer-scale film manufacturing. In this work, we analyze the coalescence phenomena in nitrogen doped, heteroepitaxial diamond epilayers, with a particular focus on their specific role in the annihilation of macroscopic crystal irregularities such as grain boundaries, non-oriented grains, and twinned segments. Here, we also report on the growth mechanism for the "primary" crystal orientation along with a predominant formation of two different types of boundaries highlighting the {011}-type as a main source of the crystal lattice irregularities.enjournal article