Point-Arc Remote Plasma Chemical Vapor Deposition for High-Quality Single-Crystal Diamond Selective Growth

Selective growth techniques are believed to be the most effective approaches in the fabrication of diamond devices. Herein, the contamination from antenna and mask damage that causes poor performance in electronic applications is overcome with a high-quality diamond film on Ib (100) substrate, obtained by utilizing point-arc remote microwave plasma chemical vapor deposition (MPCVD). Scanning electron microscope (SEM) images and energy dispersive X-ray (EDX) mapping suggest that the diamond nucleation and selective growth occurred only in unmasked regions. Crystalline quality is evaluated by Raman spectra. Mo concentration from the antenna is detected with secondary ion mass spectroscopy (SIMS) at only a background level in the selectively grown diamond, indicating that the films are free of contaminant from the antenna, at three orders of magnitude lower than the impurity concentration in films selectively grown by typical hot filament CVD. Moreover, the moderate growth rate (approximately 50 nm h⁻¹) enables high reproducibility, which is of great importance for the precise control thickness of the selective growth layer, and thus the proposed method offers significant potential for the architecture modification of diamond devices.