Siv color center concentration enhancement by rapid thermal annealing of Si-doped MPCVD diamonds

Diamond, as an ultra-wide bandgap semiconductor material, exhibits promising properties including strong mechanical stability, fast thermal conductivity, strong radiation resistance and broad-spectrum transmittance. Notably, deep-level defects within the diamond introduce defect-induced energy levels known as color centers. The fluorescence emission from color centers has strong monochromaticity, wavelength stability, and thermal stability, making them great potential for applications in quantum information processing, optical sensing, and biological labeling. Among these, the silicon-vacancy (Siv) color center, characterized by a zero-phonon-line at 738 nm, demonstrates a short excited-state lifetime (1 − 4 ns) and a narrow zero-phonon-line width (≈5 nm) at room temperature, underscoring its superior performance and potential applications. This study investigates the luminescence properties of Siv color centers in silicon-doped single-crystal diamond grown via the microwave plasma chemical vapor deposition (MPCVD) method. Measurements of fluorescence luminescence intensity of Siv color centers were conducted using PL, point-by-point scanning of specific areas to form a mapping image to determine the location of Siv color centers. A strong correlation is established between the distribution of Siv color centers and the surface structural defects existing in the diamond material. The results may support for subsequent research on diamond Siv color-centered single-photon devices such as single-photon detectors, single-photon avalanche diodes.