Observation of Photoluminescence Characteristics of Diamond Color Centers of Polycrystalline Diamond Films Grown on Various Silicon Oxide Substrates by CVD Process
Srinivasu kunuku1*, Yen-Chun Chen2, Chien-Jui Yeh1, Wen-Hao Chang2, Keh-Chyang Leou1, I-Nan Lin3
1Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan
2Department of Electrophysics, National Chiao Tung University, Hsinchu, Taiwan
3Department of Physics, Tamkang University, Tamsui, Taiwan
* presenting author:Srinivasu Kunuku, email:space.309@gmail.com
Color centers are promising single photon sources for quantum computation, quantum information processing, bio marking and nano-magnetic sensor applications. Diamond have large number of color centers due to its wide band gap and among all the diamond color centers nitrogen vacancy (NV) and silicon vacancy centers are the prominent single photon sources, because of their stable emission at room temperature. However the NV center luminescence is strongly depends on the diamond crystal size, interaction with diamond lattice environment. SiV center exhibits better characteristics such as short lifetime, narrow zero phonon line width than NV center and these unique properties shows the new pathways to implement SiV center for practical applications. SiV center in diamond can be created ion implantation followed irradiation or intrinsic Si doping while diamond deposition in CVD process. According to previous reports, the Si implanted diamond samples were not shown the brighter SiV centers. By utilizing the CVD process, we can grow the brighter SiV and Si or SiO2 substrates act as the doping source. In the present work, we have demonstrated the growth of three kinds of morphological diamond films on Si and three varieties of SiO2 thin films. The photoluminescence (PL) properties were measured by using 532 nm excitation Nd:YAG laser to identify the signature of NV and SiV centers of all these diamond films. The diamond crystal size dependent PL properties of NV and SiV centers were observed. The diamond film’s microstructure has been examined using transmission electron microscopy to correlate with PL emission properties. It has been observed the high intense luminescence of both color centers and these properties can be tuned by the diamond growth process.

Keywords: color centers , single photon source, diamond, photoluminescence, transmission electron microscopy