新型炭材料（中英文）2025，Vol.40Issue(5)：1169-1183,15.DOI:10.1016/S1872-5805(25)60974-7
微波等离子体CVD生长的掺氮超纳米晶金刚石薄膜的结构与电学性能
Structural and electronic properties of nitrogen-doped ultrananocrys-talline diamond films grown by microwave plasma CVD
Venkateswara Rao Sodisetti 1Somnath Bhattacharyya2
作者信息
- 1. Nano-Scale Transport Physics Laboratory,School of Physics,University of the Witwatersrand,Johannesburg WITS 2050,South Africa
- 2. Nano-Scale Transport Physics Laboratory,School of Physics,University of the Witwatersrand,Johannesburg WITS 2050,South Africa||DSI-NRF Centre of Excellence in Strong Materials,School of Physics,University of the Witwatersrand,Johannesburg WITS 2050,South Africa
- 折叠
摘要
Abstract
Nitrogen doping in chemical vapor deposition-derived ultrananocrystalline diamond(UNCD)films in-creases the electronic conductivity,yet its microstructural effects on electron transport are insufficiently understood.We investigated the formation of nitrogen-induced diaph-ite structures(hybrid diamond-graphite phases)and their role in changing the conductivity.Nitrogen doping in a hy-drogen-rich plasma environment promotes the emergence of unique sp3-sp2 bonding interfaces,where diamond grains are covalently integrated with graphitic domains,facilitating a structure-driven electronic transition.High-resolution transmis-sion electron microscopy and selected area electron diffraction reveal five-fold,six-fold and twelve-fold symmetries,along with an atypical{200}crystallographic reflection,confirming diaphite formation in 5%and 10%N-doped UNCD films,while high-er doping levels(15%and 20%)result in extensive graphitization.Raman spectroscopy tracks the evolution of sp2 bonding with increasing nitrogen content,while atomic force microscopy and X-ray diffraction indicate a consistent diamond grain size of～8 nm.Cryogenic electronic transport measurements reveal a conductivity increase from 8.72 to 708 S/cm as the nitrogen dop-ing level increases from 5%to 20%,which is attributed to defect-mediated carrier transport and 3D weak localization.The res-ulting conductivity is three orders of magnitude higher than previously reported.These findings establish a direct correlation between diaphite structural polymorphism and tunable electronic properties in nitrogen-doped UNCD films,offering new ways for defect-engineering diamond-based electronic materials.关键词
化学气相沉积金刚石/氮掺杂/金刚石-石墨烯复合材料/三维弱局域化/金刚石电子学Key words
CVD diamond/Nitrogen doping/Diamond-graphene composite/3D Weak Localization/Diamond electronics引用本文复制引用
Venkateswara Rao Sodisetti,Somnath Bhattacharyya..微波等离子体CVD生长的掺氮超纳米晶金刚石薄膜的结构与电学性能[J].新型炭材料（中英文）,2025,40(5):1169-1183,15.
