报告题目：A novel method for the fabrication of an ultra-thin nitrogen delta doping layer at shallow depths in diamond

报告人：Prof. Alon Hoffman, Schulich faculty of Chemistry, Technion, Haifa, Israel.

报告时间：2023年7月26日 下午15:00

报告地点：高水平实验楼B座一楼报告厅

报告摘要：

The negatively charged nitrogen vacancy center (NVˉ) is considered as a promising candidate for nanoscale magnetic sensing applications. In this lecture I will present the proof of a concept of an innovative delta doping technique to fabricate an ensemble of NVˉ centers at shallow depths in single crystal (100) diamond. A nitrogen delta doped layer with a concentration of ~1.8x1020 cm-3 and a thickness of a few nanometers was produced using this method. Nitrogen delta doping was realized by producing a stable nitrogen terminated (N-terminated) diamond surface using plasma nitridation process and subsequently depositing a thin layer of diamond on the N-terminated diamond surface. The concentration of nitrogen on the N-terminated diamond surface and its stability upon exposure to chemical vapor deposition conditions are determined by X-ray photoelectron spectroscopy (XPS) analysis. Secondary ion mass spectroscopy (SIMS) profile exhibits a positive concentration gradient of 1.9 nm/decade and a negative gradient of 4.2 nm/decade with a full width at half maximum of 7.5 nm. The proposed method offers a finer control over the concentration as well as on the thickness of the delta doped layer than the currently used ion implantation and delta doping techniques.

报告人简介：

Dr. Alon Hoffman is a full professor at the Schulich faculty of Chemistry at the Technion and also holds the Joseph Szydlowsky Chair in Science.  He completed his D.Sc. in 1987 at the Technion investigating adsorption processes on single crystal metal alloy surfaces by electron spectroscopy.  After several post doc years in the USA and Australia, Dr. Hoffman joined the Schulich Faculty of Chemistry in 1992 as a senior lecturer where he become full professor in 2007.  During the 2012-2016 he was Dean of the Schulich Faculty of Chemistry and during the 2018-2020 period he was Deputy Senior Vice president of the Technion. His research effort spans from basic to fundamental research in surface science and thin films with more than 300 publications in referred scientific journals, several book chapters and review articles. During the last thirty-four years Prof Hoffman' research has been related to different aspects associated to the chemical, physical and electronic properties of diverse carbon surfaces such as graphite, diamond and amorphous carbon. In particular, he has investigated very extensively the interaction of hydrogen, oxygen, nitrogen and water with single and poly crystalline diamond surfaces by high resolution electron energy loss spectroscopy and various electron spectroscopic methods such as XPS, UPS and AES.  He has also investigated the different processes involved in the formation – nucleation and growth- of polycrystalline diamond films by chemical vapor deposition onto non-diamond substrates.  

化学化工学院（碳中和未来技术学院）

2023年7月24日