I have done irradiation on SiC and noticed uniform tensile strain from XRD. How does this irradiation induced strain could influence Schottky junction properties? Thanks.
Thanks for your reply. Yes, it is true that there will be modifications in the interface as well as bulk after irradiation on the Schottky device. I have just irradiated the wafer not the Schottky device and I'm just curious to know about the strain effect on junction properties. I'm looking for any relevant models or journals which could account such behaviors.
Generally, The Schottky barrier in between a semiconductor and metal contact depends upon the work function (φm) of the metal and the electron affinity (χs) of the semiconductor . So any change in φm and/or χs will definitely affect the Schottky device properties. You have already clarified that the Schottky device was made after irradiating the SiC wafer and got some strain from from the XRD measurement. Dr. Matthieu Petit pointed out that there may be slide change in the band gap due to induced strain at the time of irradiation. I am also completely agreeing that the strain induced change in band gap will be very small (~meV). Therefore, it may not influence that much to the Schottky device. Rather I may suggest to measure the band gap of SiC before and after the irradiation process. For measurement of band gap, you can adopt the simple technique like UV-Visible spectroscopy. If there is any significant change in the band gap after irradiation, definitely it will reflect in the Schottky device.
we thank you for the infos. Some related refs[1-3] might be useful. The noise amplitude increases with the (e-beam irradiation) dose[1]. Also[2], the electrical resistance and the lattice strains increase upon (electron beam) irradiation[3].
1. Effect of high energy electron irradiation on low frequency noise in 4H-SiC Schottky diodes http://aip.scitation.org/doi/10.1063/1.4979411
2. Fundamentals of Silicon Carbide Technology: ... http://onlinelibrary.wiley.com/book/10.1002/9781118313534;jsessionid=B26AF880A823C203D9DE928E3EC8A692.f02t04
3. focus on Table2: ...the lattice strains ... : EFFECT OF 3.0 MEV ELECTRON IRRADIATION ON 4H-SIC WAFER PROPERTIES https://www.researchgate.net/publication/265553572_EFFECT_OF_30_MEV_ELECTRON_IRRADIATION_ON_4H-SIC_WAFER_PROPERTIES
Article EFFECT OF 3.0 MEV ELECTRON IRRADIATION ON 4H-SIC WAFER PROPERTIES