A comparison of free carrier absorption and capacitance voltage methods for interface trap measurements
2013 (English)In: Silicon Carbide and Related Materials 2012, Trans Tech Publications Inc., 2013, Vol. 740-742, 465-468 p.Conference paper (Refereed)
This paper aims to establish a new method to characterize the interface between 4H-SiC and passivating dielectric layers. The investigations are made on MOS test structures utilizing Al2O3 and SiO2 dielectrics on 4H-SiC. These devices are then exposed to various fluences of Ar+ implantation and then measured by the new method utilizing optical free carrier absorption (FCA) technique to assess the interface traps. A program has been developed using Matlab to extract surface recombination velocity (SRV) at the oxide/epi-layer interface from the optical data. Capacitance-voltage (CV) is done to extract the density of interface traps (Dit) and a comparison was made. It is observed that SiO2 samples show a large rise of SRVs, from 0.5×104 cm/s for a reference sample to 8×104 cm/s for a fluence of 1×1012 cm-2, whereas Al2O3 samples show more stable SRV, changing from 3×104 cm/s for the un-irradiated reference sample to 6×104 cm/s for a fluence of 1×1012 cm-2. A very similar trend is observed for Dit values extracted from CV measurements and it can therefore be concluded that the FCA method is a suitable technique for the interface characterization.
Place, publisher, year, edition, pages
Trans Tech Publications Inc., 2013. Vol. 740-742, 465-468 p.
, Materials Science Forum, ISSN 0255-5476 ; 740-742
4H-SiC, FCA, High-k dielectrics, Interface trap density, Radiation hardness, SRV
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-127228DOI: 10.4028/www.scientific.net/MSF.740-742.465ISI: 000319785500109ScopusID: 2-s2.0-84874098513ISBN: 978-303785624-6OAI: oai:DiVA.org:kth-127228DiVA: diva2:643978
9th European Conference on Silicon Carbide and Related Materials, ECSCRM 2012; St. Petersburg; Russian Federation; 2 September 2012 through 6 September 2012
QC 201308292013-08-292013-08-282014-06-16Bibliographically approved