Characterization of HfO films deposited on 4H-SiC by atomic layer deposition
2007 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 101, no 12, 124105- p.Article in journal (Refereed) Published
Hafnium oxide films with a measured relative dielectric constant of 15.4 were deposited at room temperature on Si and 4H-SiC substrates, as well as on 4H-SiC p-i-n diodes. An 8 nm thick SiO2 interfacial layer on SiC increased the breakdown field of the HfO2/SiO2 stack by 6%, while a 13 nm thick SiO2 layer reduced it by 35%. The evidence of different current conduction mechanisms in SiO2 is shown to be related to the oxide thickness. For the diodes, the breakdown voltage was extended by at least 20%, compared to nonpassivated devices. Annealing at 400 °C in a forming gas changed the crystallinity and increased the relative dielectric constant of the HfO2 layers. There is an indication of reaction between HfO2 and SiO2 in the stacked films after annealing.
Place, publisher, year, edition, pages
2007. Vol. 101, no 12, 124105- p.
kappa gate dielectrics, interfacial layer, hafnium oxide, thin-films, decomposition, reliability, precursor, stability, silicon, devices
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-6601DOI: 10.1063/1.2734956ISI: 000247625700109ScopusID: 2-s2.0-34547425844OAI: oai:DiVA.org:kth-6601DiVA: diva2:11354
QC 201009282006-12-122006-12-122010-09-28Bibliographically approved