Study And Fabrication Of Mos Capacitor With Pecvd Sioxny.
(Albertin, Katia Franklin)
Study and fabrication of MOS capacitor with PECVD SiOxNy.In this work, MOS capacitors with different chemical compositionsilicon oxynitride insulating layer, deposited by PECVD technique atlow temperature were fabricated and characterized, in order to studyits dielectric and interface properties, seeking its aplication asinsulating layer in MOS and thin films devices. The MOS capacitors werefabricated onto p-silicion wafers previously cleaned by a standardprocess, followed by the insulating layer deposition, photolitography,metalization and sinterization. The SiOxNy insulating layer wasdeposited by the PECVD technique at 320ºC changing the precursor gasesflows to obtain films with different chemical compositions. The MOScapacitors were characterized by capacitance and current vs. voltagemeasurements, from where the interface state density (Dit), theeffective charge density (Nss), the dielectric constant (k) and thefilm electrical breakdown field (Ebd) were extracted. The resultsshowed a dielectric constant varying linearly as a function of thefilms nitrogen concentration, going from a value of 3.9, correspondingto stoichiometric silicon dioxide (SiO2) to a value of 7.2,corresponding to stoichiometric silicon nitride film (Si3N4). We alsoobserved that nitrogen is an efficient diffusion barrier againstcontaminants. However, a large dispersion, about two orders ofmagnitude, in the effective charge and in the interface state densitywas observed. On the other hand, controlling some variables so as tokeep the Nss value constant (~1012 cm-2) we observed a Dit variation asa function of the film nitrogen concentration, this variation is smallwhen compared with the observed dispersion of two orders of magnitude,thus attributed to external factors. The smallest obtained Dit was4.55.1010 eV-1.cm-2, which is unexpected for a PECVD film without anyanealing process and is better than the values reported in theliterature for dielectrics obtained at high temperatures techniques (asLPCVD ? 800ºC and thermal oxynitridation ? 1100ºC). Therefore, we canconclude that the PECVD technique is promising for obtaining lowtemperature dielectrics.
Resumos Relacionados
- The Art Of The Film
- Electrically Assisted Transdermal And Topical Drug Delivery
- Solar Storma Destroy Ozone
- Horizontal Diffusion, Vertical Diffusion, And Internal Pressure In State Environmental Policymaking,
- Horizontal Diffusion, Vertical Diffusion, And Internal Pressure In State Environmental Policymaking,
|
|
