Tantalum oxide dielectrics processed with spark-plasma sintering
Tantal oksidni dielektrik, izdelan s tehniko sintranja v pulzirajočem obloku plazme

P. Ctibor, J. Sedláček, T. Hudec
2020 Materiali in Tehnologije  
Tantalum pentoxide (Ta2O5) was sintered with spark-plasma sintering (SPS) using a commercial powder with micometric particles composed of nanometric crystallites. The influence of the SPS process and subsequent annealing on the microstructure, phase composition and dielectric properties was studied. After the sintering, the product was oxygen deficient because of the low pressure in the sintering chamber. Evacuation was necessary for the process because of the carbon pistons and carbon die used
more » ... and carbon die used for the powder compaction. After the subsequent annealing in air, the white color of Ta2O5 was restored, being a proper indication of a re-oxidation. Dielectric properties were studied in a broad range of frequencies and temperatures. As-sintered and also annealed samples exhibited a high relative permittivity in a range of 61-68, a loss factor of about 0.001 and a resistivity in the order of 10 11 Wm. Tantalov pentoksid Ta2O5 so avtorji~lanka zgo{~evali s postopkom sintranja v pulzirajo~em obloku plazme (SPS). Pri tem so uporabili komercialni prah mikrometrske velikosti delcev, sestavljenih iz nanometri~nih kristal~kov. Avtorji so {tudirali vpliv SPS-procesa in nadaljnjega'arjenja na mikrostrukturo, fazno sestavo in dielektri~ne lastnosti. Po sintranju so imeli sintrani vzorci zmanj{ano vsebnost kisika zaradi nizkega tlaka v komori za sintranje. Evakuiranje je bilo potrebno, saj so bili za zgo{~evanje uporabljeni grafitni pesti~i oz. trni in orodje. Po naknadnem'arjenju na zraku se je povrnila Ta2O5 bela barva, kar je bil znak, da je pri{lo do ponovne oksidacije oz. reoksidacije. Avtorji so dielektri~ne lastnosti vzorcev {tudirali v {irokem razponu frekvenc in temperatur. Sintrani in prav tako'arjeni vzorci so imeli visoko relativno permitivnost, med 61 in 68, faktor izgub okoli 0,001 in upornost reda velikosti 10 11 Wm. Klju~ne besede: tantalov oksid, dielektrik, sintranje v pulzirajo~em obloku plazme
doi:10.17222/mit.2019.074 fatcat:g7xfscq76jfspaogyoto57eps4