Enhanced tunable properties of Ba0.6Sr0.4TiO3 thin films grown on Pt∕Ti∕SiO2∕Si substrates using MgO buffer layers

Abstract

Ba 0.6 Sr 0.4 Ti O 3 (BST) thin films were prepared on MgO buffered Pt(111)∕Ti∕SiO2∕Si substrates by pulsed laser deposition. The crystallographic structure, interface characteristics, and dielectric properties of BST thin films are strongly dependent on MgO thickness. BST thin films exhibit (111) preferred orientation when MgO layer is thicker than 5nm. The MgO layer can mitigate the interdiffusion between BST and Pt, causing the dielectric loss and leakage current of BST thin films to decrease significantly. The dielectric loss, tunability, and the largest figure of merit of BST thin films on 10nm MgO achieve 0.009, 30%, and 33.4, respectively.

Effects of CeO2 buffer layer thickness on the orientation and dielectric properties of Ba(Zr0.20Ti0.80)O3 thin films

“…It is known that the microstructure in the vicinity of the film/electrode interface plays an important role in defining the leakage current in films [28]. As an excellent isolating material, the CeO 2 layer can suppress the interdiffusion between BZT and Pt, reduce the formation of oxygen vacancies in BZT thin films, and maintain the thermal and chemical stabilities of Pt electrode [29,30]. Thus, the leakage current density of BZT thin films can be significantly lowered by using CeO 2 buffer layer.…”

Effects of interface on the dielectric properties of Ba0.6Sr0.4TiO3 thin film capacitors

“…Accordingly, the interfacial layer should be further studied in order to achieve the applications of the BST thin film capacitors. Although, many works were done to investigate the influences of interfacial layer on the thin film deposition method, film thickness, annealing, buffer layer, micostructure, electrode deposition [15][16][17][18][19][20]. Unfortunately, the effects of interfacial layer on dielectric properties of BST thin films have less been reported.…”

Effects of HfO2 buffer layers on the dielectric property and leakage current of Ba0.6Sr0.4TiO3 thin films by pulsed laser deposition

“…Effective measures such as improving of processing condition [4−5] , acceptor doping [6] and insertion of buffer layer [7−8] have been taken to reduce the loss. For BST thin films prepared on Pt/Ti/SiO 2 /Si substrates, proper selection of hetero-buffer layer can suppress the oxygen vacancy accumulation at the BST/Pt interface [7] or interdiffusion between BST and Pt electrode [8] , and thus improve the dielectric property and lower the leakage current. As a high-k gate dielectric material with large energy gap, HfO 2 is one of the most promising substitutes of SiO 2 in semiconductor industry [9−10] .…”