Quaternary Ge-Sb-Se-Te chalcogenide thin films were fabricated by rf magnetron sputtering from Ge_(19)Sb_(17)Se_(64-x)Te_(x)(x=5,10,15,20)sputtering targets in order to select appropriate compositions for infrared sen...Quaternary Ge-Sb-Se-Te chalcogenide thin films were fabricated by rf magnetron sputtering from Ge_(19)Sb_(17)Se_(64-x)Te_(x)(x=5,10,15,20)sputtering targets in order to select appropriate compositions for infrared sensor and optical nonlinear applications.An influence of chemical composition and deposition parameters on the optical properties,structure and wettability was thus studied.The amorphous thin films seem to be constituted by selenide entities that can include tellurium atoms in variable proportion such as[GeSe_(4-x)Te_(x)]and[SbSe_(3-x)Te_(x)](x=0,1,2)and Ge(Sb)-Ge(Sb)bonds according to Raman spectroscopy.Contact angle measurements of the thin films showed values of 68e71for water and their surface energies in the range of~36e39 mJ$m-2 seem suitable for surface functionalization required for photonic sensor development.Furthermore,the maximum nonlinearity at the telecom wavelength with respect to the highest figure of merit value was found for the thin film with composition Ge_(19)Sb_(17)Se56Te8 having nonlinear refractive index of 28×10^(-18) m2·W^(-1).Due to their low optical bandgap energies,they may find their full interest for nonlinear optics in the mid-infrared range.Wide IR transparency in combination with high(non)linear refractive indices make these materials attractive in the field of midIR sensing and optical nonlinear devices.展开更多
基金This work was supported by the CNRS,Brittany region(France)ANR LOUISE(ANR-15-CE04-0001-01)+1 种基金ANR AQUAE(ANR-21-CE04-0011)Czech Science Foundation(Project No.19-24516S).
文摘Quaternary Ge-Sb-Se-Te chalcogenide thin films were fabricated by rf magnetron sputtering from Ge_(19)Sb_(17)Se_(64-x)Te_(x)(x=5,10,15,20)sputtering targets in order to select appropriate compositions for infrared sensor and optical nonlinear applications.An influence of chemical composition and deposition parameters on the optical properties,structure and wettability was thus studied.The amorphous thin films seem to be constituted by selenide entities that can include tellurium atoms in variable proportion such as[GeSe_(4-x)Te_(x)]and[SbSe_(3-x)Te_(x)](x=0,1,2)and Ge(Sb)-Ge(Sb)bonds according to Raman spectroscopy.Contact angle measurements of the thin films showed values of 68e71for water and their surface energies in the range of~36e39 mJ$m-2 seem suitable for surface functionalization required for photonic sensor development.Furthermore,the maximum nonlinearity at the telecom wavelength with respect to the highest figure of merit value was found for the thin film with composition Ge_(19)Sb_(17)Se56Te8 having nonlinear refractive index of 28×10^(-18) m2·W^(-1).Due to their low optical bandgap energies,they may find their full interest for nonlinear optics in the mid-infrared range.Wide IR transparency in combination with high(non)linear refractive indices make these materials attractive in the field of midIR sensing and optical nonlinear devices.
