Uji Sifat Kristal dan Optik Film Tipis Barium Stronsium Titanat (Ba0,4Sr0.6TiO3) Didadah Cuprum (II) Asetat (Cu(CH3COO)2)

Abstract

Film tipis Ba0,4Sr0,6TiO3 dengan variasi konsentrasi pendadah tembaga asetat (0, 0,5, dan 1%) pada substrat Si tipe-p (1 0 0) sebanyak lima lapis menggunakan metode Chemical Solution Deposition (CSD) dengan teknik spin coating (3000 rpm, selama 60 detik) dengan konsentrasi 2M telah berhasil di sintesis. Proses annealing ditahan pada suhu 850 oC selama 8 jam dengan kelajuan peningkatan suhu sebesar 1,67 oC/menit. Uji sifat kristal menggunakan XRD dengan metode Cramer-Cohen menunjukkan struktur kristal tetap berbentuk tetragonal dengan nilai parameter kisi yang semakin menurun. Hasil uji sifat oftik menggunakan spektrofotometer UV-Vis pada metode Kubelka-Munk dengan relasi Tauc Plot menghasilkan energi bandgap yang semakin mengecil. Bandgap tersebut berturut-turut 2,30, 2,29, dan 2,26 eV. Sedangkan uji optik menggunakan FTIR dengan relasi Kramers-Kronig diperoleh penurunan bilangan gelombang pada mode vibrasi fonon optik longitudinal (LO), optik tranversal (TO), serta penurunan hasil perpotongan dielektrik real dan imajiner.

Thin films of Ba0,4Sr0,6TiO3 with varying concentrations of copper acetate dopant (0, 0.5, dan 1%) on p-type Si (1 0 0) substrates consisting of five layers were successfully synthesized using the Chemical Solution Deposition (CSD) method with spin coating technique (3000 rpm, for 60 seconds) with a concentration of 2M. The annealing process was held at a temperature of 850 oC for 8 hours with a temperature increase rate of 1,67 oC minute. Crystal property testing using XRD with the Cramer-Cohen method showed a tetragonal crystal structure remaining and resulted in decreasing lattice parameter values. Optical property testing using UV-Vis spectrophotometer with the Kubelka-Munk method and Tauc Plot relationship yielded a decreasing bandgap energy with increasing dopant concentration. The bandgap values were sequentially 2,30, 2,29, 2,26 eV. Meanwhile, optical testing using FTIR with the Kramers-Kronig relationship resulted in a decrease in wavenumber in longitudinal optical phonon (LO) vibration mode, transverse optical (TO), as well as a decrease in the real and imaginary dielectric constant intersection results.