리튬 란타늄 타이타네이트 박막 고체 전해질의 특성 분석

초록

Recently, LiPON(Lithium Phosphorous Oxynitride), amorphous compound, has been widely used as a solid electrolyte in the all solid-state thin film battery. Instead of this, LLT(Lithium Lanthanum-Titanates) thin film was studied in this work since its relatively high ionic- conductivity comparing with the LiPON. In this work, electrochemical and physical properties were examined to reveal the feasibility of LLT as a thin film electrolyte. A LLT thin film was grown by RF-magnetron sputtering and the effect of heat treatment was investigated in order to determine optimal fabrication processes. Heat treatment was conducted at 100℃ and 300℃ in the furnace(Neyo 2-160 series Ⅱ) with normal atmosphere. After heat treatment, the crystallinity was investigated by XRD(Rigaku X-ray -diffractometer). The stability of LLT thin film was examined by LSV(Linear Sweep Voltammetry) in the range of 1 ～ 5V and we found a decomposition phenomenon of LLT. The ionic conductivity of LLT thin film was measured by Impedance(Zahner, IM6) with a blocking electrode which has structures of Pt-LLT-Pt and Pt-LLT-Li.