High power and high capacity 3D-structured TiO2 electrodes for Lithium-Ion microbatteries

An on-chip compatible method to fabricate high energy density TiO2 thin film electrodes on 3D-structured silicon substrates was
demonstrated. 3D-structured electrodes are fabricated by combining reactive ion etching (RIE) with low pressure chemical vapor
deposition (LPCVD), enabling accurate control of the aspect ratio of substrates and the subsequent deposition of TiO2 thin film
electrodes onto these structured substrates. The prepared 3D-TiO2 electrodes exhibit a current-dependent increase in storage capacity
of a factor up to 16 as compared to conventional planar electrodes. In addition, these 3D electrodes also reveal excellent power
and cycling performance. This work demonstrates that LPCVD is capable of depositing homogeneous film electrodes on highly
structured substrates and the prepared 3D-electrodes also shows significant improve in storage capacity and power density.