الفهرس 
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Abstract
Recently, there has been considerable interest in 3D thin film lithium ion batteries, not only
dueto its high performance rate but also for its higher energy density compared to its planar
equivalents. In this work, electrolytic manganese dioxide (EMD) was anodically deposited
ontoTiN and platinum-coated silicon substrates from a solution of 0.3 M MnS04 + 0.3 M
H2S04 targeting film thicknesses between 25 and 100 nm. Next to planar substrates, the EMD
wasconformally-deposited onto high aspect ratio silicon pillars; a 3D structure aiming to
increasethe electrode surface area. The structure and morphology of the deposited EMD films
were characterized and tied to the observed electrochemical performance. Deposition
et’ficiencies as large as 80% were achieved, as determined from RBS. Raman spectroscopy
showed that the crystallinty of EMD film increases by annealing. X-ray photoelectron
spectroscopy (XPS) showed the presence of Mn (ll) and Mn (Ill) in the annealed samples.
Thee1ectrochemical activity of the EMD films for lithium intercalation was investigated in
propylene carbonate solvent with IM LiCI04, using Li metal as counter and reference
electrodes. Reversible insertion and extraction of u’ was observed only after annealing to
removewater from the films. The Lithium ion reversible intercalation capacity was dependent
onthe deposition current density, and the annealing conditions used for EMD fabrication. The
EMD films showed promising r.r capacity of up to 80%, as compared to the theoretical
capacity,based on RBS data (one Li ion per Mn02 unit). Based on a surface area gain of 20
for the 3D pillar structures, a capacity of 0.6 mAhlcm2 (r-l Ah/cm’’) is expected for
conformally-coated 300 nm thick film.