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Platinum thin film collectors were deposited onto p-type Si(100) planar and trench substrates by liquid-delivery metal±organ-ic (LD-MO) CVD using Pt(EtCp)Me 3 , Pt(C 2 H 5 C 5 H 4 )(CH 3 ) 3 , for microbatteries. The resistivity and root-mean-square (rms) roughness of Pt thin films with (111) preferred orientation increased with the increase of both deposition temperature and system pressure. The deposition of Pt thin films was controlled by a gas-phase mass-transfer mechanism and Pt thin films deposited at 350 C showed the lowest resistivity, rms roughness, and the highest step coverage, 57 %, in trench structure. The LiCoO 2 cathode films (step coverage = 51 %) deposited on the trench Pt collector showed an increase in discharge capacity of approximately two and half times that of the planar Pt collector. Platinum thin films deposited by LD-MOCVD have a possible application as collector materials for LiCoO 2 thin film cathodes.

The structural and electrochemical properties of LiCoO2 cathode films grown on Pt∕TiO2∕SiO2∕Si substrates at 500°C by liquid-delivery metalorganic chemical vapor deposition (LDMOCVD) were investigated as a function of Li∕Co mol ratio. The electrochemical properties such as initial discharge capacity and cyclic retention were improved through the study of Raman spectra of as-grown and annealed LiCoO2 films. The deposition temperature of 500°C was chosen to characterize the films because films grown at 500°C showed a typical high temperature hexagonal phase without Co3O4 impurities in the films. The optimum annealing condition of as-grown samples with Li∕Co=2.0 and 3.0 was at 700°C for 30min in an oxygen ambient. The highest initial discharge capacity and capacity retention were obtained in Li‖LiCoO2 cells grown with Li∕Co=3.0 and 2.0, respectively, and were approximately 38μAhcm−2μm and 77%, respectively. The compositional window for an optimum electrochemical property exists in the range of Li∕Co=2.0to3.0 in an as-grown temperature of 500°C and annealing temperature of 700°C for 30min in O2.

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