Fabrication of thin film LiCo0.5Ni0.5O2 cathode for Li rechargeable microbattery

초록

LiCo<inf>0.5</inf>Ni<inf>0.5</inf>O<inf>2</inf> thin film cathodes were fabricated by electron beam evaporation and postannealing in oxygen atmosphere. As-deposited film showed almost amorphous characteristics, but included some crystalline phases. Hexagonal phase of LiCo<inf>0.5</inf>Ni<inf>0.5</inf>O<inf>2</inf> was formed in the films annealed between 500 and 700°C. The crystallinity of the film was improved as the annealing temperature increased to 700°C. Open-circuit voltage (OCV) curves were measured. Especially, the film annealed at 700°C for 10 min showed a similar OCV curve to that of bulk powder cathode. It can be suggested that LiCo<inf>0.5</inf>Ni<inf>0.5</inf>O<inf>2</inf> thin film is suitable for the cathode of Li rechargeable microbattery.