Deposition of Electrolyte and Cathode Thin Films by Magnetron Sputtering.

摘要

A variety of ceramic materials exhibit sufficiently high ionic and mixed ionic-electronic conductivities to make them useful as electrolytes and electrodes for batteries, sensors, fuel cells, electrochemical displays, and for other applications. The ability to fabricate these materials in thin-film form offers possibilities for the development of solid state, microsized electrochemical devices that could be incorporated into integrated circuits. An example of such a device is the thin-film, rechargeable lithium battery. This cell potentially could be fabricated directly onto an IC substrate to serve as a backup power source for a CMOS-SRAM memory. We have fabricated several of these thin-film cells using magnetron sputtering and electron beam evaporation to deposit the various layers. One of these cells produced a steady current of 1 micro A at 3.2 volts. The performance of such thin-film cells after many charge-discharge cycles and their long term quiescent stability depend on the properties of the cathode and electrolyte films, as well as the anode-electrolyte and cathode-electrolyte junctions. Depositing films which minimize the resistance to lithium ion transport through the cell is a major challenge in the development of practical microbattery. In this paper, we summarize some recent results on the deposition and properties of lithium-ion conducting xLi4SiO4:yLi3PO4 glass electrolyte and V2O5 cathode films. 12 refs., 6 figs.