Metalorganic Enhanced Ion Milling for BaSrTio3

The demand for higher performance semiconductor devices is pushing the limits of current materials technology. The development of a high dieletric constant capacitor material with 10 - 100 times the charge storage of SiO2 would allow a flat capacitor cell to be used in 256 Mb DRAMs, and simple stacked capacitors to be adopted for 1 and 4 Gb generations. IBM, TI and Micron have entered into an ARPA sponsored development agreement with ATM to develop chemical vapor deposition of BaSrTiO3 thin films for advanced DRAMs, but exploitation of this material requires new patterning technology, since conventional dry etching processes are ineffective. The Phase I effort will demonstrate the viability of novel metalorganic dry-etching chemistry for patterning Pt/BaSrTiO3/Pt capacitors. The work will be performed in a custom metalorganic-enhanced ion million (MEIM) system modified with ATM's Liquid Delivery System for controlled introduction of the metalorganic compounds. In Phase II the process will be optimized for 200 mm wafers and if successful this technology would fold-in to the ARPA Ultra-Dense capacitors DRAM consortium for fabrication of VLSI BaSrTiO3 test structures. Anticipated Benefits: The proposed research is a vital component needed to incorporate ferroelectric materials in integrated electronics. The program will result in development of the high-rate dry etching process needed to enable sub-micron etching of BaSrTiO3 and related materials in commercial advanced electronic devices.