5TH International Congress on Technology - Engineering & Science - Kuala Lumpur - Malaysia (2018-02-01)

Design Of Damage-free Oxide Etching Chamber For 450mm Process Technology

For the next generation process technologies on 450 mm wafers, not only global uniformity over large area but damage-free results in etching process is important. In this work, plasma is generated by Inductively Coupled Plasma and flow patterns of neutral gas and reactive ions and radicals in the chamber are calculated for uniformity improvement and optimization. Chamber diameter and chamber and baffle structure and position are also determined for best etch uniformity. For damage free etching chemistry, mixture ratio of H2, N2 and NF3 gases is investigated. As the simulation results, 3.9% uniformity with 9.2 nm/min etch rate could be obtained when the flow rates of gases are 75 sccm of H2, 480 sccm of N2 and 5 sccm of NF3. The optimum baffle distance between the lower baffle and wafer stage is 50.5mm.
Se Geun Park, Han-Bit Kim, Sang-Jong Park, Chang Won Lee