AVS 66th International Symposium & Exhibition
    Plasma Science and Technology Division Tuesday Sessions
       Session PS-TuP

Paper PS-TuP16
Effect of Cx(x=4~7)F8 on the Etch Properties in Inductively Coupled Plasmas

Tuesday, October 22, 2019, 6:30 pm, Room Union Station B

Session: Plasma Science and Technology Poster Session
Presenter: Hyun Woo Tak, Sungkyunkwan University, Republic of Korea
Authors: H.W. Tak, Sungkyunkwan University, Republic of Korea
D.I. Sung, Sungkyunkwan University, Republic of Korea
Y.J. Shin, Sungkyunkwan University, Republic of Korea
D.W. Kim, Sungkyunkwan University, Republic of Korea
G.Y. Yeom, Sungkyunkwan University, Republic of Korea
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In semiconductor industries, the trend of scaling down is ongoing in ultra large scale integrated (ULSI) devices such as logic devices or 3D NAND devices. To achieve the scaling down of the devices, multiple patterning technologies such as double patterning technology (DPT) and quadruple patterning technology(QPT) have become essential technologies and require a high selective SiO2 etch process. In this study, three types of perfluorocarbon (PFC) precursors(C4F8, C5F8 and C7F8)were used and the effects of these PFCs on the etch characteristics of SiO2, Si3N4, and ACL and their etch selectivities were investigated by using Cx(x=4~7)F8/Ar/O2 plasmas. Among these, C5F8 and C7F8 are liquid phase at room temperature and, to deliver these liquid precursors to the process chamber,the inductively coupled plasma (ICP) system was equipped with a constant temperature heated canister and heated gas lines. The etch results showed that the selectivities of SiO2/Si3N4 and SiO2/ACL with C7F8/Ar/O2 plasmas were much higher than those with C4F8/Ar/O2 and C5F8/Ar/O2 at the optimized etch conditions. It is found that, with C7F8/Ar/O2 plasmas, lower F radicals in plasmas and thicker fluorocarbon polymers on material surfaces were formed. Furthermore, C7F8/Ar/O2 plasmas exhibited more anisotropic SiO2 etch profiles than the plasmas generated with C4F8/Ar/O2 and C5F8/Ar/O2.