Translator Disclaimer
26 March 2008 Study of shallow trench isolation dry etching process using oxide hard mask and KrF photo-resist in 90 nm stand-alone flash device
Author Affiliations +
Abstract
We investigated that Shallow Trench Isolation (STI) dry etching process using SiO2 hard-mask and KrF photo-resist in 90nm stand-alone flash device. As shrinkage of design rule, the thickness of photo-resist is reduced because of guarantee for process margin in photolithographic process, but the etch process margin is smaller. For the reason, the hard-mask system for etch is needed. Generally, the STI dry etching process is composed of two or three steps, such as the ARC etch, the hard-mask etch, and the Si etch. In order to etch multi-stacked layer (ARC, Oxide hard-mask (SiO2), Si3N4 as CMP stopping layer, and Si), we have controlled the parameters of etching (plasma power, gas, and pressure). In the SiO2 hard-mask and Si3N4 layer etching process, we use a mixture chemistry of CF4, CHF3, O2, and Ar and get an optimized condition for the multi-layer system. The SiO2 layer is role of mask for Si layer because the selectivity between SiO2 and Si is superior to others. Finally, we get a good horizontal and vertical profile of STI by using a mixture chemistry of Cl2, HBr, and O2.
© (2008) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Eunsang Cho, Mingon Lee, Dongwon Shin, Sangil Hwang, Sangwook Ryu, and Kanghyun Lee "Study of shallow trench isolation dry etching process using oxide hard mask and KrF photo-resist in 90 nm stand-alone flash device", Proc. SPIE 6923, Advances in Resist Materials and Processing Technology XXV, 69233V (26 March 2008); https://doi.org/10.1117/12.773264
PROCEEDINGS
11 PAGES


SHARE
Advertisement
Advertisement
Back to Top