AVS 62nd International Symposium & Exhibition
    Plasma Science and Technology Monday Sessions
       Session PS-MoM

Paper PS-MoM4
Trim Etch for sub-20 nm Technology

Monday, October 19, 2015, 9:20 am, Room 210B

Session: Advanced FEOL/Gate Etching
Presenter: Guangjun Yang, Micron Technology
Authors: GJ. Yang, Micron Technology
D. Keller, Micron Technology
Y. Rui, Micron Technology
R. Benson, Micron Technology
A. Schrinsky, Micron Technology
Correspondent: Click to Email
Photo resist trim with isotropic etch is a common practice in industry for CD control and line width roughness (LWR) improvement for sub 35 nm features imaged with 193nm lithography. As CD shrinks further, it becomes more challenging to control CD, to reduce line buckling or wiggling and to manipulate etch profile. For CDs below 20 nm, hardmask trim and live structure trim play an important role. In this talk, we will present a few examples of isotropic trim for sub-20 nm technology using mainly ICP chambers. In one case, DUV photo resist was trimmed from 40 nm to 15 nm with good LWR and good remaining height. In another case, a Si3N4/metal stack was trimmed down to 8 nm from 15 nm with good SWR (space width roughness) and etch profile. In the third case, we selectively trim DLC (diamond-like-carbon) in the bottom portion of the profile to make the etch profile straighter. Also we will discuss some challenges in developing a good isotropic trim process such as trim etch selectivity to materials and to location, etch uniformity. Finally we will discuss some opportunities for etch tool development.