| AVS 56th International Symposium & Exhibition | |
| Plasma Science and Technology | Tuesday Sessions |
| Session PS1-TuM |
| Session: | Advanced FEOL and BEOL Etch |
| Presenter: | H. Kintaka, TEL Technology Center, America, LLC USA |
| Authors: | H. Kintaka, TEL Technology Center, America, LLC USA T. Mori, TEL Technology Center, America, LLC USA M. Sasaki, Tokyo Electron Technology Development Institute, Inc. Japan T. Nozawa, Tokyo Electron Technology Development Institute, Inc. Japan |
| Correspondent: | Click to Email |
As the design rule of ULSI devices continue to be scaled down, the critical dimension (CD), CD bias, and the mask profile control technique has been needed. As the result of this study, precise CD control of multilayer mask etching was established by RLSA (Radial Line Slot Antenna) microwave plasma source. The multilayer stack which was used for experiments consisted of Photo Resist/SiARC/Organic/SiN/Si-substrate.
The results are: first, zero Iso/Nest bias was accomplished. As result, the same CD bias is obtained kept in both the Iso and Nest pattern with vertical profile. Second, CD Bias is controlled in the range of several +/- nm with same bias of Iso/Nest by adjusting SiARC etching condition. By these characteristics, it is possible to make hard mask CD same as patterned resist CD in any pattern density.
These results are obtained by RLSA micro-wave plasma characteristics. RLSA generates high density plasma just below top dielectric plate, and as the plasma diffuses forward the wafer, its density and electron temperature become lower by diffusion. The etched by-products do not re-dissociate and not deposit on the wafer in the low electron temperature condition. This result shows that this plasma can etch only biased ion direction without side-wall deposition.
These unique characteristic will remove the burden of adjusting the width in the patterning step.