Mechanistic Insights of Sn-Based Non-Chemically-Amplified Resists under EUV Irradiation

BELMONTE, GUILHERME K.; CENDRON, SUELEN W.; GURUPRASAD REDDY, PULIKANTI; MOURA, CLEVERSON A.S.; GHULAM MOINUDDIN, MOHAMAD; PETER, JEROME; SHARMA, SATINDER K.; LANDO, GABRIELA; PUIATTI, MARCELO; GONSALVES, KENNETH E.; WEIBEL, DANIEL E.

APPLIED SURFACE SCIENCE

ELSEVIER SCIENCE BV

Año: 2020 vol. 533

0169-4332

Formulating high sensitivity and resolution in Extreme Ultraviolet (EUV) resists is a serious concern regarding the adaptation of EUV lithography. The incorporation of a high optical density Sn compound in MAPDST-co-ADSM (4-(methacryloyloxy)phenyl) dimethylsulfoniumtrifluoromethane sulfonate-co-(acetyldibutylstannyl methacrylate), a non-CAR photoresist, exhibits lithography resolution for sub-15 nm node when patterned under e-beam and Helium ion irradiation. The synthesized resists were irradiated at 103.5 eV (∼ 92 eV) using monochromatic synchrotron radiation. After EUV irradiation and oxidation, the resists were investigated using XPS, NEXAFS and by theoretical calculations (FEFF9 modeling program). It was observed significant changes in the labile CF3SO3? moiety, but interestingly its total dissociation or desorption was not observed after long exposure times. Bonds rearrangements of, formation of SnO2 and new S□C/C-F functionalities after irradiation were detected. Tho