Perchloromethyl Mercaptan, CCl₃SCl, Excited with Synchrotron Radiation in the Proximity of the Sulfur and Chlorine 2p Edges: Dissociative Photoionization of Highly Halogenated Species

Abstract

We have investigated the dissociative photoionization of shallow-core excited CCl3SCl by using multicoincidence time-of-flight mass spectrometry and synchrotron radiation in the S 2p and Cl 2p edges. The relative abundances of the ionic fragments and their kinetic energy release values were obtained from both PEPICO (photoelectron photoion coincidence) and PEPIPICO (photoelectron photoion photoion coincidence) spectra. The dynamic of the ionic fragmentation of S and Cl 2p excited CCl3SCl has been studied and compared with those of CCl4. Features determined in the present study seem to be relevant aspects for explaining the dissociation of highly chlorinated species under the action of VUV irradiation. The fragmentation pattern shows that chlorine ion (Cl+) is prominently formed upon both S and Cl 2p excitations.

EUV photofragmentation study of hybrid nonchemically amplified resists containing antimony as an absorption enhancer

“…2 showed an interesting structure: the signal at 166.4 eV can be assigned to electronic transitions involving the spin-orbit split of the S 2p excited species (2p 1/2 and 2p 3/2 levels) mainly due to the unoccupied p* antibonding orbitals. [32][33][34] A mixture of several transitions can be invoked in the signal that appeared at 168 eV: 2p 1=2 /p*; 2p 3=2 /s * CÀS ; 2p 1=2 /s * CÀS ; and S 2p / empty S 3d states 33,34 . Finally the signals at about 172 eV and 182 eV may also be assigned to higher energy transitions S 2p / empty S 3d and S 2p/p * S]O sulfonic acid functionalities.…”

Performance evaluation of nonchemically amplified negative tone photoresists for e-beam and EUV lithography

“…Comparison with previous results of gas phase SO 2 and polymer samples [23][24][25] allows interpretation of the signal A to electronic transitions involving the spin-orbit split of the 2p sulfur excited species (2p 1∕2 and 2p 3∕2 levels) mainly to the unoccupied π Ã antibonding orbitals. Signal B may correspond to the mixture of 2p 1∕2 → π Ã , 2p 3∕2 → σ ðC─SÞ , 2p 1∕2 → σ ðC─SÞ , and S 2p → empty S 3d transitions that cannot be resolved.…”

“…11) showed that signal B resisted the irradiation and signal C shifted to higher energies in ∼2 eV. The new signal of C ¼ 176.8 eV can be assigned to a transition from S 2p to the empty S 3d (t 2 states) and multiple high energy scattering, 24 i.e., losing the SO 3 functionality.…”

“…These materials show a very high etch resistance to the silicon substrate when compared to conventional organic resists. [22][23][24][25][26][27] The MAPDST-MMA copolymer was also tested under an etch recipe of CHF 3 ∕O 2 with a flow rate of 22.5∕2.5 sccm at a pressure of 80 mTorr with an RF power of 150 W for 1 min. In this case, the etch ratio for the MAPDST-MMA copolymer to the silicon dioxide was observed as 0.36∶1, which is also comparable to conventional organic resists under the same conditions.…”

Modeling unimolecular reactions in photoelectron photoion coincidence experiments

“…The combined photon–electron energy resolution of these experiments approaches and for one of these instruments has already gone beyond 1 meV (0.1 kJ mol −1 ). There are several other new PEPICO experiments with significantly lower resolution, namely a Finnish experiment at the Max III synchrotron facility in Sweden,39, 40 a PEPICO built for the Elettra synchrotron in Italy41 and one at the Laboratório Nacional de Luz Síncrotron (LNLS) in Brazil 42…”