Photon-induced Fragmentation of Zinc-based Oxoclusters for EUV Lithography Applications

Fluorine-Rich Zinc Oxoclusters as Extreme Ultraviolet Photoresists: Chemical Reactions and Lithography Performance

“…Mass spectrometry: the observed isotopic distribution corresponds to the presence of the tetranuclear Zn core of the oxocluster (Figure S4). The Zn oxocluster is susceptible to form complexes with acetonitrile (electrospray solvent), also observed in our previous studies. , The isotopic distribution observed in the mass spectra was assigned to the oxocluster complex: Zn 4 O with 5 TFMA ligands and 2 CH 3 CN molecules, which is in concordance with simulated spectra using ChemCal …”

UV and VUV-induced fragmentation of tin-oxo cage ions

“…[26][27][28][29] This method was very recently used for studies on organometallic molecular hybrid materials that can potentially be used as photoresists. 30,31 The tin-oxo cage dication can be isolated in the gas phase using a linear or quadrupole ion trap without any modification. 32,33 While irradiation of the doubly charged tin-oxo cage (dication) gives inside into its fundamental reactivity, studies on mono-cation complexes are also of interest.…”

Role of low-energy electrons in the solubility switch of Zn-based oxocluster photoresist for extreme ultraviolet lithography

“…In fact, previous studies on the photofragmentation of Zn(MA)(TFA) show that this oxocluster has a quite hygroscopic character since coordinated H 2 O molecules were observed when the clusters is brought to the gas phase. 34 …”

“… 41 We propose that a similar reactivity leads to the formation of CO as observed here. In fact, a previous study of photofragmentation pathways of Zn(MA)(TFA) in the gas phase 34 revealed that the loss of one ligand due to dissociative ionization led to products with m / z values that would be in agreement with loss of CO and one oxygen atom remaining in the cluster. However, these species overlap with products in which H 2 O molecules coordinate to the cation resulting after loss of a ligand.…”

“…In fact, previous studies on the photofragmentation of Zn(MA)(TFA) show that this oxocluster has a quite hygroscopic character since coordinated H 2 O molecules were observed when the clusters is brought to the gas phase. 34 The relative ESD yields of volatile species deriving from the 2-propenyl and CF 3 radicals as compared to CO 2 were estimated to support that the majority of the radicals released upon loss of CO 2 remains in the resist layer. Again, the details of this calculation are presented in the Supporting Information.…”