In-situ measurement of outgassing generated from EUV resist including metal oxide nanoparticles during electron irradiation

In this study, we evaluated the outgassing generated from EUV resist which included metal oxide nanoparticles during electron irradiation. We prepared two types of samples including ZrO2 and TeO2, and a sample without including metal oxide, respectively. The outgassing species were measured from each sample during electron irradiation at the Eth exposure dose. The electron acceleration energy was 2 keV. In the outgassing measurement, we used original in-situ outgassing monitoring system in quadrupole mass spectrometry which we developed. From the results of mass spectrum, we observed CO2, H2O as typical mass peaks at each sample. And also we observed C4H4O2 and C4H6O2 peaks in spectrum of each sample. And these peaks are guessed 2(5H)-furanone and butyrolactone generated from base polymer. C6H6 peaks were observed in the mass spectrum of including ZrO2 and TeO2. We guessed that these peaks are from benzene generated from photo-acid generator (PAG). On the other hand, C6H6 peaks were not observed in the mass spectrum of without metal oxide. About this, we could not explain that mechanism by our knowledge of the present, but we can guess that metal oxide nanoparticles worked to generate benzene. About metal oxide peaks did not observe about mass spectrum of each sample. Each metal or metal oxide might not be evaporated during electron irradiation.

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