In this paper a novel modelling of electron scattering trajectories is presented. The scattering is discussed in terms of short and long range components and a comparison is made with the conventional approach considering forward and back-scattering. The usual analysis is shown to uncorrectly take as representative of short-range effects the forward scattering component, which instead contains, besides a high-density localized central term, a long-range tail spread out over larger distances. A different parametrization of the scattering is introduced and, in particular, a generalized n{long right leg} is defined in place of the usual backscattering coefficient. The behaviour of the scattering components is studied by Monte Carlo simulation in a freestanding PMMA resist layer, 1.5 μm thick. Further results are shown, relative to some cases of practical interest, by considering a quite general system for master-mask fabrication. The limits of the conventional approach are demonstrated.
Short-range and long-range scattering in electron beam lithography / Messina, G; Paoletti, A.; Santangelo, S.; Tucciarone, A.. - In: MICROELECTRONIC ENGINEERING. - ISSN 0167-9317. - 20:3(1993), pp. 241-253. [10.1016/0167-9317(93)90004-O]
Short-range and long-range scattering in electron beam lithography
MESSINA G;S. SANTANGELO;
1993-01-01
Abstract
In this paper a novel modelling of electron scattering trajectories is presented. The scattering is discussed in terms of short and long range components and a comparison is made with the conventional approach considering forward and back-scattering. The usual analysis is shown to uncorrectly take as representative of short-range effects the forward scattering component, which instead contains, besides a high-density localized central term, a long-range tail spread out over larger distances. A different parametrization of the scattering is introduced and, in particular, a generalized n{long right leg} is defined in place of the usual backscattering coefficient. The behaviour of the scattering components is studied by Monte Carlo simulation in a freestanding PMMA resist layer, 1.5 μm thick. Further results are shown, relative to some cases of practical interest, by considering a quite general system for master-mask fabrication. The limits of the conventional approach are demonstrated.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.