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peer-reviewed Focused Ion Beam (FIB) lithography has significant advantages over the electron beam counterpart in terms of resist sensitivity, backscattering and proximity effects. Applying the Top Surface Imaging (TSI) principal to FIB lithography could further enhance its capability. In this paper we review different FIB lithography processes which utilise both wet and dry development. As of further development of this technology, we report a novel lithography process which combines focused Cia' ion beam (Cia' FIB) exposure, silylation and oxygen dry etching. The Negative Resist Image by D q Etching (NERIME) is a TSI scheme for DNQhovolak based ICS~SIS and can result in either positive or negative resist images depending on the extent of the ion beam exposure dose. The NERlMF process can resolve nanometer resist patterns as small as 30nm yet maintaining high aspect ratio of up to 15. The proposed lithography scheme could be utilised for advanced prototype IC's fabrication and critical CMOS lithography process steps.

peer-reviewed In this paper, liquid-phase silylation process for Top Surface Imaging Lithography systems incorporated e-beam exposure has been experimentally investigated using FT-IR spectroscopy, UV spectroscopy, SIM spectrometry and SEM cross-sectionals. The impact of different silylating agents on Shipley SPR505A resist system is presented for both the UV exposed and e-beam crosslinked regions of the resist. Results show that an e-beam dose of 50??C/cm2 at 30KeV is sufficient to crosslink the resist and prevent silylation. The silylation contrast using HMCTS was found to be the highest (11:1) in comparison with other two agents. It was found that the silicon incorporation in SPR505A resist follows Case II diffusion mechanisms.

peer-reviewed This paper describes the modelling and simulation of two resolution enhancement techniques in lithography ; 1) phase shift mask (PSM) technology and 2) top surface imaging (TSI) with silylation and dry development. The effect of the duty ratio on the image contrast is computed. Simulated one and two dimensional rim shifters and attenuated PSMs are presented. The effect of the aerial image on the silylation profile for the top imaging processes, DESIRE and PRIME, is also presented. The effect of the first etch step on the final resist profiles is examined. The partial pressure and the presence of magnetic fields are also presented.