Chemical Infiltration through Deep UV Photoresist

Still nowadays in integrated circuits manufacturing, few materials patterns are defined by a wet etch on patterned deep UV photoresist. From dies to dies generation, an optical performance improvement is required, hence an evolution with thinner and thinner positive resist. This makes these latter more sensitive to wet chemical etchant through the polymer, reducing their protection of the underneath material. Following characterizations enable a clear understanding of BHF (Buffered HF) benefits versus diluted HF during a gate oxide definition.

Comparison of Nanosized Pattern of Calixarene and ZEP520 Resists by Using Energy Deposition Distribution

We numerically modeled the process of exposure and development of the calixarene negative resist and ZEP520 positive resist in electron beam lithography (EBL) in order to understand the limitation of nanopatterning of these two resists and to improve the resolution of the patterning. From the calculation of energy deposition distribution (EDD) in resist at various beam diameters, it is obvious that the fine probe beam with a diameter of 2 nm and thin resist should be adopted for formation of very fine dots. The simulation of resist development profile indicates that a dot size of 2 nm with a pitch of 20 nm can even be obtained at a higher critical energy density by using calixarene resist, while it cannot form the small pattern by using the ZEP520 resist because of the capillary force.

Estimation of Nanometer-Sized EB Patterning Using Energy Deposition Distribution in Monte Carlo Simulation

We have studied on theoretical electron energy deposition in thin resist layer on Si substrate for electron beam lithography. We made Monte Carlo simulation to calculate the energy distribution and to consider formation of nanometer sized pattern regarding electron energy, resist thickness and resist type. The energy distribution in 100 nm-thick resist on Si substrate were calculated for small pattern. The calculations show that 4 nm-wide pattern will be formed when resist thickness is less than 30 nm. Furthermore, a negative resist is more suitable than positive resist by the estimation of a shape of the energy distribution.

Fabrication of Nanopit Array Using Electron Beam Lithography

This work reported the fabrication of nanopits array pattern using electron beam lithography (EBL). The effects of electron dosage on pattern shape were evaluated through EBL with a positive resist, Poly Methyl Meth Acrylate (PMMA), under acceleration voltages of 20 and 30 kV. Pattern of nanopits with 200 nm diameter have been created on PMMA to investigate the effect of various electron beam doses. The SEM images have shown effect of the voltage and dosage variation on them. In addition, Monte Carlo simulation has been done to show the scattering of electrons and proximity effect at different voltages in PMMA in order to explain the experimental results.