Simulation of Fine Resist Profile Formation by Electron Beam Drawing and Development with Solubility Rate Based on Energy Deposition Distribution

Abstract

We proposed a model for calculating the resist profile in electron beam drawing. The model predicts the solubility rate on the basis of the energy deposition distribution (EDD) for the development of latent patterns in the resist. By unifying the exposure dose D (via experiments) and EDDs (via calculations), we roughly determined solubility rates for three-dimensional EDDs, and established the proposed model. The development simulation was achieved by the sequential calculation method for solubility rates based on EDD which was calculated by Monte Carlo simulation. By determining a suitable EDD region to achieve good patterning, we obtained a sharp nanodot pattern of the resist. This simulation results are in good agreement with the experimental results obtained using a combination of 2.3 wt % tetramethylammonium hydroxide (TMAH) and 4 wt % NaCl as the developer. The model was demonstrated to be useful for predicting resist profiles with different experimental solubility rates of developers.

Estimation of the Depletion Layer Thickness in Silicon Nanowire-Based Biosensors from Attomolar-Level Biomolecular Detection

“…To fabricate NWs with different widths, the structure of the NWs was designed in various width scales (from 4 to 10 nm) using a computer design software (VectorWorks). The fabricated widths of HSQ NWs depend on the design width and are determined by the beam spot size, beam focusing techniques, and exposure dosages. , Therefore, design widths and exposure dosages using good beam focusing techniques were controlled to form NWs with different widths. To transfer HSQ NW patterns into the top Si layer of the SOI wafer, ICP-RIE was performed via CF 4 plasma etching.…”

Estimation of HSQ Resist Profile by Using High Contrast Developement Model for High Resolution EB Lithography

“…Resist development was simulated using the local solubility rate v, which was determined by the exposure dosage D of experimental data [3]. Assuming that v is proportional to D, the following can be obtained:…”

“…3 (a). The chemical composition and density of HSQ resist are H 8 Si 8 O 12 and 1.3 g/cm 3 , respectively. A 12 nm-thick resist was coated on Si substrate.…”

“…However, in order to find optimal EDD region, at first we should determine the width of EDD region for different contrast developers. In previous research [3], we deduced relationship between EDD and D as follows:…”

“…In order to understand the effect of developer contrast on resolution, in this work, we calculate developed HSQ dot profiles with different contrast developers by our home-made development model [3]. In order to calculate resist profiles under various contrast developers, several calculations have to be conducted.…”