Effects of photoresist polymer molecular weight on line-edge roughness and its metrology probed with Monte Carlo simulations
A fast 2D/3D resist dissolution algorithm based on the critical ionization model is used to quantify line-edge roughness and determine its relation to resist polymer molecular weight, the end-to-end distance and the radius of gyration, keeping acid effects off (i.e., minimal). The algorithm permits also simulations of line-edge roughness metrology by examining the effects of SEM measurement box length.
mpact of photoresist composition and polymer hain length on line edge roughness robed with a stochastic simulator
ckehard Schöll echnische Universität Berlin nstitut für Theoretische Physik ardenbergstrasse 36 0623 Berlin, Germany Abstract. The impact of various parameters such as photoacid generator PAG concentration, acid diffusion length, and polymer size on the finally obtained line edge roughness LER in chemically amplified photoresists are investigated with a stochastic simulator. A new aspect of the simulations is to start with a polymer matrix modeled by molecular dynamics simulation and subsequently simplify the description of the resist composition for mesoscopically simulating the post-exposure bake PEB and development steps. The results show that decreasing the molecular weight MW of chain-like polymers does not necessarily lead to lower roughness values. Acid-breakable polymers are simulated as well showing that they can lead to improved LER characteristics. © 2007 Society of Photo-Optical Instrumentation Engineers. DOI: 10.1117/1.2817656
The Analysis on Fire Smoke Exhausting Robot Vibration Based on Wavelet Transform
Belt relaxation, which affects a lot on operation reliability of the fire smoke exhausting robot, is hard to detect. In this paper, a new method for belt relaxation feature recognition based on continuous wavelet transform (CWT) is proposed, and a vibration model which simplified the robot as a 2-dof forced vibration system under harmonic excitation is established. The vibration acceleration signal has been collected using the IEPE sensor and data acquisition card, experimental results verified the accuracy of the vibration model, and weak impact signal caused by the belt relaxation was distinguished, that testify the practicability of the CWT method in belt relaxation feature recognition.