A Monte Carlo Simulation of Damage to the Gate Oxide of a MOSFET from Electron Beam Lithography.

This work uses a single-scattering Monte Carlo simulation of electron-solid interactions to predict the effects of electron lithography damage in the gate oxide of MOSFETs with gate lengths of 0.5 and 0.25micron. Both 20 and 50 KeV electron energies are examined. Electron radiation can cause significant disorder in the gate oxide and the paper discusses possible solutions to minimize the electron damage. One solution examined in detail is the effect of the thickness of an Aluminum barrier layer (in the case TiN). The paper also explores the generation of x-rays by electron lithography. X-ray damage to the gate oxide is calculated to be small.