Strain measurements of ULSI devices using LACBED with TSUPREM modeled displacements

Abstract

Large angle convergent beam electron diffraction (LACBED) patterns recorded of trenches in silicon devices were compared with simulated LACBED patterns to determine the strain in the structure. Displacement fields stemming from stress simulations of a 2D device simulator (TSUPREM IV) were used as an input for the LACBED simulations. The LACBED far-fields are very well reproduced by the simulations whereas the near-fields close to the interfaces show that the device simulator overestimates the strain.