Webinar:
LAB Simulation of E-BEAM Lithography

Speaker:

Nezih Ünal, Qing Tan, Aditya Reddy – GenISys GmbH

Takeaways:

  • Absorbed energies can be modelled well by convolution of MC-PSF with layout
  • Threshold model is a easy and quick way for resist contour modelling and analysis of litho quality (CD/Dose sensitivity, process window)
  • Resist development process is a key contributor to litho result
  • Development rate model can be used for e-beam lithography
  • Development rate function can be derived from experimental contrast curves
  • 3D simulation is useful to analyze and optimize resist development effects for single layer and multi-layer processes

Summary:

The webinar is building on the webinar series “Proximity Effect in E-Beam Lithography” where simulation has been user to explain electron scattering, spread of energy and proximity effect, the transfer of the absorbed energy to the resist feature. This webinar is focusing the simulation itself making the connection of simulating the 2D and 3D point-spread-function (PSF) by Monte-Carlo-Simulation (TRACER), computing the 2D (x-y) absorbed energies and resist contour with the simulation feature of BEAMER, and simulating the 3D absorbed energies and resist development process using the LAB 3D simulation software. The value of 3D resist development simulation will be demonstrated for single layer and multi-layer resist application and use cases.

  • E-Beam exposure simulation
    • Monte-Carlo simulation of electron scattering for 2D / 3D PSF
    • Computation of absorbed energies by convolution of layout with PSF
    • Threshold model for deriving the resist contour from absorbed energy
  • 3D resist development simulation
    • PSF and absorbed energy over resist thickness
    • Resist development rate model
    • How to get from contrast curve to development rate
  • Use cases and application for 3D simulation
    • Single layer binary lithography
      • lateral development effect
      • resist profile optimization by “Over-Dose-Under-Size” (ODUS)
    • Multi-layer processes
      • Double layer undercut control
      • Dolan Bridge
      • T-Gate
    • 3D greyscale lithograph