Options
2010
Conference Paper
Titel
Practical resist model calibration for e-beam direct write processes
Abstract
With the constantly improving maturity of e-beam direct write exposure tools and processes for applications in high volume manufacturing, new challenges with regard to speed, throughput, correction and verification have to be faced. One objective of the MAGIC high-throughput maskless lithography project [1] is the application of the physics-based simulation in a virtual e-beam direct write environment to investigate proximity effects and develop comprehensive correction methodologies [2]. To support this, a rigorous e-beam lithography simulator for the feature scale has been developed [3]. The patterning behavior is determined by modeling electron scattering, exposure, and resist processing inside the film stack, in analogy with corresponding simulation capabilities for the optical and EUV case. Some model parameters, in particular for the resist modeling cannot be derived from first principles or direct measurements but need to be determined through a calibration proce ss. To gain experience with the calibration of chemically amplified resists (CAR) for e-beam lithography, test pattern exposures have been performed for a negative tone CAR using a variable-shaped beam writer operating at 50kV. A recently implemented model calibration methodology has been applied to determine the optimum set of resist model parameters. While the calibration is based on 1D (lines & spaces) patterns only, the model results are compared to 2D test structures for verification.