Modeling Of Optical Alignment Images For Semiconductor Structures

Abstract

The "wave-guide" model1,2,3,4,5, which can be used to study the light scattering problem in optical alignment, has been extended to include illumination with arbitrary polarization and large numerical aperture (NA) lens. An existing simulator4 has been enhanced to calculate the images of different structures observed under different alignment schemes. It is shown that variations in the polarization conditions and topography may drastically alter the alignment results.

Modeling of optical images in resists by vector potentials

“…This model is essentially the same as that in Ref. [6,7], but the calculation amount is reduced by using the eigenmode orthogonalities. …”

“…[6,7], the wave-guide model is applied to the electromagnetic fields inside a resist . First, the differential equation in Section 2.4 is solved and the eigenmodes for the electromagnetic field are obtained in each layer.…”

Fast 3D lithography simulation by convolutional neural network: POC study

“…We also confine the polarization to TE (Transverse Electric) polarization to simplify the problem. For the CNN training targets we perform electromagnetic simulations by using the 2D version 16 of the 3D waveguide mdel. 6…”

Modeling of optical alignment and metrology schemes used in integrated circuit manufacturing

“…Arc lamp or laser is modeled as the illumination source. Mathematical details about the scattering and imaging models can be found in the literatures [29,28].…”

“…The "wave-guide" model [4,10,18,19,29,28] is used to calculate the scattering matrix S. It is a vector model which solves the Maxwell's equations in two dimensions. The imaging model is developed from the Abbe imaging theory [8] in which traveling light is treated as a linear combination of plane waves.…”