The work is devoted to modeling the distribution of the intensity of actinic radiation over the photoresist surface in the photolithography process.
One of the fundamental processes in modern microelectronics technology is the process of optical photolithography. Modeling is caused by the problem of predicting the quality of the structures obtained, for the formation of which the photolithography process is used and possible types of defects arising in this case: distortions in the transfer of the dimensions of topological elements (size leaving), double edge. One of the solvable problems of modeling is the prediction of the minimum possible topological size of the structures obtained during this process.
The work discusses the modeling of the process of optical photolithography taking into account such phenomena as: diffraction and nonexextreme distribution of radiation. The model allows us to consider only the simplest case  a slit or a hole through which radiation propagates along the surface of a photoresist. The initial data for the modeling process are: the radiation wavelength, the gap between the photoglass and the photoresist layer, the size of the topological element. From these data, the wave factor is calculated, which determines which case of diffraction redistribution will be formed: Fresnel, Fraunhofer or the transition case. The transition and the Fresnel case are combined into one simulation algorithm and are calculated using a single scheme  using the Chebyshev polynomial. The Fraunhofer case is calculated using a different, simpler scheme.
Note: graduate work is protected in 2000. The program is ported to IDE Delphi XE2 in 2018.
