Method for determining incident angle of particles in three-dimensional cellular model etching process

Abstract

The invention relates to a method for determining an incident angle of particles in a three-dimensional cellular model etching process, which belongs to the field of the etching process in the micro-electron machining; and the method comprises the following steps of selecting two tangent planes which are vertical to an incident plane according to an incident direction of etching particles; respectively selecting surface cellular surrounding an incident point on the two tangent planes, adopting a position coordinate as a data sampling point, conducting fitting calculation by adopting a two-dimensional curve fitting method, and further solving a tangent vector of the incident point on the two coordinate axis directions; and finally conducting cross-product operation for the two tangent vectors to solve the normal surface vector of the incident point, and acquiring the incident angle of the etching particles. A three-dimensional curve fitting problem is converted to two two-dimensional curve fitting to be solved, so that the solution of multi-element equations can be reduced, the calculation complexity is reduced, and simultaneously the treatment of ill-conditioned system of equations in a polygonal curve fitting can be avoided; and the calculation accuracy and the operation speed can be greatly improved.

Description

technical field [0001] The invention belongs to the field of etching process simulation in microelectronic processing, in particular to a method for determining particle incident angles in the etching process for three-dimensional cellular models. Background technique [0002] Etching is an important step in the production of integrated circuits. The simulation of the etching process is a key step in guiding and producing high-quality integrated circuits, and it is also an important tool for better understanding and understanding of etching principles. Due to the simple structure, good stability and easy expansion of the cellular model, it becomes one of the effective methods for etching process simulation. The etching model established by using the three-dimensional cell model is as follows: figure 1 As shown, the simulated area to be etched on the wafer is divided into three-dimensional grids with a cube with a side length of 1, and each three-dimensional grid is a cell; ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problem of selecting the incident angle of etching particles in the three-dimensional cellular model simulation etching process, and to provide a method for determining the incident angle of particles in the three-dimensional cellular model etching process. The surface normal vector on the etched surface enables a fast solution to obtain the incident angle of the etched particle

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