Topography Simulation of Trench Etch Using Monte Carlo Plasma Etch Model with Polymer Re-deposition

1. Introduction

The topography simulation module, Elite has constantly been improved in order to simulate advanced processes, which are becoming more complex with device miniaturization and further integration of VLSI circuits. Elite is a two dimensional topography simulation module that works within ATHENA, and includes the etching and deposition models neccessary to simulate diverse modern technologies.

One of the more important features of Elite , is the physics based Monte Carlo Etch Model, which is more accurate than conventional direction-rate based etching models. The Monte Carlo Etch Model involves calculation of the plasma distribution, and takes into account the redeposition of the polymer material generated as a mixture of incoming ions and etched (sputtered) molecules of substrate material.

In this article, we will discuss the relationship between the process conditions of the reaction chamber and the resulting etched profile. The example combines topography simulation together with plasma sheath reaction and surface reaction modelling.

The pioneering efferts of S. Takagi, et al. [1] reported both experimental results and plasma/topography simulation using the ATHENA/Elite Monte Carlo Etch Model. In this article, we are concentrating on how to specify the many complicated simulation parameters of the Monte Carlo Etch Model, referring to the results and calibration work of S. Takagi, et al. [1].

2. Simulation Model and Parameters

2-1. Incoming ions and neutrals