Abstract

As semiconductor node technology advances to below 5 nm, it is vital to control Non-uniformity, Line Edge Roughness (LER), and Line Width Roughness (LWR). These factors are crucial for meeting performance, reliability, and yield goals. This study presents a computational fluid dynamics (CFD) model for optimizing Plasma-Enhanced Chemical Vapor Deposition (PECVD) processes, focusing on the synthesis of thin films such as Silicon Dioxide from precursor gases like Silane and Nitrous Oxide. The model is designed to accurately simulate the complex transport and reaction dynamics within the low-pressure, non-equilibrium plasma environment. The transport of neutral radical species (which form the bulk of the deposited film) is governed by the Reaction-Diffusion-Convection equation. The model incorporates the plasma's effect through two key source terms. The dissociation of precursor gases by energetic electrons will be modeled as a volumetric source term within the transport equations. This term is proportional to the electron density and the electron impact rate coefficient. The deposition reaction at the wafer surface is included via a reactive boundary condition (Robin condition), which equates the arriving diffusive flux to the surface consumption rate. This rate is determined by the radical concentration at the wall and a calculated surface reaction rate constant, defined in terms of the radical's thermal velocity and its sticking coefficient. By integrating specialized plasma-chemistry kinetics with standard fluid dynamics, the model allows quantification of the silicon deposition rates on the wafer surface. The overall objective is to develop a fundamental understanding of the working principles of Plasma Vapor Deposition to achieve more sustainable fabrication of Integrated Circuits (ICs). Specifically, the simulation will be used to determine the driving reaction processes, the spatiotemporal distribution of the main reactants and products, and to quantify the deposition rate of silicon as a function of time, thereby providing fundamental understanding of the plasma processes in semiconductor fabrication.

Publication Date

4-29-2026

Document Type

Thesis

Student Type

Graduate

Degree Name

Manufacturing and Mechanical Systems Integration (MS)

Department, Program, or Center

Manufacturing and Mechanical Engineering Technology

College

College of Engineering Technology

Advisor

Isaac Perez Raya

Advisor/Committee Member

Michael Jackson

Advisor/Committee Member

Satish Kandlikar

Campus

RIT – Main Campus

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