Numerical modeling of atomic layer deposition supercycles

Kunene, Thokozani Justin; Coetzee, Rigardt Alfred Maarten; Tartibu, Lagouge K.; Jen, Tien‐Chien

doi:10.1016/j.matpr.2022.02.083

Cited by 3 publications

(3 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, the choice of pulse time should be decided by considering the overall process. The ALD process is sometimes optimized by employing novel operations of the ALD valve, such as the "super cycle" 48 (also known as the "discrete feeding method" 26 ), where the cut-in purge between short pulses can remove the physisorbed precursors enhancing the surface coverage of precursors. The "discrete feeding method" can increase the nucleation density at the initial stage of film deposition by improving the surface coverage of precursors and reduce the critical thickness (the minimum thickness for continuous film formation), which is more conducive to the preparation of ultra-thin films.…”

Section: Operation Of the Ald Valvesmentioning

confidence: 99%

CFD Simulation of the Dosing Behavior within the Atomic Layer Deposition Feeding System

Yuan

Ping

Lee

et al. 2023

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

The effective operation of atomic layer deposition (ALD) feeding system is the premise of realizing specific ALD processes. In the present work, a detailed computational fluid dynamics (CFD) model of the feeding system has been developed and validated, which accounts for the roles of ALD valves and manifolds. A numerical simulation of the compressible fluid flow and heat/mass transfer within the feeding system was conducted. The dosing amounts and the spatiotemporal distributions of the precursors can be accurately predicted using the CFD model, as validated by experimental results. Different precursors, operating conditions, and structures of the feeding system were simulated and analyzed to examine the operating flexibility of the feeding system. The simulation results can be adopted as the upstream boundary conditions for simulations of the ALD process in the reaction chamber. The substrate-scale simulation indicates that the effect of the feeding system on the film deposition is highly related to the surface kinetics of ALD. The present work can serve as a guide for the development and optimization of different ALD-based processes via proper operation and even the design of the feeding system.

show abstract

Section: Operation Of the Ald Valvesmentioning

confidence: 99%

CFD Simulation of the Dosing Behavior within the Atomic Layer Deposition Feeding System

Yuan

Ping

Lee

et al. 2023

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…Let us note that atomic layer deposition (ALD) has been employed for the last years, and represents an alternative to other vacuum processes (sputtering, chemical vapor deposition, etc.). [ 19–21 ] Cho et al demonstrated amorphous IGZO TFTs with mobility of 48.3 cm 2 Vs −1 by cation composition investigation at a low annealing temperature of 250 °C. [ 22 ] ITZO TFTs with mobility of 27.7 cm 2 Vs −1 were also achieved.…”

Section: Introductionmentioning

confidence: 99%

Light Effect on Amorphous Tin Oxide Thin‐Film Transistors

Avis,

Billah,

Jang

2024

Advanced Photonics Research

View full text Add to dashboard Cite

Amorphous tin oxide (a‐SnOx) is a potential transparent oxide semiconductor candidate for future large‐area electronic applications. The thin‐film transistor (TFT) mobilities reach ≈100 cm2 Vs−1, a mobility higher than other multiple cation‐based oxide semiconductor TFTs. Few optical properties have been reported so far and therefore both the effect of visible light and negative bias illumination stress (NBIS) on a‐SnOx TFT performances, known to dramatically impact oxide semiconductor‐based TFTs, have been investigated. The variation of density of states (DOS) due to NBIS by device simulation is analyzed, and a fourfold increase of the donor‐like states and a decrease in the band edge DOS from 2.3 to 2.0 × 1019 cm−3 eV−1 are showed. The evaluation of the effect of neutral, singly, and doubly ionized oxygen vacancies by density functional theory using 95 atoms reveals not only states in the gap of SnO2, but also variations in the electron density, and modifications in the crystal parameters compared to a structure without an oxygen vacancy. Material and device simulation analysis reveal that the oxygen vacancies have a dramatical impact on the DOS in the gap of SnO2 and can explain the NBIS phenomenon observed in a‐SnOx TFT.

show abstract

“…These models are instrumental in investigating the impact of ALD process parameters on aspects like film growth, thickness, and growth per cycle (GPC). A few models that leverage fluid dynamics are used to simulate the ALD process in a threedimensional context [19][20][21]. These fluid dynamics models, or those involving transport phenomena, can become computationally and mathematically complex depending on the system geometry, requiring increased computational capacity [17,20,22,23].…”

Section: Introductionmentioning

confidence: 99%

Exploring TMA and H2O Flow Rate Effects on Al2O3 Thin Film Deposition by Thermal ALD: Insights from Zero-Dimensional Modeling

Karnopp,

Neto,

Vieira

et al. 2024

Coatings

View full text Add to dashboard Cite

This study investigates the impact of vapour-phase precursor flow rates—specifically those of trimethylaluminum (TMA) and deionized water (H2O)—on the deposition of aluminum oxide (Al2O3) thin films through atomic layer deposition (ALD). It explores how these flow rates influence film growth kinetics and surface reactions, which are critical components of the ALD process. The research combines experimental techniques with a zero-dimensional theoretical model, designed specifically to simulate the deposition dynamics. This model integrates factors such as surface reactions and gas partial pressures within the ALD chamber. Experimentally, Al2O3 films were deposited at varied TMA and H2O flow rates, with system conductance guiding these rates across different temperature settings. Film properties were rigorously assessed using optical reflectance methods and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The experimental findings revealed a pronounced correlation between precursor flow rates and film growth. Specifically, at 150 °C, film thickness reached saturation at a TMA flow rate of 60 sccm, while at 200 °C, thickness peaked and then declined with increasing TMA flow above this rate. Notably, higher temperatures generally resulted in thinner films due to increased desorption rates, whereas higher water flow rates consistently produced thicker films, emphasizing the critical role of water vapour in facilitating surface reactions. This integrative approach not only deepens the understanding of deposition mechanics, particularly highlighting how variations in precursor flow rates distinctly affect the process, but also significantly advances operational parameters for ALD. These insights are invaluable for enhancing the application of ALD technologies across diverse sectors, including microelectronics, photovoltaics, and biomedical coatings, effectively bridging the gap between theoretical predictions and empirical results.

show abstract

Numerical modeling of atomic layer deposition supercycles

Cited by 3 publications

References 37 publications

CFD Simulation of the Dosing Behavior within the Atomic Layer Deposition Feeding System

CFD Simulation of the Dosing Behavior within the Atomic Layer Deposition Feeding System

Light Effect on Amorphous Tin Oxide Thin‐Film Transistors

Exploring TMA and H2O Flow Rate Effects on Al2O3 Thin Film Deposition by Thermal ALD: Insights from Zero-Dimensional Modeling

Contact Info

Product

Resources

About