Design and Optimization of Chemical Mixing System for Vacuum Chambers Base of Simulation Results / Vakum Odaları için Kimyasal Karıştırma Sisteminin Tasarım ve Optimizasyonunun Simülasyon Sonuçları

Öz

Computational fluid dynamics (CFD) is widely used in device design to determine gas flow patterns and turbulence levels. CFD is also used to simulate particles and droplets, which are subjected to various forces, turbulence and wall interactions. These studies can now be performed routinely because of the availability of commercial software containing high quality turbulence and particle models. In order to understand how the gas is brought down to wafer, it is necessary to have a knowledge of the gas flow behavior very early in the design spiral of the Tantalum nitride-Atomic layer deposition (TaN-ALD) chamber by undertaking parametric investigation of the interaction effect between gas flow and the funnel structure. This paper presents such a parametric investigation on a generic TaN-ALD chamber using CFD. The results presented have been analyzed for a total of 11 different cases by varying neck and nozzle angles for a process gas. The gas flow was mainly investigated for the nozzle angles of 4.5, 9, 12 and 20 and the film thickness results were compared with numerical flow patterns. CFD simulations using the turbulence model in ANSYS Fluent v.13 are undertaken. The parametric study has demonstrated that CFD is a powerful tool to study the problem of gas flow–structure interaction on funnel and is capable of providing a means of visualizing the path of the gas under different operating conditions. Özet: Hesaplamalı akışkanlar mekaniği (CFD), gaz akış modelleri ve türbülans seviyelerini belirlemek için tasarlanan cihazlarda yaygın olarak kullanılmaktadır. CFD, türbülans ve cidar etkileşimlerinde farklı kuvvetlere maruz kalan parçacık ve damlacıklarının simülasyonu için de kullanılır. Günümüzde bu çalışmalar, yüksek kalitede türbülans ve parçacık modelleri içeren ticari yazılımların kullanılması ile yapılabilmektedir. Bir gazın nasıl levhamsı haline geldiğini anlamak için, gaz akışı ve huni yapı arasındaki etkileşim etkisinin taahhütlü parametrik araştırma ile Tantalum nitride-Atomic tabaka katmanı odasının (TaN-ALD) spiral tasarımındaki en erken gaz akış davranışının bilinmesi gerekir. Bu makale, CFD kullanılan kapsamlı bir TaN-ALD odası üzerine parametrik bir incelemeyi sunmaktadır. Bir gaz prosesi için toplamda 11 farklı boğaz ve meme açısının sonuçlarının analizi sunulmuştur. Gaz akışı, 4.5o, 9o, 12o ve 20o meme açısı değerleri için incelenmiş ve film kalınlığı sonuçları nümerik akış modelleri ile karşılaştırılmıştır. ANSYS Fluent v.13’de türbülans modeli kullanan CFD simülasyonu üstlenilmiştir. Parametrik çalışma gösterdi ki CFD, huni üzerindeki gaz akışı-yapısı etkileşimi problemini çalışmak için çok güçlü bir araçtır ve farklı çalışma şartları altında gazın yolununun görselleştirilmesini sağlayabilen bir araçtır.

Anahtar Kelimeler

• Vacuum Chamber, Atomic layer deposition (ALD), Computational fluid dynamics (CFD), Wafer film, gas mixing / Vakum Odası, Atomik tabaka tortusu (ALD), Hesaplamalı Akışkan Dinamiği (CFD), Levhamsı Film, Gaz Karışımı

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