- 學位論文
不同回風方式對潔淨室流場及溫度分佈影響
Effects of Different Return Air System Designs on Airflow Characteristics and Temperature Distributions in a Cleanroom
摘要
潔淨室為產生均一化的溫度分佈和稀釋污染源的生產環境，除非是特別需求，大多採用非單一方向流潔淨室系統，但機台本身產生的熱能及製造生產所產生的微粒，因熱浮力上升而與FFU向下送的氣流衝突擴散使製程污染威脅性提升。為解決此問題，本研究開發在地化氣流分佈系統，意即使用天花板回風再搭配風機增加回風量之系統，以維持潔淨室潔淨度且有效移除機台產生之熱負荷，此系統由Fan結合Dry Coil之單體，吾人稱之FDCU (Fan Dry Coil Unit)。2008年本研究中心建立此系統，並進行首次研究，研究結果顯示FDCU回風系統相較於傳統牆回風系統可提升33%以上的污染物排除效果；透過FDCU回風系統能使供風層維持正壓，避免外氣洩入，造成室內恆溫恆濕失控。本文將以相同潔淨室為基石，利用超音波風速計量測潔淨室流場，研究FDCU回風系統在不同供風層壓力下潔淨室內速度場、紊流強度，更與傳統牆回風方式比較潔淨室內製程機台運作時溫度分佈變化與流場特性。研究結果顯示潔淨室內有高發熱製程機台運作下FDCU回風系統相較於牆回風系統能提供較佳的污染物移除流場及溫度分佈。
並列摘要
A non-unidirectional airflow cleanroom is one of the most common systems applied in semiconductor industries to control the concentration of airborne particles and the relevant temperature and relative humidity ranges; however, the controlled manufacturing environment is prone to be challenged by the wide spread of hot air and contaminants dissipated from the process tool to surrounding area, resulting in the collision of the uprising hot air current and the downward cold air from ceilings. To effectively remove the dissipated heat and maintain the cleanliness level within requirements, previous studys proposed an innovative fan dry coil units (FDCU) return air system, consisting of ceiling-supply and ceiling-return fan/coil, and indicated that the FDCU return air system can effectively eliminate more than 50% of particles from the cleanroom, compared with a conventional ceiling-return air and wall-supply air system. This study further investigatesd the effect of FDCU-return air system on airflow characteristics and temperature distributions within the cleanroom. A three dimensional ultrasonic anemometer and multiple thermocouples were applied to measure the three components of air velocity and temperature distributions, respectively. Comparisons of velocity vectors, turbulence intensity and the temperature distribution between the FDCU-return air system and the conventional wall-return air system were presented in the study. The results show that FDCU-return air system can significantly provide better air motion characteristics and temperature distributions in the case of a high heat source, compared with the wall-return air system.