Field measurement analyses and improvement simulation of airflow parallelism in a wafer-griding cleanroom

¹ Graduate Institute of Precision Manufacturing, National Chin-Yi University of Technology, Taiwan
² Department of Refrigeration, Air Conditioning, and Energy Engineering, National Chin-Yi University of Technology, Taiwan

^* Corresponding author: fjwang@ncut.edu.tw

Abstract

Cleanrooms are essential in the semiconductor industry, where the environment must be strictly regulated to prevent contamination that could affect product quality. However, many factors are crucial, and the process can be complex, such as temperature, relative humidity, airflow distribution, particle counts, and pressure. This study conducted a cleanroom for wafer grinding wheels with the highest level of cleanliness, cleanroom class 1, utilizing a ceiling covered by Ultra-Low Particulate Air (ULPA) filter. In order to ensure that the design conforms to the standard, Testing, Adjusting, and Balancing (TAB) were conducted prior to field measurements. According to the findings, all cleanroom specifications were met. However, the airflow rate exceeds the design, causing the pressurization to increase. In addition, the study also utilized simulation to simulate airflow parallelism to decrease angle deflection. The average airflow velocity measured is 0.42 m/s. By reducing the airflow to the required limit of 0.35 m/s, the deflection of the angle can be reduced by 10%. Other parameters, such as airflow rate and pressurization, remain within the standard. In addition, lowering the airflow rate can lead to energy savings.