Enhance Scheduling System to Improve Cost-effective Semiconductor Wafer Standard Clean Acid Usage

• Main Authors: Yung-ChingChien, 簡永青
• Other Authors: Tzone-Yi Wang
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/4n56pm

碩士 === 國立成功大學 === 工程科學系碩士在職專班 === 106 === Semiconductor manufacturing is a capital and technology intensive industry. In a factory, each machine has its special function in the semiconductor production process, and uses a lot of dangerous chemicals of various kinds. In order to avoid human errors in operations and increase the yield rate of machines, factories usually use some scheduling system to estimate the timings for product flows to enter machines, to choose machines with right functions, and to reduce machines’ waiting time to increase the production capacity. For the time being most scheduling systems uses only general information of products and machines as the basis for the final schedule. The chemical information of each machine is not used precisely on the first hand in the scheduling process, which causes the system to generate obviously imprecise schedules for changing machines’ chemicals. Engineers need to intervene from time to time to adjust timings for changing machines’ chemicals based on their experiences. Error judgements do happen, which causes products scraped because of the delay to entering to machines. Engineers are sometime overloaded, not to mention factories are also put under risks. This study focuses on improving one of the manufacturing procedures, i.e. washing the wafers in a machine, in the scheduling system of a semiconductor factory. This procedure in a machine is to wash the wafer in the unit of a batch of wafers or a single wafer in the machine. Possible contaminants on a wafer is removed by soaking in or by spraying chemicals on the wafer, followed by ultrapure water washing to remove impurities. This is to clean the contaminants such as the particle, organic, inorganic, metal-ions, etc. There are five factors to consider in this research, including equipment, process, wafer, human, and schedule system. Taking into account the limitation of these factors, and using calculated data of the factors, the improvement on a schedule system can increase product efficiency of a factory and reduce its total cost and human resource requirement. It can make the future of the industry 4.0 and unmanned factory possible