dc.description.abstract | In the semiconductor packaging and testing industry, many raw materials (such as flammable chemicals, strong acids, strong alkalis, strong oxidizing substances and flammable gases) are used in various processes equipment operated at high temperatures according to the process requirements. While the products are regulated by the relevant laws and regulations, these laws and regulations are not as clear and specific as the standards that can be followed in foreign countries, resulting in that enterprises can only rely on the experience to set up their equipment procurement specifications. In this case, it is easy to derive the fire caused by poor equipment safety design and improper on-site management. In addition, the design of the plant is mostly in a closed environment, which leads to the difficulty of people evacuation and disaster relief when the fire occurs. In this study, the Failure Mode and Effect Analysis (FMEA) and EMI S10 risk assessment method are used to analyze the hazards that can be caused in the process of equipment with high-temperature operation (i.e., High Temperature Equipment) by the functional failure of apparatus components, exhaust system and the safety interlock devices, and study the improvement countermeasures according to the risk assessment results.
Using a semiconductor packaging and testing industry as a case, the failure analysis of the fire project caused by the process of High Temperature Equipment reveals that (i) among the Equipment Components, the highest risk priority number is when the element material is carbonated (RPN was 320); (ii) in the Exhaust System, when the pipeline full of internal condensation, the highest risk priority number is scored 392; (iii) among the Safety interlock System, the highest risk priority number of the safety interlock devices and the temperature detection devices are scored 336. According to the analysis of various failure items, it was found that the reason of the high risk priority, apart from causality, the general problems are lack of existing prevention and detection deficiencies, which leads to the failure to prevent the occurrence. This study also takes how to early prevention of failures as an improvement strategy to compare the differences between before and after improvement that is made. It is found that the abnormity of the equipment components is carbonated by the element material, the RPN scored is reduced to 128; the RPN scored of the safety interlock system is reduced to 96, and the RPN scored of the temperature detection system is reduced to 144; in exhaust pipe, the abnormal internal condensation in the pipeline which RPN scored fell from 392 to 112. From the outcome of the improvement, it is known that the Standards should be set up early in the stage of equipment planning and evaluation to reduce the failure rate of process equipment during operation.
According to the above results, the risk value of internal condensation of exhaust pipeline is the highest, resulting in condensation phenomenon caused when a high temperature gas contacting with cold surfaces. The second high risk value is the safety interlock system, because the equipment machine is not connected with the safety interlock devices. The element material carbonation ranks the third place, because the component temperature exceeds the circuit insulation temperature. Hence. the above projects in the management control should be strengthened via personnel routine testing, cleaning frequency and regular infrared thermal imaging instrument to measure temperature; further, in engineering control, a condensation collecting plate and the exhaust flow detector can be set up inside the exhaust pipe and safety interlock system should controlled by double and double loop protection devices; lastly, the material carbonation of the circuit material should be replaced with a heat-resistant material. | en_US |