Cleaning is an important process step throughout the semiconductor industry chain, used to remove impurities that may exist in each step of semiconductor wafer manufacturing, wafer fabrication and package testing to avoid impurities affecting chip yields and chip product performance. The number of cleaning steps accounts for more than 30% of all chip manufacturing process steps and is the largest process among all chip manufacturing process steps. As technology nodes continue to advance, the number and importance of cleaning processes will continue to rise.
As an important tool for wafer cleaning process, cleaning carrier play a role in carrying and transporting wafers during the manufacturing process, and their material selection and structural design affect the yield and efficiency of wafer production. According to different requirements, wafer carriers are generally made of fluoroplastics (PTFE, PFA, PVDF), polypropylene through CNC machining or injection molding.
The general method of semiconductor tank cleaning is: first wafers placed in the cleaning wafer carrier, and then the cleaning wafer carrier with wafers into the cleaning tank, the cleaning tank is equipped with cleaning agent and has an ultrasonic generation device.
Since the cleaning cassette is to be in contact with the drug solution, its acid and alkali resistance needs to be considered, so a chemically stable material is preferred. In addition, since the planter cassette has to be in contact with the wafer, a material with smooth surface is required in order not to damage the wafer, and at the same time, its sufficient rigidity, which is not easily deformed, is also considered in order to meet the effective support and clamping.
The components of the cleaning cassette can be made of the same material, which can avoid the cassette being corroded by acid and alkali media in use and causing secondary pollution. According to different requirements, it can be made of fluoroplastic (PTFE, PVDF, PFA) or polypropylene (PP). Fluoroplastic cleaning cassette can be used to immerse in organic or inorganic cleaning agent for cleaning, when the cleaning agent is organic cleaning agent, the use of temperature below 80 ℃, the material of the cleaning cassette can be used polypropylene. In addition, there are cleaning cassette manufacturers to surface treatment of the material, so that the cleaning cassette can quickly remove water, to achieve quick drying and energy-saving effect.
In addition to the material requirements, the structure requirements of the cleaning cassettes are also very high. Washing cassettes are equipped with washing hole slots to enhance the washing, draining and drying effect, and the compact structure, stable and reliable cleaning and drying process can reduce the wafer fragmentation rate, and also ensure that the semiconductor wafer can fully contact the cleaning agent.