NFF Cleanroom Environment
A cleanroom is a controlled environment in which the concentration of pollutants such as dust, airborne particles and chemical vapors is kept within specified limits. These pollutants may be generated from the facilities (e.g. spills and leaks), people (e.g. skin flakes and oil) or even the research products themselves (e.g. silicon chip fragments). Any of these pollutants can seriously affect the output. That is why a cleanroom is needed.
In the NFF cleanroom, the air exchange rate, air exchange direction, pressure, temperature, humidity and particle count are all strictly controlled. HEPA (high efficiency particulate air) filters are installed to remove very small particles. These filters can remove up to 99.9997% of particles as small as 0.3 micrometers in diameter. Make-up air is filtered for dust removal before entering the cleanroom while the air inside the cleanroom is constantly filtered to remove internal pollutants.
In order to minimize the human contamination of the research products in the cleanroom, those who wish to enter must first put on a set of cleanroom garments consisting of a hair cover, a face mask, a cleanroom gown, gloves, shoe covers and boots. They will then have to walk through an air shower at the entrance for pollutants removal.
The NFF cleanroom is split into three areas: the class 10,000, class 1,000 and class 100 where houses five equipment modules, Mask Making Module, Photolithography Module, Wet Etching and Sputtering Module and Thermal Processing and Implantation Module. To ensure the standard of the cleanroom is maintained, the particle level in different areas is regularly monitored with a particle counter. The cleanroom regulations are also strictly enforced to prevent contamination.