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Semiconductor industry is experiencing a rising demand for environmentally friendly processes with the emphasis on green policies and worldwide environmental sustainability. Nitrogen trifluoride (NF3), the most common plasma chamber cleaning agent gas, poses a significant concern as a potent greenhouse gas since it has global warming potential (GWP), 740 times and 6 times higher than that CO2 and N2O. This study investigated the exhaust gas using quadrupole mass spectroscopy (QMS) and analyzed the change in cleaning speed and the type of exhaust gas through plasma monitoring using optical mass spectroscopy (OES). The objective is to lower the use of the amount of NF3 gas in chamber cleaning process to partially contribute the environmental sustainability in the point of semiconductor manufacturing. When a small amount of N2 was added to NF3 whose ratio of 7:23, the cleaning efficiency reached to 90% compared to NF3 gas alone. Addition of N2 positively affected electron density and temperature to increase the F-radical in remote plasma system. In conclusion, 18% of NF3 usage amount was reduced during the Sio2 deposition chamber cleaning process. [ABSTRACT FROM AUTHOR]

Abstract: Nickel manganite spinel (NiMn2O4) based negative temperature coefficient (NTC) thermistors have good thermistor characteristics and stabilities. However, to achieve thermistors with a high B constant, the activation energy should be high, which results in high room temperature (RT) resistivity. To obtain a high B constant and low RT resistivity, NiMn2O4 based nanocomposite thick films with the conducting metal oxide, LaNiO3, were fabricated on a glass substrate by aerosol deposition at room temperature. The NiMn2O4–LaNiO3 nanocomposite thick films showed an RT resistivity as low as 35kΩ cm, which is one order of magnitude lower than that of the NiMn2O4 films, while retaining the high B constant of NiMn2O4 of over 5000K when 25vol.% LaNiO3 was used without any post thermal treatment. [Copyright &y& Elsevier]