ALUMINA CORROSION IN DEIONIZED WATER

Abstract

The corrosion behavior of alumina (Al2O3) layer after exposed to deionized water (DI) is studied. This work focuses on the amorphous alumina which is formed via sputtering process, the process that can be found in many microelectronic industries. The corrosion test was conducted by immersing the alumina coated coupon in DI water at different temperature (from 25-80°C) and various period of time. The formation of the corrosion in terms of defect formed on the surface of the coupon is monitored by using scanning electron microscopy (SEM). From the result, it showed that the defect begins appearing at 50°C, and tends to become severe when the temperature and the immersion time were increasing. Fourier transform infrared spectroscopy (FTIR) indicated that the main functional group of O-H is found after the defect was formed on the surface. Therefore, it is pointed out that such defect is a result from hydrolysis reaction between amorphous alumina and water. The effect of other factors such as pH of water, ions in water, the amount of oxygen dissolved in water and the electron transfer are also investigated and reported. The obtained results are not only aimed to describe this phenomenon or lead to the prevention of this problem but also important as fundamental understanding about the corrosion behavior in basic solution. This knowledge can be used for further improvement and application in microelectronic industries.