Abstract: Castor oil was used as the dispersant of AlN tape casting slurry, its efficiency was evaluated by the method of deposition. The result
indicates that when the amount of castor oil is around 1%-1.5% of the weight of AlN powders, the most homogeneous slurry can be
achieved. Fourier transform infrared (FTIR) was firstly introduced into the studying of interactions between inorganic AlN particles
and organic dispersants. The results show that carbonyl is the main functional group that affects the adsorption property. The
carbonyl and nitride atom forms a conjugate structure of n-π, which makes a stable adsorption.

Key words: infrared analysis, AlN, dispersant, tape casting