Organic Distributions in Dried Alumina Green Tape

Distributions of organic binder (poly(vinyl butyral) (PVB)) and plasticizer (dibutyl phthalate (DBP)) in alumina green tape dried at different temperatures are studied. More PVB and DBP are observed on the bottom (Mylar side) than on the top surface (air side) of the green tape. Inside the green tape, however, PVB distribution, which remains relatively unchanged with drying temperature in the range of 30°–80°C, increases with distance from the bottom to the top. In contrast, the DBP concentration remains relatively unchanged with the depth of green tape when the drying temperature is <50°C. At 80°C, however, a significant drop in DBP concentration near the top surface of green tape is found. Mathematical analysis using the finite difference method is completed to describe the PVB distribution in alumina green tape, and the results show reasonable agreement with experimental observations.