In MCM-D applications, interlayer dielectrics separate and insulate metal conductors to form a three-dimensional interconnection structure. Due to the three-dimensional nature of these structures, the thermal, electrical and mechanical properties of the dielectricmaterials must be known for all orientations in order to correctly design and simulate devices. The most commonly used polymer in microelectronics, polyimide, exists in formulations which have been shown to have a high degree of orientation and exhibit anisotropicproperties.