Abstract
We have developed a positive working photosensitive polybenzoxazole (PBO) for semiconductor surface coating material. Now it has already been used for buffer coat to protect electrical circuit on IC chip in the semiconductor market. Cure film of this photosensitive PBO has not only low water absorption (0.3%) and low dielectric constant (2.9) but also high adhesion to substrate such as SiO2 etc. And the patterning profile has suitable taper shape after development and curing. These properties are useful for application of interlayer dielectric film for Multi Chip Module (MCM ) package and Wafer Level Package (WLP).