초록 |
Photosensitive polyimides have been studied to replace a conventional polyimides since non-PSPI could reduce the number of processing steps in semiconductor packing by removing the photoresist related processes. polyimides contain carbonyl groups in their backbone, so that they have higher water absorption and dielectric constant than less polar polybenzoxazoles. And PBO properties similar to polyimides. Thus, PBO have received increasing interest in microelectronic industry because they have lower water absorption and dielectric constant than polyimides. Thus, the development of photosensitive polybenzoxazole was highly anticipated. A conventional PSPBO can be consisted of photo active compound, esterified diazonaphthoquinone and PBO precursor, polyhydroxyamide. The PHA has phenolic hydroxyl group, so that can promote dissolution of the polymer in an aqueous alkaline developer. |