| 초록 |
polyimides contain carbonyl groups in their backbone, so that they have higher water absorption and dielectric constant than less polar polybenzoxazoles(PBO). 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(PSPBO) was highly anticipated. A conventional PSPBO can be consisted of photo active compound(PAC), esterified diazonaphthoquinone(DNQ) and PBO precursor, PHA(polyhydroxyamide). The PHA has phenolic hydroxyl group, so that can promote dissolution of the polymer in an aqueous alkaline developer. The hydrogen bonds between hydroxyl group of PHA and DNQ inhibit the dissolution. But, after exposure with UV light, DNQ is converted to indene-carboxylic acid or sulfonic acid compounds which promote dissolution. |
