1. A monomer of isoflavonyl derivative is one component of polymer being applied to a semiconductor photolithographic process using 248 nm, 193 nm or 157 nm of exposure wavelength of eximer laser as an exposing light source for an antireflective coating layer, a chemical formula of said monomer represents as follows: 8 wherein, R 1 ˜R 7 represent independently hydrogen, methoxy, hydroxy, halogen, aldehyde, C 1 ˜C 6 represent alkoxyalkyl, or C 1 ˜C 5 represent alkoxyalkane, and R 8 represents hydrogen or methyl group.