| 摘要 |
PURPOSE:To obtain a positive type resist sensitive to ultraviolet rays having high sensitivity and resistance to dry etching, by using a copolymer of phenyl vinyl ketone and a vinyl monomer. CONSTITUTION:A copolymer of phenyl vinyl ketone amounting to >=30mol% expressed in terms of monomer mole %, and methyl methacylate, phenyl methacrylate, styrene, etc. is coated on a silicon substrate to give a resist. A desirable molecular weight Mn of the resist resin is as follows: 4,000<=Mn<=50,000. The resist resin is exposed to far ultraviolet rays, then developed with methyl cellosolve, methyl ethyl ketone, or the like, and subjected to dry etching by gaseous CF4 plasma. The copolymerized ''phenyl vinyl ketone units'' exhibit high selective decomposibility by the far ultraviloet rays, and aromatic groups have resistance to dry etching. |
