| 摘要 |
PURPOSE:To increase an exposure margin by coating a semiconductor substrate with photoresist added with dye to form a reversibly tapered pattern of the photoresist, exposing the photoresist with a large quantity of exposure amount, and controlling the angle of the reverse taper. CONSTITUTION:A semiconductor substrate 1 is coated approx. 1-3mum of thickness with positive type photoresist 2 added with dye, heat treated (prebaked) at approx. 100 deg.C in a dry atmosphere, exposed with a photomask 4, and the photoresist 2 is varied in a reversibly tapered shape. Since the dye in the photoresist 2 has a light absorption effect, the exposure amount is increased to be 330msec or more. Thereafter, it is heat treated at 90-100 deg.C in an ammonia gas atmosphere so that an exposed part becomes insoluble with alkaline developer, and the whole resist 2 is exposed. It is developed with the alkaline developer such as ammonium fluoride, and heat treated at approx. 100 deg.C to form a reversibly tapered photoresist 5. |
