| 摘要 |
PURPOSE:To transfer a pattern precisely in case an opening is provided in the thin part of a partly different thick layer formed on a semiconductor substrate, by a method wherein a glass mask is covered so that light is shielded over the area from a thinner part to a thicker part. CONSTITUTION:A negative type photoresist 14' is deposited over a thin oxide layer 13' on a collector contact N' region 12' of an n-silicon substrate 11', and a glass mask 15' with a dark part 16' is laid on the photoresist 14' so that a light beam is shielded over the area ranging from a part of a thin oxide layer to a part of a thick oxide layer. Subsequently, by exposing the surface to an ultraviolet beam, a window is transferred on the photoresist 14' under-neath the dark part 16'. The oxide layer 13' is etched through said window to form a perforation for collector contact use. The n type photoresist 14' adhered on the thin oxide layer 13' can prevent from irradiation of an irregular reflection light because the photoresist 14' is covered by the dark part 16' of the mask 15' at its stepped part A''. |
