| 摘要 |
PURPOSE:To unnecessitate the performance of patterning on an Si3N4 film by a method wherein, pertaining to the method of formation of the emitter electrode window of the semiconductor integrated circuit (IC) consisting of a bipolar semicoductor element, an etching process is performed on a polycrystalline silicon film instead of performing said process on an Si3N4 film. CONSTITUTION:An Si3N4 film 12 is grown on an N type silicon substrate 11, and after a patterning has been performed, an SiO2 film 13 is formed by performing heat treatment. Then, a boric ion is implanted from the Si3N4 film 12, and a P type base region 14 is formed. A base electrode window 15 is provided on the Si3N4 film 12, a polycrystalline silicon film 16 is coated on the upper surface of the above, an Si3N4 film 17 is additionally coated thereon, and a patterning is performed on the film 17. Then, the exposed polycrystalline silicon film is transformed into an SiO2 film 18 by performing heat treatment. A patterning is performed on a resist film 19, the region containing the emitter electrode window is exposed, and the exposed Si3N4 film 17 and the exposed polycrystalline film 16 located below the film 17 are removed by etching. Then, an Si3N4 film 21 is coated on the whole surface, and a window is provided on an emitter electrode 22. |
