| 摘要 |
PURPOSE:To improve the uniformity and reproducibility of the characteristics of a transistor by forming an opening for a base contact and shaping a polycrystalline silicon film in film thickness of not less than half the width of the opening. CONSTITUTION:Openings 25 are formed to poly Si films 13, 15 and a first insulator film 12, and a poly Si film 17' is shaped in film thickness of not less than half the width of the patterns of the holes 25. Consequently, the holes 25 are buried completely. Since the width of the patterns extends over approximately 0.4mum at that time, approximately 0.3mum is proper as the thickness of the poly Si films, and the holes are buried, thus forming flat structure. Accordingly, the uniformity and reproducibility of a distance between a base and an emitter can be improved without increasing the number of processes, and the lowering of base-contact resistance and the betterment of the accuracy of the patterns can be expected, thus anticipating the enhancement of the yield and reliability of a semiconductor device. |
