| 摘要 |
PURPOSE:To form an emitter region and a thick oxide film region for isolating elements through a self-alignment method by one mask in order to remove a restriction on a distance between both a base electrode and an emitter electrode while preventing a short circuit between a collector and an emitter by using a metal as the base electrode and polycrystalline silicon as the emitter electrode in order to reduce base resistance. CONSTITUTION:An impurity is diffused to a P type base region 811 from a polycrystalline silicon layer 813 to form an emitter region 815. Both ends of the emitter region 815 are determined by thin oxide films 802 protruding from both ends of thick oxide films 808. Consequenly, a transistor of non-walled-emitter structure keeping a predetermined distance by interposing P type base regions 812 of shallow junctions between the emitter region 815 and the thick oxide films 808 for isolating elements can be obtained. The whole surface is oxidized to form oxide films 816 while an emitter is diffused, the oxide films 816 are removd partially while using photo-resist films 817 as masks, and base terminal extracting holes 818 are bored. Lastly, a metal 819 for a base terminal electrode is applied to form a pattern, and a bipolar transistor of structure in the figure (s) is acquired. |
