METHOD FOR FABRICATING BIPOLAR TRANSISTOR OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating a bipolar transistor of a semiconductor device is provided to improve the capacity of a transistor by increasing the base width of the bipolar transistor. CONSTITUTION: The first oxide layer and a nitride layer on a substrate(1) are etched and the substrate is etched. The nitride layer and the first oxide layer only in a portion for the first epitaxial layer(4) are sequentially eliminated. The first epitaxial layer having an opposite type to the substrate is formed and the remaining first oxide layer is removed. The second epitaxial layer(5) having an opposite type to the first epitaxial layer is formed as a base. The second oxide layer is formed and etched by a predetermined portion. A polysilicon layer for forming an emitter(7) is formed. The second oxide layer is planarized to form a buried emitter. The second oxide layer is removed. The first photoresist layer is formed to fabricate a diffusion layer(9) having the same type as a base epitaxial layer in the lower part of a base electrode. After the first photoresist layer is eliminated, the second photoresist layer is formed to fabricate a shallow diffusion layer having the same type as a collector in the lower part of a collector electrode. The second photoresist layer is removed. An interlayer dielectric oxide layer(12) is formed and buried. The buried interlayer dielectric oxide layer is separated. The first metal interconnection(14) is formed to be connected to a lower conductive layer and is etched to form a pattern.