| 摘要 |
PURPOSE:To obtain a high performance IC apparatus through formation of base and emitter by using a metal silicide for leadout of base in view of reducing a resistance and by forming base and emitter on the self-alignment basis utilizing growth of silicides. CONSTITUTION:A buried collector 2 and a epitaxial layer 3 are stacked on an Si substrate 1, forming a collector leadout layer 5 and a base layer 6. Layers SiO2 4, Si3N4 13 are stacked and window is opened selectively and then an Mo 16 is also stacked thereon. An MoSi 17 is formed by the heat processing under the N2 ambient under the control of temperature and time and the length of eaves part 18 is set to the desired value within the range of 0.5-1.5mum. Then, the Mo 16 is removed by phosphoric acid and an SiO2 19 is formed on the MoSi 17 through high temperature heat processing in the O2 ambient. After forming an emitter layer 7, the base, emitter and collector electrodes 10-12 are attached. The space between base and emitter is kept at 1mum or less in such a structure and moreover since the resistance of MoSi 17 is low, an external resistance of base can be reduced up to about 1/5 of the ordinary one, thus extremely improving the high frequency characteristic. |
