| 摘要 |
PURPOSE:To make an ohmic contact excellent by a method wherein a silicon layer containing a conductive type deciding impurity with concentration higher than that of substrate is laid between a silicon substrate and a metallic layer. CONSTITUTION:An N<-> type epitaxial region 2 doped with phosphorus P is formed on an N<+> type silicon substrate 1 doped with antimony Sb further to form a P type base region 3 and an N type emitter region 4. A window is opened on an oxide film 5 to evaporate aluminum and then an emitter electrode 6 and base electrodes 7 are formed by means of patterning process.Finally the backside of substrate 1 is ground to form a silicon layer 9 by means of sputtering process utilizing a target containing P with the solid solution limit larger than that of antimony Sb in silicon further forming a collector electrode 8 made of metallic such as Cr, Ni, Ag layer 10 by means of sputtering or evaporating process. |
