| 摘要 |
PURPOSE:To make it feasible to equalize the characteristics of monitoring transistor and circuit constituting transistor by a method wherein electrodes formed of polycrystalline semiconductor layers and wiring layers are respectively isolated and ten high concentration impurity is added to overall surface of polycrystalline semiconductor layers at least forming electrodes. CONSTITUTION:A nitride silicon film 21 is selectively etched to isolate electrodes and wiring layers from one another. Later a polycrystalline semiconductor layer is selectively oxidized utilizing the nitride silicon film 21 as a mask and then the nitride silicon film 21 and a thin oxide film 20 on a base electrode are removed while P-type high concentration impurity is added to be oxidized forming an oxide film around 2,000Angstrom thick on the base electrode. Next the nitride silicon film 21 and the thin oxide film 20 on emitter and collector electrodes are removed and then N-type high concentration impurity is added while the nitride film 21 and thin oxide film 20 on the other polycrystalline semiconductor and another oxide film on the base electrode are removed. The electrodes may be provided with equal characteristics respectively since high concentration impurity is added to a overall surface of electrode to be junctioned with the same transistor characteristics monitor pattern. |
