| 摘要 |
PURPOSE:To control the junction leak of an inverter transistor as well as the narrow channel effect of an access transistor by implanting boron for channel cut into a groove for inverter transistor isolation more than into a groove for access transistor isolation. CONSTITUTION:A semiconductor storage device is made by isolating each of transistors 1-4 included in a memory cell by an element isolation groove 22 and boron for channel cut is implanted more into a groove for inverter transistors 3, 4 isolation than into a groove for access transistors 1, 2 isolation. Since more boron is thus implanted into the groove for inverter transistor isolation than into the groove for access transistor isolation, the junction leak at an inverter transistor is reduced and yet the narrow channel effect at an access transistor is controlled. As a result, MOS static RAM(SRAM) of high resistance load type can be provided with high density without increasing its standby current. |
