A semiconductor device including a semiconductor substrate 1 and at least one first column-shaped semiconductor layer 10 of a first channel type formed on semiconductor substrate 1 in order of first, second and third regions, and having a side surface. At least one second column-shaped semiconductor...http://www.google.com/patents/US5311050?utm_source=gb-gplus-sharePatent US5311050 - Semiconductor vertical MOSFET inverter circuit
