Patent ID: 7863174
Filing Date: 2011-01-04
Classification: H01L

Abstract:
1. A vertical pillar transistor comprising: a plurality of lower pillars protruding substantially perpendicular to a substrate and defining a plurality of trenches, the plurality of lower pillars extending along a second direction and separated from each other along a first direction, the first direction substantially perpendicular to the second direction; a plurality of upper pillars, each of the plurality of upper pillars respectively on each of the plurality of lower pillars, and each of the plurality of upper pillars having a width smaller than that of the respective lower pillar; a first insulation part having a substantially uniform thickness on a sidewall of at least one of the plurality of lower pillars; a second insulation part on the first insulation part to fill a gap between an adjacent pair of the plurality of upper pillars; and a word line on the second insulation part and extending between facing sidewalls of the adjacent pair of upper pillars along the first direction, wherein the first insulation part blocks an entrance of each of the plurality of trenches to form a void in at least one of the plurality of trenches.