Electronic device having electrode with high area density and improved mechanical stability

An electric device including an electric element, the electric element comprising a first electrode having a first surface and a pillar, the pillar extending from the first surface in a first direction, the pillar having a length measured from the first surface parallel to the first direction, the pillar having a cross section perpendicular to the first direction and the pillar having a sidewall surface enclosing the pillar and extending in the first direction,

• wherein the pillar comprises any one of a score and a protrusion extending along at least part of the length of the pillar for giving the pillar improved mechanical stability,
• wherein the sidewall surface comprises a first region and a second region adjoining each other along a line extending parallel to the first direction, the first region and the second region defining an obtuse angle of inclination with respect to each other, and
• wherein the pillar comprises three protrusions forming angles of about 120 degrees one with the others, and the pillar has a tripod-like cross-section perpendicular to the first direction.