Method of manufacturing semiconductor device

摘要

A semiconductor device includes a storage node contact plug, a bit line in communication with to the storage node contact plug, and an expansion unit formed on a sidewall of the bit line. Thermal expansion of the expansion unit serves to increase capacitance by ensuring a distance between the bit line and the storage node contact plug, thereby improving a sensing margin. A cell characteristic such as a record recovery time (tWR) may be enhanced.

主权项

1. A semiconductor device, comprising:
a bit line contact plug formed over a semiconductor substrate; a bit line coupled to the bit line contact plug, the bit line including a bit line conductive layer and a hard mask layer; and an expansion unit disposed on a sidewall of the bit line conductive layer and the bit line contact plug, wherein a width of a central portion of the expansion unit is greater than a width of an upper portion of the expansion unit and a width of a lower portion of the expansion unit.