Methods of manufacturing semiconductor devices having self-aligned contact pads

摘要

A semiconductor device includes a substrate having a field area that defines active areas, gate trenches in the substrate and extending in a first direction, a buried gate in a respective gate trench, gate capping fences in a respective gate trench over a respective buried gate, the gate capping fences protruding from top surfaces of the active areas and extending in the first direction, bit line trenches in the gate capping fences, a respective bit line trench crossing the gate capping fences and extending in a second direction perpendicular to the first direction, an insulator structure on inner walls of a respective bit line trench, bit lines and bit line capping patterns stacked on the insulator structures in a respective bit line trench, contact pads self-aligned with the gate capping fences and on the substrate between the adjacent bit lines, and a lower electrode of a capacitor on a respective contact pad.

主权项

1. A method of manufacturing a semiconductor device, the method comprising:
forming a field area that defines active areas in a substrate; forming gate trenches that extend in a first direction in the substrate; forming buried gates in the gate trenches; forming gate capping fences in the gate trenches on a respective buried gate, the gate capping fences protruding from top surfaces of the active areas and extending in the first direction; forming line-shaped pad patterns self-aligned with the gate capping fences and extending in the first direction on the substrate; forming contact pads and bit line trenches by patterning a part of the pad patterns and the gate capping fences to expose at least some areas of the substrate between adjacent gate capping fences, wherein a respective contact pad is formed on the substrate between the adjacent bit line trenches and a respective bit line trench extends in a second direction perpendicular to the first direction; forming a bit line in a respective bit line trench; and forming a lower electrode of a capacitor on a respective contact pad.