Semiconductor device having buried channel array

摘要

A semiconductor device includes a field regions in a substrate to define active regions, gate trenches including active trenches disposed across the active region and field trenches in the field regions, and word lines that fill the gate trenches and extend in a first direction. The word lines include active gate electrodes occupying the active trenches, and field gate electrodes occupying the field trenches. The bottom surface of each field gate electrode, which is disposed between active regions that are adjacent to each other and have one word line therebetween, is disposed at a higher level than the bottom surfaces of the active gate electrodes.

主权项

1. A semiconductor device comprising:
a substrate, and a field region disposed in the substrate and defining active regions of the substrate, and wherein the substrate has active trenches therein extending in and across the active regions, and the field region has field trenches therein, and gate trenches each are constituted by respective ones of the active and field trenches together; and word lines each occupying the gate trenches, respectively, and each extending longitudinally in a first direction across a plurality of the active regions, and wherein the word lines include active gate electrodes disposed within the active trenches, field gate electrodes disposed within the field trenches, and fin gate electrodes, each of the fin gate electrodes having front and back surfaces spaced from each other in the first direction and a bottommost surface extending between the front and back surfaces in the first direction, each of the fin gate electrodes having a center midway between the front and back surfaces thereof in the first direction, each of the active and field gate electrodes having a center in the first direction, and the centers of the fin gate electrodes being spaced in the first direction with respect to the centers of respective ones of the active and field gate electrodes, and each of the field gate electrodes has a bottommost surface disposed at a level higher than that of the bottommost surfaces of the fin gate electrodes.