| 摘要 |
A dynamic random access memory unit includes a substrate having a trench disposed therein, a self-aligned trench isolation structure formed in the bottom portion of the trench, and a first trenched gate formed in the bottom portion of the trench and above the self-aligned trench isolation structure. The substrate includes at least one pillar-shaped active body having a drain region, a body region atop the drain region, and a source region atop the body region. The first trenched gate includes a first spacer formed on the side-wall in the bottom portion of the trench to selectively cover and surround the portion of the side-wall in the trench that comprises the drain region, such for defining the width of the self-aligned trench isolation structure. |
| 主权项 |
1. A dynamic random access memory unit, comprising:
a substrate, including at least one pillar-shaped active body and having a trench disposed in the substrate,
wherein the pillar-shaped active body has a drain region of a first conductivity type, a body region of a second conductivity type opposite to the first conductivity type, and a source region of the first conductivity type,
wherein the body region is arranged atop the drain region and the source region is arranged atop the body region; a self-aligned trench isolation structure, formed in the bottom portion of the trench; and a first trenched gate, formed in the bottom portion of the trench and above the self-aligned trench isolation structure,
wherein the first trenched gate includes a first spacer,
wherein the first spacer is formed on the side-wall in the bottom portion of the trench to selectively cover and surround the portion of the side-wall in the trench that comprises the drain region, such for defining the width of the self-aligned trench isolation structure. |
