Memory unit, memory unit array and method of manufacturing the same

摘要

A memory unit includes a substrate, at least one charge storage element, at least one first recessed access element, and an isolation portion. The substrate has a surface and the first recessed access element is disposed in an active area of the substrate and extending from the surface into the substrate. The first recessed access element is electrically connected to the charge storage element and induces in the substrate a first depletion region. The isolation portion is adjacent to the active area and extending from the surface into the substrate. The isolation portion includes a trenched isolating barrier and a second recessed access element. The second recessed access element is disposed in the trenched isolating barrier and induces in the substrate a second depletion region merging with the first depletion region.

主权项

1. A memory unit comprising:
a substrate having a surface; at least one charge storage element; at least one first recessed access element disposed in an active area of the substrate and extending from the surface into the substrate, wherein the first recessed access element is a recessed access transistor, the first recessed access element is electrically connected to the charge storage element and, the first recessed access element is for inducing in the substrate a first depletion region; and an isolation portion adjacent to the active area and extending from the surface into the substrate, wherein the isolation portion includes a trenched isolating barrier and a second recessed access element, wherein the second recessed access element is disposed in the trenched isolating barrier for inducing in the substrate a second depletion region, and the trenched isolating barrier provides electrical insulation between the second recessed access element and the charge storage unit.