Shallow trench isolation for a memory

摘要

In some embodiments, a gate structure with a spacer on its side may be used as a mask o form self-aligned trenches in microelectronic memory, such as a flash memory. A first portion of the gate structure may be used to form the mask, together with sidewall spacers, in some embodiments. Then, after forming the shallow trench isolations, a second portion of the gate structure may be added to form a mushroom shaped gate structure.

主权项

1. An apparatus comprising:
a substrate including two parallel trenches in the substrate defining an active area between the trenches; and a floating gate structure in the active area, the active area including an unetched portion of the substrate between a trench and an edge of the floating gate structure, wherein the unetched portion of the substrate is electrically inactive, and wherein the floating gate structure includes a first dielectric layer disposed between the active area and a lower gate layer, and further includes an upper gate layer disposed on the lower gate layer.