Semiconductor memory device and fabrication method thereof
AssigneeUnited Microelectronics Corp.
InventorsLiang Yi, Zhiguo Li, Xiaojuan Gao, Chi Ren
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Abstract
A semiconductor memory device includes a substrate; a source diffusion region in the substrate; a pair of floating gates disposed on opposite of the source diffusion region; a first dielectric cap layer disposed directly on each of the floating gates; an erase gate disposed on the source diffusion region and partially overlapping an upper inner corner of each of the floating gates; a second dielectric cap layer disposed on the erase gate and the first dielectric cap layer; a select gate disposed on a sidewall of the first dielectric cap layer; and a drain diffusion region disposed in the substrate and adjacent to the select gate.
Claims11
A semiconductor memory device, comprising:
- a substrate;
- a source diffusion region in the substrate;
- a pair of floating gates disposed on opposite of the source diffusion region;
- a first dielectric cap layer disposed directly on each of the floating gates, wherein the first dielectric cap layer has a curved surface;
- an erase gate disposed on the source diffusion region and partially overlapping an upper inner corner of each of the floating gates, wherein the erase gate has a T shaped profile comprising a horizontal upper portion and a vertical lower portion connecting to the horizontal upper portion, wherein the horizontal upper portion is in direct contact with a lower part of the curved surface of the first dielectric cap layer;
- a second dielectric cap layer disposed on the erase gate and the first dielectric cap layer;
- a select gate disposed on a sidewall of the first dielectric cap layer;
- and
- a drain diffusion region disposed in the substrate and adjacent to the select gate.
Dependencies are inferred from the claim text.