| 摘要 |
A method and structure for manufacturing a high-density split gate memory cell, for a flash memory or EPROM, is described. Silicon islands are formed from a silicon substrate implanted with a first conductivity-imparting dopant. A first dielectric layer surrounds the vertical surfaces of the silicon islands, whereby the first dielectric layer is a gate oxide. A first conductive layer is formed over a portion of the vertical surfaces of the first dielectric layer, and acts as a floating gate for the high density split-gate memory cell. A source region is located in the silicon substrate, and is implanted with a second and opposite conductivity-imparting dopant to the first conductivity-imparting dopant, and surrounds the base of the silicon islands. A drain region is located in the top of the silicon islands, and is also implanted with a second and opposite conductivity-imparting dopant to the first conductivity-imparting dopant. A second dielectric layer is formed over the top and side surfaces of the floating gate, and acts as an interpoly dielectric. A second conductive layer is formed over that remaining portion of the vertical surfaces of the first dielectric layer not covered by the first conductive layer, and surrounds the second dielectric layer, whereby the second conductive layer is a control gate.
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