US Patent 7288809 Flash memory with buried bit lines

A memory cell and a method of forming the same are described. The memory cell is formed on a substrate. The memory cell includes a floating gate that is formed at least in part within the substrate. A bit line region is formed within the substrate in proximity to the floating gate. Because of the configuration of the bit line and the floating gate, memory cells can be located closer to each other, increasing the density of memory cells in a memory array.