Patent ID: 8598645

Claim:
An apparatus comprising: a substrate comprising at least one isolation trench and a periphery trench formed therein, the at least one isolation trench being a core trench; a liner oxide formed over a sidewall of the at least one isolation trench, the liner oxide comprising a first liner oxide formed over the sidewall of the core trench; a tunnel oxide formed over the substrate; an oxide material formed in the at least one isolation trench and including a portion extending above an upper surface of the tunnel oxide, the portion extending above the upper surface of the tunnel oxide forming a first mesa that extends over the liner oxide and has a width of at least 35 nm; a second liner oxide formed over a sidewall of the periphery trench, the first mesa extending over the first liner oxide formed over the sidewall of the core trench, a second mesa not extending over the second liner oxide formed over the sidewall of the periphery trench, and the second mesa being formed above the periphery trench and being narrower than the first mesa; a floating gate formed over the tunnel oxide and the first mesa, the floating gate extending across an entire length of an upper surface of the first mesa; and a control gate formed over the floating gate.