Patent ID: 6096624
Filing Date: 2000-08-01
Classification: H01L

Abstract:
A method for manufacturing Intel Type Flash EPROM (erasable programming read-only memory) (ETOX) cells using a self-aligned source etching process comprising the steps of:providing a substrate that has a plurality of gate stacks and a plurality of field oxide layers already formed thereon, each of the stack includes a tunnel oxide layer, a floating gate, a oxide/nitride/oxide layer and a controlling gate, wherein the controlling gates and the floating gates together constitute a plurality of gate terminals for a number of ETOX cells;forming a plurality of spacers on each side of the gate stack sidewalls and next to the gate stacks;forming a photomask over the substrate with a pattern exposing portions of the substrate and common source regions of the ETOX cells; andetching an exposed portion of the field oxide layer to expose the substrate, wherein the spacers remain exposed to this step of etching.