MEHTODS OF FORMING NON-VOLATILE MEMORY DEVICE HAVING FLOATING GATE

摘要

A method for forming a nonvolatile memory device having a floating gate is provided to prevent the damage of the floating gate due to a trench etching process by forming a trench using a spacer made of a trap-free insulating material. A tunnel insulating layer(102a), a first floating gate layer(104a) and a hard mask layer are sequentially formed on a substrate(100). A first opening for exposing the tunnel insulating layer to the outside is formed by patterning selectively the first floating gate layer and the hard mask layer. A spacer layer is formed along an upper surface of the resultant structure. The spacer layer is made of a trap-free insulating material. A spacer(110a') is formed at both sidewalls of the first opening by performing an anisotropic etching process on the spacer layer and the tunnel insulating layer until the substrate is exposed to the outside. A trench(112) for defining an active region is formed by etching the exposed portion of the substrate. An isolation pattern(114') for filling the trench and the first opening is formed thereon.