Flash memory device and manufacture thereof

A method for manufacturing a flash memory device, comprising:

• providing a substrate;
• forming a plurality of sacrificial layers and a plurality of interval insulation layers on the substrate, with the sacrificial layers and the interval insulation layers stacking over each other alternately;
• forming a through-hole by etching the sacrificial layers and the interval insulation layers until an upper surface of the substrate is exposed;
• forming a channel structure in the through-hole, wherein the channel structure comprises, sequentially from inner to outer of the channel structure, a channel layer, a tunnel insulation layer wrapped around the channel layer, a charge capture layer wrapped around the tunnel insulation layer, and a blocking layer wrapped around the charge capture layer, wherein the channel layer comprises a first component substantially perpendicular to the upper surface of the substrate and a second component on the first component;
• forming a plurality of interval cavities by removing the sacrificial layers;
• forming a plurality of gate structures in the interval cavities, with a topmost gate structure wrapped around the second component of the channel layer;
• and
• forming a channel contact component contacting the second component of the channel layer, wherein the channel contact component and the second component of the channel layer form a Schottky contact.