TRANSISTOR OF SEMICONDUCTOR DEVICE AND MATHOD FOR MANUFACTURING THE SAME

摘要

A transistor of a semiconductor device comprises: (i) stack type gate in which tunnel oxide film, floating gate, dielectric film and control gate are sequentially stacked on a semiconductor substrate; (ii) gate oxide film formed along the boundary of portion of bottom and side of floating gate; and (iii) floating nitride films that are buried at gaps between the gate oxide film formed on semiconductor substrate and the gate oxide film formed on floating gate. A transistor of a semiconductor device comprises: (a) a stack type gate in which a tunnel oxide film, a floating gate, a dielectric film and a control gate are sequentially stacked on a semiconductor substrate (200); (b) a gate oxide film that is formed on the semiconductor substrate below the floating gate with respect to the tunnel oxide film, where the gate oxide film is formed along the boundary of a portion of the bottom and side of the floating gate; and (c) floating nitride films (228) that are buried at gaps between the gate oxide film (226) formed on the semiconductor substrate and the gate oxide film formed along the boundary of a portion of the bottom and side of the floating gate. The floating nitride films serve as a trap center of a hot charge and store 1 bit charge. An independent claim is also included for a method of manufacturing a transistor of a semiconductor device, comprising: (1) forming a tunnel oxide film on a semiconductor substrate; (2) stacking a floating gate, a dielectric film, a control gate and a capping film on the tunnel oxide film and patterning the floating gate, the dielectric film, the control gate and the capping film to form a stack type gate, where the floating gate is partially patterned so that a predetermined thickness remains; (3) forming first spacers (220) on sidewalls of the capping film, the control gate, the dielectric film and the floating gate; (4) etching the remaining floating gate using the capping film and the first spacer as an etch mask; (5) growing an oxide film on the tunnel oxide film and at the side of the floating gate to form a thermal oxide film that is infiltrated into the bottom of the floating gate at a given depth; (6) removing the tunnel oxide film at the bottom of the thermal oxide film and the thermal oxide film; (7) forming gaps of a predetermined shape between a gate oxide film formed at the side and bottom of the floating gate and a gate oxide film formed on the semiconductor substrate, while growing a gate oxide film at the side and bottom of the exposed floating gate and on the semiconductor substrate; (8) depositing a nitride film on the semiconductor substrate on which the gate oxide films are grown to form floating nitride films to bury the gaps; and (9) forming second spacers (230) on sidewalls of the first spacers, the gate oxide film and the floating nitride film.