| 摘要 |
A semiconductor device comprises a silicon substrate having a laterally etched portion in an active region below a surface of the active region on side near device isolation film; an insulating film formed on the laterally etched portion of the silicon substrate; a conductive electrode formed on the insulating film, where an external voltage is applied to the conductive electrode to adjust a threshold voltage; and device isolation film on the conductive electrode. A semiconductor device comprises a silicon substrate (1) having a laterally etched portion in an active region below a surface of the active region on side near device isolation film (13); an insulating film formed on the laterally etched portion of the silicon substrate; a conductive electrode (11a) formed on the insulating film, where an external voltage is applied to the conductive electrode to adjust a threshold voltage; and device isolation film on the conductive electrode, where none or some pockets of vacant cavity is present between the device isolation film and the conductive electrode. An independent claim is also included for a method of manufacturing a semiconductor device having gates and junction regions, comprising forming a pad oxide film and a pad nitride film on a silicon substrate having a device isolation region and an active region; etching the pad oxide film, the pad nitride film, and the silicon substrate to form a trench in the device isolation region; forming an insulating film spacer on a trench sidewall including the etched pad oxide and nitride films; laterally etching a portion of the active region in the silicon substrate using the pad oxide film, the pad nitride film, and the insulating film spacer as etch barriers; removing the insulating film spacer; forming a conductive electrode on the surface adjoining the laterally etched portion in the active region and on the surface of the trench in the isolation region; and filling up the trench and the laterally etched portion with an oxide film to form a device isolation film, wherein none or some pockets of vacant cavity is present between the device isolation film and the conductive electrode. |
