| 摘要 |
PURPOSE:To contrive to make DRAM minute and to integrate it with high density by extending an access transistor onto an insulating film and by connecting a part of said transistor with a substrate and forming the part on a lead wiring composed of semiconductor film connected with a charge storage electrode. CONSTITUTION:N-type well 12 and P-type well 13 are formed from the substrate side on the main surface part of a low-concentration P-type silicon substrate 1 and a groove 2 is formed in the manner of reaching the N-type well 12. Inside the groove 2, a charge storage electrode 4 is buried via capacitance insulating film 3. The charge storage electrode 4 is connected with a lead wiring 5 composed of semiconductor film provided on the surface of the substrate. Also, the lead wiring 5 is directly connected onto the substrate. A gate electrode 11 is provided in the part of the lead wiring 5 connected directly onto the substrate and forming a single crystal via gate insulating film 15 and functions as an access transistor 9. The source region 8 and drain region 9 of the access transistor are formed within the lead wiring 5 and respectively connected onto the charge storage electrode 4 and a bit line 10. |
