Semiconductor device manufacturing method

摘要

There are provided the steps of forming a tunnel insulating film (2) on a semiconductor substrate (1), forming a first semiconductor film (3) constituting a lower portion of a floating gate (FG) on the tunnel insulating film (2), forming device isolation recesses (1a) by etching device isolation regions of the first semiconductor film (3), the tunnel insulating film (2), and the semiconductor substrate (1), forming an device isolation insulating film (7) in the device isolation recesses (1a) and on the first semiconductor film (3), removing the device isolation insulating film (7) from an upper surface of the first semiconductor film (3) and thinning the device isolation insulating film (7) on the device isolation recesses (1a), growing selectively a second semiconductor film (8) serving as an upper portion of the floating gate (FG) on the first semiconductor film (3) and growing the second semiconductor film (8) on the device isolation insulating film (7) to extend in the lateral direction, forming a dielectric film (9) on the floating gate (FG), and forming a conductive film (10) serving as a control gate on the dielectric film (CG).