| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a flash memory in which low voltage operation is enabled without thinning a gate insulating film and reliability is high. SOLUTION: In this flash memory, a trench 2 which is formed on the surface of a semiconductor substrate and has corners, a gate insulating film 3 formed on the surface in the trench, a floating gate 4 buried in the trench via the gate insulating film, and a control gate 5 which is formed being insulated from the floating gate are arranged on the semiconductor substrate 1. At the corners of the bottom of the trench, corners of the floating gate face corners of the semiconductor substrate via the above gate insulating film (portions in (2)), so that electrons are pulled out from the corners of the floating gate when a potential of the control gate is made low and a potential of the semiconductor substrate is made high.</p> |
