| 摘要 |
PURPOSE:To shorten the rewriting time largely by using tunnel currents in a rewritable nonvolatile semiconductor memory. CONSTITUTION:High voltage VPP is applied to gates for selective transistors TR100, 101 in order to rewrite information, and supply voltage VCC is applied to a source 119. VPP is applied to one of two metallic wirings 120, 121 and ground potential to the other in response to data to be written. When voltage VPP is applied to the wiring 120 and the wiring 121 is brought to ground potential, a control gate 116 is grounded, and high voltage is applied to an electrode 113, thus applying a high electric field to a thin oxide film, then discharging electrons to a substrate 110 from a floating gate 115 by a tunnel phenomenon. |
