| 摘要 |
PURPOSE:To facilitate the wiring of information in a read-only memory device by emitting electron beam to a floating gate, thereby injecting electrons thereto. CONSTITUTION:Electron beam 8 is emitted to the gate of an MOSFET having a silicon substrate 1, source and drain regions 2, 3 of reversely conductive type to the substrate 1, gate oxidized films 4, 6, a floating gate 5, and a control gate 7. The diffusion of the electrons thus emitted depends upon the accelerating voltage of the electron beam, it is necessary to sufficiently increase the accelerating voltage to large value so as to store the electron in the floating gate 5, but if it is excessively large, the electrons reach the substrate 1, thereby damaging the substrate 1. When the control gate 7 is accordingly grounded, the incident electrons are not stored in the gate 7, but are passed through the film 6 to be stored in the gate 5. |
