| 摘要 |
PURPOSE:To prevent malfunction caused by alpha particles, by providing a resistance element and making the time constant given by the resistance and a capacitor greater than duration time of current generated by alpha rays. CONSTITUTION:A resistance element R is provided between a bit line BL and an MOS transistor Q for switching. Time constant given by the element R and a capacitor C for memory is made greater than the time of duration of current generated by alpha particles. Incidence of alpha particles generates many electron- positive hole pairs along their paths. Out of these pairs, electrons move toward n ''diffusion layer 12'' along the paths of alpha particles and lower potential of nodal point of circuit of the diffusion layer. At this time, potential of the line BL is lowered. However, the change is made slow by insertion of the resistance R. Movement of electrons is made in very short time, and the current is attenuated in a moment. Accordingly, by making the time constant large, malfunction due to incidence of alpha rays can be prevented. |
