| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a phase change memory device and a method for reading the device. <P>SOLUTION: A nonvolatile semiconductor memory device comprises: a phase change memory cell array 110 including a plurality of word lines WL, a plurality of bit lines BL, and a plurality of phase change memory cells (e.g., phase change memory cells 111), wherein each phase change memory cell includes a phase change resistance element and a diode connected in series, between one of the plurality of word lines and one of the plurality of bit lines; a sensing node NSA selectively connected to one bit line of the phase change memory cell array; a booster circuit for generating a boosting voltage VSA higher than an internal power supply voltage; a precharging and biasing circuit 175 driven by the boosting voltage and for precharging and biasing the sensing node; and a sensing amplifier connected to the sensing node. In this case, the booster voltage is made the same as or higher than the sum of the internal power supply voltage and the threshold voltage of the diode. <P>COPYRIGHT: (C)2007,JPO&INPIT |
