Patent ID: 8279664
Filing Date: 2012-10-02
Classification: G11C

Abstract:
1. A method of programming a phase change memory device, the method comprising: programming write data in a plurality of phase change memory cells by applying write pulses to each of the plurality of phase change memory cells; and verifying whether each of the phase change memory cells is programmed by applying verification pulses to each of the phase-change memory cells, wherein a number of applications for the verification pulses and corresponding intervals between the applications of the verification pulses are varied in accordance with a verification result for each of the phase-change memory cells, the verification pulses are not applied to a first phase change memory cell when the first phase change memory cell passes verification, the verification pulses are continuously applied to a second phase change memory cell until the second phase change memory cell passes verification within a defined number of applications for the verification pulses, and the verification pulses are applied to each of the phase-change memory cells at regular intervals.