NONVOLATILE MEMORY DEVICES AND METHODS OF PROGRAMMING AND READING NONVOLATILE MEMORY DEVICES

In a method of programming a nonvolatile memory device, a program operation is performed on a selected memory cell coupled to a selected word line in response to a program command, a negative bias voltage is applied to the selected word line, a verification pass voltage is applied to an unselected word line after the negative bias voltage is applied to the selected word line, and a first program verification voltage, which is higher than the negative bias voltage and lower than a ground voltage, is applied to the selected word line.