Patent ID: 8059450

Claim:
A write verify method for resistance random access memory (RRAM), the method comprising: applying a reset operation voltage pulse across a RRAM cell, the reset operation voltage pulse changing a resistance of the RRAM cell from a low resistance state to a high resistance state, the high resistance state having a range of resistance values, the reset operation voltage pulse having a first polarity; applying a forward resetting voltage pulse across the RRAM cell if any of a range of high resistance state resistance values is less than a selected lower resistance limit value, the forward resetting voltage pulse having the first polarity, repeating the applying one or more forward resetting voltage pulses step until all of the range of high resistance state resistance values are greater than the lower resistance limit value; and applying a reverse resetting voltage pulse across the RRAM cell if any of the range of high resistance state resistance values is greater than a selected upper resistance limit value, the reverse resetting voltage pulse having a second polarity being opposite the first polarity, repeating the applying one or more reverse resetting voltage pulses step until all of the range of high resistance state resistance values are less than the upper resistance limit value.