Patent ID: 7151029

Claim:
A method comprising: depositing a first electrically conductive layer onto a substrate to form a first electrode; depositing a composite medium onto the first electrode; and depositing a second electrically conductive layer onto the composite medium to form a second electrode; wherein the composite medium comprises a layer of discrete charge trapping particles so that an electrical resistance measured across the first and second electrodes is selectively variable between a lower resistance R on and a higher resistance R off ; wherein R on is selected by applying a turn-on potential V on between the first and second electrodes; wherein R off is selected by applying a turn-off potential V off between the first and second electrodes; wherein the absolute value of the turn-off potential, |V off |, is greater than the absolute value of the turn-on potential, |V on |; and wherein the turn-off potential, V off and the turn-on potential, V on have the same polarity.