US Patent 7679946 - Mem-resistor arrays with tunnel junctions

http://www.freepatentsonline.com/7679946.html

Memory resistors are nanoscale resistance switches offering a new form of non-volatile memory. One issue with mem-resistor arrays is leakage current "sneak paths" which reduce the efficiency of operation. This patent from Funai Electric teaches using tunnel junctions to avoid these sneak paths. Claim 1 reads:

1. A memory element array comprising

a plurality of memory elements arranged in an array,

wherein the memory elements are switching elements each including a gap of nanometer order in which a switching phenomenon of resistance is caused by applying a predetermined voltage between electrodes, and

the memory element array is provided with tunnel elements respectively connected to the switching elements in series, each of the tunnel elements preventing generation of a sneak path current flowing to another switching element at a time of applying the predetermined voltage.

It is notable that a similar memristor memory array with tunnel junctions was earlier suggested in US Patent 7038935 using a tunnel diode or MIM tunnel junction.