Thursday, April 05, 2012

US Patent 8148708 - Memresistor with CNT selection diode

In ReRAM devices the problem of current sneak paths limits the size of memory cell arrays. There have been suggestions of using metal oxide materials to improve non-linearity and avoid sneak paths but these materials reduce current density. This patent from Hynix Semiconductor teaches using carbon nanotubes as an alternative to produce rectifying characteristics without reducing current density. Claim 1 reads:

1. A resistive memory cell, comprising:

a first conductive line on a substrate;

a selection diode comprising a vertical nanotube and being arranged over the first conductive line;

a resistive element including a resistive layer arranged over the selection diode; and

a second conductive line arranged over the resistive element;

wherein the vertical nanotube includes a carbon nanotube.