Friday, May 19, 2006

US Patents 7045851 and 7045854 - Nanoparticles in FET gates

There are many approaches on the drawing boards and in laboratories attempting to find new nanoelectronics technology which may extend capabilities beyond the current MOSFET architectures. However, IBM and Hitachi, the respective patent owners, are both taking an intermediate approach for the time being as evidenced by these patents. Rather than trying to create an entirely new nanoelectronics technology, they are enhancing current FET structures with nanostructured material. Both these patents deal with the novel use of nanoparticulate matter in the gates of FET structures.

Quoting the '851 patent- "breaking up a continuous, conducting floating gate 106 into small bits of isolated conducting material can aid in overcoming some of the roadblocks to further scaling. The nanocrystal floating gate 156 has reduced capacitive coupling to the source 151/drain region 152, which leads to a smaller drain turn-on effect. In addition, the nanocrystal floating gate 106 should make the device less susceptible to stress-induced leakage current. That is, if an individual nanocrystal becomes shorted to the channel 154, other nanocrystals remain unaffected. In a standard floating gate device (e.g., such as device 100), any short to the channel 104 is disastrous because charge can no longer be maintained in the floating gate 106. "