Friday, May 01, 2009

US Patent 7525149 - Graded tunnel dielectric nanocrystal memory cell

This patent from Micron Technology teaches a new nanocrystal charge trapping memory cell using a graded SiC-GeC-SiC composition as a tunnel dielectric offering improved scalability characteristics over other memory cell structures found in flash and SONOS designs. Claim 1 reads:

1. A memory cell comprising:

a substrate having a plurality of implanted regions;

a tunnel dielectric formed over the substrate, the tunnel dielectric comprising a graded composite of silicon carbide and germanium carbide; and

a charge blocking layer formed over the tunnel dielectric, the charge blocking layer having a charge trapping layer comprised of nano-crystals.