US Patent 7932189 - Fabrication of silicon nanocrystal memory cell

http://www.freepatentsonline.com/7932189.html

Nanocrystal films can play an important role in enhancing the reliability of nanoscale floating gate memory cells. This patent from Freescale Semiconductor teaches a fabrication method for such films. Claim 1 reads:

1. A process of forming an electronic device comprising:

forming a first layer of discontinuous storage elements over a dielectric layer, wherein: the discontinuous storage elements have an average diameter of approximately 2 to approximately 20 nm; and

at least some of the discontinuous storage elements are silicon nanocrystals;

forming a second layer over the discontinuous storage elements and substantially all of the dielectric layer, wherein the second layer is a silicon layer having a thickness in a range of approximately 3 to approximately 9 nm;

oxidizing substantially all of the second layer; and

forming a gate electrode after oxidizing substantially all of the second layer, wherein the electronic device includes a memory cell comprising a set of the discontinuous storage elements and the gate electrode.