US Patent 7444934 - Direct writing of nanoparticles using supercritical fluid

http://www.freepatentsonline.com/7444934.html

Supercritical fluids have properties between that of a liquid and gas with no surface tension due to no liquid/gas phase boundary. This patent from Micron teaches forming a nanoparticle solution using CO2 supercritical fluid suitable for an inkjet based maskless lithography. Claim 1 reads:

1. A method of direct writing a pattern layer of a microelectronic device formed on a substrate, the method comprising the acts of:

providing a substrate in a chamber;

providing a functional material comprising particles of a predetermined size;

reducing the predetermined size of the particles of the functional material to form nanometer-sized particles of the functional material;

providing a supercritical fluid in contact with the nanometer-sized particles to form a suspension solution; and

delivering the suspension solution to a surface of the substrate in the chamber to form a pattern layer of a microelectronic device on the surface of the substrate.