US Patent 7688570 - Nanotube enhanced silicon capacitor

http://www.freepatentsonline.com/7688570.html

Dynamic random access memory (DRAM) is a form of semiconductor memory which uses capacitor structures to store data. However, the scaling of DRAM reduces the capacitance values making it difficult to provide reliable storage. This patent from Hynix Semiconductor teaches using nanotubes in the capacitor structure to increase the surface area and capacitance of DRAM memory cells. Claim 1 reads:

1. A capacitor, comprising:

a lower electrode including a patterned conductive layer and a plurality of nanotubes formed on the patterned conductive layer without using a catalytic layer;

a dielectric layer formed on the lower electrode; and

an upper electrode formed on the dielectric layer, wherein the patterned conductive layer is formed of a silicon layer.