Monday, June 12, 2006

US Patent 7057881 - Nanofiber Capacitor

http://www.freepatentsonline.com/7057881.pdf

One of the simplest electronic structures is the capacitor. Basically this circuit element includes two electrodes separated by an insulating element and is useful for constructing electrical filters, phase shifters, sensors and for performing a variety of other functions for signal processing, detection, or related applications. In some cases large values of capacitances are necessary to achieve a certain function. This may be achieved in a variety of ways including increasing the area of the electrodes used to form the capacitors. However, creating larger electrodes is counterproductive to the development of smaller scale circuitry and thus a different solution is desirable. This patent suggests the use of nanofibers on the electrodes to increase the effective surface area of the capacitor. Claim 1 reads:

1. An electric capacitor, comprising at least a first electrode surface, which electrode surface comprises a plurality of nanofibers, wherein a density of the plurality of nanofibers ranges from about 0.11 nanofiber per square micron or less to at least about 1000 nanofibers per square micron, from about 1 nanofiber per square micron or less to at least about 500 nanofibers per square micron, from about 10 nanofibers per square micron or less to at least about 250 nanofibers per square micron, or from about 50 nanofibers per square micron or less to at least about 100 nanofibers per square micron.

One bizarre thing about this claim from a legal perspective is that typically when range within a range claims are presented it causes indefiniteness resulting in a 35 USC 112 2nd para. rejection (MPEP 2173.05c).