Saturday, June 10, 2006

US Patent 7057245 - MEMS Transferred to Second Support

http://www.freepatentsonline.com/7057245.pdf

There has been some discussion about the US patent office's ability to handle nanotechnology patents. In my opinion, based on my experience as a Patent Examiner, graduate studies in nanotechnology, and a review of issuing nanotech patents, the quality of examination on average (with some exceptions as noted in the previous posting) is probably slightly better for nanotech patents than other patents. The reason for this is that usually the applicants for nanotech. patents are very knowledgeable of their field and provide the Examiner with a lot of background in the form of prior art submissions, etc. Also due to the popularization of nanotechnology in the press there is probably more pressure on the Examiner to do a thorough job for these applications.

Unfortunately, the same can not be said of microelectromechanical systems (MEMS) based inventions. Due to the variety of diverse applications to which these devices may be applied (sensors, rf switches, optical relays, displays, etc.) there is no centralized resource within the US patent office for Examiners to search for broad claims directed to these devices. In addition the inventors/applicants often may have expertise in their specific field to which they are applying MEMS (rf electronics, optics, etc) but have deficient knowledge of the numerous generic teachings related to MEMS. Often patent attorneys will write the broadest possible patent claims which may fall outside of the application of the main embodiment. All of the above factors result in numerous patents in the MEMS field being issued improperly.

Case in point is this patent US 7057245, in which pre-diced MEMS components are attached to a secondary substrate so that the actuation direction of the MEMS structure can be modified from the orientation with respect to a first substrate used for the initial manufacture. Claim 1 reads:

1. An array of lithographically fabricated MEMS devices comprising: a plurality of individual dies including at least one MEMS device, each die having been separated from adjacent dies on an original fabrication wafer, with each die of the plurality positioned on a second wafer, and affixed mechanically to said second wafer.


The Examiner apparently overlooked prior art patents such as http://www.freepatentsonline.com/5355577.pdf or
http://www.freepatentsonline.com/6291266.pdf
which employ techniques of fluidic self-assembly to assemble and adhere pre-diced MEMS components onto a secondary substrate.