TOKYO, Feb. 21, 2006 -- NEC said today it used a nanotechnology process to develop what it claims is the world's smallest fiber-optic electric field probe. The probe is comprised of an optical fiber with an electro-optical film along its edge that acts as a field sensor. NEC said the probe, which is 126 µms in diameter -- about the size of an optical fiber -- can be inserted into narrow spaces such as the crevice between a ball grid array LSI package and a printed circuit board (200 to 300 µm) to enable evaluation of the electrical characteristics of high-density packaged electronic circuits. It can thus be used to create electrical designs for high-density electronic packages in developing low-noise/low-electromagnetic interference (EMI) level circuits, the company said. The new probe was created with a nanotechnology process called aerosol deposition, developed by the National Institute of Advanced Industrial Science and Technology in Japan. The process involves a ceramics film formation technology that can directly deposit complex oxide films that consist of nanoparticles on any kind of substrate material, NEC said in a statment. Detection of electrical signals in devices being tested is achieved by converting an electrical signal to an optical signal in the electro-optical lead zirconate titanate (PZT) film. Since the signal is sent by an optical fiber, a wave guide that does not contain metallic parts, the electromagnetic field surrounding the device is undisturbed, resulting in better measurement accuracy. The film is made of a dense agglomeration of particles only several tens of nanometers big. "The development of this tiny probe signifies a breakthrough in the creation of optimal package design, as it enables evaluation of electrical characteristics in packaging regions that could never before be reached, such as near the solder ball of a BGA package or the space among different chips in a system-in-package," NEC said. The company said it will conduct further research to improve the sensitivity and measurable frequency band of the probe. Its research was supported in part by a New Energy and Industrial Technology Development Organization project, Nano Structure Forming for Advanced Ceramic Integration Technology, within the Japan Nanotechnology Program. The device will be exhibited at the International Nanotechnology Exhibition & Conference being held this week in Tokyo. For more information, visit: www.nec.com