Joined: 03 Oct 2005
|Posted: Mon Feb 27, 2006 3:39 pm Post subject: NEC Develop the World's Smallest Fiber-Optic Electric Field
|NEC Corporation Uses a Nanotechnology Process to Develop the World's Smallest Fiber-Optic Electric Field
NEC Corporation today announced the successful development of the world's smallest fiber-optic electric field probe, enabled through the adoption of a nanotechnology process. The newly developed probe consists of an optical fiber and an electro-optical film that is formed at its edge, which acts as a field sensor. As its lateral size of approximately 125 m is equivalent to that of the diameter of an optical fiber, the probe can be inserted into narrow spaces such as the crevice between a ball grid array (BGA) LSI package and a printed circuit board (200 - 300 m), enabling evaluation of the electrical characteristics of high-density packaged electronic circuits on printed circuit boards (PCBs). It can therefore be utilized to create electrical designs for high-density electronic packages toward the realization of low-noise/low-electromagnetic interference (EMI) level circuits.
The new probe was created based on a nanotechnology process referred to as aerosol deposition (AD), which was developed by the National Institute of Advanced Industrial Science and Technology (AIST), Japan. This process involves a recently developed ceramics film formation technology, which can directly deposit complex oxide films that consist of nano-particles on any kind of substrate material. By adopting the AD method for electro-optical film deposition, which consists of the formation of the electric field sensor onto an optical fiber edge surface, for the first time NEC was able to develop the world's first film processing techniques for precise sensing of electric fields.
The main features of the new probe are as follows:
1. Measurement of the electrical characteristics of high-density LSI packages has been enabled by successfully reducing the probe's sensor size to less than half of that of the smallest conventional fiber-optic electric field probes. Its lateral size of approximately 125 m is equivalent to that of the diameter of an optical fiber.
2. Detection of electrical signals in devices being tested is achieved by converting an electrical signal to an optical signal in the electro-optical 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 being test is undisturbed, resulting in the improvement of measurement accuracy.
3. Development of a highly-sensitive probe owing to the formation of a world-leading electro-optical film, lead zirconate titanate (PZT) film, on the edge of the fiber. This structure consists of the dense agglomeration of small particles, whose size is at a level of that of several tens of nanometers, resulting in both high transparency and large electro-optical conversion efficiency.
In recent years, the issue of electromagnetic noise in electronic equipment has become more serious due to an increase in the operation speed of electronic equipment and packaging density of electronic devices. In order to combat this, it is important to evaluate the electrical characteristics of LSIs that are mounted on PCBs (not the evaluation of unpackaged LSIs) and reflect the obtained results on the circuit design. However, conventional probes can not be used with today's very small, high density LSI packages as their size is too large to measure electrical signals or noise in microscopic regions such as the crevice between a BGA package and a printed circuit board.
In order to respond to these needs, NEC has been developing a probe that is capable of measuring microscopic regions on PCBs with high density LSI packages. Now, with the cooperation of AIST, it has succeeded in the successful development of a microscale electric field probe consisting of an optical fiber with a diameter of approximately 125 m and an electro-optical film, which is formed at the edge of the fiber. Realized utilizing a nanotechnology process, AD, this probe boasts the world's smallest electro-optical sensor.
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 (SiP). It contributes to the creation of optimal design as increased information vital to this can be obtained from timely circuit performance evaluation, failure diagnosis, production inspection and design checks.
NEC is certain that this development will contribute to the realization of reduced time to market, optimal package structure and enhanced reliability etc. Going forward, NEC will continue to advance this research toward the improvement of the sensitivity and the measurable frequency band of the probe with the aim of achieving practical use by the end of March, 2007.
This research was partially supported by a New Energy and Industrial Technology Development Organization (NEDO) project, Nano Structure Forming for Advanced Ceramic Integration Technology, within the Japan Nanotechnology Program, and will be exhibited at the International Nanotechnology Exhibition & Conference, which is being held at Tokyo Big Sight, Japan from February 21 to 23, 2006.
Source: NEC Corporation.
This story was posted on 22 February 2006.