14 DAY TRIAL // An international collaboration of scientists, coordinated by investigators at the US National Institute of Standards and Technology (NIST), announces the development of a new type of rugged thin-film membrane. The material could have significant applications in the field of medicine.
According to the research team, the membrane could be used to create sterilizable, flexible organic electronics, which could then be fashioned into soft pacemakers and similar medical implants.
The research team included members from the University of Tokyo, the Japan Science and Technology Agency, Princeton University, the Max Planck Institute for Solid State Research, Hiroshima University and Nippon Kayaku Co., Ltd.
The work was carried out at the NIST low-energy X-ray beam line, which is located at the National Synchrotron Light Source (NSLS) in Brookhaven, New York. The NSLS is based at the US Department of Energy's (DOE) Brookhaven National Laboratory (BNL).
Engineers say that the main advantage organic microelectronics have over silicon is that they do not feature a rigid, crystalline structure. Instead, the flexible polymeric materials have the potential to enable applications such as the creation of lightweight computer displays that can be bent and stretched.
One of the main issues with using organic electronics in medical applications is sterilization. The process needs to take place at high temperatures, where the devices tend to break down, especially in their gate insulation layer.
This particular layer has to be extremely thin, in order to maintain electrical integrity while heated, while at the same time holding down the operating voltage at a level that makes operations possible.
Usually, subjecting organic materials to heat leads to the development of pinholes within its structure. The new material solves this problem by self-assembling into “an ultrathin single layer of densely packed linear molecules that line up at a slight angle to the surface,” a NIST statement explains.
In the study, the team found that the new, self-assembled monolayer (SAM) can be as little as 2 nanometers thin. This is why the NSLS beam line was used. Determining the structure of such thin layers is very difficult using other research methods.
The technique the team used is called near-edge X-ray absorption fine-structure spectroscopy (NEXAFS). Through this approach, the international team developed the world's first sterilizable, flexible organic transistor.