Mhamdi E.M.E.,Institute of Microengineering IMT |
Holovsky J.,Institute of Microengineering IMT |
Holovsky J.,ASCR Institute of Physics Prague |
Demaurex B.,Institute of Microengineering IMT |
And 2 more authors.
Applied Physics Letters | Year: 2014
Thin hydrogenated amorphous silicon (a-Si:H) films deposited on crystalline silicon (oSi) surfaces are sensitive probes for the bulk electronic properties of a-Si:H. Here, we use such samples during repeated low- Temperature annealing and visible-light soaking to investigate the long- Term stability of a-Si:H films. We observe that during annealing the electronic improvement of the interfaces follows stretched exponentials as long as hydrogen evolution in the films can be detected. Once such evolution is no longer observed, the electronic improvement occurs much faster. Based on these findings, we discuss how the reversibility of light-induced defects depends on (the lack of observable) hydrogen evolution. © 2014 AIP Publishing LLC.
Yoshikawa G.,Japan International Center for Materials Nanoarchitectonics |
Akiyama T.,Institute of Microengineering IMT |
Loizeau F.,Institute of Microengineering IMT |
Shiba K.,Japan International Center for Materials Nanoarchitectonics |
And 5 more authors.
Sensors (Switzerland) | Year: 2012
We present a new generation of piezoresistive nanomechanical Membrane-type Surface stress Sensor(MSS) chips, which consist of a two dimensional array of MSS on a single chip. The implementation of several optimization techniques in the design and microfabrication improved the piezoresistive sensitivity by 3~4 times compared to the first generation MSS chip, resulting in a sensitivity about ~100 times better than a standard cantilever-type sensor and a few times better than optical read-out methods in terms of experimental signal-to-noise ratio. Since the integrated piezoresistive read-out of the MSS can meet practical requirements, such as compactness and not requiring bulky and expensive peripheral devices, the MSS is a promising transducer for nanomechanical sensing in the rapidly growing application fields in medicine, biology, security, and the environment. Specifically, its system compactness due to the integrated piezoresistive sensing makes the MSS concept attractive for the instruments used in mobile applications. In addition, the MSS can operate in opaque liquids, such as blood, where optical read-out techniques cannot be applied. © 2012 by the authors; licensee MDPI, Basel, Switzerland.