Institute of Microtechnology, University of Neuchâtel, Rue de Tivoli 28, CH-2003 Neuchâtel, Switzerland;Institute of Microtechnology, University of Neuchâtel, Rue de Tivoli 28, CH-2003 Neuchâtel, Switzerland;Centre Suisse d'Electronique et de Microtechnique SA, Rue de la Maladière 71, CH-2007 Neuchâtel, Switzerland;Institute of Microtechnology, University of Neuchâtel, Rue de Tivoli 28, CH-2003 Neuchâtel, Switzerland