1. Instituto de Microelectrónica de Barcelona (IMB-CNM, CSIC), Carrer dels Tillers s/n, 08193 Bellaterra, Barcelona, Spain
2. Institute for Theoretical Physics, Georg-August-University, 37077 Göttingen, Germany
3. IBM Research − Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
4. SwissLitho AG, Technoparkstrasse 1, 8805 Zürich, Switzerland