Single-charge Circuits

Metallic devices containing tunnel junctions with sub-µm dimensions are fabricated by electron-beam-lithography in our clean room center.

The most important methods for the fabrication of devices, showing single charge effects (Single Electron Tunneling), are:

• Angle evaporation with shadow-masks
  
  • Standard shadow evaporation
  • Four-angle shadow evaporation to create very small islands
  • Shadow evaporation for refractory materials like niobium
    

• TEM-direct writing

• Nb trilayer-technique with Spin-on-Glass or CMP planarization