Bismuth thick films
Bismuth thick films are electrodeposited into hollows of a mold made from the lithographically patterned thick SU-8 photoresist (Ref). Annealing at close to the melting temperature recrystallizes the films and increases the mean free path of charge carriers. The observation of the huge magnetoresistance effect confirms the ballistic transport in the samples. We study the ballistic transport in Bi by using different shapes of the resulting structures, addressing both fundamental- and applied research questions. Electron focusing in a non-local geometry has been tried out, which can potentially result in a development of a magnetic sensor.
Figure. The magnetoresistance MR=[R(B)-R(0)]/R(0) for a 17 µm thick Bi film with 200 nm overlayer of gold. Annealing results in a huge increase of MR.
Supported by Stiftelse Olle Engkvist Byggmästare