article
Submicron fabrication by local anodic oxidation of germanium thin films
Registro en:
1742-6588 (print), 1742-6596 (online)
10.1088/0957-4484/20/34/345301
Autor
Oliveira, Alexandre Barbosa de
Ribeiro, Gilberto Medeiros
Costa, Antonio Azevedo da
Resumen
Here we describe a lithography scheme based on the local anodic oxidation of germanium film by a scanning atomic force microscope in a humidity-controlled atmosphere. The oxidation kinetics of the Ge film were investigated by a tapping mode, in which a pulsed bias voltage was synchronized and applied with the resonance frequency of the cantilever, and by a contact mode, in which a continuous voltage was applied. In the tapping mode we clearly identified two regimes of oxidation as a function of the applied voltage: the trench width increased linearly during the vertical growth and increased exponentially during the lateral growth. Both regimes of growth were interpreted taking into consideration the Cabrera–Mott mechanism of oxidation
applied to the oxide/Ge interface. We also show the feasibility of the bottom-up fabrication process presented in this work by showing a Cu nanowire fabricated on top of a silicon substrate.