Scanning tunneling microscopy (STM) was applied to observe a surface oxide layer of titanium in air. When a sample bias voltage was set at —0.2 V, the STM tip penetrated into the surface oxide damaged the sample, while clear and stable images of the surface Ti02 layer were obtained under photoexcitation. The results were discussed in terms of enhanced electric conductivity of the oxide layer under photoexcitation.
- Photoexcitation effect
- Scanning tunneling microscopy
- Titanium dioxide