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arXiv · 2210.06870

Direct visualization and control of SrOx segregation on semiconducting Nb doped SrTiO3 (100) surface

Hyang Keun Yoo·Daniel Schwarz·Soren Ulstrup·Woojin Kim·Chris Jozwiak·Aaron Bostwick·Tae Won Noh·Eli Rotenberg·Young Jun Chang
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Abstract

We investigated how SrOx segregates on a Nb doped SrTiO3 (100) surface by in air annealing. Using atomic force and photoemission electron microscopes, we can directly visualize the morphology and the electronic phase changes with SrOx segregation. SrOx islands less than 2 micron meter in size and 1-5 unit cells thick nucleate first and grow in a labyrinth domain pattern. After prolonged annealing, SrOx forms a ~10 nm thick film. We show that the domain pattern can be controlled by introducing a surface miscut angle of SrTiO3. Additionally, the segregated SrOx has a lower work function, compared to that of SrTiO3. These results suggest that the control and tunability of SrOx segregation is applicable to the design of a new functional electronic devices in the semiconducting SrTiO3 based heterostructure.

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Hyang Keun Yoo, Daniel Schwarz, Soren Ulstrup, Woojin Kim, Chris Jozwiak, Aaron Bostwick, Tae Won Noh, Eli Rotenberg, Young Jun Chang. 2022-10-13. Direct visualization and control of SrOx segregation on semiconducting Nb doped SrTiO3 (100) surface. https://doi.org/10.1007/s40042-022-00471-5

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