Impact of surface treatments on the transport properties of germanium 2DHGs
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866914508234031104 |
|---|---|
| author | Sangwan, Nikunj Jutzi, Eric Olsen, Christian Vogel, Sarah Nigro, Arianna Zardo, Ilaria Hofmann, Andrea |
| author_facet | Sangwan, Nikunj Jutzi, Eric Olsen, Christian Vogel, Sarah Nigro, Arianna Zardo, Ilaria Hofmann, Andrea |
| contents | Holes in planar germanium (Ge) heterostructures show promise for quantum applications, particularly in superconducting and spin qubits, due to strong spin-orbit interaction, low effective mass, and absence of valley degeneracies. However, charge traps cause issues such as gate hysteresis and charge noise. This study examines the effect of surface treatments on the accumulation behaviour and transport properties of Ge-based two dimensional hole gases (2DHGs). Oxygen plasma treatment reduces conduction in a setting without applied top-gate voltage and improves the mobility and lowers the percolation density, while hydrofluoric acid (HF) etching provides no benefit. The results suggest that interface traps from the partially oxidised silicon (Si) cap pin the Fermi level, and that oxygen plasma reduces the trap density by fully oxidising the Si cap. Therefore, optimising surface treatments is crucial for minimising the charge traps and thereby enhancing the device performance. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2411_03995 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Impact of surface treatments on the transport properties of germanium 2DHGs Sangwan, Nikunj Jutzi, Eric Olsen, Christian Vogel, Sarah Nigro, Arianna Zardo, Ilaria Hofmann, Andrea Mesoscale and Nanoscale Physics Materials Science Quantum Physics Holes in planar germanium (Ge) heterostructures show promise for quantum applications, particularly in superconducting and spin qubits, due to strong spin-orbit interaction, low effective mass, and absence of valley degeneracies. However, charge traps cause issues such as gate hysteresis and charge noise. This study examines the effect of surface treatments on the accumulation behaviour and transport properties of Ge-based two dimensional hole gases (2DHGs). Oxygen plasma treatment reduces conduction in a setting without applied top-gate voltage and improves the mobility and lowers the percolation density, while hydrofluoric acid (HF) etching provides no benefit. The results suggest that interface traps from the partially oxidised silicon (Si) cap pin the Fermi level, and that oxygen plasma reduces the trap density by fully oxidising the Si cap. Therefore, optimising surface treatments is crucial for minimising the charge traps and thereby enhancing the device performance. |
| title | Impact of surface treatments on the transport properties of germanium 2DHGs |
| topic | Mesoscale and Nanoscale Physics Materials Science Quantum Physics |
| url | https://arxiv.org/abs/2411.03995 |