Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2402.07151 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866913467606237184 |
|---|---|
| author | Jangra, Vikas Kataria, Satender Lemme, Max C. |
| author_facet | Jangra, Vikas Kataria, Satender Lemme, Max C. |
| contents | Graphene has been extensively studied for a variety of electronic and optoelectronic applications. The reported contact resistance between metal and graphene, or rather its specific contact resistance (R{_C}), ranges from a few tens of Ω μm up to a few kΩ μm. Manufacturable solutions for defining ohmic contacts to graphene remain a subject of research. Here, we report a scalable method based on laser irradiation of graphene to reduce the R{_C} in nickel-contacted devices. A laser with a wavelength of λ = 532 nm is used to induce defects at the contact regions, which are monitored \textit{in-situ} using micro-Raman spectroscopy. Physical damage is observed using \textit{ex-situ} atomic force and scanning electron microscopy. The transfer line method (TLM) is used to extract R{_C} from back-gated graphene devices with and without laser treatment under ambient and vacuum conditions. A significant reduction in R{_C} is observed in devices where the contacts are laser irradiated, which scales with the laser power. The lowest R{_C} of about 250 Ω μm is obtained for the devices irradiated with a laser power of 20 mW, compared to 900 Ω μm for the untreated devices. The reduction is attributed to an increase in defect density, which leads to the formation of crystallite edges and in-plane dangling bonds that enhance the injection of charge carriers from the metal into the graphene. Our work suggests laser irradiation as a scalable technology for R{_C} reduction in graphene and potentially other two-dimensional materials. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2402_07151 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Reducing the metal-graphene contact resistance through laser-induced defects Jangra, Vikas Kataria, Satender Lemme, Max C. Applied Physics Graphene has been extensively studied for a variety of electronic and optoelectronic applications. The reported contact resistance between metal and graphene, or rather its specific contact resistance (R{_C}), ranges from a few tens of Ω μm up to a few kΩ μm. Manufacturable solutions for defining ohmic contacts to graphene remain a subject of research. Here, we report a scalable method based on laser irradiation of graphene to reduce the R{_C} in nickel-contacted devices. A laser with a wavelength of λ = 532 nm is used to induce defects at the contact regions, which are monitored \textit{in-situ} using micro-Raman spectroscopy. Physical damage is observed using \textit{ex-situ} atomic force and scanning electron microscopy. The transfer line method (TLM) is used to extract R{_C} from back-gated graphene devices with and without laser treatment under ambient and vacuum conditions. A significant reduction in R{_C} is observed in devices where the contacts are laser irradiated, which scales with the laser power. The lowest R{_C} of about 250 Ω μm is obtained for the devices irradiated with a laser power of 20 mW, compared to 900 Ω μm for the untreated devices. The reduction is attributed to an increase in defect density, which leads to the formation of crystallite edges and in-plane dangling bonds that enhance the injection of charge carriers from the metal into the graphene. Our work suggests laser irradiation as a scalable technology for R{_C} reduction in graphene and potentially other two-dimensional materials. |
| title | Reducing the metal-graphene contact resistance through laser-induced defects |
| topic | Applied Physics |
| url | https://arxiv.org/abs/2402.07151 |