Impact of Defects on the Low-Field Electron Mobility in GaN-on-Si HEMTs
In this work, we investigate the field and temperature dependence of the electron mobility in aluminum-gallium-nitride/gallium-nitride (AlGaN/GaN) high electron mobility transistors (HEMTs) realized on GaN-on-silicon (Si) substrates. For this purpose we employ an extraction method to eliminate paras...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IEEE
2025-01-01
|
| Series: | IEEE Journal of the Electron Devices Society |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/11031174/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849425936947085312 |
|---|---|
| author | Ran Zhou D. J. Gravesteijn R. J. E. Hueting |
| author_facet | Ran Zhou D. J. Gravesteijn R. J. E. Hueting |
| author_sort | Ran Zhou |
| collection | DOAJ |
| description | In this work, we investigate the field and temperature dependence of the electron mobility in aluminum-gallium-nitride/gallium-nitride (AlGaN/GaN) high electron mobility transistors (HEMTs) realized on GaN-on-silicon (Si) substrates. For this purpose we employ an extraction method to eliminate parasitic and fringing effects. Our results show that especially at low fields the temperature dependence of the mobility, and consequently that of the specific on-resistance, is strongly affected by stress-induced charged dislocation scattering. For explaining the mobility behaviour at low fields, the subthreshold operation regime of the HEMTs has also been analyzed. An interface trap density at the AlGaN/GaN interface <inline-formula> <tex-math notation="LaTeX">$(N_{\textrm {it}})$ </tex-math></inline-formula> of <inline-formula> <tex-math notation="LaTeX">$\sim ~6.9\times 10^{10}$ </tex-math></inline-formula> cm−2 has been extracted independent of the temperature which is close to the extracted dislocation density from mobility measurements. This suggests that the relatively high dislocation density in the GaN layer, which is a consequence of the still imperfect buffer layer in the GaN-on-Si substrate that is used to accommodate the strain difference, has an impact on <inline-formula> <tex-math notation="LaTeX">$N_{\textrm {it}}$ </tex-math></inline-formula>, thus subthreshold swing, in addition to the mobility reduction. |
| format | Article |
| id | doaj-art-c9bf8e07a3874f249d94ed032ecdd8f5 |
| institution | Kabale University |
| issn | 2168-6734 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Journal of the Electron Devices Society |
| spelling | doaj-art-c9bf8e07a3874f249d94ed032ecdd8f52025-08-20T03:29:35ZengIEEEIEEE Journal of the Electron Devices Society2168-67342025-01-011351652310.1109/JEDS.2025.357726011031174Impact of Defects on the Low-Field Electron Mobility in GaN-on-Si HEMTsRan Zhou0https://orcid.org/0009-0008-6622-1857D. J. Gravesteijn1https://orcid.org/0000-0003-4628-1947R. J. E. Hueting2https://orcid.org/0000-0002-0773-8978MESA+ Institute, University of Twente, Enschede, The NetherlandsMESA+ Institute, University of Twente, Enschede, The NetherlandsMESA+ Institute, University of Twente, Enschede, The NetherlandsIn this work, we investigate the field and temperature dependence of the electron mobility in aluminum-gallium-nitride/gallium-nitride (AlGaN/GaN) high electron mobility transistors (HEMTs) realized on GaN-on-silicon (Si) substrates. For this purpose we employ an extraction method to eliminate parasitic and fringing effects. Our results show that especially at low fields the temperature dependence of the mobility, and consequently that of the specific on-resistance, is strongly affected by stress-induced charged dislocation scattering. For explaining the mobility behaviour at low fields, the subthreshold operation regime of the HEMTs has also been analyzed. An interface trap density at the AlGaN/GaN interface <inline-formula> <tex-math notation="LaTeX">$(N_{\textrm {it}})$ </tex-math></inline-formula> of <inline-formula> <tex-math notation="LaTeX">$\sim ~6.9\times 10^{10}$ </tex-math></inline-formula> cm−2 has been extracted independent of the temperature which is close to the extracted dislocation density from mobility measurements. This suggests that the relatively high dislocation density in the GaN layer, which is a consequence of the still imperfect buffer layer in the GaN-on-Si substrate that is used to accommodate the strain difference, has an impact on <inline-formula> <tex-math notation="LaTeX">$N_{\textrm {it}}$ </tex-math></inline-formula>, thus subthreshold swing, in addition to the mobility reduction.https://ieeexplore.ieee.org/document/11031174/High electron mobility transistorstwo-dimensional electron gasgallium-nitridemobilityinterface statesdislocations |
| spellingShingle | Ran Zhou D. J. Gravesteijn R. J. E. Hueting Impact of Defects on the Low-Field Electron Mobility in GaN-on-Si HEMTs IEEE Journal of the Electron Devices Society High electron mobility transistors two-dimensional electron gas gallium-nitride mobility interface states dislocations |
| title | Impact of Defects on the Low-Field Electron Mobility in GaN-on-Si HEMTs |
| title_full | Impact of Defects on the Low-Field Electron Mobility in GaN-on-Si HEMTs |
| title_fullStr | Impact of Defects on the Low-Field Electron Mobility in GaN-on-Si HEMTs |
| title_full_unstemmed | Impact of Defects on the Low-Field Electron Mobility in GaN-on-Si HEMTs |
| title_short | Impact of Defects on the Low-Field Electron Mobility in GaN-on-Si HEMTs |
| title_sort | impact of defects on the low field electron mobility in gan on si hemts |
| topic | High electron mobility transistors two-dimensional electron gas gallium-nitride mobility interface states dislocations |
| url | https://ieeexplore.ieee.org/document/11031174/ |
| work_keys_str_mv | AT ranzhou impactofdefectsonthelowfieldelectronmobilityinganonsihemts AT djgravesteijn impactofdefectsonthelowfieldelectronmobilityinganonsihemts AT rjehueting impactofdefectsonthelowfieldelectronmobilityinganonsihemts |