Investigation of significantly high barrier height in Cu/GaN Schottky diode
Current-voltage (I-V) measurements combined with analytical calculations have been used to explain mechanisms for forward-bias current flow in Copper (Cu) Schottky diodes fabricated on Gallium Nitride (GaN) epitaxial films. An ideality factor of 1.7 was found at room temperature (RT), which indicate...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2016-01-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/1.4939936 |
| _version_ | 1828180285356769280 |
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| author | Manjari Garg Ashutosh Kumar S. Nagarajan M. Sopanen R. Singh |
| author_facet | Manjari Garg Ashutosh Kumar S. Nagarajan M. Sopanen R. Singh |
| author_sort | Manjari Garg |
| collection | DOAJ |
| description | Current-voltage (I-V) measurements combined with analytical calculations have been used to explain mechanisms for forward-bias current flow in Copper (Cu) Schottky diodes fabricated on Gallium Nitride (GaN) epitaxial films. An ideality factor of 1.7 was found at room temperature (RT), which indicated deviation from thermionic emission (TE) mechanism for current flow in the Schottky diode. Instead the current transport was better explained using the thermionic field-emission (TFE) mechanism. A high barrier height of 1.19 eV was obtained at room temperature. X-ray photoelectron spectroscopy (XPS) was used to investigate the plausible reason for observing Schottky barrier height (SBH) that is significantly higher than as predicted by the Schottky-Mott model for Cu/GaN diodes. XPS measurements revealed the presence of an ultrathin cuprous oxide (Cu2O) layer at the interface between Cu and GaN. With Cu2O acting as a degenerate p-type semiconductor with high work function of 5.36 eV, a high barrier height of 1.19 eV is obtained for the Cu/Cu2O/GaN Schottky diode. Moreover, the ideality factor and barrier height were found to be temperature dependent, implying spatial inhomogeneity of barrier height at the metal semiconductor interface. |
| first_indexed | 2024-04-12T05:42:58Z |
| format | Article |
| id | doaj.art-4c3a8fead54e4350a22893993961b875 |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-04-12T05:42:58Z |
| publishDate | 2016-01-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-4c3a8fead54e4350a22893993961b8752022-12-22T03:45:32ZengAIP Publishing LLCAIP Advances2158-32262016-01-0161015206015206-710.1063/1.4939936025601ADVInvestigation of significantly high barrier height in Cu/GaN Schottky diodeManjari Garg0Ashutosh Kumar1S. Nagarajan2M. Sopanen3R. Singh4Department of Physics, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi-110016, IndiaDepartment of Physics, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi-110016, IndiaDepartment of Micro and Nanosciences, Aalto University, P.O. Box 13500, FI-00076, Aalto, FinlandDepartment of Micro and Nanosciences, Aalto University, P.O. Box 13500, FI-00076, Aalto, FinlandDepartment of Physics, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi-110016, IndiaCurrent-voltage (I-V) measurements combined with analytical calculations have been used to explain mechanisms for forward-bias current flow in Copper (Cu) Schottky diodes fabricated on Gallium Nitride (GaN) epitaxial films. An ideality factor of 1.7 was found at room temperature (RT), which indicated deviation from thermionic emission (TE) mechanism for current flow in the Schottky diode. Instead the current transport was better explained using the thermionic field-emission (TFE) mechanism. A high barrier height of 1.19 eV was obtained at room temperature. X-ray photoelectron spectroscopy (XPS) was used to investigate the plausible reason for observing Schottky barrier height (SBH) that is significantly higher than as predicted by the Schottky-Mott model for Cu/GaN diodes. XPS measurements revealed the presence of an ultrathin cuprous oxide (Cu2O) layer at the interface between Cu and GaN. With Cu2O acting as a degenerate p-type semiconductor with high work function of 5.36 eV, a high barrier height of 1.19 eV is obtained for the Cu/Cu2O/GaN Schottky diode. Moreover, the ideality factor and barrier height were found to be temperature dependent, implying spatial inhomogeneity of barrier height at the metal semiconductor interface.http://dx.doi.org/10.1063/1.4939936 |
| spellingShingle | Manjari Garg Ashutosh Kumar S. Nagarajan M. Sopanen R. Singh Investigation of significantly high barrier height in Cu/GaN Schottky diode AIP Advances |
| title | Investigation of significantly high barrier height in Cu/GaN Schottky diode |
| title_full | Investigation of significantly high barrier height in Cu/GaN Schottky diode |
| title_fullStr | Investigation of significantly high barrier height in Cu/GaN Schottky diode |
| title_full_unstemmed | Investigation of significantly high barrier height in Cu/GaN Schottky diode |
| title_short | Investigation of significantly high barrier height in Cu/GaN Schottky diode |
| title_sort | investigation of significantly high barrier height in cu gan schottky diode |
| url | http://dx.doi.org/10.1063/1.4939936 |
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