Temperature-Independent Current Dispersion in 0.15 μm AlGaN/GaN HEMTs for 5G Applications
Thanks to high-current densities and cutoff frequencies, short-channel length AlGaN/GaN HEMTs are a promising technology solution for implementing RF power amplifiers in 5G front-end modules. These devices, however, might suffer from current collapse due to trapping effects, leading to compressed ou...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-12-01
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| Series: | Micromachines |
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| Online Access: | https://www.mdpi.com/2072-666X/13/12/2244 |
| _version_ | 1797456244534935552 |
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| author | Nicolò Zagni Giovanni Verzellesi Alessandro Chini |
| author_facet | Nicolò Zagni Giovanni Verzellesi Alessandro Chini |
| author_sort | Nicolò Zagni |
| collection | DOAJ |
| description | Thanks to high-current densities and cutoff frequencies, short-channel length AlGaN/GaN HEMTs are a promising technology solution for implementing RF power amplifiers in 5G front-end modules. These devices, however, might suffer from current collapse due to trapping effects, leading to compressed output power. Here, we investigate the trap dynamic response in 0.15 μm GaN HEMTs by means of pulsed I-V characterization and drain current transients (DCTs). Pulsed I-V curves reveal an almost absent gate-lag but significant current collapse when pulsing both gate and drain voltages. The thermally activated Arrhenius process (with <i>E</i><sub>A</sub> ≈ 0.55 eV) observed during DCT measurements after a short trap-filling pulse (i.e., 1 μs) indicates that current collapse is induced by deep trap states associated with iron (Fe) doping present in the buffer. Interestingly, analogous DCT characterization carried out after a long trap-filling pulse (i.e., 100 s) revealed yet another process with time constants of about 1–2 s and which was approximately independent of temperature. We reproduced the experimentally observed results with two-dimensional device simulations by modeling the <i>T</i>-independent process as the charging of the interface between the passivation and the AlGaN barrier following electron injection from the gate. |
| first_indexed | 2024-03-09T16:05:26Z |
| format | Article |
| id | doaj.art-ad9373284c1446e9aaabe9d17ab022d3 |
| institution | Directory Open Access Journal |
| issn | 2072-666X |
| language | English |
| last_indexed | 2024-03-09T16:05:26Z |
| publishDate | 2022-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Micromachines |
| spelling | doaj.art-ad9373284c1446e9aaabe9d17ab022d32023-11-24T16:46:37ZengMDPI AGMicromachines2072-666X2022-12-011312224410.3390/mi13122244Temperature-Independent Current Dispersion in 0.15 μm AlGaN/GaN HEMTs for 5G ApplicationsNicolò Zagni0Giovanni Verzellesi1Alessandro Chini2Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, via P. Vivarelli 10, 41125 Modena, ItalyDepartment of Sciences and Methods for Engineering (DISMI) and EN&TECH Center, University of Modena and Reggio Emilia, via G. Amendola, 2, 42122 Reggio Emilia, ItalyDepartment of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, via P. Vivarelli 10, 41125 Modena, ItalyThanks to high-current densities and cutoff frequencies, short-channel length AlGaN/GaN HEMTs are a promising technology solution for implementing RF power amplifiers in 5G front-end modules. These devices, however, might suffer from current collapse due to trapping effects, leading to compressed output power. Here, we investigate the trap dynamic response in 0.15 μm GaN HEMTs by means of pulsed I-V characterization and drain current transients (DCTs). Pulsed I-V curves reveal an almost absent gate-lag but significant current collapse when pulsing both gate and drain voltages. The thermally activated Arrhenius process (with <i>E</i><sub>A</sub> ≈ 0.55 eV) observed during DCT measurements after a short trap-filling pulse (i.e., 1 μs) indicates that current collapse is induced by deep trap states associated with iron (Fe) doping present in the buffer. Interestingly, analogous DCT characterization carried out after a long trap-filling pulse (i.e., 100 s) revealed yet another process with time constants of about 1–2 s and which was approximately independent of temperature. We reproduced the experimentally observed results with two-dimensional device simulations by modeling the <i>T</i>-independent process as the charging of the interface between the passivation and the AlGaN barrier following electron injection from the gate.https://www.mdpi.com/2072-666X/13/12/2244GaN HEMTs5Gcurrent collapseT-independent processFe dopingTCAD simulations |
| spellingShingle | Nicolò Zagni Giovanni Verzellesi Alessandro Chini Temperature-Independent Current Dispersion in 0.15 μm AlGaN/GaN HEMTs for 5G Applications Micromachines GaN HEMTs 5G current collapse T-independent process Fe doping TCAD simulations |
| title | Temperature-Independent Current Dispersion in 0.15 μm AlGaN/GaN HEMTs for 5G Applications |
| title_full | Temperature-Independent Current Dispersion in 0.15 μm AlGaN/GaN HEMTs for 5G Applications |
| title_fullStr | Temperature-Independent Current Dispersion in 0.15 μm AlGaN/GaN HEMTs for 5G Applications |
| title_full_unstemmed | Temperature-Independent Current Dispersion in 0.15 μm AlGaN/GaN HEMTs for 5G Applications |
| title_short | Temperature-Independent Current Dispersion in 0.15 μm AlGaN/GaN HEMTs for 5G Applications |
| title_sort | temperature independent current dispersion in 0 15 μm algan gan hemts for 5g applications |
| topic | GaN HEMTs 5G current collapse T-independent process Fe doping TCAD simulations |
| url | https://www.mdpi.com/2072-666X/13/12/2244 |
| work_keys_str_mv | AT nicolozagni temperatureindependentcurrentdispersionin015mmalganganhemtsfor5gapplications AT giovanniverzellesi temperatureindependentcurrentdispersionin015mmalganganhemtsfor5gapplications AT alessandrochini temperatureindependentcurrentdispersionin015mmalganganhemtsfor5gapplications |