Combined Implications of UV/O<sub>3</sub> Interface Modulation with HfSiO<sub>X</sub> Surface Passivation on AlGaN/AlN/GaN MOS-HEMT
Surface passivation is critically important to improve the current collapse and the overall device performance in metal-oxide semiconductor high-electron mobility transistors (MOS-HEMTs) and, thus, their reliability. In this paper, we demonstrate the surface passivation effects in AlGaN/AlN/GaN-base...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-01-01
|
| Series: | Crystals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4352/11/2/136 |
| _version_ | 1797406333687824384 |
|---|---|
| author | Soumen Mazumder Ssu-Hsien Li Zhan-Gao Wu Yeong-Her Wang |
| author_facet | Soumen Mazumder Ssu-Hsien Li Zhan-Gao Wu Yeong-Her Wang |
| author_sort | Soumen Mazumder |
| collection | DOAJ |
| description | Surface passivation is critically important to improve the current collapse and the overall device performance in metal-oxide semiconductor high-electron mobility transistors (MOS-HEMTs) and, thus, their reliability. In this paper, we demonstrate the surface passivation effects in AlGaN/AlN/GaN-based MOS-HEMTs using ultraviolet-ozone (UV/O<sub>3</sub>) plasma treatment prior to SiO<sub>2</sub> -gate dielectric deposition. X-ray photoelectron spectroscopy (XPS) was used to verify the improved passivation of the GaN surface. The threshold voltage (V<sub>TH</sub>) of the MOS-HEMT was shifted towards positive due to the band bending at the SiO<sub>2</sub>/GaN interface by UV/O<sub>3</sub> surface treatment. In addition, the device performance, especially the current collapse, hysteresis, and 1/f characteristics, was further significantly improved with an additional 15 nm thick hafnium silicate (HfSiO<sub>X</sub>) passivation layer after the gate metallization. Due to combined effects of the UV/O<sub>3</sub> plasma treatment and HfSiO<sub>X</sub> surface passivation, the magnitude of the interface trap density was effectively reduced, which further improved the current collapse significantly in SiO<sub>2</sub>-MOS-HEMT to 0.6% from 10%. The UV/O<sub>3</sub>-surface-modified, HfSiO<sub>X</sub>-passivated MOS-HEMT exhibited a decent performance, with I<sub>DMAX</sub> of 655 mA/mm, G<sub>MMAX</sub> of 116 mS/mm, higher I<sub>ON</sub>/I<sub>OFF</sub> ratio of approximately <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mrow><mn>10</mn></mrow><mn>7</mn></msup></mrow></semantics></math></inline-formula>, and subthreshold swing of 85 mV/dec with significantly reduced gate leakage current (I<sub>G</sub>) of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>9.1</mn><mo> </mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>10</mn></mrow></msup></mrow></semantics></math></inline-formula> A/mm. |
| first_indexed | 2024-03-09T03:23:56Z |
| format | Article |
| id | doaj.art-dad08e609d5b44eb837230916cbd8772 |
| institution | Directory Open Access Journal |
| issn | 2073-4352 |
| language | English |
| last_indexed | 2024-03-09T03:23:56Z |
| publishDate | 2021-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Crystals |
| spelling | doaj.art-dad08e609d5b44eb837230916cbd87722023-12-03T15:05:11ZengMDPI AGCrystals2073-43522021-01-0111213610.3390/cryst11020136Combined Implications of UV/O<sub>3</sub> Interface Modulation with HfSiO<sub>X</sub> Surface Passivation on AlGaN/AlN/GaN MOS-HEMTSoumen Mazumder0Ssu-Hsien Li1Zhan-Gao Wu2Yeong-Her Wang3Department of Electrical Engineering, Institute of Microelectronics, National Cheng Kung University, Tainan 701, TaiwanDepartment of Electrical Engineering, Institute of Microelectronics, National Cheng Kung University, Tainan 701, TaiwanDepartment of Electrical Engineering, Institute of Microelectronics, National Cheng Kung University, Tainan 701, TaiwanDepartment of Electrical Engineering, Institute of Microelectronics, National Cheng Kung University, Tainan 701, TaiwanSurface passivation is critically important to improve the current collapse and the overall device performance in metal-oxide semiconductor high-electron mobility transistors (MOS-HEMTs) and, thus, their reliability. In this paper, we demonstrate the surface passivation effects in AlGaN/AlN/GaN-based MOS-HEMTs using ultraviolet-ozone (UV/O<sub>3</sub>) plasma treatment prior to SiO<sub>2</sub> -gate dielectric deposition. X-ray photoelectron spectroscopy (XPS) was used to verify the improved passivation of the GaN surface. The threshold voltage (V<sub>TH</sub>) of the MOS-HEMT was shifted towards positive due to the band bending at the SiO<sub>2</sub>/GaN interface by UV/O<sub>3</sub> surface treatment. In addition, the device performance, especially the current collapse, hysteresis, and 1/f characteristics, was further significantly improved with an additional 15 nm thick hafnium silicate (HfSiO<sub>X</sub>) passivation layer after the gate metallization. Due to combined effects of the UV/O<sub>3</sub> plasma treatment and HfSiO<sub>X</sub> surface passivation, the magnitude of the interface trap density was effectively reduced, which further improved the current collapse significantly in SiO<sub>2</sub>-MOS-HEMT to 0.6% from 10%. The UV/O<sub>3</sub>-surface-modified, HfSiO<sub>X</sub>-passivated MOS-HEMT exhibited a decent performance, with I<sub>DMAX</sub> of 655 mA/mm, G<sub>MMAX</sub> of 116 mS/mm, higher I<sub>ON</sub>/I<sub>OFF</sub> ratio of approximately <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mrow><mn>10</mn></mrow><mn>7</mn></msup></mrow></semantics></math></inline-formula>, and subthreshold swing of 85 mV/dec with significantly reduced gate leakage current (I<sub>G</sub>) of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>9.1</mn><mo> </mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>10</mn></mrow></msup></mrow></semantics></math></inline-formula> A/mm.https://www.mdpi.com/2073-4352/11/2/136AlGaN/AlN/GaNgallium oxideMOS-HEMTHfSiO<sub>X</sub>UV/O<sub>3</sub>passivation |
| spellingShingle | Soumen Mazumder Ssu-Hsien Li Zhan-Gao Wu Yeong-Her Wang Combined Implications of UV/O<sub>3</sub> Interface Modulation with HfSiO<sub>X</sub> Surface Passivation on AlGaN/AlN/GaN MOS-HEMT Crystals AlGaN/AlN/GaN gallium oxide MOS-HEMT HfSiO<sub>X</sub> UV/O<sub>3</sub> passivation |
| title | Combined Implications of UV/O<sub>3</sub> Interface Modulation with HfSiO<sub>X</sub> Surface Passivation on AlGaN/AlN/GaN MOS-HEMT |
| title_full | Combined Implications of UV/O<sub>3</sub> Interface Modulation with HfSiO<sub>X</sub> Surface Passivation on AlGaN/AlN/GaN MOS-HEMT |
| title_fullStr | Combined Implications of UV/O<sub>3</sub> Interface Modulation with HfSiO<sub>X</sub> Surface Passivation on AlGaN/AlN/GaN MOS-HEMT |
| title_full_unstemmed | Combined Implications of UV/O<sub>3</sub> Interface Modulation with HfSiO<sub>X</sub> Surface Passivation on AlGaN/AlN/GaN MOS-HEMT |
| title_short | Combined Implications of UV/O<sub>3</sub> Interface Modulation with HfSiO<sub>X</sub> Surface Passivation on AlGaN/AlN/GaN MOS-HEMT |
| title_sort | combined implications of uv o sub 3 sub interface modulation with hfsio sub x sub surface passivation on algan aln gan mos hemt |
| topic | AlGaN/AlN/GaN gallium oxide MOS-HEMT HfSiO<sub>X</sub> UV/O<sub>3</sub> passivation |
| url | https://www.mdpi.com/2073-4352/11/2/136 |
| work_keys_str_mv | AT soumenmazumder combinedimplicationsofuvosub3subinterfacemodulationwithhfsiosubxsubsurfacepassivationonalganalnganmoshemt AT ssuhsienli combinedimplicationsofuvosub3subinterfacemodulationwithhfsiosubxsubsurfacepassivationonalganalnganmoshemt AT zhangaowu combinedimplicationsofuvosub3subinterfacemodulationwithhfsiosubxsubsurfacepassivationonalganalnganmoshemt AT yeongherwang combinedimplicationsofuvosub3subinterfacemodulationwithhfsiosubxsubsurfacepassivationonalganalnganmoshemt |