Impact of in situ NH3 pre-treatment of LPCVD SiN passivation on GaN HEMT performance
- 25 January 2022
- journal article
- research article
- Published by IOP Publishing in Semiconductor Science and Technology
- Vol. 37 (3) , 035011
Abstract
The impact on the performance of GaN high electron mobility transistors (HEMTs) of in situ ammonia (NH3) pre-treatment prior to the deposition of silicon nitride (SiN) passivation with low-pressure chemical vapor deposition (LPCVD ) is investigated. Three different NH3 pre-treatment durations (0, 3, and 10 min) were compared in terms of interface properties and device performance. A reduction of oxygen (O) at the interface between SiN and epi-structure is detected by scanning transmission electron microscopy (STEM )-electron energy loss spectroscopy (EELS) measurements in the sample subjected to 10 min of pre-treatment. The samples subjected to NH3 pre-treatment show a reduced surface-related current dispersion of 9% (compared to 16% for the untreated sample), which is attributed to the reduction of O at the SiN/epi interface. Furthermore, NH3 pre-treatment for 10 min significantly improves the current dispersion uniformity from 14.5% to 1.9%. The reduced trapping effects result in a high output power of 3.4 W mm−1 at 3 GHz (compared to 2.6 W mm−1 for the untreated sample). These results demonstrate that the in situ NH3 pre-treatment before LPCVD of SiN passivation is critical and can effectively improves the large-signal microwave performance of GaN HEMTs.Keywords
Funding Information
- European Union’s Horizon 2020 (823260)
- Swedish Foundation for Strategic Research (EM16-0024)
- Swedish Research Council VR (2016-00889)
- VINNOVA (2016-05190)
This publication has 27 references indexed in Scilit:
- Enhanced Breakdown Voltage With High Johnson's Figure-of-Merit in 0.3-$\mu{\rm m}$ T-gate AlGaN/GaN HEMTs on Silicon by $({\rm NH}_{4})_{2}{\rm S}_{x}$ TreatmentIEEE Electron Device Letters, 2013
- Impact of $\hbox{N}_{2}$ Plasma Power Discharge on AlGaN/GaN HEMT PerformanceIEEE Transactions on Electron Devices, 2011
- Dehydrogenation of defects and hot-electron degradation in GaN high-electron-mobility transistorsJournal of Applied Physics, 2011
- Impact of SF6 plasma treatment on performance of AlGaN/GaN HEMTVacuum, 2009
- A comparative study of surface passivation on AlGaN/GaN HEMTsSolid-State Electronics, 2002
- Discrete surface state related to nitrogen-vacancy defect on plasma-treated GaN surfacesApplied Physics Letters, 2002
- Trapping effects and microwave power performance in AlGaN/GaN HEMTsIEEE Transactions on Electron Devices, 2001
- Surface Chemical Treatment for the Cleaning of AlN and GaN SurfacesJournal of the Electrochemical Society, 2000
- Cleaning of AlN and GaN surfacesJournal of Applied Physics, 1998
- LPCVD against PECVD for micromechanical applicationsJournal of Micromechanics and Microengineering, 1996