Impact of in situ NH3 pre-treatment of LPCVD SiN passivation on GaN HEMT performance
Artikel i vetenskaplig tidskrift, 2022

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.





NH3 pretreatment


Chen Ding Yuan

Chalmers, Mikroteknologi och nanovetenskap, Mikrovågselektronik

Axel R. Persson

Linköpings universitet

Kai-Hsin Wen

Chalmers, Mikroteknologi och nanovetenskap, Mikrovågselektronik

Daniel Sommer

United Monolithic Semiconductors (UMS)

Jan Grunenputt

United Monolithic Semiconductors (UMS)

Herve Blanck

United Monolithic Semiconductors (UMS)

Mattias Thorsell

Chalmers, Mikroteknologi och nanovetenskap, Mikrovågselektronik

Olof Kordina


Vanya Darakchieva

Linköpings universitet

Lunds universitet

Per O. A. Persson

Linköpings universitet

Jr-Tai Chen


Niklas Rorsman

Chalmers, Mikroteknologi och nanovetenskap, Mikrovågselektronik

Semiconductor Science and Technology

0268-1242 (ISSN) 1361-6641 (eISSN)

Vol. 37 3 035011


Medicinsk apparatteknik


Den kondenserade materiens fysik



Mer information

Senast uppdaterat