Suppression of Dispersive Effects in AlGaN/GaN High-Electron-Mobility Transistors Using Bilayer SiN _x Grown by Low Pressure Chemical Vapor Deposition

Impact of Silicon Nitride Stoichiometry on the Effectiveness of AlGaN/GaN HEMT Field Plates

“…Some of these problems can be reduced by building devices with well optimized field plates (FPs) [5,6], together with a SiNx passivation/encapsulation deposition process. Previous work on the silicon nitride deposition process has measured DC characteristics and current collapse [7][8][9][10][11][12]. Here, in addition to this we demonstrate the impact of SiNx changes to the channel electric field profile which is critical to device reliability.…”

Low-Pressure-Chemical-Vapor-Deposition SiNx passivated AlGaN/GaN HEMTs for power amplifier application

“…Those results confirm that the deep-level traps are dramatically compensated in Bilayer-Chip. On the other hand, regarding the amount of gate leakage (Ig) current among the three chips, the PECVD-Chip displayed the largest one around 10 -3 A/mm, which is supposed to be caused by shallow traps [8]. Ig in Bilayer-Chip locates between 10 -5 and 10 -4 A/mm, which is believed can be further reduced by optimizing the first layer's thickness and chemical stoichiometry.…”

“…MMIC foundries are also making great efforts in improving passivation schemes to enhance the power density and operation reliability. On the other hand, there are few publications about low-pressure-chemical-vapor-deposition (LPCVD) SiNx passivation, which is grown at high temperature can offer a thermal-stable and compact dielectric layer [8]. In this work, LPCVD bilayer SiNx was presented to effectively suppress the magnitude of current collapse, by comparing its the pulse IV and load-pull performance with both in-situ and ex-situ SiNx.…”

On the different origins of electrical parameter degradation in reverse‐bias stressed AlGaN/GaN HEMTs

“…Ironically, the passivation layers that are used to minimize the current collapse can lead to a false correlation between bias‐stress‐induced physical degradation and deteriorated electrical parameters. Firstly, opaque passivation layers do not allow precise probing of extremely localized defects underneath (and the resulting lattice distortion, if any) .…”