Low Gate Lag Normally-Off p-GaN/AlGaN/GaN High Electron Mobility Transistor with Zirconium Gate Metal

Abstract

The impact of gate metal on the leakage current and breakdown voltage of normally-off p-GaN gate high-electron-mobility-transistor (HEMT) with nickel (Ni) and zirconium (Zr) metals were studied and investigated. In this study, a Zr metal as a gate contact to p-GaN/AlGaN/GaN high mobility transistor (HEMT) was first applied to improve the hole accumulation at the high gate voltage region. In addition, the ZrN interface is also beneficial for improving the Schottky barrier with low nitrogen vacancy induced traps. The features of Zr are low work function (4.05 eV) and high melting point, which are two key parameters with p-GaN Schottky contact at reversed voltage. Therefore, Zr/p-GaN interface exhibits highly potential for GaN-based switching power device applications.

Hole Injection Effect and Dynamic Characteristic Analysis of Normally Off p-GaN HEMT with AlGaN Cap Layer on Low-Resistivity SiC Substrate

“…As revealed by Figure 3 b, the device exhibited a high off-state breakdown voltage of 763 V. We used pulse measurement to analyze the hole injection effect and dynamic characteristics of the device under various stress voltages V GSQ and durations. To evaluate the gate lag behavior we employed the AM-241 pulse measurement system [ 16 , 17 ]. The operation condition and gate lag measurement are illustrated in Figure 4 a,b, respectively.…”

Improved Ion/Ioff Current Ratio and Dynamic Resistance of a p-GaN High-Electron-Mobility Transistor Using an Al0.5GaN Etch-Stop Layer

“…The Maury AMCAD pulse IV system was used to further investigate trapping/detrapping phenomena and the dynamic behavior of the devices [ 18 , 19 ]. Furthermore, the I DS – V DS characteristics were also measured from different quiescent bias points at V GS = 4 V to investigate the influence of off-state gate bias stress on dynamic R ON and I DS , as illustrated in Figure 5 .…”

Study of MoN gate impact on GaN high electron mobility transistor

“…To improve the long-term system performance, reliability investigations of GaN-based MMICs have been widely reported for millimetre-wave applications in the past few years [5][6][7]. Various kinds of processing technologies have been reported for reliability improvement of GaN HEMTs [8,9], especially, gate engineering by adopting refractory gate metals such as Zr/Au gates [10], TiN/Cu gates [11] or W/Au gates [12], which are reported to be essential for improving long-term gate stability. Because of its thermal stability, molybdenum nitride (MoN) has attracted increasing attention [13,14].…”