成果介绍
Abstract—In this work, we present the substrate bias
enhanced trap effects on time-dependent dielectric breakdown (TDDB) in GaN metal–insulator–semiconductor high
electron mobility transistors (MIS-HEMTs) by experiment.
Under different substrate biases, the shape parameter β
and scale factor η of the Weibull distribution are extracted
from the experimental data. A monotonical decrease in β
from intrinsic breakdown to extrinsic breakdown relating to
the hole-emission from the acceptor-like buffer traps with
increased negative substrate biases has been observed,
while η is increased at large positive substrate biases. This
unexpected increase in η suggests that the donor-like buffer
traps play an important role with a longer lifetime. The trap
mechanisms, relating to percolation path establishment,
are analyzed based on progressive breakdown (PBD). The
capacitance–voltage characteristics are measured during
each stress cycle confirming the hole fluence and electron
injection in the gate-stack layer with different trap distributions under various substrate biases. Finally, 2-D device
simulations are carried out to probe for physical insight into
the traps on TDDB failure mechanisms.
Index Terms—C–V measurement, device simulation,
GaN metal–insulator–semiconductor high electron mobility transistor (MIS-HEMT), substrate bias, time-dependent
dielectric breakdown (TDDB), trap mechanism.
团队介绍
Wen Yang , Graduate Student Member, IEEE, and Jiann-Shiun Yuan , Senior Member, IEEE