Fast Speed LIGBT with N-region Controlled
Segmented Anode
Wensuo Chen
1,2
Ruijin Liao
2
Yi Zhong
1
Peijian Zhang
1
Rongkan Liu
1
Yukui
Liu
1
Tian Xiao
1
Yong Liu
1
1. Chongqing Semi-chip Electronics Co., Ltd, Chongqing 401332, China
2. State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing
University, Chongqing 400044, China
Abstract—A novel n-region controlled segmented anode LIGBT on SOI substrate is proposed and
discussed. The n-region controlled segmented anode concept makes this new structure have lower on-state
voltage drop during conducting state and have two effective paths for electrons extracting during turn-off-state.
As simulation results shown, the turn-off time is 94.8% shorter than that of conventional one and 47.8%
shorter than that of state-of-the-art NCA-LIGBT which we have presented earlier. For drive application, the
proposed LIGBT has much lower total power loss than that of conventional and NCA-LIGBT. The proposed
device can be fabricated by the conventional SOI high voltage IC process, has a large scope of fabrication
parameter difference and it is a promising device used in low/middle voltage power ICs.
Key words: Turn-off time; On-state voltage drop; NDR; Power loss; Power ICs
1 Introduction
Lateral Insulated-Gate Bipolar Transistor (LIGBT)
is a promising power device for power ICs.
Conductivity modulation permits LIGBT to have low
on-state voltage drop, but it also cause the slow turn
off due to the removal of stored electron-hole plasma
in the drift region, which is strongly dependent on the
recombination process of the electron-hole pairs during
turn-off period. Shorted anode structures [1-2] have
fast switching characteristics, but the forward voltage
drop is larger than that of a typical LIGBT because of
its lower current gain. Furthermore, to prevent the
punch-through breakdown, a highly conductive
n-buffer region should be employed in anode region.
Therefore, in order to suppress Negative Differential
Resistance (NDR) regime in the forward
current–voltage (I-V) characteristics which can lead to
system instability [3], the p+ anode (as holes injector)
is usually designed to have long geometry. This makes
it less efficient silicon area using, especially for the
low/middle voltage power device (about 200V)
because of its small n-drift length. Consequently,
significant effort has been put into the optimization of
the LIGBT structure, such as passive PMOS driving
LIGBT [4-6], segmented anode LIGBT (SA-LIGBT)
[7], gradual hole injection dual gate LIGBT
(GHI-LIGBT) [8], NPN controlled LIGBT [9], and
dual gate inversion layer emitter transistor (DGILET)
[10]. Though these devices indicate the remarkable
This work is supported by the National Natural Science
Foundation of China (Grant No.
61404013), the
Chongqing
fundamental and frontier research project, China (Grant No.
cstc2013jcyjA40060
), and the Chongqing
Postdoctoral Science
Foundation funded project
, China (Grant No. xm2014085).