Vol.:(0123456789) 1 3
Applied Physics A (2020) 126:487
https://doi.org/10.1007/s00339-020-03616-0
Implementation of digital‑to‑analog converter through CP‑based
GaAs/GaSb nanowire GAA‑TFET
Anil Lodhi
1
· Chithraja Rajan
1
· Dheeraj Sharma
1
· Amit Kumar Behera
1
· Dip Prakash Samajdar
1
· Atul Kumar
1
Received: 23 November 2019 / Accepted: 8 May 2020
© Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract
Digital-to-analog converter (DAC) is the most critical circuit of any chip which limits system performance and consume
much power. Therefore, the focus of this work is the DAC implementation using GaAs/GaSb-based charge plasma nanow-
ire GAA-TFET which provide better ON current at reduced ambipolarity and hence, reduce power consumption. Also, the
linearity of the proposed device is much better than Si TFET due to the absence of random dopant fuctuation and hence,
improves DAC accuracy. The DAC implemented here is the R–2R and current steering architecture which is the frst ever
known work of a charge plasma-based hetero-material nanowire TFET. For the DAC implementation, Verilog A lookup
table is created from the simulated results of this device from TCAD Silvaco and rest of the circuit simulation is carried out
in Cadence. Finally, DAC performance metrics have been analyzed and found that efciency of current steering has been
drastically improved compared to R–2R architecture.
Keywords Nanowire · GAA · TFET · Charge plasma · Hetero-material · High K dielectric · DAC
1 Introduction
CMOS has reached to the extend where short channel
efects (SCE’s) [1] has become bottleneck for the developing
resource constraint electronic industry. Limited subthreshold
swing (SS) and OFF-state leakage current suppress CMOS
scaling beyond 40 nm. These limitations motivated arise
of novel semiconductor devices for low power applications.
One such boom is tunnel FET (TFET) [2]. TFET stood its
separate place in low power devices as such its SS is not
limited to 60 mV/dec and very low of current [3]. However,
the lack of sufcient on current and high ambipolarity in Si
TFET restricted its exposure in circuit applications. Nev-
ertheless, many researchers had focused to improve TFET
characteristics, but their utilization in circuits is ceased
because of the absence of novel device model fles. There-
fore, in this paper, we are introducing a high performing
low power charge plasma (CP)-based GaAs/GaSb nanowire
gate all around tunnel FET (GaAs/GaSb-NW-GAA-TFET)
for digital-to-analog Converter (DAC) for the frst time. CP
creates pseudo source and drain regions through metal work
function engineering which avoid any specifc regional dop-
ing. Therefore, CP devices are immune to random process
variations and produce accurate results, which provide bet-
ter ON current at reduced ambipolarity and hence, reduce
power consumption. Indeed, highly linear device are the
uttermost importance for converters. Therefore, the proposed
CP-based device, which avoid sharp doping boundaries and
junctions, shows considerable improvement in linearity as
compared to Si TFET is proved to be a good choice for fault-
free DAC architecture.
The DAC [4] is a system that reconstructs an analog
waveform according to a digital word input. The informa-
tion transmitted through wireless is digital, but the signals
* Anil Lodhi
lodhianil011@gmail.com
Chithraja Rajan
rajan.chithraja@gmail.com
Dheeraj Sharma
dheeraj24482@gmail.com
Amit Kumar Behera
amitiiit12@gmail.com
Dip Prakash Samajdar
dipprakash010@gmail.com
Atul Kumar
atul.kumar@iiitdmj.ac.in
1
PDPM Indian Institute of Information Technology,
Design and Manufacturing, Jabalpur, Jabalpur 482005,
Madhya Pradesh, India