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Microsyst Technol
DOI 10.1007/s00542-014-2215-7
REVIEW PAPER
Design principles and considerations for the ‘ideal’ silicon
piezoresistive pressure sensor: a focused review
S. Santosh Kumar · B. D. Pant
Received: 29 April 2014 / Accepted: 2 May 2014
© Springer-Verlag Berlin Heidelberg 2014
and future trends have also been discussed. This paper will
serve as a quick and comprehensive guide for pressure sen-
sor developers.
1 Introduction
The advancements in silicon substrate manufacturing
technology (Fisher et al. 2012) along with device process-
ing have contributed to a significant growth in the field
of microelectromechanical systems (MEMS). Microsen-
sors and microactuators fabricated using MEMS technol-
ogy convert one form of energy to other using different
transduction mechanisms (Judy 2001). Initially, MEMS
borrowed the processes from the integrated circuit (IC)
industry, but there has been a major evolution in processes
specifically used in MEMS, like surface micromachining
(Bustillo et al. 1998) and bulk micromachining (Kovacs
et al. 1998). Micromachined mechanical sensors like pres-
sure sensors, accelerometers, and gyroscopes have a wide
range of applications leading to highest amount of sales
volumes in the sensor arena (Yazdi et al. 1998). Pressure
sensors constitute a large share in the MEMS mechanical
sensor market. They were one of the first commercial-
ized MEMS-based sensors. A pressure sensor is generally
the first item in a chain of instruments that provide data
related to pressure of fluids (liquids and gases) for cor-
rect operation of systems and machines (Ripka and Tipek
2007). MEMS based pressure sensors help in replac-
ing the bulkier version of their traditional electrical and
mechanical counterparts. Traditional pressure sensors such
as manometers, bourdon tubes, diaphragms, and bellows
(Tandeske 1991) operate by converting the mechanical
motion caused by the pressure into the motion of a dial
which indicates the applied pressure. On the other hand, in
Abstract Over the past four decades, the field of silicon
piezoresistive pressure sensors has undergone a major revo-
lution in terms of design methodology and fabrication pro-
cesses. Cutting edge fabrication technologies have resulted
in improved precision in key factors like dimensions of dia-
phragm and placement of piezoresistors. Considering the
unique nature of each sensor and the trade-offs in design,
it is not feasible to follow a standard design approach.
Thus, it is useful to derive the specific design from a num-
ber of important factors to arrive at the ‘ideal’ design. In
this paper, we critically review and analyze the various
design considerations and principles for silicon piezore-
sistive pressure sensor. We also report the effect of these
considerations on the sensor output taking help of various
CAD tools. Keeping in view the accuracy of state-of-the-
art fabrication tools and the stringent demands of the pre-
sent day market, it has become important to include many
of these design aspects. Modelling using analytical expres-
sions for thin plates has also been looked into as it gives a
quick guideline and estimation of critical parameters before
detailed finite element method analysis. Wherever possi-
ble, fabrication imperfections and their effects have been
discussed. Dependency of piezoresistive coefficients on
temperature and doping concentration, the effect of clamp-
ing condition of diaphragms and fabrication using wet
bulk micromachining is also analyzed. Silicon-on-insula-
tor based sensors along with innovative design strategies,
S. S. Kumar (*) · B. D. Pant
CSIR-Central Electronics Engineering Research Institute
(CEERI), Pilani 333031, Rajasthan, India
e-mail: santoshkumar.ceeri@gmail.com
S. S. Kumar · B. D. Pant
Academy of Scientific and Innovative Research (AcSIR),
New Delhi, India