Paper • open access

 
1. Introduction 
The requirements increase for technical systems determine the growth of measurement volumes and 
the number of investigated parameters [1]. At the same time, sensor devices must have not only 
advanced functionalities, but also the smallest designs. In such conditions, multifunctional sensitive 
elements with integrated thin strain-resistive and piezoelectric films are able to perform the tasks 
associated with the registration of the maximum range of determined pressures. Such assemblies have 
a small geometric structure, which the theoretical model can be manufactured industrially.
The creation of such structures became possible due to the technological breakthrough in the field of 
the synthesis of thin ferroelectric PZT films, as well as polar dielectrics ZnO and AlN [2-8]. 
2. Applicable materials 
The cultivation of highly textured piezoelectric thin films ZnO and AlN with clearly defined 
thicknesses across the entire substrate is currently being implemented at an industrial level [9]. 
To determine the dynamic pressure, films based on polar dielectrics AlN and ZnO are used, which 
under normal conditions crystallize into a hexagonal lattice of the wurtzit type (W4) or lead titanate 
zirconate (PTZ) with piezoelectric properties, having a perovskite structure. Table 1 presents the 
effective parameters of thin piezoelectric films. 
Table 1.
Parameters of piezoelectric films. 
Parameter 
Aluminum nitride AlN
 
Zinc oxide ZnO
 
Lead titanate zirconate PTZ 
ε
33,f 
8 – 12 
10,4 
900 – 1300 
d
33,f 
, (pKl/H) 
10 –12 
3,4 – 3,9 
90 – 110 
k 
2
p,f
0,06 – 0,085 
0,065 – 0,11 
0,1 – 0,20 
density, (g/cm
3
) 
5,68 
3,26 
7,5 – 7,6 
moduleYoung, (GPA) 
110 – 150 
260 –380 
60 – 80 

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SPbOPEN 2019
Journal of Physics: Conference Series
1410 (2019) 012230
IOP Publishing
doi:10.1088/1742-6596/1410/1/012230
2
PZT thin films with piezoelectric properties have a perovskite-type structure. The spontaneous electric 
dipole moment of PZT films can be reoriented between certain crystallographically stable states using 
appropriate levels of the electric field that do not lead to dielectric breakdown. In the perovskite 
structure of ABO3, where A is a bivalent ion, B is a tetravalent ion, the cubic lattice may be distorted 
at temperatures below the Curie temperature. These distortions shift the octahedrally oriented cations 
from the center of the structure. Accordingly, a dipole moment is created between the center of the 
negative charge created by the oxygen octahedron and the center of the positive charge created by the 
cation sublattice. The shifts in the position of the A-ions of Pb
+2
, like the B-ions of Zr
+4
and Ti
+4
, 
determine the properties of the PZT (ZrxTi1 - x) O
3
dipoles [10]. 
The values of the piezoelectric parameters of thin perovskite PZT films exceed the similar parameters 
of AlN and ZnO. However, the stability of the characteristics of the piezoelectric parameters of polar 
dielectrics is much higher and their production has been mastered much more widely, which in turn 
imposes restrictions on the use of PZT films. For industrial production of thin piezoelectric PZT films, 
a number of fundamental tasks are required to be solved: the development of the physical 
fundamentals of the technology for manufacturing low-dimensional piezoelectric films; the study of 
the features of the piezoelectric state and the switching mechanisms of spontaneous polarization; the 
creation of conditions of the polarized state stable in time [5, 6, 11]. Moreover, the further integration 
of piezoelectric perovskite films with used deposition modes with strain-resistant semiconductor 
pressure sensors is limited by the high temperatures of sensitive elements production.