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. The design of the sensitive element with the integration of thin piezoelectric PZT films and 
metal film strain gages
Another variant of the sensor element is a cross-shaped beam located along the perimeter of the 
support ring, on which a bridge circuit of metal-film strain gages and piezoelectric capacitive 
structures based on PTZ is formed (fig.2 ).
 
Figure 2
. Sensitive element with the integration of thin piezoelectric PZT films and metal film 
strain gages. 

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SPbOPEN 2019
Journal of Physics: Conference Series
1410 (2019) 012230
IOP Publishing
doi:10.1088/1742-6596/1410/1/012230
4
The beam is made of an elastic alloy with a high elasticity modulus 36NiCrTiAl. In this structure, the 
strain gages are formed by the technology of thermal vacuum evaporation of the alloy H
20
N
75
YU.
PTZ thin films are formed by HF-sputtering from a PTZ ceramic target at a power of 300 W, in an
Ar - O
2
stream (1: 1).
The composition corresponds to a rhombohedral solid solution adjacent to the morphotropic phase 
boundary. Lead losses were compensated by adding 10 mol % PbO. The deposition temperature was 
400 °C, the film thickness corresponded to the range from 0.5 to 0.8 μm, the annealing temperature 
was 570 °C. The strain gages before the PZT film deposition were passivated with the Si
3
N
4
film 
obtained by the method of low-temperature plasma chemical deposition, in order to prevent the 
introduction of contaminants of the PZT target sputtering process, resulting the strain gages 
degradation. Further, the upper plates of the ’’titanium-gold’’ structure were formed by the method of 
resistive evaporation, similarly to the lower plates. 
Further assembly of the sensing element is carried out mechanically without high heat, which can 
affect the polarized state of the PZT film. The use of polar dielectrics in this structure is not justified 
due to the low films piezomodule, which, in combination with a small beam of an elastic alloy, will 
not cause a proper output signal. 
5. Conclusion 
These structures allow to register a wide range of both statistical and dynamically changing pressure 
values with small deviations from the actual values. At the same time, the possibility of sensitive 
systems prototypes manufacturing is confirmed by the modeling results.