Applications

1.1 Piezoelectric semiconductors and ceramics

Among semiconductor crystals, a family of wurtzite – type belongs to the 6mm class, which is piezoelectric active. The material properties (Tsai, 1992) and the norm calculations are in Table 1. From the table, the most piezoelectric effective among the five materials is CdS which has a very important feature in the thin films of semiconductors. For piezoelectric ceramics, the most potential piezoelectric material because of its higher strength, high rigidity and more importantly the better piezoelectricity, Table 2 includes the piezoelectric coefficients (Temple, 1960) and calculated norms. From the table, the most effective piezoelectric among the seven ceramics is PZT-5H.

Material

d11

d33

d15

N

BeO

-0.12

0.24

0.29

ZnO

-5.0

12.4

-8.3

18.48

CdS

-5.2

10.3

-14.0

23.50

CdSe

-3.9

7.8

-10.0

17.07

Table 1. The Constants and Norms of Piezoelectric Semiconductors[10-12 C N-1]

Material

d11

d33

d15

N

PZT-4

-5.2

15.1

12.7

24.59

PZT-5

-5.4

15.8

12.3

24.71

BaTi O3

-4.35

17.5

11.4

18.82

PZT-5H

-6.5

23.3

17

34.72

PZT-6B

-0.9

7.1

4.6

9.71

PZT-8

-4.0

23.3

10.4

28.13

C-24

1.51

8.53

3.89

10.37

Table 2. The Constants and Norms of Piezoelectric Ceramics [10-12 C N-1]