Title :
Piezoelectric and ferroelectric properties of aliphatic polyurea films synthesized by vapor deposition polymerization
Author :
Hattori, Takeshi ; Takahashi, Yoshikazu ; Iijima, Masayuki ; Fukada, Eiichi
Author_Institution :
Tsukuba Inst. for Super Mater., ULVAC Japan Ltd., Tsukuba, Japan
Abstract :
Thin films of aliphatic polyurea films were synthesized on the cooled substrates by vapor deposition polymerization. Poling dynamics of the films depended on the crystallinity. Polyurea-5 exhibited ferroelectric hysteresis. The maximum values of piezoelectric stress constant e31 and pyroelectric constant p3, obtained for polyurea-5 poled at Ep=250 MV/m, Tp=150°C and tp=10 min, were 15 μC/m2K and 10 mC/m2, respectively. Three relaxations were found similar to nylon in the temperature dependence of the elastic constant c1, the dielectric constant ε3 and the piezoelectric constant e31
Keywords :
dielectric hysteresis; ferroelectric thin films; piezoelectric thin films; polymer films; polymerisation; vapour deposited coatings; aliphatic polyurea film; cooled substrate; crystallinity; dielectric constant; elastic constant; ferroelectric hysteresis; ferroelectric properties; piezoelectric properties; piezoelectric stress constant; poling dynamics; polyurea-5; pyroelectric constant; relaxation; synthesis; temperature dependence; vapor deposition polymerization; Chemical vapor deposition; Crystallization; Ferroelectric films; Ferroelectric materials; Hysteresis; Piezoelectric films; Polymer films; Pyroelectricity; Sputtering; Stress;
Conference_Titel :
Electrets, 1996. (ISE 9), 9th International Symposium on
Conference_Location :
Shanghai
Print_ISBN :
0-7803-2695-4
DOI :
10.1109/ISE.1996.578213
