Preparation Of PVDF Thin Film And Measurement Of Pyroelectric Unit Detector

Polyvinylidene fluoride(PVDF) polymer is an excellent pyroelectric material. PVDF film type pyroelectric detector with cost-effective and small size advatages, make it become a popular material for commercial and military preparation of pyroelectric detectors.This paperaims to research to terahertz pyroelectric unit devices based on the study of the PVDF film we prepared PVDF thin films by spin coating, Thinking for its small pyroelectric coefficient, the new doped Mg(NO3)2.6H2 O technology is applied for to improve the β-phase crystal in PVDF film, Which got high pyroelectric properties of PVDF film. The dielectric ferroelectric and pyroelectric properties of PVDF film and PVDF/Mg(NO3)2.6H2 O composite film are studies. and The unit device is prepared. We set up a test platform to test the performance of a unit device.Preparation of PVDF film and its dielectric, ferroelectric, pyroelectric properties is studied. The studies includes:(1)preparing PVDF thin films on Al and FTO subtrates, we discusses the effect of different solvents, different annealing situation, different test thermal on PVDF thin film and the dielectric, ferroelectric, and pyroelectric properties.(2) We test the hysteresis loops of PVDF film, the leakage current and the pyroelectric coefficient after testing the electric polarization.(3) In the experiment, the leakage current is 1.5×10-8A, Pr(remanent polarization) = 0.65μC/cm2, Ec(coercive field) = 39V/μm, the pyroelectric coefficient at 100V/μm polarization field strength is 8.7×10-10 C / Kcm2.PVDF film by solution method only contains a small amount of β crystal phase, with lower pyroelectric property. This paper presents a new technology of doped Mg(NO3)2.6H2 O to obtain high β phrasein PVDF/Mg(NO3)2.6H2 O composite film. and its surface morphology, infrared spectroscopy, dielectric leakage. Ferroelectric, pyroelectric properties were studied. Under 1KHzconditions, PVDF/Mg(NO3)2.6H2 O composite film relative dielectric constant is 10.8, dielectric loss is 0.05; leakage current is-1.28×10-10A; remanent polarization Pr=1.22μC/cm2; coercive field Ec = 50v/μm, pyroelectric coefficient p = 6.3×10-9C?cm-2?K-1, calculate the voltage response of merit 2.3×10-10 C?cm?J-1and probe excellent value of 4.3×10-9C?cm?J-1. In this study, PVDF/Mg(NO3)2.6H2 O composite films have excellent pyroelectric properties.The PVDF film terahertz pyroelectric unit detector is studied, the structure of the plane PVDF pyroelectric unit detector is prepared. The pyroelectric detector unit PVDF film and PVDF/Mg(NO3)2.6H2 O films were tested according to terahertz testing system by laboratory their own building.