As far as I know, there is no such report. But for several nm thick PVDF, in other words, several monolayers, the LB technique is much more convenient I think. There are a lot of paper on that topic.

Thank you very much Le Zhang.

We prepared cop-PVDF films by thermal evaporations. One can find  in Russian Journal

-Yudin S., Draginda Yu., Palto S., Yablonskii S.,Vacuum evaporated films from cop-PVDF,  Kristallographiya 2012, N57 pp  471-481 (Rus). It is possible to find eng. version.

Do you have any link of the article Serguei? I could not find it from Google. It will be of great help if you can share the link. Thanks.

Impossible. the moment you heat PVDF for thermal evaporation, it should become carbon black.

Spin casting is the best way out to deposit a very thin film.

Make the PVDF film preferably in MIM confirguration, deposit this MIM structure on a stretchable elastic substrate, so that you can strain the PVDF layer, and then pole the film.  You are suggesting a very thin PVDF layer, therefore I would suggest it should be pin hole free film. If you are able to pole the film ( you may need very small voltages as you have a very thin film), you may then try to make some d31 measurements, and see if such thin films are become piezoelectric.

I must say you have your sight on a very interesting problem, small technical challenges on the way, but depend on spin casting to obtain a thin film.

K. Sreenivas

There are CVD techniques by KK Gleason et al that may be helpful, or a MAPLE deposition as shown by RD Priestley that could work.

Hi

I am also interested in similar challenge.However mine also includes PVDF coating in a porous anodic alumina material. Thickness of film from 2-20nm is the objective, however preference is on thickness of less than 5nm.I know of a publication where 15nm thick nanotubes of PVDF were formed using anodic alumina membranes as template.(Li et al, 2013 dx.doi.org/10.1021/cm3028466 | Chem. Mater., 25, 524−529)

I do not have a background in material sciences so would like ask for your opinions/suggestions on sort of processes/techniques that can be used to achieve same. Considering special features of anodic alumina membranes (i.e isoporous, straight pore channels and porosity of 40-50%), would it be possible to use CVD for internal coating as well.

Thanks.

Thanks for all your answers. We tried with the thermal evaporation of PVDF and the 20 nm films that we evaporated was around 2-3 nm rough. We prepared both as deposited and the films annealed for 2 hours at 135 degrees. Both kind of films showed close to 160 degree phase switching (not 180 deg. completely) and also domains could be written on them using contact AFM, However ferroelectric response was better from the annealed samples compared to the as-deposited ones. However, I believe that still there is plenty of room for improvement of ferroelectricity by optimizing the growth condition.

I deposited PVDF, PClTFE etc films by thermal evaporation in vacuum since 1987.

The PVDF film can be deposited using special precautions to avoid polymer microdrops.

But: such very thin film contains macrochains aggregates and their boundaries; I am not sure, that such thin film can be made without pinholes. There are methods to supress crystallisation and make film amorphous and smooth, but the structure will not be equal to bulk PVDF one and properties as well.

Space–charge-limited conduction in vacuum-deposited PVDF films

Authors

S. P. Bodhane,

V. S. Shirodkar

First published: 24 August 1999Full publication history

DOI: 10.1002/(SICI)1097-4628(19991107)74:63.0.CO;2-KView/save citation

Cited by: 5 articlesRefresh citation countCiting literature

Thanks a lot for your answer Konstantin. Do you have any publications on this work? Would be of great help.

No.  The some data just in my Ph.D. paper in Russian.

We have synthesized PVDF thin films applying the spin coating. The thickness is in the order of 10 to 150 nm. I have annealed in vacuum. We got good surface morphology. We can also see spherulites. Use polarized light microscopy and AFM for better results.