Charge storage in Teflon AF films

The behavior of charge storage in corona charged and electron-beam irradiated Teflon AF films is investigated. Teflon AF film of 2 to 4 /spl mu/m thickness were prepared on glass substrates with Al and graphite electrodes by spin coating. Details of the experimental results are reported and discussed. For example, the measuring result of the laser-induced pressure pulse method shows that the velocity of the pressure pulse is 1.4 km/s. The maximum surface density depends mostly on the dielectric strength of the film, and the maximum potential of the free surface on the sample is directly proportional to the film thickness. The application of heat before, during or after charging can effectively improve the charge stability.