Low cost spinner developed for deposition of thin films used in OLED devices

Abstract

This work aims the development of a compact spinner to be used inside the glove-box chamber to deposition of polymeric thin films used in the build of OLED devices. Initially, ten fans extracted of microcomputers were tested with commercial multi-voltage power supply. Four fans were selected based on the standard deviation of speed. A variable power supply was also built in order to get a more detailed response in terms of electrical current and speed in function of applied voltage. The fan that showed less variation of speed with applied voltage was selected for deposition tests using polymeric photoresist solution on the ITO (indium tin oxide) coated glass. This polymer was deposited by spin-coating at different speeds: 1000, 2000, 3000 and 4000 rpm and dried for the thicknesses measurement revealing good uniformity. Finally, three OLED devices were assembled with 2000 and 3000 rpm and the layers were dried under the same conditions. In the structure of the devices were used the materials deposited layer-by-layer:glass/ITO/PEDOT:PSS/ Polyfluorene (PFpf)/Al. The OLED devices revealed blue light electroluminescence. The I-V curves showed better performance for OLED devices mounted at 2000 rpm with higher current density and similar appearance to the diode curve.