Deposition of ultrathin parylene C films in the range of 18Â nm to 142Â nm: Controlling the layer thickness and assessing the closeness of the deposited films

► We describe the deposition of ultrathin layers of parylene C (down to 18 nm). ► We describe a simple method to test the layers for closeness. ► Using this technique we show that parylene C layers thicker than 30 nm are closed.