Ultrathin organic films can be used in electronics for several applications. There are a few ways of preparation of such films and one is plasma polymerization. Traditionally, comparatively thick films, 100–1000 nm, are deposited by this method and studied. But, for electronic devices, 10 nm or thinner films are of great importance to any wet technique considered to be unsuitable for perfect layer formation. In this work we have deposited 2–10 nm scale ultrathin hydrocarbon films on silicon wafers. A capacitively coupled rf discharge was initiated in a short residence time box-type reactor in a uniform flow of an acetylene/argon mixture. The gas kinetic residence time in the plasma zone was limited to 5–70 ms to decrease synthesis of heavy gas phase products and to suppress particulate formation. Distribution of film thickness after the deposition was measured by an ellipsometer. The film surface topography was studied by an atomic force microscope that shows the films are smooth and pinhole free. Thus our preliminary results suggest that ultrathin uniform smooth organic films suitable for electronic applications can be deposited in a reproducible manner.

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Ultrathin films of 2–10 nm thickness were deposited by pulsed discharge plasma polymerization. The film surface topography was studied by an atomic force microscope (AFM), which showed that the films are smooth and pinhole-free. The AFM was used to produce nanometer-scale indentations/holes in these deposited ultrathin organic films. The patterning process is governed by several factors: mechanical and Coulomb forces, heat effects, material transfer, and electric charge deposition depending on the conditions. The patterning results indicate the AFM can be used for the formation of nanometer-scale structures.

Nanometer-thick hydrocarbon films were plasma polymerized in a rf pulse discharge in an acetylene/argon mixture and were mechanically patterned by the AFM (atomic force microscope). In addition a dc bias voltage was applied to the gold coated Si3N4 AFM tip. Depending on the experimental conditions, different patterns have been observed: mechanical indentation, electric charge, and material deposition. The viscous properties of the plasma deposited film affects the movement of the AFM tip while it is scanning the surface in a contact mode, and also affects the size and shape of the patterned area. Spikes of about 25–72 nm height and 60–200 nm width were formed from gold transferred from the newly mounted gold coated tips. The mechanism of gold deposition could be assigned to the Joule heating of the tip, resulting from the electric breakdown of underlying dielectric layers.

Plasma polymerization by using a pulsed rf discharge was performed for preparation of ultra thin organic film. The discharge capacitively coupled was initiated in a box-type reactor at an uniform flow of an acetylene/argon mixture gas. 2-10 nm scale ultra thin hydrocarbon film was deposited on a silicon wafer. The surface topography of the film examined by AFM appears to be pinhole free. The distribution of thickness measured by an elipsometer suggested the reaction in gas phase is significant. Therefore, the theoretical calculation was performed by using a model of radical reaction in the gas phase, and the obtained equations were fitted well to the results of experiments.