Engineered sculptured nematic thin films

By controlling the angular relation of the substrate surface with respect to the incoming vapor direction in an evaporation deposition system, it is possible to engineer the morphology of thin films. Sculptured nematic thin films result under low adatom mobility conditions when the substrates are rotated about an axis perpendicular to the vapor direction. Thin films of MgF2 were deposited onto room temperature substrates to produce columnar morphologies ranging from chevron structures to continuously varied structures resembling S shapes and C shapes. The specific morphologies are virtually unlimited within the restriction that the minimum angle χM of the local columnar direction with respect to the substrate plane is about 30°.