Abstract: A method for forming a thin film electrode for an organic thin film transistor of the invention provides a multi-layer mask on a substrate with an electrode area opening in a top layer of the mask that is undercut by openings in other layers of the mask. A thin film of metal is deposited in the electrode area on the substrate. Removing the multi-layer mask leaves a well-formed thin film electrode with naturally tapered edges. A preferred embodiment of the invention is a method for forming a thin film electrode for an organic thin film transistor. The method includes depositing a first layer of photoresist on a substrate. The photoresist of the first layer has a first etching rate. A second layer of photoresist is deposited on the first layer of photoresist. The photoresist of the second layer has a second etching rate that is lower than the first etching rate. The first and second layer of photoresist are patterned by exposure.