Conductor, resistor, and dielectric patterns of microelectronic device are usually defined by exposure of a photosensitive material through a mask onto the device with subsequent development of the photoresist and chemical removal of the undesired materials. Standard optical techniques are limited and electron lithography provides several important advantages, including the ability to expose features as small as 1,000 Å, and direct exposure on the wafer with no intermediate mask. This presentation is intended to report how electron lithography was used to define the permalloy patterns which are used to manipulate domains in magnetic bubble memory devices.The electron optical system used in our experiment as shown in Fig. 1 consisted of a high resolution scanning electron microscope, a computer, and a high precision motorized specimen stage. The computer is appropriately interfaced to address the electron beam, control beam exposure, and move the specimen stage.
Effects of Vector Maturation Time on the Dynamics of Cassava Mosaic Disease
