INTERFEROMETRIC LITHOGRAPHY OF SUBMICROMETER SPARSE HOLE ARRAYS FOR FIELD-EMISSION DISPLAY APPLICATIONS

Interferometric lithography, the use of interactions between coherent laser beams to define subwavelength patterns, is well adapted to the p eriodic nature of field-emitter structures. Techniques to fabricate sp arse (hole diameter to pitch ratio of 1:3 or larger) emitter arrays to improve reliability and Lifetime are presented. These include: multip le exposures at two different pitches; integration of interferometric and optical imaging lithography; and various multiple beam techniques that both provide a sparse array and result in a two dimensional patte rn in a single exposure. Moire alignment techniques are demonstrated t o provide a simple process for aligning multiple levels. Manufacturing related issues such as process latitude and photoresist profiles and their suitability for subsequent processing are also discussed. Exposu re-dose process control using latent image monitoring is demonstrated. (C) 1996 American Vacuum Society.