9209740 PANG Vacuum devices, although still in the development stage, have already show significantly promise in a number of applications. Besides being able to operated at very high frequency and immune to radiation, it has been recently demonstrated as a product for flat panel display in France. One of the major drawbacks for vacuum devices is related to the fabrication technology. A number of issues have yet to be resolved before the devices can achieve its full potential. The emitters properties including their electrical, thermal, mechanical stability are often not optimized. To improve the performance of these devices, alternative materials and new fabrication technology have to be developed. In this project, field emitter arrays for vacuum devices will be fabricated. Two new materials will be tested as emitters, including WSi2 and InP. For Wsi2 emitters, it will be formed by either sintering W deposited on Si emitters or by patterning WSi2 that is deposited directly on the substrate. High resolution patterning techniques including electron beam and masked ion beam lithography will be used to define emitters with submicrometer dimensions in resist. Wet chemical etching and dry etching techniques will be for generating vertical profiles for the emitters. The emitter tips will be sharpened by various dry etching conditions after the vertical emitters are formed, including faceting, undercutting, mask erosion, and dopant dependent dry etching. In order for the vacuum devices to be operational in air, a sealed triode structure will be fabricated using double angle evaporation. ***
