SBIR-STTR Award

This phase I SBIR proposal addresses development of low voltage (< 10 V), high current (~ 10 µA/tip) nanoscale Si field emission deveices capable of operating at atmospheric pressure. Earlier work has demonstrated the feasibility of low-voltage operation in air, however, either the currents were too low (~ 10 nA/tip), or separation between cathode and anode was > few µms. We propose application of nanofabrication methods to form closely spaced arrays of Si field emitters (tips and wedges). Using reactive ion etching, wet-chemical etching, and hermal oxidation, the tip radius is reduced to ~ few nms and cathode-anode separation to ~ 50-250 nm range. Since, the mean free path of electrons in air is ~ 250 nm, this separation coupled with emitter radius will allow low-voltage operation in air at high current. Vertical and lateral field emission devices are proposed. Wherass vertical devices use conventional nanofabrication methodology, the lateral device configuration incorporates an innovative configuration comprising of vertically stacked independently controlled emitters to significantly enhance current per unit area. Finally, these structures can serve as templates for cold cathode emitters by suitable deposition of metal and removal of Si.

Benefits:
Vacuum microelectronics, Rad-hard microelectronics, nanolithography, displays, AFMs

Keywords:
Silicon nanofabrication, Field emission devices, plasma displays

This phase II SBIR proposal is aimed at development of low-power field emission display devices. Flat panel display market is one of the fastest growing technology sectors. Despite its fundamental strengths, the role of field emission (FE) technology in the market place is marginal at best. This is in part due to the inability to operate efficiently at low power. Low-power operation requires a highly efficient cold cathode and phosphor films capable of producing suitable fluorescence at low electron energies. We address efficient cathode formation though geometric field enhancement using our nanoscale patterning expertise. The low-power phosphor films will be addressed through partnership with the display research group at the University of Texas at El Paso. Finally, we propose a novel multilayer emitter concept aimed at lateral field emission displays. The technology developed will also find military and air force applications through low-power, low-weight, temperature-insensitive, and rad-hard device characteristics.

Benefits:
Field emission displays, Nanoscale electronics, molecular electronics

Keywords:
Si, W, and MO field emission tips,Nanoscale patterning, phosphor filma for low power displays