Emission current measurements under simulated flat panel display conditions

Summary form only given. Flat panel displays represent a large market for field emission cathodes. Although many companies have made significant progress towards an emissive flat panel display, there still exist many questions on the performance, stability, and reliability of field emitters in the ambient composition and pressure found in a practical display. This study addresses these questions by testing silicon field emitter arrays in a variety of gases over a wide pressure range similar to that expected in commercial flat panel displays. Field emission depends strongly on the work function of the emitter surface. At any vacuum level, molecules will adsorb on the emitter surface and change the work function. The adsorbed molecule can be considered as a dipole aligned perpendicular to the emitter surface. When the negative charge is oriented away from the surface, the work function is increased in proportion to the number and dipole moment of the adsorbed molecules. The rate and ultimate steady-state change in the work function is roughly proportional to the pressure. The theory underlying these points will be presented and compared with experimental results.