Improvement of the performance of a field-emission device with a metal mask

In a field-emission device, the background noise of the anode current is a little large due to the high anode voltage. Apart from this, the electron beam spreads because of the large gap between the cathode and the anode. To improve the performance of a field-emission device, a metal mask is introduced between the gate and the anode. Because the metal mask shields the electric field caused by the anode, the background noise of the anode current has been decreased about 90%. With a proper voltage applied on the metal mask, a convergence electric field is generated around the holes of the metal mask, so the focus performance of the electron beam is also improved. The width of the scanning line decreases from 3.1 mm to 0.9 mm after the metal mask is mounted. Because the metal mask can be fabricated in a large volume with low cost, the structure proposed in this paper has a promising application in the field-emission display devices. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim