Application of ion beam etching technique to the direct fabrication of silicon microtip arrays

A relatively simple and effective method to directly fabricate large-area field emission microtip arrays on n-type silicon wafers is proposed. The presented fabrication approach of silicon microtip devices mainly involves photolithography, thermal shaping and consolidation, argon ion beam etching and sputtering deposition. The measurements show that the silicon field emission microtip devices fabricated have good structural uniformity and electrical characteristics. The center-to-center spacing of microtips fabricated is 50 μm and the typical microtip height about 11 μm. The scanning electron microscope analysis and the surface style measurements are carried out for the surface morphologies of silicon microtips, such as square-bottom pyramid-shaped microtips, cone-shaped microtips, square-bottom circle-microtips, and circle-bottom circle-microtips. Electrical measurements are performed to obtain the typical field emission properties of the devices. The experiment results show that the method utilized can be applied to fabricate silicon field emission microtip arrays and circle-microtip arrays of larger area.