摘要 |
A method of forming an array of electron field emitters at a face of a semiconductor layer is disclosed. The method includes the steps of: providing a semiconductor workpiece having a plurality of field emitter sites on a face thereof; for each site, forming a conductive column having a base coupled to the site and an upstanding end opposed to the base; for each conductive column, forming a metallic column on the upstanding end of the conductive column; depositing an electrically conductive polymer layer over the workpiece; etching the electrically conductive polymer layer to selectively expose the metallic columns; placing the workpiece in an electrolytic etchant solution capable of etching the metallic columns; applying an electric potential between the conductive polymer layer and an anode electrode in the etchant to etch the metallic columns into a respective plurality of sharp emitter tips; and removing the conductive polymer layer. Where the metallic column is tungsten, an aqueous solution of potassium hydroxide is disclosed as an etchant. Where the metallic column is a platinum-iridium alloy, an aqueous solution of calcium chloride and hydrochloric acid is disclosed as an etchant.
|