The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself however may be best understood by reference to the following detailed description of the invention, which describes certain exemplary embodiments of the invention, taken in conjunction with the accompanying drawings in which:
A plurality of through holes 215 are defined on the first insulating layer 211, the gate conductive layer 212, the second insulating layer 213 and the confine layer 214. The through holes 215 are arranged in array such that the cathode plate 2 is exposed through a concave region 216 inside the through holes 215. A cathode unit 217 is arranged in the concave region 216 and corresponding vertically to the gate conductive layer 212. The cathode unit 217 further comprises a cathode electrode 217a and a cathode electron emitter 217b, where the cathode electrode 217a is arranged on the cathode plate 2 and the cathode electron emitter 217b is connected to the cathode electrode 217a. The cathode electron emitter 217b is composed of carbon nanotube to form the cathode electron emitting unit 21.
In the shown preferred embodiment, the anode plate 3 comprises an anode substrate 31 to be etched. The anode substrate 31 is a conductor and parallel to the cathode plate 2. The anode substrate 31 is fixed by an insulating support 5 on both sides thereof. An etch target 32 is placed at surface of the anode substrate 31 to defined an etching pattern. An anode mesh 6 is placed in front of the etch target 32 and is supported by the insulating support 5 on both sides thereof. The anode mesh 6 provides a high voltage to accelerate the electron beams.
With reference to
The electron beam 30 is confined by the confinement layer 214 and is accelerated by the anode mesh 6 in front of the substrate 31 to etch the target 32. The driver unit 4 controls the electron beam emitted from the cathode electron emitter 217b to form desired etching pattern on the target 32, and the etching depth is controlled by the voltage difference of the driver unit 4. Therefore, desired etching pattern can be formed on the substrate 31. To provide sufficient voltage difference between the cathode plate 2 and the anode plate 3, the separation between the anode mesh 6 and the anode plate 2 can be at least 100 mm or more.
Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have suggested in the foregoing description, and other will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.