▎ 摘　　要

NOVELTY - The device has a metal electrode layer (20) arranged on a substrate (10). A copper layer (30) is arranged on the metal electrode layer. A copper sulfide nano wire layer (40) is installed on the copper layer. A graphene oxide layer (50) is arranged on the copper sulfide nano wire layer, where thickness of the metal electrode layer is about 150nm-250nm, nano wire range diameter of the copper sulfide nano wire layer is about 0.1-0.18 micro meter. The substrate is a glass substrate. The metal electrode layer is a molybdenum or cadmium metal electrode layer. USE - Field emission device for emitting X-ray. ADVANTAGE - The device has simple preparation, easy control, small volume, long service life, and excellent field emission performance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for field emission device manufacturing method. DESCRIPTION OF DRAWING(S) - The drawing shows a front view of a field emission device. Substrate (10) Metal electrode layer (20) Copper layer (30) Copper sulfide nano wire layer (40) Graphene oxide layer (50)