Method for improving electron transmittance of electron source grid

The invention belongs to the technical field of vacuum microelectronics, and particularly relates to a method for improving the electron transmittance of an electron source grid, which comprises the following steps of: depositing electret materials on metal conductive layers on the surfaces and side walls of array units in a grid structure of an electron source, and leading out the metal conductive layers through leads; the electret material is charged to form an electret, the formation of the electret enables a focusing electric field to be generated among the array units of the grid mesh, and the formed focusing electric field can change the motion trail of electrons emitted by the arrayed cathode emitters; therefore, electrons emitted by the arrayed cathode emitter do not bombard the surface of the grid mesh and cross the grid mesh to be emitted out. According to the method, the electret material is deposited on the surface of the grid mesh, the motion trail of electrons emitted by the cathode is changed t