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Based theory of field emission vacuum microelectronic devices because of its small size, low power consumption, low-voltage, speed, anti-radiation and a wide range of working temperature and other significant features and much attention. The field emission cathode is a core of the vacuum microelectronic devices, its performance will directly determine the overall performance of the field emission device. Have made great progress in recent years through the continuous efforts of many researchers, the structure of the field emitter array cathode, the cathode material and the preparation process. Array of field emission cathode, the most widely used is the field emission sharp cone array, the prepared array of field emission cathode, the work function of the material, conductivity, density, thermal stability, chemical stability and other factors must be taken into its emission properties impact, taking into account the requirements of the materials processing. At present, the field emission cathode material varied, but there are a large work function, stability and uniformity is not ideal, the low emission performance aspects. In contrast, lanthanum hexaboride (LaB6) material having good thermal and chemical stability, having a low work function, a high electrical conductivity as well as the active cathode surface, and thus become prepared field emitter array cathode ideal material. Field emission array cathode preparation, more mature at this stage of the preparation of their own characteristics of molybdenum sharp cone field emission arrays the Spindt laboratory produced, and the process of oxidation sharpened silicon sharp cone field emitter array, two field emitter array cathode but not the same. They have in common is the use of silicon as a base material, the process is relatively simple and compatible with LSI technology, large-scale production. First experimental production the lanthanum hexaboride submicron gate aperture beak sharp cone field emitter array cathode using conventional Spindt type cathode Preparation of process based on this process using local oxidation of silicon process to prepare the gate insulating layer , and the successful use of the lateral oxidation of the silicon down to the sub-micron level of the gate aperture, through the fixed angle metallic aluminum was evaporated to prepare a sacrificial layer, an electron beam the vertical evaporation polycrystalline lanthanum hexaboride form a sharp cone cathode prepared a tip cone and the radius of curvature of 25nm lanthanum hexaboride sharp cone array of field emission cathode, the experiment found that this process, the biggest problem is the gate of a short-circuit between the cathode, in order to solve this problem, in the case of the structure unchanged carried out a large number of experiments can be prepared out gate between the cathode insulating good field emitter array cathode, but the experiments can be poor reproducibility, and easily short-circuited in the test. Experiment then uses another approach to preparing field emitter array cathode, it is a preparation process to prepare a sub-micron gate hole diameter lanthanum hexaboride field emitter array cathode using conventional Spindt type cathode field emitter array, and the preparation obtained cathode assembly and test. The thesis focused on the field emitter array cathode preparation process of the two structures, and etching process, vacuum coating process, field emission array cathode package, Burn-in and test key. Design field emission test device, test circuit, six of lanthanum boride field field emitter array cathode test, carried out a detailed analysis and discussion of experimental phenomena and data, pointed out the problems and propose improved methods.
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