基于丝网印刷技术的碳纳米管场发射冷阴极制作

制备了一种新型碳纳米管浆料,并总结了一套阴极制作工艺.实验表明,质量比约为10%的纯化碳纳米管、5%的纳米金属粉末和有机材料混合形成的印刷浆料,其阴极具有较好的发射均匀特性.在浆料制备过程中通过加入表面活性剂使碳纳米管分散更加均匀.用丝网印刷技术制作阴极,并用机械刀刻的办法制作阴、栅两极之间的沟槽,经烧结后分析阴极膜的电阻率和粘附性随阴极材料组分和制作工艺的变化关系,确定较为合适的升温曲线及丝网目数,阴极碳纳米管的均匀性、导电性的提高改善了发射均匀性.该阴极开启场为2.5 V/μm,在电场强度为3.3 V/μm下,阳极电流为5.6 μA,场发射电流稳定,波动小于5%.

Fabrication for Screen Printing Cold Cathode of Carbon Nanotube for Field Emission

A new type carbon nanotube (CNT) paste was prepared and the crafts to manufacture the cathode was also summarized .Experimental results show that the paste has an excellent emission performance when the metal powders weight fraction is about 5% while CNT is 10%.CNT can be separated much more uniform when added some surfactant .The cathode is fabricated with screen printing technique and the trench between cathode and gate is formed with a very thin knife edge.After the cathode film is sintered,its resistivity and adherence versus the weight (ratio) of each content in the slurry,as well as the process of manufacturing the cathode film,is analyzed.A reasonable heating process and silk screen aperture is made certainly.The cathode emitting uniform is improved through the enhancement of its electric conductivity and CNT uniformity.The turn-on field of the cathode is about 2.5 V/μm,the emitting current is 5.6 μA when the electric field reaches to 3.3 V/μm,and its fluctuation is less than 5%.