Spindt阴极制作中剥离层的研究  

Study of Lift-off Layers in Spindt Cathode Fabrication

作　　者：李兴辉[1] 白国栋[1] 李含雁[1] 丁明清[1] 冯进军[1] 廖复疆[1] 

机构地区：[1]中国电子科技集团公司第十二研究所微波电真空器件国家级重点实验室,北京100015

出　　处：《真空科学与技术学报》2013年第4期303-308,共6页Chinese Journal of Vacuum Science and Technology

基　　金：国家重点基础研究发展计划资助项目(No.2013CB933602)

摘　　要：在Spindt场发射阴极制作工艺流程中,剥离层对于形成良好的发射尖锥形状至关重要,同时它也是实现阴极阵列中尖锥均匀性的关键因素。本文研究了几种常用的剥离层材料包括金属铜,Al2O3以及水溶性的NaCl和Na2CO3。实验表明NaCl和Na2CO3用作剥离层,可以被去离子水迅速、容易地去除,并同时实现很好的腐蚀选择性。但用这些水溶性材料得到的发射尖锥形状不很规则且表面粗糙,由此也会带来整个阴极阵列上尖锥的不均匀性。使用Al2O3作为剥离层则较为理想,可以得到光滑的栅极收口和很好的尖锥阵列。但传统用来腐蚀Al2O3的热H3PO4,对于加热制作的Al2O3剥离层腐蚀较为困难。尝试了使用基于NaOH的腐蚀液来剥离加热Al2O3层,通过严格的工艺参数控制,如腐蚀液浓度和刻蚀时间,可以制作出质量较好尖锥发射体阵列。We addressed the advantages and disadvantages of the different lift-off layer materials, including copper, alumina, sodium chloride and sodium carbonate, used in Spindt cathode fabrication. The strengths of sodium chloride and sodium carbonate are rapid and easy peeling off by de-ionized（DI）water, and good etching selectivity,but its weaknesses include, irregularly shaped emitters with rough surface, and non-uniform emitter-army, because of re-crystallization of the materials. Alumina should be an ideal lift-off layer material because it makes smooth closure of the gate aperture and nice cone-shaped emitter array,except that it is rather diffcult to etch A1203 with hot phosphoric acid. To overcome this limita- tion, sodium hydroxide was used as an alternative etchant heated. Good cone-emitter arrays were fabricated by optimizing the etching conditions, such as the etchin time and etchant concentration.

关 键 词：Spindt阴极 剥离层 选择性腐蚀 水溶性材料 氧化铝 

分 类 号：TN405[电子电信—微电子学与固体电子学]