Si-TaSi2共晶自生复合材料由于具有较低的功函数、良好的电传输特性和自生三维肖特基结等特点,被认为是具有良好应用前景的场致发射材料之一。依据选择性腐蚀的原理,把电子束区熔技术制备的Si—TaSi2共晶自生复合材料制作为Si—TaSi2场发射阴极阵列。对影响选择性腐蚀工艺的两个因素:腐蚀时间和腐蚀液配比进行了系统的研究。研究表明,随着腐蚀时间的延长,TaSi2尖锥的曲率半径减小,长径比增大;制备Si-TaSi2场发射阴极阵列的最佳腐蚀液配比是浓硝酸和浓氢氟酸的体积比v(HNO3):v(HF)=4:1,最佳的腐蚀时间是20~30min。采用透明阳极法对制备的Si—TaSi2阴极阵列进行了场发射性能的测试,结果表明该腐蚀工艺制作的Si—TaSi2阴极阵列有较好的场发射性能。
Si-TaSi2 eutectic in situ composite has been regarded as one of the promising field emission materials due to relatively low work function, good electricity conductivity and three-dimensional array of Schottky junctions grown in the composite spontaneously. The Si-TaSi2 field emitter arrays were fabricated according to the selective corrosion theory. Moreover, the two important factors i. e. corrosion time and ingredient of the corrosive which affected corrosion process most were systematically investigated. It was found that the curvature radius rc was decreased and the height and aspect ratio h/rc of the TaSi2 fibers were increased with the increase of the corrosion time. The optimal ingredient of the corrosive was v(HNO3) : v(HF)=4 : 1, and the optimal corrosion time was about 20-30min. A transparent anode technique was adopted to study the field emission property of the Si-TaSi2 eutectic in situ composites. It was found that this material has better field emission properties.