摘要
采用电化学腐蚀法并结合光刻、反应离子刻蚀以及碱性腐蚀等技术,在p型(100)硅基底中制备了大深宽比的二维大孔硅光子晶体,其二维周期性结构的晶格常数为3.8μm,孔隙直径约3.0μm,孔隙深度超过80μm.在光刻、反应离子刻蚀及碱性腐蚀所刻印的V形尖坑阵列的基础上,采用优化的电化学腐蚀参数能制备出周期性好、深宽比大、表/侧面光滑的高品质光子晶体结构,并从理论上利用数值模拟的方法证明了该样品结构在归一化频率位于0.162~0.205ωα/(2πc)范围内存在光子带隙.
Macroporous silicon with two-dimensional period icity is achieved by electrochemical etching in hydrofluoric-based electrolyte,using p-type doped (100) silicon substrate which is pre-patterned by the standard lithograpgy and alkaline ecthing.The structure shows perfect two-dimensional square crystal lattices with the lattices constant of 3.8μm,the pore diameters about 3.0μm and the high aspect ratio up to 30.The results show that the use of optimized parameters such as electrolyte and current density allows the fabrication of very hight quality samples with high aspect ratio and low roughness both at the surface and on the pore walls.And a photonic bandgap between 0.162~0.205ωa/(2πc) is identified by numerical results.
关键词
大孔硅
光子晶体
光子禁带
制备
碱性腐蚀
电化学腐蚀
macroporous silicon
photonic crystals
photonic bandgap
fabrication
alkaline etch
electrochemical-etch