InAs/GaSb超晶格台面刻蚀工艺研究综述

Research Review of InAs/GaSb Superlattice Mesa Etching Process

本文综述了InAs/GaSb超晶格台面刻蚀工艺研究。从湿法和干法刻蚀的物理化学机理以及参数调控等方面进行分析,旨在阐明工艺条件对台面形貌的影响,以抑制带隙较窄的长波和甚长波超晶格表面漏电流。结果表明,湿法刻蚀中恰当的腐蚀液配比可以实现两种组分的均匀性刻蚀,而不会导致粗糙的表面和严重的下切;干法刻蚀中,采用Cl_(2)基和CH 4基混合气体,通过调整刻蚀气体类型及比例可实现物理和化学刻蚀两个过程的平衡,保证台面侧壁平滑性和倾角的垂直度。另外,对于不同组分的超晶格,需要选择不同的工艺参数才能满足InAs和GaSb的协同性刻蚀。最后对InAs/GaSb超晶格台面刻蚀工艺作出了展望。

This paper reviews the research on InAs/GaSb superlattice mesa etching technology.The physicochemi-cal mechanism and parameter control of wet and dry etching are analyzed to elucidate the influence of process conditions on mesa morphology,so as to suppress the surface leakage current of long wave and very long wave superlattice with narrow band-gap.The results show that the uniform etching of the two components can be achieved with the appropriate proportion of etching solution in wet etching,without causing rough surface and serious undercut.In dry etching,Cl_(2)-base and CH 4-base mixed gas is used.By adjusting the type and proportion of etching gas,the balance between physical and chemical etching processes can be achieved to ensure the smoothness of the mesa sidewall and the perpendicularity of the dip angle.In addition,for superlattices of different components,different process parameters need to be selected to meet the synergistic etching of InAs and GaSb.Finally,the InAs/GaSb superlattice mesa etching process is prospected.