分别采用Cl2/Ar和SiCl4/Ar作为刻蚀气体对InAs/GaSb二类超晶格红外探测材料进行ICP(Inductively Couple Plasma)刻蚀。结果表明,两种刻蚀气体的刻蚀深度与刻蚀时间都呈线性关系;在2 mTorr气压下,RF功率为50 W,SiCl4流量为3 sccm,Ar为9 sccm时,刻蚀速率为100 nm/min,且与材料的掺杂浓度无关。实验还表明,SiCl4/Ar作为刻蚀气体时,Ar流量在很大范围内对刻蚀速率没用明显影响,但Ar的流量越大,刻蚀的均匀性越好;用Cl2/Ar作为刻蚀气体时,刻蚀速率也是100 nm/min,但Ar流量对刻蚀速率有影响:当Ar流量小于3 sccm时,刻蚀速率随Ar流量的减小而明显降低。
ICP(Inductively Couple Plasma) etching in InAs/GaSb type Ⅱ superlattice infrared detector material with Cl 2 /Ar and SiCl 4 /Ar were studied.The results show that the etching depth is linear with etching time for both etching gases.The etching rate is 100 nm/min at a set of conditions: RF power of 50 W,SiCl 4 flow for 3 sccm,Ar to 9 sccm,the standard operating pressure is 2 mTorr.The etching rate did not depend on the doping concentration.The Ar flow fluctuation has no significant effect on etching rate when using SiCl 4 /Ar as the etch gases.But this condition exists in Cl 2 /Ar,especially when the flow of Ar under 3 sccm,and the etching rate droped with the reduction of Ar flow.