8寸CMP设备对小尺寸镀铜InP晶圆的工艺开发  

Process development of small size copper-plated InP wafer with 8-inch CMP equipment

作　　者：成明 赵东旭[1] 王云鹏[1] 王飞[1] 范翊[1] 姜洋[1] CHENG Ming;ZHAO Dongxu;WANG Yunpeng;WANG Fei;FAN Yi;JIANG Yang(State Key Laboratory of Luminescence and Applications,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun130033,China)

机构地区：[1]中国科学院长春光学精密机械与物理研究所发光学及应用国家重点实验室,吉林长春130033

出　　处：《光学精密工程》2024年第3期392-400,共9页Optics and Precision Engineering

基　　金：国家重点研发计划资助项目(No.2022YFE0202300);吉林省与中国科学院科技合作高技术产业化专项资金资助项目(No.2022SYHZ0001);吉林省科技发展计划重点研发项目(No.20210201087GX,No.20210201001GX,No.2022007743)。

摘　　要：为了实现在8寸化学机械抛光设备上进行小尺寸镀铜InP晶圆的减薄抛光工作,提高设备的兼容性,缩减工艺步骤,减少过多操作导致InP晶圆出现裂纹暗伤和表面颗粒增加等问题,自制特殊模具,使小尺寸InP晶圆在8寸化学机械抛光设备上进行加工,再根据InP晶圆易碎的缺陷问题,通过调整设备的抛光头压力、转速和抛光垫的转速等相关工艺参数,使其满足后续键合工艺的相关需求。实验结果表明:在使用特殊模具下,当抛光头的压力调整为20.684 kPa、抛光头与抛光垫的转速分别为:93 r/min和87 r/min时,InP晶圆的表面粗糙度达到:Ra≤1 nm;表面铜层的去除速率达到3857×10^(-10)/min;后续与8寸晶圆的键合避免键合位置出现空洞等缺陷,实现2寸InP晶圆在8寸设备上的CMP工艺,大大降低了CMP工艺成本,同时避免晶圆在转移过程中出现表面颗粒度增加和划伤的情况,实现了InP晶圆与Si晶圆的异质键合及Cu互连工艺。To achieve the thinning and polishing of small-size copper-plated InP wafers using 8-inch chemi⁃cal mechanical polishing(CMP)equipment,it's essential to enhance equipment compatibility,streamline process steps,and mitigate issues like cracks and surface particles on InP wafers due to excessive han⁃dling.Initially,employing custom-made molds allows the processing of small-size InP wafers on 8-inch CMP equipment.Subsequently,to address the brittleness of InP wafers,adjusting the equipment's polish⁃ing head pressure,speed,and polishing pad speed,among other process parameters,is crucial to satisfy the demands of the subsequent bonding process.Experimental validation shows that with the use of special molds and the polishing head pressure set to 20.684 kP,along with polishing head and pad speeds of 93 r/min and 87 r/min, respectively, the InP wafer's surface roughness achieves Ra≤1 nm, and the copper lay⁃er's removal rate is 3 857×10^(-10)/min. This preparation ensures defect-free bonding with 8-inch wafers,eliminating voids at the bonding interface. The CMP process for 2-inch InP wafers on 8-inch equipmentsignificantly lowers CMP costs, prevents the increase in surface particle size and scratches during wafertransfer, and facilitates hybrid bonding and Cu interconnections between InP and Si wafers.

关 键 词：化学机械抛光 磷化铟 去除速率 键合 表面粗糙度 

分 类 号：TN405[电子电信—微电子学与固体电子学]