有蜡贴片工艺对4英寸SiC抛光片几何参数的影响  

Influence of Wax Mounting Process on Geometry Parameters of 4-inch SiC Polishing Wafer

作　　者：高飞[1] 李晖[1] 张弛[1] Gao Fei;Li Hui;Zhang Chi(The 46th Research Institute,CETC,Tianjin 300220,China)

机构地区：[1]中国电子科技集团公司第四十六研究所,天津300220

出　　处：《半导体技术》2020年第8期638-644,共7页Semiconductor Technology

摘　　要：研究了单面抛光中有蜡贴片工艺对抛光后4英寸(1英寸=2.54 cm)SiC晶片总厚度变化(TTV)和翘曲度的影响。分别选择固体蜡和液体蜡进行贴片实验,采用平面度测量仪检测加工前后晶片的TTV和翘曲度,采用数显千分表测量贴片及单面抛光后晶片表面5点厚度的变化。发现采用液体蜡贴片时,加工晶片的TTV较好,蜡层的均匀性是影响晶片TTV的主要原因,蜡层厚度均匀性差会使晶片TTV变差,同时也会使晶片发生不规则的形变。并且分析了旋涂参数对液体蜡蜡层均匀性的影响。结果表明,在滴蜡时间为2.3 s、低速旋转速度为700 r/min、低速旋转时间为6 s、高速旋转速度为3000 r/min、高速旋转时间为7 s的条件下,贴片表面5个点的厚度偏差小于2μm,加工晶片的TTV小于5μm。The influences of wax mounting process in single side polishing on the total thickness variation(TTV)and warpage of the 4-inch(1 inch=2.54 cm)SiC wafer after polishing were studied.The mounting experiments were carried out by using solid wax and liquid wax,respectively.TTV and warpage of the wafers before and after processing were measured by using a flatness measuring instrument,and the thickness variation of five points on wafers was measured by using a digital display dial gauge after moun-ting and single side polishing.It is found that the TTV of the wafers is better when mounting by liquid wax and the uniformity of the wax layer is the chief factor affecting the TTV of wafers.Poor thickness uniformity of the wax layer may make the TTV of the wafers worse and also cause irregular deformation of the wafer.The influence of spin parameters on the uniformity of the liquid wax layer was analyzed.The results show that the thickness deviation of the five points on the wafer surface after mounting is less than 2μm and the TTV of the processing wafer is less than 5μm under the conditions of the dispensing time of 2.3 s,low-speed rotation speed of 700 r/min,low-speed rotation time of 6 s,high-speed rotation speed of 3000 r/min and high-speed rotation time of 7 s.

关 键 词：有蜡贴片工艺 SiC晶片 总厚度变化(TTV) 翘曲度 液体蜡 

分 类 号：TN304.2[电子电信—物理电子学] TN305.1