【作者】 田业冰；

【导师】 邢玉生； 康仁科；

【作者基本信息】 大连理工大学 ， 机械设计及理论， 2005， 硕士

【摘要】 随着集成电路(IC)制造技术的飞速发展,为了增大IC芯片产量,降低单元制造成本,硅片趋向大直径化。随着硅片直径增大,为了保证硅片具有足够的强度,原始硅片的厚度也相应增加,与此相反,为满足IC芯片封装等需要,使芯片厚度逐渐减薄。硅片直径和厚度的增大以及芯片厚度的减小使半导体加工面临许多突出的技术问题:硅片直径增大后,表面质量要求更为严格,并且加工中翘曲变形,加工精度不易保证;原始硅片厚度增大以及芯片厚度的减薄,使硅片背面减薄加工的材料去除量增大,提高加工效率成为一个亟待解决的问题。随着硅片尺寸的不断增大,超精密磨削特别是自旋转磨削成为了大尺寸硅片加工的有效方法。目前正逐步代替传统硅片加工工艺中的研磨、腐蚀等工艺,应用于大直径硅片加工中的材料制备阶段和图形硅片的背面减薄。 本文建立了硅片自旋转磨削的运动几何学模型,分析了磨削参数与磨削纹理的关系,并对磨粒磨削运动轨迹进行了计算机仿真和预测;在运动学模型的基础上,推导了磨粒轨迹长度、磨纹数量以及磨削稳定周期的公式,并分析了磨粒轨迹对表面质量的影响关系。通过硅片磨削实验,对硅片磨削表面纹理的计算机仿真结果和理论分析结果进行了验证。 在反转法的原理上,建立了硅片自旋转磨削材料去除率的理论模型,推导了材料去除率公式,分析了磨削工艺参数与材料去除率的关系。 以VG401MKⅡ型超精密磨床为试验平台进行了磨削工艺试验,研究了磨削工艺参数、砂轮粒度对硅片磨削材料去除率、砂轮主轴电机驱动电流以及磨削后硅片表面粗糙度的影响,提出了提高磨削表面质量和加工效率的工艺措施。 研究结果为提高硅片超精密磨削的表面质量以及材料去除率,提供系统的加工理论和有效的工艺措施,对于实现大尺寸硅片高精度超光滑表面的高效低损伤磨削加工具有重要指导意义。更多还原

【Abstract】 With faster developing of integrated circuits (IC) manufacturing technology, the diameter of silicon wafer trends to be larger in order to increase the yields of chips and decrease the cost per bit And at the same time, the thickness of the prime wafer is also increased to ensure the strength of the wafer. Contrarily, the chip thickness is decreased to meet the requirements of IC package and improve the heat radiation properties of the chip. With the increase of the diameter and thickness of wafer and reduce of chip thickness, the process of wafer is facing many new technology. The high machining accuracy and quality is difficult to achieve because large size wafer is easy to warp. And the high machining efficiency is required because size changes of the wafer and the chip result in the increase of the material removal amount Among the precision process methods, the wafer rotation grinding method is considered as the most promising technology for processing the large scale silicon wafer, which has used in both manufacturing of the silicon wafer media and back thinning of the pattern wafer.In this paper, a kinematics geometry model of the wafer rotation grinding is established. The relationship between grinding marks and the grinding parameters is analyzed. The cutting trajectories of grits on the wafer are predicted by computer simulation. Based on the theoretical model, the length of trajectory, number of grinding marks and grinding stable period are deduced. The relationship between grinding surface quality and the density of grinding marks is theoretically analyzed. The results of computer simulation and theoretical analyses are verified by comparing with the results of experiments, which are conducted on a VG401MKII grinding machine.By the principle of reversal process, the formula of material removal rate (MRR) in wafer rotation grinding process is deduced. The relationship between MRR and the grinding parameters is given.A series of process experiments of wafer grinding are carried out on a VG401MKII grinding machine. The influence of the grit size and the process parameters, including the rotational speed of the cup grinding wheel, the down feed rate of the grinding wheel spindle and the rotational speed of the chuck table, on MRR, spindle motor current and roughness, areanalyzed. The grinding process parameters are proposed to improve grinding efficiency and surface quality on ground wafer.The result provides theory basis and available technique ways to improve the surface quality, increase material removal rate. The study is also propitious to realizing high efficient, ultra-precision and low damage grinding.更多还原