Kim Geumtaek, Kwon Daeil
School of Mechanical, Aerospace, and Nuclear Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
Department of Systems Management Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea.
J Nanosci Nanotechnol. 2021 May 1;21(5):2987-2991. doi: 10.1166/jnn.2021.19136.
Along with the reduction in semiconductor chip size and enhanced performance of electronic devices, high input/output density is a desired factor in the electronics industry. To satisfy the high input/output density, fan-out wafer-level packaging has attracted significant attention. While fan-out wafer-level packaging has several advantages, such as lower thickness and better thermal resistance, warpage is one of the major challenges of the fan-out wafer-level packaging process to be minimized. There have been many studies investigating the effects of material properties and package design on warpage using finite element analysis. Current warpage simulations using finite element analysis have been routinely conducted with deterministic input parameters, although the parameter values are uncertain from the manufacturing point of view. This assumption may lead to a gap between the simulation and the field results. This paper presents an uncertainty analysis of wafer warpage in fan-out wafer-level packaging by using finite element analysis. Coefficient of thermal expansion of silicon is considered as a parameter with uncertainty. The warpage and the von Mises stress are calculated and compared with and without uncertainty.
随着半导体芯片尺寸的减小和电子设备性能的提升，高输入/输出密度成为电子行业所期望的一个因素。为满足高输入/输出密度，扇出型晶圆级封装已引起广泛关注。虽然扇出型晶圆级封装具有若干优点，如厚度更低和热阻更好，但翘曲是扇出型晶圆级封装工艺需要尽量减小的主要挑战之一。已有许多研究使用有限元分析来探究材料特性和封装设计对翘曲的影响。当前使用有限元分析进行的翘曲模拟通常是在确定性输入参数下进行的，尽管从制造角度来看参数值是不确定的。这种假设可能导致模拟结果与实际结果之间存在差距。本文通过使用有限元分析对扇出型晶圆级封装中的晶圆翘曲进行不确定性分析。将硅的热膨胀系数视为具有不确定性的参数。计算了有不确定性和无不确定性情况下的翘曲和冯·米塞斯应力并进行比较。
