【作者】 李钢；

【导师】 孙清清； 顾以理；

【作者基本信息】 复旦大学 ， 集成电路工程（专业学位）， 2014， 硕士

【摘要】 光刻工艺是半导体制造中最为重要的工艺步骤之一。主要作用是将掩膜板上的设计图形传输到硅片上去,从而为下一步进行刻蚀或者离子注入工序做好阻挡层,其原理和照相机类似。光刻的成本大约占整个硅片制造工艺的1/3左右,耗费时间约占整个硅片工艺的40-60%。同时光刻机是生产线上最贵的机台,8寸代工厂的光刻机就已达到5-15百万美元/台。最主要的成本是在成像系统(由15-20个直径为200-300mm的透镜组成)和定位系统(定位精度小于10nm)。透镜的工艺精度要求非常高,而且有专门的公司生产。于此同时其折旧速度非常快,折合下来大约3-9万人民币/天,而且随着工艺节点的越先进,其成本越高,所以也称之为印钞机。光刻部分的主要机台包括两部分：轨道机(Tracker),用于涂胶显影以及烘烤；扫描曝光机(Scanning)。光刻工艺的要求为,光刻机台需要具有有高的分辨率；光刻胶具有高的光学敏感性；准确地对准；低的缺陷密度等。同时对于代工厂来说,由于客户成本,功耗等原因,需要不断的降低关键尺寸(CD, criditle-dimensions),因此在即0.13um,0.1 lum工艺相继量产后,研发9Onm工艺变为重中之重, 本文目的在于整理在90nm工艺研发过程中遇到的一些问题和挑战以及解决方法,为将来更小关键尺寸研发提供参考及借鉴。 同时,即使是90nm工艺,很多layer并不要求90rnm左右CD, 出于成本和产能考量, 大部分layer可以在DUV(248n m波长)以及MUV(365nm波长)生产,但是有一些layer用MUV甚至DUV也无法满足量产需求, 因此,引进了ArF(193nm波长)机台用于这些对CD要求比较高的layer量产,同时由于DUV及MUV有很多工艺已经可以参考,难度主要集中在ArF相关layer以及引入中的一些问题(主要是OVL相关), 因此,本文主要讨论ArF相关layer和OVL的讨论。更多还原

【Abstract】 Photolithography, also termed optical lithography or UV lithography, is a process used in micro fabrication to pattern parts of a thin film or the bulk of a substrate. It uses light to transfer a geometric pattern from a photo mask to a light-sensitive chemical "photo resist", or simply "resist," on the substrate. A series of chemical treatments then either engraves the exposure pattern into, or enables deposition of a new material in the desired pattern upon, the material underneath the photo resist.Photolithography shares some fundamental principles with photography in that the pattern in the etching resist is created by exposing it to light, either directly (without using a mask) or with a projected image using an optical mask. This procedure is comparable to a high precision version of the method used to make printed circuit boards. Subsequent stages in the process have more in common with etching than with lithographic printing. It is used because it can create extremely small patterns (down to a few tens of nanometers in size), it affords exact control over the shape and size of the objects it creates, and because it can create patterns over an entire surface cost-effectively. Its main disadvantages are that it requires a flat substrate to start with, it is not very effective at creating shapes that are not flat, and it can require extremely clean operating conditions.And to foundry, because of cost and power consumption, the CD is always need to be reduced, thus after the mass production of 0.13um,0.11um, the development of 90nm has been of paramount importance.The major contribution of this dissertation is to summarize the problems and challenges during the 90nm development and how to solve it, it would be benefit to smaller CD process development. Meanwhile, most of the layers do not need 90nm CD in 90nm process, consider of cost and capacity, most of the layers could production at DUV(248nm) and MUV(365nm), but some of the layer could not mass production at MUV or DUV, thus, the ArF(193nm) is needed for these high CD requirement layers production, and as most difficult is from ArF related layers and OVL issue, thus this dissertation will focus on ArF related layer and OVL issue discussion.更多还原