Development of High Performance EUV Light Source Using Condensed Cone-center-axis Plasma Generated by Laser with Nano-second Pulse-power

利用纳秒脉冲功率激光产生的聚光锥中心轴等离子体开发高性能 EUV 光源

• 批准号: 17360161
• 负责人: NAKANO Motohiro
• 金额: $ 10.11万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17360161/
• 关键词: Semiconductor production; Extreme-ultraviolet (EUV); Plasma; Laser; Pulse-power; デバイス設計・製造プロセス; パルス放電

To create a future system of extreme-ultraviolet (EUV) lithography for 45nmhp semiconductor production, an innovative light source with 13.5nm wavelength is demanded very high power over 115W at intermediate focus and long operation life at a high repetition rate over 7kHz. Recently, to generate EUV, two methods have been developed with laser produced plasma (LPP) and discharge produced plasma (DPP). Tin target has significant potential for high conversion efficiency at 13.5 nm of Sn spectrum peaks. In this study, we propose a new method to develop high performance EUV light source by using holed Sn target. When a pulse laser is irradiated to the conical hole, high density plasma can be generated to its center-axis. This condensed plasma is excited into high temperature by focused laser with nano-second pulse power and then emits the light with shorter wavelength including EUV. This light can be collected through the open hole at the backside. After this emission, this cone-center-axis plasma is cooling and becomes debris that is a serious problem in the EUV source. Using this holed target, the debris is remarkably decreased toward its backside. EUV emission through its hole is narrow directivity. For commercial EUV light source, repetitive use of the target is required. We irradiated holed targets repeatedly and measured EUV intensity through the holes. After the laser was irradiated several times, EUV intensity is approximately stable. This result suggests that this target can be used repeatedly. After the experiment, the irradiated cone was changed to cylindrical hole. Therefore, We measured the EUV intensity from new cylindrically holed target and obtained the maximum value of total EUV emission from the outlet of the hole. Our targets have other advantages for repetitive use and reducing debris from the outlet of the hole.

为了创建用于45nmhp半导体生产的未来极紫外（EUV）光刻系统，需要具有13.5nm波长的创新光源，该光源在中间焦点处具有超过115W的非常高的功率，并且在超过7kHz的高重复率下具有长的工作寿命。最近，为了产生极紫外光，已经开发了两种方法：激光产生等离子体（LPP）和放电产生等离子体（DPP）。锡靶具有在13.5nm的Sn光谱峰处获得高转换效率的显著潜力。在本研究中，我们提出了一种新的方法来开发高性能的EUV光源，通过使用有孔的锡靶。当脉冲激光照射锥形孔时，在其中心轴上产生高密度等离子体。这种凝聚的等离子体被纳秒脉冲功率的聚焦激光激发到高温，然后发射出包括EUV在内的较短波长的光。这种光可以通过背面的开孔收集。在该发射之后，该锥形中心轴等离子体冷却并变成碎片，这是EUV源中的严重问题。使用这种有孔靶，碎片朝向其背面显著减少。通过其孔的EUV发射是窄方向性的。对于商业EUV光源，需要重复使用靶。我们反复照射有孔的靶，并通过孔测量EUV强度。经过多次辐照后，EUV强度基本稳定。这一结果表明，该目标可以重复使用。实验结束后，将受照圆锥改为圆柱孔。因此，我们测量了新的圆柱孔靶的EUV强度，并获得了孔出口处的总EUV辐射的最大值。我们的靶材具有重复使用和减少孔出口碎屑的其他优势。

项目成果

Development of High Performance EUV Light Source by Laser Produced Plasma-Target Design and Evaluation of EUV Conversion Efficiency-

通过激光产生等离子体开发高性能 EUV 光源 - 靶材设计和 EUV 转换效率评估 -

• 发表时间: 2006
• 期刊: Extended Abstracts of International 21st Century COE Symposium on Atomistic Fabrication Technology
• 作者: T.Yoshikawa;Y.Otani;M.Nakano;T.Kataoka;H.Inoue;Y.Oshikane
• 通讯作者: Y.Oshikane

高輝度レーザプラズマEUV(Extreme-ultraviolet)光源の開発-ターゲット設計と特性評価-

高亮度激光等离子体EUV（极紫外）光源的开发 - 靶材设计及特性评价 -

• 发表时间: 2006
• 期刊: 2006年度精密工学会秋季大会学術講演会 講演論文集
• 作者: 吉川隆弥;大谷祐子;中野元博;片岡俊彦;井上晴行;押鐘 寧
• 通讯作者: 押鐘 寧

高性能レーザプラズマEUV(Extreme-ultraviolet)光源の開発-ターゲット構造とEUV変換効率の評価-

高性能激光等离子体EUV（极紫外）光源的开发 - 靶材结构和EUV转换效率的评估 -

• 发表时间: 2006
• 期刊: 2006年度精密工学会秋季大会学術講演会 講演論文集
• 作者: 中野元博;吉川隆弥;大谷祐子;片岡俊彦;井上晴行;押鐘 寧
• 通讯作者: 押鐘 寧