Michael quirk_半导体制造技术-第15章_光刻_光刻胶显影和先进的光刻技术.ppt

Semiconductor Manufacturing TechnologyMichael Quirk Julian Serda ? October 2001 by Prentice HallChapter 15 Photolithography: Resist Development and Advanced Lithography Objectives After studying the material in this chapter, you will be able to: 1. Explain why and how a post exposure bake is done for conventional and Chemically amplified DUV resist. 2. Describe the negative and positive resist development process for conventional and chemically amplified DUV resist. 3. List and discuss the two most common resist development methods and the critical development parameters. 4. State why a hard bake is done after resist development. 5. Explain the benefits of a post-develop inspection. 6. List and describe the four different alternatives for advanced lithography, including the challenges for introducing each alternative into production. 7. Describe and give the benefit for the advanced resist process of top surface imaging. Eight Basic Steps of Photolithography Post Exposure Bake Deep UV Exposure Bake Temperature Uniformity PEB Delay Conventional I-Line PEB Amine Contamination of DUV Resist leading to “T-top” Formation Reduction of Standing Wave Effect due to PEB Develop Negative Resist Positive Resist Development Methods Resist Development Parameters Photoresist Development Problems Negative Resist Crosslinking Development of Positive Resist Development Methods Continuous Spray Development Puddle Development Resist Development with Continuous Spray Puddle Resist Development Resist Development Parameters Developer Temperature Developer Time Developer Volume Normality Rinse Exhaust Flow Wafer Chuck Hard Bake Characteristics of Hard Bake: Post-Development Exposure Evaporates Residual Solvent in Photoresist Hardens the Resist Improves Resist-to-Wafer Adhesion Prepares Resist for Subsequent Processing Higher Temperature than Soft Bake, but not to Point Where Resist Softens and Flows Resist Hardening with Deep UV Softened Resist Flow at High Temperature Develop Ins