This work was supported by the NSC-funded project (NSC93-2113M-492-003). The electron beam exposure and measurements were carried out using the facilities located in the National Nano Device Laboratories and National Chiao Tung University. The authors thank Dr. Chia-Hao Chan, Dr. Chih-Feng Huang, and Dr. Chih-Feng Wang in the Department of Applied Chemistry at the Chiao Tung University for their valuable suggestions and help with the experiment to clarify the mechanism of structural transformation in the zwitter-polymer.
Structural Transformation of Acrylic Resin upon Controlled Electron-Beam Exposure Yields Positive and Negative Resists†
Article first published online: 4 JUL 2005
Copyright © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Advanced Functional Materials
Volume 15, Issue 7, pages 1147–1154, July, 2005
How to Cite
Chen, J.-K., Ko, F.-H. and Chang, F.-C. (2005), Structural Transformation of Acrylic Resin upon Controlled Electron-Beam Exposure Yields Positive and Negative Resists. Adv. Funct. Mater., 15: 1147–1154. doi: 10.1002/adfm.200400077
- Issue published online: 4 JUL 2005
- Article first published online: 4 JUL 2005
- Manuscript Accepted: 15 FEB 2005
- Manuscript Received: 23 FEB 2004
- Lithography, electron-beam;
Zwitter polymers are defined as polymers that undergo transformation from a linear to a crosslinked structure under electron-beam irradiation. A resist polymer may be either linear or crosslinked, depending on electron-beam dosage. The structural transformation of acrylic resin make it suitable for applications in positive and negative resists in the semiconductor field. The contrast ratio and threshold dose both increase with increasing resist thickness for both the positive and negative resists, while the positive resist exhibits better contrast than the negative. The intensity of the characteristic Fourier-transform infrared absorption band at 1612 cm–1 (vinyl group) is used to explain the phenomena behind these resist transformations. We evaluate the effects of two important processing conditions: the soft baking and post-exposure baking temperatures. Pattern resolution decreases upon increasing the baking temperature, except for soft baking of the negative resist. The effect of electron dose on the pattern resolution is also discussed in detail for both resists. High electron-beam exposure does not improve the etching resistance of the resist because of the porous nature of the resist that develops after high-dosage irradiation.