Int. J. Nanomanufacturing, Vol. 6, Nos. 1/2/3/4, 2010 219 Copyright © 2010 Inderscience Enterprises Ltd. Improvement of two-photon induced photoreduction by using a metal ion solution with a high concentration of silver ions Yong Son, Tae Woo Lim and Dong-Yol Yang* Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Science Town, Daejeon 305-701, Republic of Korea E-mail: sonyong@kaist.ac.kr E-mail: ltwalways@kaist.ac.kr E-mail: dyyang@kaist.ac.kr *Corresponding author Prém Prabhakaran and Kwang-Sup Lee Department of Advanced Materials, Hannam University, 461-6 Junmin-Dong, Yuseong-Gu, Daejeon 305-811, Republic of Korea E-mail: premchem@gmail.com E-mail: kslee@hnu.kr Jocelyne Bosson Laboratoire de Physique Fondamentale et Appliquée, Université d’Abobo-Adjamé, 02 BP 801Abidjan 02, Côte d’Ivoire E-mail: bosson@uabobo.ci Olivier Stéphan and Patrice L. Baldeck Laboratoire de Spectrométrie Physique, Université Joseph Fourier, CNRS (UMR 5588), BP 87, 38402 Saint Martin d’hères Cedex, France E-mail: olivier.stephan@ujf-grenoble.fr E-mail: patrice.baldeck@ujf-grenoble.fr Abstract: Fabrication of three-dimensional metallic microstructures is an important issue for various applications in electronics and nanophotonics. Precise metallic micropatterns were fabricated by the two-photon induced photoreduction (TPPR) process. The process employs the photoreduction of silver ions in a metal ion solution composed of silver nitrate (AgNO 3 ) and water-soluble polymer (poly(4-styrenesulfonique acid)). To improve the resolution and the uniformity of metallic micropatterns, a metal ion solution with a high concentration of silver ions was used, and the continuous forming window (CFW) of fabrication conditions was obtained by considering the mechanism of TPPR and heat effects during the process. Through this work, continuous silver lines and micropatterns with a minimum width of 560 nm were fabricated and their quality was verified.