Fabrication of Embedded Copper Wire on Glass by Laser-Induced Chemical Liquid Phase Deposition with Ytterbium Fiber Laser

Abstract

Glass possesses a lot of useful and attractive properties such as transparency, stability, and strength. For these properties, especially transmittance, glass is one of widely used materials in many industrial fields, such as mechanics, biology, medical science and engineering. However, glass is well-known as non-conductive and non-flexible material. Therefore, many attempts and researches have been done for making circuits on the glass. Since lots of deposition techniques have been widely studied such as electroless laser deposition, chemical deposition with hot plating and electronical method, those methods rarely contributed to increase usability of deposited glass due to durability, weak adhesion problems and so forth. In this study, copper deposition has been processed inside of channel by laser to overcome existing disadvantages. LIBWE, which enables to machine glass easily regardless of glass physical properties, has been conducted to make channels before deposition process. After the channels has been machined, the substrate is transferred to LCLD solution and laser beam initiate the deposition along the channels. Depth of 50 µm and various width (50 ~ 150 µm) of channels are filled with copper. With this process, disadvantages from previous studies such as lack of controllability, usability and durability are solved by generation of embedded copper wires. Furthermore, resistance can be controlled and further applications such as stacking and sealing are possible.

일반적으로 유리는 다양한 특성을 가지고 있음에도 전도성을 가지고 있지 않아 활용에 제약이 있었다. 이에 전도성 물질을 도포하거나 증착하는 기술들은 많이 소개가 되어 있지만, 실사용에 있어서는 여러가지 이유로 잘 사용되지 못하였다. 이에 본 연구는 기존 유리에 대한 구리 증착 기술의 한계점인 내구성 및 접착성 대해서 지적하고 이를 극복하기 위한 조합공정을 제시하였다. 레이저 후면 식각 공정으로 유리를 미세가공한 후, 레이저 구리증착 공정을 통해, 깊이 50 µm와 다양한 폭 (50 ~ 150 µm)의 미세가공물 내부에 구리를 증착하는 데에 성공하였다. 그 과정에서 증착된 구리는 내구성 증대, 저항 조절성 확보 등을 특징으로 보였으며, 조합공정 효과에 대해 실험적으로 증명하였다. 더욱이 조합공정 결과물을 통해 유리 기반 회로, 다층 구조 회로 등의 가능성을 제시하였다.