Surface Silanization of Polyimide for Autocatalytic Metallization
- PDF / 1,870,478 Bytes
- 9 Pages / 593.972 x 792 pts Page_size
- 6 Downloads / 203 Views
https://doi.org/10.1007/s11837-020-04286-2 Ó 2020 The Minerals, Metals & Materials Society
INTERFACIAL STABILITY IN MULTI-COMPONENT SYSTEMS
Surface Silanization of Polyimide for Autocatalytic Metallization JUN-NAN LIU,1 MANIK CHANDRA SIL,1 RUI CHENG,2 SHIEN-PING FENG,2 and CHIH-MING CHEN 1,3,4 1.—Department of Chemical Engineering, National Chung Hsing University, Taichung 402, Taiwan. 2.—Department of Mechanical Engineering, The University of Hong Kong, Pok Fu Lam, Hong Kong. 3.—Innovation and Development Center of Sustainable Agriculture (IDCSA), National Chung Hsing University, Taichung 402, Taiwan. 4.—e-mail: [email protected]
Due to its superior chemical stability, mechanical strength, light weight, and flexibility, polyimide (PI) has been widely used as a polymeric substrate of flexible printed circuit boards such as flexible copper clad laminates (FCCLs). The development of an adhesiveless dual-layer structure is imperative for the application of FCCLs in globalized 5G consumer electronics. In this work, autocatalytic metallization on a silane-grafted PI film was developed to fabricate a high-quality Cu/PI substrate. PI was functionalized by amine-terminated organosilanes to load polyvinylpyrrolidone-capped Pd nanoclusters (PVP-nPd) as a catalyst. The effects of organosilanes with different numbers of amine functional groups on the adsorption of the PVP-nPd catalyst and the subsequent metallization of Cu were systematically investigated. Comprehensive surface characterizations were carried out on the PI films before and after silanization. The organosilane bearing three amine groups was found to outperform its counterpart with one amine group, exhibiting a fourfold increase in catalyst adsorption, which also improved the metallization efficiency.
INTRODUCTION Flexible electronics have received much attention in versatile applications such as wearable electronics, portable devices, and point-of-care biosensors.1–4 Due to their specific features of a low dielectric constant, high thermal stability, and superior corrosion resistance,5–7 polyimide (PI) is widely used as the carrier material for printed circuitry. Conventionally, a flexible copper clad laminate (FCCL) is fabricated by laminating a Cu foil onto a PI film, and an epoxy adhesive is used to enhance the interfacial adhesion. The lamination side of the Cu foil is usually roughened to increase the contact area for adhesion. However, this trilayer FCCL structure may not be suitable for advanced high-frequency (5G) applications in which a low-profile Cu foil is needed to reduce high-speed signal loss due to the skin effect.8,9 In addition, the removal of the thick epoxy adhesive layer (10– 20 lm) is inevitable to meet the miniaturization trend of microelectronic devices. Therefore, the
(Received April 26, 2020; accepted July 5, 2020)
development of new technology to meet the abovementioned requirements is urgent to produce a reliable and adhesiveless Cu/PI substrate. Bottom-up deposition of a metal film on a PI substrate by surface activation and f
Data Loading...
