Journal: ACS Applied Electronic Materials
Article Title: Miniaturized Micrometer-Level Copper Wiring and Electrodes Based on Reverse-Offset Printing for Flexible Circuits
doi: 10.1021/acsaelm.5c00230
Figure Lengend Snippet: (a) Individual 5 mm × 5 mm flexible IC test chip (Cu LO on the PEN substrate). (b) Optical micrograph of flexible IC test chip edge on PI substrate showing Cu NP (ht) line and contact pad pattern connected to screen-printed Ag electrodes after face-down assembly on a stretchable TPU substrate (c) with a full screen-printed Ag electrode pattern for characterization of the interconnection via contact pads (±I, ±V). (d) Flexible IC test chip from the Cu NP (ht) sample on a stretchable TPU substrate under bending stress.
Article Snippet: A sheet-fed reverse-offset printing system (Jemflex/Nihon Denshi Seiki) was used to print a Cu NP ink (CUNI-AC-01, Ishihara Chemical Co., LTD) and a poly-4-vinylphenol (PVPh)-based polymer resist ink on a 38-μm-thick PI substrate (Xenomax, Nagase) and a 125-μm-thick PEN substrate (Teonex Q 65HA, DuPont Teijin Films).
Techniques: