Laser‐Induced Forward Transfer: A Digital Approach for Printing Devices on Regular Paper

Abstract

Inkjet printing (IJP) is the most widespread direct‐write technique in paper electronics. However, this technique cannot be used for printing devices on untreated regular paper, since its low‐viscosity nanoinks leak through the cellulose fibers. Thus, a planarization coating is frequently used as a barrier, even though this makes substrates more expensive and less eco‐friendly. Alternatively, high solid content screen printing (SP) inks could allow printing on regular paper due to their high viscosity and large particle size; however, they cannot be printed through IJP. Another digital technique is then required: laser‐induced forward transfer (LIFT). This work aims at proving the feasibility of LIFT for printing devices on regular paper. The main transfer parameters are systematically varied to obtain uniform Ag‐SP interconnects, whose performance is improved by a multiple‐printing approach. It results in low resistances with much better performance than those typical of IJP. After optimizing the functionality of the printed lines, a proof‐of‐concept consisting of a radio‐frequency inductor is provided. The characterization of the device shows a substantially higher performance than that of the same device printed with IJP ink in similar conditions, which proves the potential of LIFT for digitally fabricating devices on regular paper.

RETRACTED: Digital printing technology and its application in packaging printing

“…Digital printing technology can be applied to label proofing and mass production, and the quality of label can be guaranteed. 8 With the help of digital printing equipment, network technology and remote control, staff can transfer label samples to different devices for synchronous printing, which greatly improves the printing efficiency. At the same time, the digital printing label can also provide the corresponding anti-counterfeiting logo, so that consumers can identify the authenticity of products through the label information, which is particularly important in books, medicine, cosmetics and other products.…”

Printed Electronics Technologies for Additive Manufacturing of Hybrid Electronic Sensor Systems

“…In general, it has proven to be compatible with a large variety of substrates, even untreated regular paper. [181,182] One advantage of LIFT over the most prominent digital noncontact printing technology, namely inkjet printing, is the possibility to deposit micro-sized particles. For printed electronics applications this can be highly favorable, as it enables the digital deposition of screen-printing ink to achieve highly conductive patterns.…”

“…In general, it has proven to be compatible with a large variety of substrates, even untreated regular paper. [ 181,182 ]…”

Laser-Induced Forward Transfer: A Method for Printing Functional Inks

“…However, most of the commercial conductive circuits are still printed by screen-printing [115], because the high solid content of the ink results in sheet-resistance values two order of magnitude below those obtained with inkjet inks. As said before for cell printing, the high viscosity (some Pa•s) and large particles of these inks are not a limitation for LIFT [35,77,78,117,118].…”

“…Any defect, like a single discontinuity or any protuberance, compromises the performance of the full device. Accordingly, conductive inks are mainly involved in most of the LIFT studies dealing with the printing of continuous patterns [35,65,66,[71][72][73][74][75][76][77][78]. Nevertheless, studies on continuous line and homogeneous area printing have been also conducted with water-based suspensions in view of their interest in biosensors fabrication [79,80].…”