A Simple and Scalable Fabrication Method for Organic Electronic Devices on Textiles

Summary

In this paper, we present a protocol to selectively deposit organic materials on textiles, which allows for the direct integration of organic electronic devices with wearables. The fabricated devices can be fully integrated in textiles, respecting their mechanical appearance and enabling sensing capabilities.

Abstract

Today, wearable electronics devices combine a large variety of functional, stretchable, and flexible technologies. However, in many cases, these devices cannot be worn under everyday conditions. Therefore, textiles are commonly considered the best substrate to accommodate electronic devices in wearable use. In this paper, we describe how to selectively pattern organic electroactive materials on textiles from a solution in an easy and scalable manner. This versatile deposition technique enables the fabrication of wearable organic electronic devices on clothes.

Introduction

The field of wearable electronics is a fast-growing market expected to be worth 50 billion euros in 2025, over three times the current market. The main challenge facing current wearable devices is that intrusive solid electronic attachments limit the usage of established devices in wearable systems. Using textiles that are already present in everyday life is a very attractive and straightforward approach to avoid this limitation. Due to its elastic capability, some parts of the clothing that we wear are naturally in tight contact with the skin. Many examples of smart clothes available on the market today are based on thin, plastic displays, keyboards, and light source....

Protocol

1. Patterning Conducting Polymers on Textile

1. Fix a 10 cm x 10 cm textile sheet on a planar surface for easy handling during the process. For the textile, use a 100% interlock knit polyester fabric with a thickness of 300 µm and a knit direction stretch capability up to 50%.
2. To make a mask containing the patterning design, use a 125 µm-thick polyimide film; an example of the pattern is illustrated in Figure 1.
   1. Use a laser cutter (e.g., Protolaser S, LPKF) to pattern the polyimide mask¹⁰; the pattern design of an electrode is illustrated in Figure 1.

Results

Traditional methods for applying colors or patterns to textiles rely on removable masking layers to allow the selective deposition of dyes. In Figure 1, we show the adaptation of such an approach to the patterning of PEDOT:PSS electrodes on textiles. As a masking layer, we used hydrophobic polydimethylsiloxane, which can restrain the non-controllable diffusion of the aqueous PEDOT:PSS solution. Moreover, the softness and stretchability of knitted and woven textiles can be.......

Discussion

The patterning of conducting materials is one of the first steps in the fabrication of functional electronic devices. This can become challenging, as the fabrication process needs to take into account the chemical and physical properties of such materials, and the process flow needs to consider the material cross-compatibility between the fabrication steps. In the microfabrication of organic electronic devices, these two aspects are even more significant due to the highly reactive nature of organics. Today, however, orga.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
SYLGARD 184, Silicone elastomer kit (Base and Curing agent)	Dow Corning		PDMS elastomer
The conducting polymer formulation
CleviosTM PH 1000 PEDOT:PSS	Heraeus		Conductive polymer
Ethylene glycol	Sigma-Aldrich	03750-250ML	Solvent (EG), CAS: 107-21-1
3-methacryloxypropyltrimethoxysilane	Sigma-Aldrich	M6514	Cros linker (GOPs), CAS: 2530-85-0
4-dodecylbenzenesulfonic acid	Sigma-Aldrich	44198	DBSA; CAS: 121-65-3
The ionic liquid gel
UV lamp DFE 2340	C.I.F/ ATHELEC	DP134	UV-365 nm
1-Ethyl-3-methylimidazolium ethyl sulfate	Sigma-Aldrich	51682-100G-F	Ionic Liquid (IL), CAS: 342573-75-5
Poly(ethylene glycol) diacrylate	Sigma-Aldrich	455008-100ML	Mn 700, CAS: 26570-48-9
2-Hydroxy-2-methylpropiophenon	Sigma-Aldrich	405655-50ML	Phot Initiator (PI), CAS: 7473-98-5
The textile fabric	VWR	Spec-Wipe 7 Wipers	100% interlock knit polyester fabric
The polyimide film	DuPont	HN100	Polyimide film with 125 µm thickness