Fabrication of a Flexible Photodetector Based on a Liquid Eutectic Gallium Indium.

Peng Xiao,Hyun-Jong Gwak,Soonmin Seo

doi:10.3390/ma13225210

Abstract

A fluidic gallium-based liquid metal (LM) is an interesting material for producing flexible and stretchable electronics. A simple and reliable method developed to facilitate the fabrication of a photodetector based on an LM is presented. A large and thin conductive eutectic gallium indium (EGaIn) film can be fabricated with compressed EGaIn microdroplets. A solution of LM microdroplets can be synthesized by ultrasonication after mixing with EGaIn and ethanol and then dried on a PDMS substrate. In this study, a conductive LM film was obtained after pressing with another substrate. The film was sufficiently conductive and stretchable, and its electrical conductivity was 2.2 × 106 S/m. The thin film was patterned by a fiber laser marker, and the minimum line width of the pattern was approximately 20 μm. Using a sticky PDMS film, a Ga2O3 photo-responsive layer was exfoliated from the fabricated LM film. With the patterned LM electrode and the transparent photo-responsive film, a flexible photodetector was fabricated, which yielded photo-response-current ratios of 30.3%, 14.7%, and 16.1% under 254 nm ultraviolet, 365 nm ultraviolet, and visible light, respectively.

Highlights

A fluidic gallium-based liquid metal (LM) is an interesting material for flexible and stretchable electronics and has received much attention from researchers owing to its extraordinary electrical conductivity and outstanding mechanical properties [1,2,3,4]
We introduce a simple and reliable method to fabricate a flexible and transparent photodetector based on an LM
LM based on gallium alloys (EGaIn) was used for the device

Summary

Introduction

A fluidic gallium-based liquid metal (LM) is an interesting material for flexible and stretchable electronics and has received much attention from researchers owing to its extraordinary electrical conductivity and outstanding mechanical properties [1,2,3,4]. It is known that various materials have been utilized for manufacturing flexible and stretchable electronics [5,6,7]. These materials are not flexible and stretchable in the bulk state and need to be treated further. LM has a fluidic nature at room temperature and has potential for various applications in stretchable electronics.

Methods

Results

Discussion

Conclusion