Stretching the limits of stretchable electronics

The quest for integrating intrinsically stiff and brittle electronics with the human body, which can be quite flexible and stretchable such as the skin, has resulted in a new and exciting field of ‘stretchable electronics’. The ground breaking biomedical applications include diagnostic surgical and diagnostic devices among others (Figure 1).

PhD Candidate 1: ir. S. Shafqat (Salman)
PhD Candidate 2: ir. S.M. Kleinendorst (Sandra)
Supervisor: dr.ir. J.P.M. Hoefnagels (Johan)
Promoter: prof.dr.ir. M.G.D. Geers (Marc)
Project Financing: STW
Project Period: February 2014 - February 2019

While a lot of research is being done in this field, typical solutions are limited to a reversible stretchability of approximately 50 %. Furthermore typically various exotic techniques are used for processing. In light of these limitations this project is set on two main goals. Firstly we aim to achieve an ‘ultra- stretchability’ of up to 500 %, which is required in applications such as balloon catheters and give a high factor of safety for typical applications. Secondly we restrict ourselves to proven and standard semiconductor processing techniques to ensure feasible large volume manufacturability.

The main project is composed of three sub-projects. Initially PhD candidate 1 (Salman Shafqat) and PhD candidate 2 (Sandra Kleinendorst) will be working on the development of highly stretchable interconnects, while later on a postdoc project will be setup to utilize this design to realize an inflatable ultrasound camera on top of a catheter as shown in Figure 2.  PhD candidate 2 is involved with the design and optimization of the geometry of these interconnects, which also involves utilizing finite element based modelling to study the mechanics of the interconnect structures. PhD candidate 1 is working on the development of techniques to test these highly sensitive structure at very small scales.