Substrate technology

Simulation of stretched substrate with rigidized areas
© Fraunhofer ISC
Simulation of stretched substrate with rigidized areas.

For future applications in displays or other macro-electronic devices, free-form factors are more and more important aiming for 3D-shaped displays, foldable or stretchable devices. Substrates play an important role in order to combine foldable and stretchable areas with rigid areas that are still necessary since the majority of high functional materials cannot be converted to stretchable or flexible materials.

CeSMA has developed a technology to rigidize areas on stretchable substrates on a µ-scale by a UV lithographic approach. Base of this technology is a profound know-how in elastomeric substrates.

Stretchable display substrate
© Fraunhofer ISC
Photomicrograph: Stretchable Display-substrate with µm-scaled areas (circles) rigidized by UV lithography.

The modification of these substrates towards locally rigidizable substrates works by the combination of PDMS technology and ORMOCER® technology. The rigidization factor is about 10 – 20 in Young’s Modulus and the overall stretchability is still at > 50 % when half of the area is increased in mechanical values (compared to substrates of a stretchability of 200 % when rigidization is not applied).

Beside of this fine pitch of alternating soft and rigid areas, the technology provides a mechanical gradient in a µm-scale that increase the long-term-stability of the substrate. The mechanical values of the individual positions do not change over time and the substrates are highly transparent.

Our competences

  • Highly adjusted, multifunctional elastomeric substrate materials (PDMS base)
  • Substrate manufacturing (small scale)
  • Local Definition of mechanical values by UV lithographic approach
  • Extending the substrate properties by adding further additives

Our offer

  • Mechanical, chemical and optical investigation of alternating substrates with a local resolution < 100 µm
  • Development of substrates specified by customer/partners
  • Feasibility studies