Material Technologies

In the topic "Material Technologies", we develop processes and technologies for the production of reusable silicon and germanium growth templates and for epitaxially grown silicon and germanium wafers or films. The detachment of the epitaxial layers is made possible by the electrochemical porosification of a mother substrate. In addition to the electrochemical etching parameters, the quality of the surface of the mother substrate plays a decisive role in the quality of the end product. Both purely chemical and chemical/mechanical processes can be used for preparation. After etching the multilayer porous layer into the substrate, a thermal reorganization takes place during which the surface of the porous layer closes and a mechanical predetermined breaking point is formed.  

Equipment and processes for the production of such growth templates for silicon and germanium are part of our excellent R&D infrastructure at Fraunhofer ISE. Our R&D activities cover the entire process sequence: substrate selection, surface preparation, porosification, healing and reorganization of the porous layer, epitaxial growth, surface definition, detachment of the films as well as various processes for gluing or bonding the films to cost-effective substrates. All these processes are developed with a view to achieving high throughputs and low costs while maintaining high material quality. Our customers are system manufacturers as well as precursor suppliers and users.


Fields of Work

In the research topic “Material Technologies” we focus on the following fields of work:

Epitaxy of Si and Ge and SiGe

Electrochemical Etching of Semiconductors

Surface Preparation and Lift-Off

R&D Infrastructure

At Fraunhofer ISE, we benefit from this infrastructure for our research and development activities:

  • Microelectronics CVD reactor for high-purity Si and Ge epitaxy for up to M6 substrates (PEPI)
  • Laboratory CVD reactors for Si epitaxy (RTCVD100 / RTCVD160)
  • Laboratory CVD reactor for SiC deposition (ZS-RTCVD)
  • Several wet chemistry laboratories for substrate preparation and defect etching
  • Electrochemical porosification systems for 4" to 300 mm round and 166x166 mm2
  • Tempering furnaces of various cleanliness classes (H2, Ar, N2
  • Surface definition and lift-off equipment
  • Optical microscopes for surface inspection, automatic defect analysis and coating thickness determination


Selected Research Projects



Development of Nano-Porous Silicon Layers in an Inline Process



High-Throughput Silicon-Based Films and Silicon Epitaxy