ISBN 9783843941914

978-3-8439-4191-4, Reihe Optik

Piotr Cegielski
Development of Integrated Perovskite Lasers for Dielectric Photonic Circuits

182 Seiten, Dissertation Rheinisch-Westfälische Technische Hochschule Aachen (2019), Softcover, A5

Zusammenfassung / Abstract

Silicon nitride photonics is progressing towards becoming one of the major photonic integration technologies. This is thanks to the integrability into CMOS (complementary metal oxide semiconductor) back-end-of-line (BEOL) and usability over a broad spectral range from visible to infrared wavelengths. In recent years common photonic components, including active devices such as modulators and photo detectors, have been monolithically integrated into this platform. Laser sources are an exception.

In this dissertation this problem is addressed via development of monolithically integrated CMOS compatible laser sources using solution-processed metal-halide perovskite semiconductors as a gain medium. Metal halide-perovskites are a class of solution-processed direct band-gap semiconductors, which can be deposited by low-cost methods such as spin coating and annealing at temperatures below 100 ∘C. Unfortunately, their highly ionic nature makes them sensitive to the chemistry used in standard microfabrication processes such as optical lithography, without which their potential for integrated optoelectronics is very limited. In this work such standard processes are modified so that the degradation of the perovskite layer is avoided, which enabled the fabrication of perovskite ring and disc lasers integrated with silicon nitride photonic circuits.

This is the first demonstration of use of optical lithography in patterning of metal halide perovskites. The threshold of the optically pumped disc lasers fabricated within this work is the current record for CMOS compatible integrated semiconductor laser. Furthermore, it is lower than the thresholds of similar devices made of both III-V semiconductors and most of the discrete lasers made of similar unprocessed perovskites. By enabling the fabrication of integrated perovskite microdevices the technology presented in this thesis is an important milestone in the field of perovskite optoelectronics. Furthermore, these results are equally important for further development of integrated photonics.