Institute of High Pressure Physics

This Sunday, November 3, will mark the start of the largest conference on nitride semiconductors, the 12th International Workshop on Nitride Semiconductors (IWN 2024).

The conference consists of five thematic symposia: Growth, Characterization/Physics, Optical and Optoelectronics, Electronic Devices, and Nanoscale. The Chair persons of the Growth symposium are Prof. Izabella Grzegory and Prof. Michal Boćkowski from our Institute.

The plenary lecture entitled. “Tunnel Junctions for Novel Nitride Optoelectronic Devices” will be given by Prof. Czeslaw Skierbiszewski, head of the MBE Epitaxy Laboratory of IWC PAN.

Two employees of the Institute have been asked to give invited papers: Prof. Henryk Turski will speak on “Epitaxy of III-Nitride Devices on Opposite Facets of the Same Polar Crystal: New Perspectives in Materials Engineering” and Dr. Tomasz Sochacki will talk about “Morphological Evolution During Bulk GaN Growth”. A number of other IWC PAN employees will also speak at the conference, presenting the results of their work on nitride semiconductors. Prof. M. Boćkowski will also appear as a panelist at the Rump Session entitled. “Future of III-Nitride Power Electronics”.

10th Workshop on Physics and Technology of Semiconductor Lasers was organized this year from 13 to 18 October, 2024 by our Institute in Sopot and chaired by prof. Piotr Perlin. It was a very successful meeting, gathering almost seventy participants with 62 presentations that included 14 invited talks, 29 contributed presentations and 19 posters. Thank you all for the fruitful discussions!

Next 11th Workshop on Physics and Technology of Semiconductor Lasers will be organized in 2026 by Lodz University of Technology, and chaired by prof. Tomasz Czyszanowski. We are all looking forward to it!

Dnia 9 października 2024 na Uniwersytecie Medycznym we Wrocławiu odbyła się międzynarodowa konferencja p.t. "Lasery w medycynie i stomatologii". Wykład inauguracyjny wygłosił prof. Witold Trzeciakowski z naszego Instytutu Wysokich Ciśnień PAN. Omówił on zalety laserów półprzewodnikowych i opisał wspólny projekt badawczy realizowany przez IWC PAN, Uniwersytet Medyczny we Wrocławiu oraz Warszawski Uniwersytet Medyczny. W tym projekcie IWC PAN dostarczał laserowe źródła światła niebieskiego, zielonego i czerwonego, a na uniwersytetach medycznych wykonywano badania (in vitro i kliniczne) z zastosowaniem tych laserów. Nowością było otrzymanie trzech długości fali lasera w światłowodzie co pozwalało na ciekawe badania oddziaływania promieniowania z tkanką. Projekt był przykładem owocnej współpracy interdyscyplinarnej, a jego efektem jest m. in. 9 publikacji w międzynarodowych pismach medycznych.

W trakcie konferencji dokonano przeglądu zastosowań laserów w dermatologii, urologii, okulistyce, stomatologii i chirurgii. Program dostępny jest pod linkiem. Wykład i całą konferencję można odsłuchać na YouTube. Wystąpienie prof. Witolda Trzeciakowskiego od 14 do 50 minuty nagrania.

Scientists from MBE Laboratory NL14 at the Institute of High Pressure Physics PAS (IHPP PAS, Unipress), in collaboration with groups at Cornell University (CU), have published the results of their recent study in Nature in a paper "Using both faces of polar semiconductor wafers for functional devices" by L. van Deurzen, E. Kim, N. Pieczulewski, Z. Zhang, A. Feduniewicz-Zmuda, M. Chlipala, M. Siekacz, D. Muller,  H.G. Xing, D. Jena, and H. Turski.

Demonstrated device is the first monolithic integration of a light source (light-emitting diode, LED) and a transistor (high electron mobility transistor, HEMT) on opposite sides of the same bulk semiconductor substrate. Therefore the authors introduce a term "dualtronics" to describe this concept and differentiate it from previous solutions.

By using a polar bulk GaN substrate - recognized as the highest-quality bulk GaN substrate available, also grown at Unipress - they were able to amplify the advantages of the devices by utilizing the built-in field inherent in the material. The monolithic integration of both devices on the same crystal enables the full utilization of the substrate's surface area and allows for denser packing of LED pixels.

Bulk crystal growth, surface preparation, dual-side epitaxial growth (schematically shown in the figure below), and initial characterization were all performed at IHPP PAS. Meanwhile, the dual-side processing of the LED and HEMT, microscopy characterization, and monolithic modulation of light emission from the LED by the HEMT were carried out at CU.

This work represents a promising starting point for the broader development of dual-side integrated optoelectronic and electronic devices, not only within the III-nitride material system.