

- Warsaw-4-PhD School
- Doctoral studies
Events
IHPP PAS Seminar on Nitride Semiconductors![]() Dear Ladies and Gentlemen, We are pleased to invite you to the IHPP PAS Seminar on Nitride Semiconductors. The presentation will be held in a hybrid mode – at the seminar room in New Technologies building, Al. Prymasa Tysiąclecia 98, and through Zoom platform (to get the link, please contact us at nitride_seminar@mail.unipress.waw.pl ). The next seminar is scheduled on Monday 11.12.2023 at 14:00. Speaker: Prof. Matthew P. Halsall (Department of Electrical and Electronic Engineering, University of Manchester) Title: Electrical and Optical Spectroscopies applied to point and extended defects in Wurtzite and Cubic Nitride semiconductors. Abstract: Link Sincerely, Tadeusz Suski Two new LIDER laureates at Unipress. Congratulations!![]() We are happy to share that dr inż. Tomasz Sochacki and dr inż. Marta Sawicka are the laureates of a LIDER Program funded by National Center for Research and Development (NCBiR).
Congratulations! The final ranking list of projects qualified for funding in the 14th competition of the LIDER Program is available on the website of the National Center for Research and Development. Bidirectional light-emitting diode dedicated to alternating current operation![]() Gallium nitride-based light-emitting diodes are the most energy-efficient light sources. Despite their clear advantages, they require a direct current (DC) power supply to operate effectively, while the power grid is built on alternating current (AC). An interesting proposal for a new class of optoelectronic devices dedicated to direct AC operation has been proposed by Mikołaj Żak together with colleagues from the Laboratory of Molecular Beam Epitaxy (NL-14) and other researchers of the Institute of High Pressure Physics PAS (IHPP PAS). In a paper published in Nature Communications (Impact Factor 16.6), they present a bidirectional light-emitting diode (BD LED) that emits light in both directions of current flow through the device, unlike conventional LEDs, which must be forward biased. It is possible due to the special epitaxial structure of the BD LED, in which the active region is surrounded on both sides by tunnel junctions from the p-type doped regions. This ensures that electrons and holes are effectively injected into the same quantum well above the turn-on voltages under both negative and positive bias. The paper "Bidirectional light-emitting diode as a visible light source driven by alternating current" (M. Żak, et al. Nat Commun 14, 7562 (2023)) is an important part of the upcoming PhD thesis of M.Sc. Mikołaj Żak and is the result of many years of research on tunnel junctions in GaN undertaken by the NL-14 group of IHPP PAS. Oferta pracy na stanowisku Asystent/-ka Dyrektora![]() Instytut Wysokich Ciśnień Polskiej Akademii Nauk poszukuje kandydatów na stanowisko: Asystent/-ka Dyrektora. |
DLTS studies of AlGaN![]() Nitride based materials still suffer from the lack of the understanding of the mechanisms of defects formation and their impact on the material properties. Dr Piotr Kruszewski with his collaborators from NL12 laboratory recently used deep-level transient spectroscopy (DLTS) to study AlxGa1-xN (x<0.05) grown by MOVPE. It was shown that the electron emission signal related to the FeGa (0/-) acceptor level splits into individual components due to aluminum fluctuations in the second-nearest neighbor (2NN) shell around the FeGa impurity atoms. The calculations of the probability of finding a given number of aluminum atoms in the 2NN shell of the FeGa defect agreed well with the experimental concentrations determined from Laplace DLTS peak intensities. This finding shows that in dilute AlxGa1-xN layers grown by MOVPE, aluminum and iron atoms are randomly distributed in the material. Finally, it was demonstrated that the energy level of the FeGa acceptor with no Al atoms in the 2NN shell in the AlxGa1-xN samples shifts linearly with the aluminum content. The publication "Alloy splitting of the FeGa acceptor level in dilute AlxGa1−xN" (P. Kruszewski et al., Appl. Phys. Lett. 123, 222105 (2023)) is the result of the collaboration with colleagues from the Photon Science Institute and Department of Electrical and Electronic Engineering, the University of Manchester cooperating in NCN-OPUS project lead by Dr. Piotr Kruszewski. Fig.1. Three-dimensional diagram of the AlxGa1-xN alloy showing two shells of atoms surrounding the FeGa impurity (top image) and Laplace DLTS spectra for the FeGa acceptor state in AlxGa1-xN (x ≤ 0.05) samples with energy-level-difference values at X axis (bottom image). OPUS 25 i PRELUDIUM 22![]() Narodowe Centrum Nauki (NCN) opublikowało wczoraj listy rankingowe projektów zakwalifikowanych do finansowania w konkursach OPUS 25 i PRELUDIUM 22. Są tam dwa projekty z naszego Instytutu:
Gratulujemy! Warto zauważyć, że w tym roku rekordowo mało projektów mogło uzyskać dofinansowanie. Wskaźniki sukcesu wynosiły zaledwie 8% i 10.7% dla OPUS i PRELUDIUM, więc były dwa razy niższe niż przed dwoma laty. Prof. Krzysztof Jóźwiak, Dyrektor NCN, podkreśla, że absolutnie konieczne jest zwiększenie budżetu NCN na finansowanie badań podstawowych w kolejnych latach.
Strong Polish representation at ICNS-14 in Fukuoka, Japan![]() This year the largest conference on nitride semiconductors – ICNS-14 was held in Japan, in Fukuoka on November 12-17, 2023. There were 53 participants from Poland (51 presentations), with over 25 participants from Unipress (Institute of High Pressure Physics PAS) who contributed with 35 scientific presentations on the research carried out in our Institute. More than half of the Polish contributions at ICNS-14 came from our Institute. We take pride in showcasing Poland's expertise in nitride semiconductors! Our young talents demonstrated exceptional performance. Three of our doctoral students honored for delivering the best presentations: Muhammed Aktas, Piotr Jaroszynski, and Kacper Sierakowski received Best Student Awards for their oral presentations. Presentation statistics at ICNS-14 (credit: ICNS-14 program) SPIE Photonics West 2024![]() SPIE Photonics West is world’s largest photonics technologies event. Scientists from our Institute will contribute to the SPIE Photonics West 2024, Gallium Nitride Materials and Devices XIX conference that will take place from 29 January to 1 February 2024 in San Fransisco (USA). The Program can be browsed here. Note that Unipress has 3 invited papers (all by female researchers) and 5 oral presentations. |
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