Institute of High Pressure Physics

Dear Ladies and Gentlemen,

We are pleased to invite you to the IHPP PAS Seminar on Nitride Semiconductors. The next presentation will be held in a hybrid mode – at the New Technologies seminar room, 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 12.06.2023 at 14:00.

Speaker: dr inż. Paweł Prystawko (IHPP PAS, NL-12)

Title: Compensation control of n-type GaN using intrinsic Carbon from TMGa precursor in MOVPE growth for Vertical GaN Power Devices

Abstract:

There is intrinsic residual doping with carbon in MOVPE grown GaN due to presence of carbon in organic precursor chemicals TMG and TEG. Usually n-type layers and unintentionally doped layers grown in standard growth conditions result in carbon incorporation as high as 10^17cm-3. It has been demonstrated that, if carbon content approached silicon donor value, an abrupt drop of electron mobility is observed. We investigated non-standard growth conditions to promote fast methyl radical elimination with active hydrogen originating from decomposed ammonia and resulted in reduction of carbon doping. These are: high growth pressure, high temperature as well as control of supersaturation by means of high V/III group ratio. It allows to reduce residual carbon doping below 1 x 10^16cm-3.

Sincerely,

Tadeusz Suski
Piotr Perlin
Anna Kafar

"Jaszowiec 2023" conference gathers the semiconductor physics community in Poland since more than 50 years. "Jaszowiec 2023" is a short name for the „51st International School & Conference on the Physics of Semiconductors”. This year it is organized in Szczyrk from 17 to 23 June, 2023 and our Institute is one of co-organizers.

The Conference is preceded by a 2-days tutorial session (School), addressed mainly to graduate students and young scientists. This year prof. Michał Boćkowski will give one of the lectures in this tutorial session entitled „Bulk GaN growth”. Other physicists from our Institute will also present their research results.

More about the Jaszowiec conference at www.jaszowiec.edu.pl

In the NL-1 Laboratory of Plastic Deformation under High Pressure, we plastically deform polymer materials. We demonstrated a significant increase in mechanical properties of polyamide 6 (PA6) after hydrostatic extrusion.

In our recently published paper we explain the phenomena and propose strengthening mechanisms occurring in polymeric materials during high pressure plastic deformation. Read more in „Structural Hierarchy of PA6 Macromolecules after Hydrostatic Extrusion” Materials 16, 3435 (2023).

Figure. Schematic of changes in the fracture structure of PA6 samples before and after the hydrostatic extrusion (HE process). After the HE process, the spherulites have the shape of bars arranged in a regular manner parallel to each other.

New lecture on crystal growth theory and application of machine learning for advanced modeling of crystal growth processes of semiconductor bulk crystals and epitaxial layers will be given within the scope of the physics courses in spring semester of Warsaw4PhD School.

The 8-lecture course will be given on-line by dr Akira KUSABA from Kyushu University. The first lecture will be given on April 18th 2023 at 10.00 am.

Visit the Warsaw4PhD webpage to find out more about the scope of the new course and get the Zoom meeting link.