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 29.05.2023 at 13:00.

Speaker: dr inż. Joanna Moneta (IHPP PAS, NL-12)

Title: Peculiarities of the strain relaxation in InGaN layers

Abstract:

The idea of using relaxed InGaN layers as pseudo-substrates for the growth of InGaN-based devices has emerged in the last years. While most of approaches of gaining relaxed InGaN are based on the elastically relaxed layers obtained by preparation of compliant layer (e.g., porous GaN) and subsequent patterning, in our attempt we focus on InGaN layers relaxed plastically by the introduction of misfit dislocations. An understanding of the dislocation formation process which allows prediction and control of the properties of relaxed InGaN layers is essential for achieving good quality InGaN/GaN templates.
InGaN layers with indium content close to 20% deposited on various types of (0001)-GaN substrates were studied. The growth was carried out by either Molecular Beam Epitaxy (MBE) or Metalorganic Vapor Phase Epitaxy (MOVPE). Structural analysis was done by means of transmission electron microscopy, cathodoluminescence imaging, traditional X-ray diffractometry and full-field X-ray diffraction microscopy.
The seminar will discuss the mechanisms of misfit dislocations nucleation and glide and the influence of GaN-substrate misorientation on the strain relaxation process. The impact on the structural properties of InGaN/GaN templates will be addressed.

Sincerely,

Tadeusz Suski
Piotr Perlin
Anna Kafar