OSE Dissertation Defense by Mr. Fatih Furkan Ince on MBE Growth of Sb based alloys using interfacial misfit arrays for MWIR devices

Departmental News

Mr. Fatih Furkan

Posted: February 10, 2024

Date: Friday, February 23, 2024

Time:  2:30 PM Mountain Time (US and Canada) 

Location: CHTM, Room #103

Dissertation Committee:

Dr. Ganesh Balakrishnan, EPSCoR Director and Electrical and Computer Engineering Department - Committee Chair

Dr. Sang Han, Chair, Chemical and Biological Engineering

Dr Sadhvikas Addamane, Sandia National Labs

Dr. Thomas Rotter, Research Professor, CHTM


Mid-wave infrared (MWIR) detectors are essential for various applications such as medical devices, remote sensing, and spectroscopy. In the MWIR detection,  antimonide-based narrow bandgap semiconductors are ideal due to their stronger bonding compared to II-VI’s and better spatial uniformity, scalability and lower cost. InSb infrared focal plane arrays are extensively utilized due to their cut off wavelength of 5.3μm and the operation wavelength can be extended to long-wave infrared (LWIR) spectrums using type-II superlattices such as InAs/InAsSb or bulk InAsSb grown metamorphic buffers. However, the absence of suitable binary substrates between 6.09 Å and 6.47 Å has led to the exploration of metamorphic buffers using InGaSb and AlInSb ternary alloys. In the literature, antimonide based step graded and linearly-graded buffers are widely studied. Metamorphic buffers often require thicknesses over 4μm to achieve the desired lattice constant, which involves challenges in repeatability and cost-efficiency for III-V based MWIR detectors. To create cost-effective and easily manufacturable III-V based MWIR detectors, interfacial misfit dislocation (IMF) arrays can be used to achieve fully relaxed buffers for a lattice constant of interest for antimonide alloys.

In this dissertation, the impact of mismatch strain on the relaxation mechanism of antimonide alloys grown on commercially available substrates such as InAs and InP is investigated. The dominant strain relief mechanism is analyzed using HR-TEM to gain a comprehensive understanding of the formation of misfits in these alloys. A change in relaxation with the effective misfit dislocation type linked to the mismatch between the epilayer and the substrate is indicated by X-ray diffraction (XRD) and reciprocal space mapping of these epilayers. Finally, the quality of these buffers compared to the latest findings is to be compared. This research allows the creation of a broader understanding of ternary alloys grown on binary substrates using this method.



Fatih received his bachelor's degree in Astronautical Engineering from Istanbul Technical University in 2016. He also pursued a minor in Physics with a special focus on Optics. He is now a PhD student at the University of New Mexico Optical Science and Engineering program. Since December 2019, Fatih has been working on Molecular Beam Epitaxial growth of III-V materials focusing on mismatched epitaxy of antimonides for infrared devices. He will join Stanford University as a post-doctoral researcher starting in April 2024.