Bulletin of ANPA

Abstract submitted to ANPA Conference July 14–16, 2023

Volume 5, Number 1

Condensed Matter Physics and Material Science

Abstract ID: ANPA2023-N00093

Abstract:

ANPA2023-N00093: Exploring Wide Bandgap Semiconductors in My Academic Journey from Banepa to Brooklyn

Authors:

• Mim Lal Nakarmi; Brooklyn College, Brooklyn, NY 11210

Wide bandgap materials with bandgap wider than 3 eV are technologically important materials for high temperature/power/frequency electronic devices, and for efficient light emitters. In this talk, I will discuss the progress and my contribution in the development of wideband gap materials, especially in III-nitrides for optical applications in the deep UV region during my Academic Journey from Banepa to Brooklyn._x000D_ _x000D_ Bandgap of AlGaN alloy can be increased systematically from ~ 3.4 to 6.1 eV by increasing aluminum content. AlGaN alloys of Al content > 60% is required for deep UV applications. A binary point in the nitride system, aluminum nitride (AlN), was chosen as the reference for the growth of Al-rich AlGaN alloys. Three-step growth technique was developed using the metal organic chemical vapor deposition to grow high quality AlN thin films on sapphire substrate. Growth of Al-rich AlGaN alloys has become a routine practice after the demonstration of reduced dislocation density of the materials when grown on AlN template. Achieving both n- and p-type conductivity is essential for optical devices such as light emitting diodes (LEDs). Increasing activation energy of the dopants with Al content and compensating point defects are challenges for enhancing conductivity in Al-rich AlGaN alloys. Heavy doping technique was used to achieve highly conductive n-type AlGaN by Si-doping. Recently, p-type AlGaN was also demonstrated in thin films grown on AlN bulk substrate by Mg-heavy doping._x000D_ _x000D_ In last decade, other materials such as zinc oxide, boron nitrides were also explored as alternative to the nitride. However, doping on these materials is still a challenge for reliable conductivity of both types. Thus, AlGaN alloy has become a unique material for deep UV applications. Recently, wide bandgap materials are also emerged as potential materials as host of single photon emitters. Current work on the h-BN materials and its atomic-like emissions will also be discussed.

To cite this abstract, use the following reference: https://anpaglobal.org/conference/2023/ANPA2023-N00093