Growth and characterization of GaN/AlGaN heterostructures on GaN substrate templates

This contribution will present the structural and optoelectronic properties of GaN/AlGaN heterostructures grown by Metal Organic Chemical Vapor Deposition (MOCVD) on GaN/sapphire templates. The target parameters for the materials heterostructures have been modeled for utilization in Avalanche Photodiode Detector Structures (APD) operating in the near and deep UV region. Optical modeling has improved absorption within the heterojunction as well as maximized light trapping within the device. Electronic modeling has determined the optimal dopant concentrations for maximum impact ionization rate, as well as tolerance to defects and unintentional doping. This application will require advances in the defect densities, surface morphology, and interfaces. Surface morphological and structural properties of GaN/AlGaN heterostructures are analyzed by Atomic Force Microscopy, Raman spectroscopy, and X-ray diffraction. The optoelectronic properties (phonon structures, free carrier concentrations, and carrier mobility) as well as layer thickness information, are determined by Fourier Transform Infrared Reflectance spectroscopy. A correlation of interfacial defects (type and concentration) with microscopic structural properties, surface morphology, and optoelectronic properties (free carrier concentration and high-frequency dielectric function) is discussed.

[1]  Martin Strassburg,et al.  Optical properties of n-doped Ga1−xMnxN epitaxial layers grown by metal-organic chemical-vapor deposition in mid and far (5−50 μm) IR range , 2008 .

[2]  G. Knoll.  Radiation Detection And Measurement, 3rd Ed , 2009 .

[3]  James Tweedie,et al.  Compensation effects in GaN:Mg probed by Raman spectroscopy and photoluminescence measurements , 2013 .

[4]  James Tweedie,et al.  Linear dependency of Al-mole fraction with group-III precursor flows in AlxGa1−xN (0≤x≤1) deposition by LP OMVPE , 2010 .

[5]  Alexander Franke,et al.  Correlation between mobility collapse and carbon impurities in Si-doped GaN grown by low pressure metalorganic chemical vapor deposition , 2016 .

[6]  James Tweedie,et al.  Point defect reduction in wide bandgap semiconductors by defect quasi Fermi level control , 2016 .

[7]  Oliver Ambacher,et al.  Defect structure of epitaxial GaN films determined by transmission electron microscopy and triple-axis X-ray diffractometry , 1998 .

[8]  Hao Jiang,et al.  All AlGaN epitaxial structure solar-blind avalanche photodiodes with high efficiency and high gain , 2016 .

[9]  Marko Zgonik,et al.  Refractive Index of III-metal-polar and N-polar AlGaN Waveguides Grown by Metal Organic Chemical Vapor Deposition , 2013 .

[10]  W. Martienssen,et al.  Springer handbook of condensed matter and materials data , 2005 .

[11]  Wei Lu,et al.  Carrier concentration and mobility in GaN epilayers on sapphire substrate studied by infrared reflection spectroscopy , 1999 .

[12]  N. Dietz,et al.  Real-time optical characterization of thin film growth , 2001 .

[13]  Melville P. Ulmer,et al.  Advances in UV sensitive visible blind GaN-based APDs , 2011, OPTO.

[14]  Hai Lu,et al.  Fine Control of the Electric Field Distribution in the Heterostructure Multiplication Region of AlGaN Avalanche Photodiodes , 2017, IEEE Photonics Journal.

[15]  Wonseok Lee,et al.  Kinetic study of Al-mole fraction in AlxGa1−xN grown on c-plane sapphire and AlN bulk substrates by metal-organic vapor-phase epitaxy , 2007 .

[16]  James Tweedie,et al.  The role of surface kinetics on composition and quality of AlGaN , 2016 .

[17]  Rafael Dalmau,et al.  Influence of gallium supersaturation on the properties of GaN grown by metalorganic chemical vapor deposition , 2008 .

[18]  Ashok K. Sood,et al.  AlxGa1−xN Ultraviolet Avalanche Photodiodes With Avalanche Gain Greater Than $10^{5}$ , 2015, IEEE Photonics Technology Letters.

[19]  D. Vasileska,et al.  Computational Electronics: Semiclassical and Quantum Device Modeling and Simulation , 2010 .