Title :
Characterization of InAlAs solar cells grown by MOVPE
Author :
Smith, Brittany L. ; Hellstroem, Staffan D. ; Nelson, George T. ; Bittner, Zachary S. ; Slocum, Michael A. ; Forbes, David V. ; Hubbard, Seth M.
Author_Institution :
Rochester Inst. of Technol., Rochester, NY, USA
Abstract :
Epitaxial layers of InAlAs are prime candidates for the top cell in triple-junction photovoltaics (PV). Growth conditions during metalorganic vapor phase epitaxy (MOVPE) of InAlAs affect the material properties and subsequently the device characteristics of the epilayers. Impurity concentrations in InAlAs epilayers grown under various conditions are analyzed by secondary-ion mass spectrometry (SIMS) in order to assess impurity incorporation. Deep-level transient spectroscopy (DLTS) is used to assess the energy level and concentration of carrier traps. The effect of defects (traps) on the device characteristics are modeled with a Sentaurus simulation. Devices were fabricated and tested in a solar simulator before and after contact etch. Spectral response (SR) and electroluminescence (EL) are also measured. Final experimental results showed an efficiency of 9.74% without an antireflective coating.
Keywords :
III-V semiconductors; MOCVD; antireflection coatings; deep level transient spectroscopy; electroluminescence; indium compounds; secondary ion mass spectroscopy; solar cells; vapour phase epitaxial growth; InAlAs; MOVPE; SIMS; antireflective coating; carrier traps; deep level transient spectroscopy; electroluminescence; epitaxial layers; material properties; metalorganic vapor phase epitaxy; secondary ion mass spectrometry; solar cells; spectral response; top cell; triple junction photovoltaics; Aluminum; Carbon; Indium phosphide; Integrated circuit modeling; MATLAB; Resistance; III–V semiconductor materials; InAlAs; OMVPE; photovoltaic cell; semiconductor impurities;
Conference_Titel :
Photovoltaic Specialist Conference (PVSC), 2014 IEEE 40th
Conference_Location :
Denver, CO
DOI :
10.1109/PVSC.2014.6925125
