Title :
GeSn Heterojunction LEDs on Si Substrates
Author :
Oehme, Michael ; Kostecki, Konrad ; Arguirov, Tzanimir ; Mussler, Gregor ; Kaiheng Ye ; Gollhofer, Martin ; Schmid, Maurizio ; Kaschel, Mathias ; Korner, Roman Alexander ; Kittler, M. ; Buca, Dan ; Kasper, Erich ; Schulze, J.
Author_Institution :
Inst. for Semicond. Eng., Univ. of Stuttgart, Stuttgart, Germany
Abstract :
GeSn on Si light-emitting diodes (LEDs) is investigated for different Sn concentrations up to 4.2% and they are compared with an LED made from pure Ge on Si. The LEDs are realized from in-situ doped pin junctions in GeSn on Ge virtual substrates. The device structures are grown with a special ultra-low temperature molecular beam epitaxy process. All LEDs clearly show direct bandgap electroluminescence emission at room temperature. The light intensity of the compressively strained GeSn LEDs increases with higher Sn concentration. The in-plane strain of the LEDs is determined with reciprocal space mapping. The bandgap energies of the emitting GeSn layer are calculated from the emission spectra.
Keywords :
electroluminescence; elemental semiconductors; energy gap; epitaxial layers; germanium; germanium compounds; integrated optics; light emitting diodes; molecular beam epitaxial growth; p-i-n diodes; photonic band gap; semiconductor doping; silicon; substrates; Ge; GeSn; Si; bandgap electroluminescence emission; bandgap energies; device structures; emission spectra; germanium virtual substrates; heterojunction LED; in-plane strain; in-situ doped pin junctions; light intensity; reciprocal space mapping; room temperature; silicon light-emitting diodes; silicon substrates; temperature 293 K to 298 K; ultralow temperature molecular beam epitaxy process; Light emitting diodes; Molecular beam epitaxial growth; Photonic band gap; Silicon; Strain; Substrates; Tin; GeSn; Si photonics; electroluminescence; germanium; light emitting diode;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2013.2291571
