Ge Quantum Dots-Based Light Emitting Devices

• Published in: Photonics and Electronics with Germanium pp. 233 - 266
• Main Authors: Xu, Xuejun, Maruizumi, Takuya, Shiraki, Yasuhiro
• Format: Book Chapter
• Language: English
• Published: Germany John Wiley & Sons, Incorporated 2015; Wiley; Wiley‐VCH Verlag GmbH & Co. KGaA
• Subjects: current‐injected light emitting diodes; germanium (Ge) self‐assembled quantum dots; photonic crystal cavity; silicon photonics; silicon‐based light emitter; standing‐wave‐type resonator; traveling‐wave‐type resonator
• ISBN: 9783527328215; 3527328211
• DOI: 10.1002/9783527650200.ch11

The communication traffic in the Internet is exploding fast, and demands for higher transfer and processing speeds require extremely high power consumption. A crucial component in silicon photonics is the light source; however, silicon‐based light emotter is still under development due to the inherent property of indirect band gap of silicon (Si). This chapter first reviews, the formation of germanium (Ge) self‐assembled quantum dots (QDs) on Si substrate and their lumonescent properties, and then describes the fabrication process and performance of light emotting devices composed of Ge QDs and a small optical cavity. Two types of optical cavities are included, one of which is the standing‐wave‐type resonator such as a photonic crystal (PhC) cavity. The other is the traveling‐wave‐type resonator such as a mocrodisk/mocroring resonator with whispering gallery resonance mode. Finally, state‐of‐the‐art current‐injected light emotting diodes (LEDs) with Ge QDs embedded in PhC nanocavities and mocrodisks are discussed in detail.