Towards white light laser emission based on strained Poly:(Si/Ge)

Abstract

Solubility of Sn in Ge has the most impact in the emission characteristics of direct band gap GeSn alloy. Here, we employed the metal induced crystallization (MIC) process of amorphous Ge and Si via Sn as a novel mechanism to incorporate Sn inside Ge and Si networks. (Al/Si/Sn/Ge/Sn) and (Al/Ge/Sn/Ge/Sn) multilayers are deposited by thermal vacuum evaporation on different substrates. The devices are annealed under low vacuum at 500 ºC. The Ge doped nanocrystals structure is investigated. The direct transition and band gap values have been estimated using diffuse reflectance spectroscopy and Photoluminescence (PL) measurements. PL indicted that the junctions have emissions from visible to NIR regions that make them promise in white light laser sources as well as waveguiding applications. Charge carrier lifetime and EL measurements show high lifetime and very sharp emission, respectively indicating that the prepared structure is a candidate for white laser diode applications.

Impact of strain engineering and Sn content on GeSn heterostructured nanomaterials for nanoelectronics and photonic devices

“…42b. 16 1.6. Controlling the spectral responsivity, cut-off wavelength, and dark current for GeSn photodetectors (PDs) Sn incorporation in Ge networks increases the absorption coefficient of the GeSn compound.…”

“…18 In our previous work, we developed a method for tuning the bandgap of GeSn-based compounds over a wide range from UV to NIR. 16 It depends on the incorporation of O atoms during the annealing of GeSn compounds under low vacuum conditions, forming GeO x . GeSn-based heterostructures exhibited lasing performance via patterned microdisks as lasing cavities of GeSn with specific dimensions that have threshold power density.…”

“…Sn content can also tune the bandgap value of Ge. [15][16][17] Heterostructures were employed for this target. Multiquantum wells (MQWs) were used for conning the carrier transitions and controlling the bandgap value via the thickness adjustment of MQWs.…”