| Abstract [eng] |
Until now, it has generally been assumed that high-quality GaAsBi can only be grown under nearly stoichiometric Ga and As flux conditions. In this work, the investigated growth window was expanded, and four distinct growth regimes were identified. The stoichiometric regime was found to be suitable for growing thick GaAsBi layers. Structures grown under these conditions showed good reproducibility and strong photoluminescence emission. Under higher arsenic flux, Bi incorporation into the lattice was suppressed, making this regime unsuitable for GaAsBi technology. Structures grown under slightly As-deficient conditions exhibited weak emission intensity and significantly degraded surface quality. An unexpected result was obtained when the arsenic flux was reduced further. Samples grown using As/Ga flux ratios from 0.22 to 0.45 exhibited strong emission, a narrow photoluminescence emission band, and reduced temperature-induced intensity quenching. This important result showed that these previously unexplored growth conditions may be favorable for growing thin quantum structures. Therefore, this technology was transferred to the fabrication of electrically pumped GaAsBi emitters. Different designs of light emitting diodes and laser diodes are presented in this work. Light emitting diodes were used as an initial demonstration of the technological applicability of the developed approach. The possibility of growing components compatible with integration on a SiC platform was also investigated. Laser diodes based on GaAsBi quantum wells demonstrated lasing in the 1014-1107 nm wavelength range under pulsed operation. Finally, by combining the optimized results achieved throughout the work, from the optimization of thick-layer growth technology to the improvement of emitter design, a peak output power of 130 mW was achieved for a GaAsBi laser diode, with a threshold current of 250 mA. |
