Optical properties of InAs/InP quantum dot stack grown by metalorganic chemical vapor deposition

Abstract

The 5-layer InAs quantum dot (QD) stack was grown on an (001) InP substrate by low pressuremetalorganic chemical vapor deposition. 40 nm InP spacer layers were inserted between the InAs QDs. The integrated intensity of the photoluminescence peak at 300 K was over 12% of that at 10 K. Farinfrared absorption peaks were observed at 819 cm −1 (101.64 meV) and 518 cm −1 (64.08 meV) from this structure at room temperature by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Raman analysis showed that the peak at 819 cm −1 was attributed to a plasmon related peak in the n-type InP substrate. The absorption peak at 518 cm −1 was regarded as a peak related with intersubband transition in the InAs QDs, suggesting that room temperature operating quantum dot devices may be fabricated.