Emerging Materials and Nanotechnology

Quantum dots (QDs) represent semiconductor 3D nano crystals with electronic and optical characteristics controlled by their morphology, size and coating. Typically created semiconductor group II–VI materials such as Titanium oxide TiO₃, Cadmium selenide (CdSe), Cadmium telluride (CdTe), Cadmium Sulphide CdS … etc. QDs have numerous applications such as Solar Cells , medicine and, and fabrication of LEDs. The fluorescence of the QD optical can be altered by the strong quantum confinement ranges from few to 10 nm nano crystals which allow for tuning of the fluorescence emission bands. Nevertheless, the QD efficiency affected by many parameters such as; type and quantity of impurities in QDs which will fluctuate the electronic traps, especially the dangling bonds, in the interface between the core and the coating of the QDs.

 

In this work, the fundamental wavelength of Nd:YAG laser at repetition rate 10 Hz to analysis the impurities in the QDs using laser induced plasma spectroscopy LIPS. The plasma parameters were controlled to adapt the local thermodynamic equilibrium conditions (LTE) for optically thin plasma. The observed results gave a qualitative LIPS analysis investigation for the available impurities in the semiconductor QDs. The obtained results gave a precise detail of the semiconductor sample compositions including the types of these impurities. Consequently, these results can be applied in prospective work in which to control the impurities contents in such QDs samples which could be used to control the electrical, optical and physical properties of the semiconductor QDs in future