1. CdS & CdSe Nanocrystals Grown in Glass  Nazanin Hosseinkhah  1382/3/12

2. In Atomic Scale:  Electronic Properties  Optical Properties  Magnetic Properties  Thermodynamic Properties

3. Three Stages of Nanocrystals:  Decomposition Nucleation  Growth at The Expense of Solved Matter  Recondensation Growth

4. Techniques to Grow Semiconductor NC:  Co-Sputtering Technique  Ion Implantation  Wet Chemistry  The Melting

5. Radio-Frequency Magnetron Sputtering  Advantages: 1 Inexpensive 2 Suitable Way for Growing Nanoparticles  Mean Diameter of NC 4-6 nm  High Resolution Transmission Electron Microscopy (HRTEM)  Low Concentration Homogeneous Distribution  High Concentration Columnar Structure

6. Low Con. 4.9nm High Con. 5.8nm

8. NO Sign of Quantized Energy Level !

9. Ion Implantation Advantages: 1 More Freedom From thermodynamical limitation 2 Extreme Chemical Purity 3 Compatibility With Planar Technology Disadvantage: 1 Damage The Lattice by Implantation Depth Implantation & Annealing Parameters Application Tunable Light Absorbers X-Ray Result Hexagonal,Wurtzite Structure

10. Ion Dose Control The Stoichiometry Energy Depth 10nm Particles

11. Different Ion Doses:  T = Constant.  D1 = 2.5 * 10^16  D2 = 5 * 10^16  D3 = 1 * 10^17  D3>D2>D1

12. Derivation of Absorbance:

13. Theoretical Background Solid-Phase (Glass) High Activation Energy for Nucleation & Diffusion Formation Limited by Homogeneous Nucleation (Thermodynamic Concentration Fluctuation of The Reactants) Delta G v Is Bulk Free Energy Per Unit Volume  Is Phase Interaction Energy Per Unit Area

14. Thank You for Your Attention