Optical and electrical properties of films of CdSe quantum dots epitaxially electrodeposited onto gold have been measured by modulated optical spectroscopy, liquid junction photoresponse spectroscopy and local current-voltage spectroscopy using a metallized scanning probe tip. The blue shift in the bandgap resulting from quantum confinement in the quantum dots has been measured by all these techniques. Large differences in the charge collection efficiency between the first and subsequent layers of dots have been measured and explained by the positive role of grain boundaries in enhancing collection efficiency in these films. Single electron transfer through the dots has been observed and explained by the large charging energies of the very small (4–5nm) dots.
|Title of host publication||Fine Particles Science and Technology|
|Number of pages||12|
|State||Published - 1 Jan 1996|