Photoemission investigation of compound semiconductor monodisperse clusters

Journal Article · Wed May 01 00:00:00 EDT 1991 · Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (USA)

DOI:https://doi.org/10.1116/1.577328· OSTI ID:5686167

Tobin, J G ^[1]; Colvin, V L; Alivisatos, A P ^[2]

---

1. Lawrence Livermore National Laboratory, Livermore, California 94551 (USA)
2. University of California, Berkeley, California 94720 (USA)

We have used synchrotron radiation photoemission to probe the valence and core level electronic structure of compound-semiconductor monodisperse clusters (nanocrystals). These clusters exhibited a 10% or less variation relative to the mean diameter and were attached to the metal substrates via alkane chains. Direct evidence of gap broadening due to size variation in CdS clusters was observed. The novel utilization of alkane chain attachment is the key to eliminating the otherwise debilitating problem of sample charging, as occurs with powders. The quality of sample preparation was confirmed by other methods such as transmission electron microscopy, Raman scattering, and x-ray diffraction. This work provides a direct link between photoemission studies of expitaxial ultrathin films of compound semiconductors, the photon-spectroscopy measurements of cluster powders and the existing theories of quantum confinement in reduced dimensionality structures.

• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5686167
• Journal Information: Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (USA), Journal Name: Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (USA) Vol. 9:3; ISSN JVTAD; ISSN 0734-2101
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
BREMSSTRAHLUNG
CADMIUM COMPOUNDS
CADMIUM SULFIDES
CHALCOGENIDES
COHERENT SCATTERING
DIFFRACTION
ELECTROMAGNETIC RADIATION
ELECTRON MICROSCOPY
ELECTRON SPECTROSCOPY
ELECTRONIC STRUCTURE
INORGANIC PHOSPHORS
MATERIALS
MICROSCOPY
PHOSPHORS
PHOTOELECTRON SPECTROSCOPY
RADIATIONS
RAMAN SPECTRA
SCATTERING
SEMICONDUCTOR MATERIALS
SOLID CLUSTERS
SPECTRA
SPECTROSCOPY
SULFIDES
SULFUR COMPOUNDS
SYNCHROTRON RADIATION
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION