Gary Hodes   Gary Hodes

Associate Professor
Department of Materials and Interfaces
Weizmann Institute of Science
Rehovot 76100, Israel
Tel. 972-8-9342076
E-mail:   gary.hodes@weizmann.ac.il

Semiconductor Quantum Dot Films

Our research centres around thin films of nanocrystalline semiconductor deposited by solution methods (chemical bath deposition and electrodeposition). We are interested in several aspects of these nanocrystalline films, as well as in various aspects of the deposition processes themselves.

Chemically-deposited CdSe films on glass
Chemical bath deposited CdSe films on glass.
The numbers above the films give the crystal size in nm.

Size quantization
The electronic structure and therefore optical and electronic properties of the semiconductors vary as a function of crystal size (in this regime, the semiconductor nanocrystals are known as quantum dots). Besides learning to control quantum dot size, we also study interactions between neighbouring quantum dots (in aggregated films) which, for small enough quantum dots (< 4 nm) act to lower the degree of size quantization.

Surface modification
Because of the very high surface area of many of these films (typically several tens of percent of all atoms are surface atoms), they are particularly sensitive to adsorption of various species. We follow changes in properties (optical, electrical) with adsorption of various inorganic species.

Charge transport and solar cells
Charge transport in porous, nanocrystalline films is being investigated, with particular emphasis on the mechanisms of charge transport (usually space charge layer-free) and the effects of surface states on charge transport. We continue a long-term interest in various types of thin film solar cells.

Publications since 2001:

Papers

Books (authored)

Books (edited)

Books Chapters