The quantum dots manufactured in Bochum are generated in the semiconductor material indium arsenide
. The researchers grow the material on a gallium arsenide substrate.
Quantum Dot Comprehensive Study by Type (QLED, QDEF), Application (Biological Imaging, Optoelectronics, Quantum Optics, Security & Surveillance, Renewable Energy), Technology (Colloidal synthesis, Fabrication, Viral assembly, Electrochemical assembly, Bulk manufacturing, Cadmium-free QD technology), Material (Cadmium Selenide, Cadmium Sulphide, Cadmium Telluride, Indium Arsenide
, Silicon), Component (LED, Glass Tube, Film), End user Devices (QD Medical Devices, QD LCD, LED Display Devices, QD Laser Devices, QD Pho
Quantum dots have been made from a variety of elements and their compounds, including cadmium selenide (CdSe), mercury telluride (HgTe), lead selenide (PbSe), lead sulfide (PbS), indium arsenide
(InAs), or simply from silicon (Si) or carbon (C), just to name a few.
Moreover, Fujitsu Laboratories has strengthened the resistance against thermal noise of the electron collection layer that connects to the absorption layer, which consists of alternate layers of semiconducting thin films of indium arsenide
(InAs) and gallium antimonide (GaSb).
With colloidal synthesis, one of several industrial production techniques, quantum dots are being produced using standard chemical processes--precursor chemicals are heated until they become monomers of alloys such as cadmium selenide, cadmium sulfide, indium arsenide
, and indium phosphide, with which to grow nanocrystals.
QD technology based materials cover cadmium selenide, cadmium sulphide, cadmium telluride, indium arsenide
, graphene, and silicon.
One tool in their arsenal is molecular beam epitaxy, in which a thin stream of precursor molecules containing semiconducting materials--often indium arsenide
or gallium arsenide--is directed at a metal catalyst which controls crystal growth.
Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC), Berkeley, have successfully integrated ultra-thin layers of the semiconductor indium arsenide
onto a silicon substrate to create a nanoscale transistor with excellent electronic properties.
Through a series of calculations, the researchers conclude that mixtures of air and the alloy gallium indium arsenide
phosphide would create such a material.
Instead of using a germanium wafer as the bottom junction of the device, the new design uses compositions of gallium indium phosphide and gallium indium arsenide
to split the solar spectrum into three equal parts that are absorbed by each of the cell's three junctions for higher potential efficiencies.
Gallium antimonide, germanium, or certain III-V materials like gallium indium arsenide
are promising materials for these devices.