Spire awarded patent for synthesis of quantum-dot nanostructures

February 13, 2008, Bedford, MA--Spire Corporation, a global solar company providing turnkey solar factories and capital equipment to manufacture photovoltaic modules, cells, and wafers worldwide, has been awarded US Patent #7,306,963, "Precision Synthesis of Quantum Dot Nanostructures for Fluorescent and Optoelectronic Devices."

This patent describes a method for designing and synthesizing quantum dot nanoparticles with improved uniformity and size. These quantum dots have the potential to create new high efficiency, low-cost solar cells and other optoelectronic devices such as lasers, light emitting diodes (LEDs), and photodetectors. The extremely small size of these structures also makes them useful for medical assays, diagnostic systems, and therapeutic compounds.

"Quantum dot technology represents an exciting field of research in solar energy today," said Roger G. Little, Chairman and CEO of Spire Corporation. "Quantum dots have the potential to improve the efficiency of solar cells beyond levels currently available, and quantum dots also have important applications in the fields of medical research and diagnostics. The challenge has always been how to manufacture these small structures with the consistency needed to take advantage of their unique properties. Our scientists have conceived of a large-scale method that may allow the promise of this technology to be realized."

Quantum dots are nanometer-sized semiconductor structures which, when exposed to light at predetermined wavelengths, can generate free electrons and create an electrical current. The confinement of electrons in these minute three-dimensional structures gives scientists the ability to use quantum dots to precisely control the optical properties of various devices, such as a solar cell or a biomarker for detecting cancer.

"The technique we conceived for fabricating the quantum dots involves using compound semiconductor technology developed at Spire Semiconductor, Spire Corporation's solar cell manufacturing operation," said Kurt J. Linden, Ph.D., Senior Scientist at Spire Corporation. "It involves the synthesis of free-standing nanoparticles by using a specially designed release layer that separates uniformly sized nanoparticles from gallium arsenide (GaAs) thin films that are grown in our existing GaAs wafer fabrication systems. Such techniques are expected to achieve large-scale volumes of active nanostructures with a highly consistent size. This consistency of size can provide a number of important scientific and commercial benefits."