10-09 :: September 2010
Illuminex Anodic Aluminum Oxide Nanowire Array Production Process to Fabricate SiNW Array Photovoltaic Materials
lluminex is applying recent advancements in its patented anodic aluminum oxide nanowire array
production process to fabricate crystalline silicon nanowire (SiNW) array photovoltaic materials for commercial solar devices. Their bottom-up approach uses molecular self-assembly to manufacture alu- minum catalyzed SiNW. Their process is now demonstrating photovoltaic conversion efficiencies that, when scaled macroscopically, are comparable to crystalline silicon wafer solar cells, except they use 1/100th the amount of silicon per meter of active solar cell area, thereby yielding very significant cost advantages. The technology holds strong potential to reduce the cost of solar electricity from the current value of $0.20-0.40/kWh to under $0.10/kWh, making solar competitive with other forms of electri- cal energy generation.
The potential for Illuminex to introduce disruptive functional nanomaterials to the solar cell market lies in its unique, low-cost methods to produce SiNW arrays using aluminum in a multi-functional capacity (structure, template, catalyst, dopant source, elec- trode isolator, and anode). Illuminex nanostructured materials can be produced at growth rates up to 10 microns/minute with minimal waste materials or process by-products. This is accomplished using a standard chemical vapor deposition (CVD) reactor
and employing the Vapor-Liquid-Solid (VLS) growth method with Illuminex substrate technology in a manner that is readily scalable for mass production.
Illuminex, in collaboration with the Pennsylvania State University, recently applied its VLS and anodic aluminum processes to fabricate these breakthrough SiNW-array-based photovoltaic devices. In June, the research group demonstrated the growth of macro- scopic SiNWs on low-cost substrates and the fabri- cation of a VLS SiNW photovoltaic device (2.5 x 2.5 mm) with an efficiency of 2.4 and single aluminum catalyzed nanowire p-i-n photovoltaic junctions with a preliminary efficiency of 5.3%.
According to Illuminex CEO Joe Habib, „This is com- parable to the highest single nanowire junction effici- ency reported to date, 3.3% (Leiber/Harvard. Nature 2007). Our next step is to make an array over 1 cm² using aluminum on glass resulting in >5% device effi- ciency. Then we move on to get that 20% efficiency obtained using crystalline silicon wafers at a fraction of the cost using 1/100th the material.“
To accelerate its photovoltaic materials and develop- ment efforts, and with financial assistance from the State of Pennsylvania, the company just completed construction of a new silicon processing laboratory