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Optical Science and
Technology Center

OSTC Seminar "Silicon nanowire based solar cells and biosensors"

Dr. Marcie Black
104 Iowa Advanced Technology Center (IATL)

"Silicon nanowire based solar cells and biosensors"

Thursday, November 12, 2015
1:30 p.m.
104 Iowa Advanced Technology Laboratories (IATL)

Dr. Marcie Black
CEO and co-founder of Advanced Silicon Group


Silicon nanowires have many unusual material properties that make them uniquely suited for many applications.  For example, the high surface area to volume ratio of nanowires makes them ideal for medical sensors.  We propose a sensor that has a million nanowires compared to other nanowire sensors that have a handful of nanowires.  This sensor can detect prostate cancer from a drop of blood.  Nanowire arrays can also improve the optical properties of silicon solar cells.  We will present results that show that the commonly-held concerns about the effects of nanostructuring on device performance have been overcome.  Here we present experimental results of our design and processing innovations applied to silicon-nanowire solar cells that confirm the excellent anti-reflection and absorption benefits, demonstrate high minority carrier lifetime and efficiencies >18.5%.  Nanowires enhance the efficiency of crystalline silicon solar cells by reducing reflection over a broad range of incident wavelengths and angles: measured reflection is less than 1% for a weighted average over the solar spectrum.   Furthermore, the nanowires increase the optical path length within the device, allowing the absorption of the silicon to approach the Lambertian limit for light trapping. This increased absorption improves efficiency for standard thickness cells (mainly in the infrared), as well as significantly increasing the amount of light absorbed in thin crystalline silicon cells. Our nanowire fabrication process works on all crystallographic orientations and overall is especially well-suited for multicrystalline, thin crystalline silicon cells, and n-type mono cells.  Our nanowire solar cells are fabricated with a low-cost process and we will discuss the benefits of integrating them into existing solar cell production lines and how they can potentially increase the efficiency by 1% and reduce costs.


Marcie Black is CEO and co-founder of Advanced Silicon Group.  ASG is commercializing silicon nanowires for use in medical devices, solar cells, batteries, thermoelectrics, and MEMs applications.  Prior to founding ASG, Marcie was the President and co-founder of Bandgap Engineering.  Bandgap focused on replacing coal plants with solar fields by lowering the cost of solar electricity.  Dr. Black has dedicated her career to making renewable energy more cost effective.  She has more than twenty years’ experience in the solar energy, semiconductor, and the opto-electronic industries. Before joining Bandgap, Marcie was a technical staff member at Los Alamos National Laboratory and worked on a variety of nanotechnology and optical systems.  She began at Los Alamos National Labs as a prestigious Director’s Funded Post Doc, developing organic and nano solar cells. Her Ph.D. is from MIT in Electrical Engineering, under the supervision of Institute Professor, Mildred Dresselhaus.  Prior to her Ph.D. work, Marcie was a device engineer at Motorola where she was on a small team responsible for combining non-volatile memory and logic onto the same chip.  She improved the manufacturing yields by working with the process engineer to improve silicide formation.  In 2009, she was awarded an R&D 100 award for her contributions to work at LANL.  Marcie also was honored as one of the ten “Women-to-Watch in 2010” by Mass High Tech.

Dr. Black has expertise in building strong teams, managing development projects, patents, IP strategy, encouraging a healthy company culture, cost modeling, and running a startup.  In addition, Marcie has a strong technical background in the areas of electronic materials, optics, semiconductors, solar cells/photovoltiacs, batteries, renewable energy, nanotechnology, device design, and opto-electronics.


Download flyer here


Individuals with disabilities are encouraged to attend all University of Iowa sponsored events. If you are a person with a disability who requires an accommodation in order to attend this program, please contact the Optical Science & Technology Center in advance at 353-0974 or email