PV Gap

Eduardo Said:

what are the material properties of micro-crystalline silicon?

We Answered:

Microcrystalline silicon–germanium (?c-Si1?xGex:H) alloy films have been grown by 100-MHz glow-discharge of a SiH4/GeH4/H2 gas mixture. Alloys over a full range of compositions were prepared to gain a comprehensive understanding of their growth and material properties. With increasing GeH4 concentration in the gas-phase, we observed a preferential Ge incorporation behavior in the solid. Growth rate studies revealed that the Ge incorporation efficiency from source gas to solid is about five times greater than for Si at growth temperature of 200 °C, which accounts for the variation of alloy composition. With increasing Ge incorporation in the solid, on the other hand, we find a monotonic decrease in photoconductivity, followed by an electrical transition from weak n-type to strong p-type conduction at x > 0.7. At x ? 0.4, however, we obtained relatively high photoconductivity gains by a factor of 20 and strong infrared response in the solar cell structure. The Ge incorporation behavior and its effect on charge carrier transport are discussed.

Maxine Said:

what are the material properties of Amorphous silicon?

We Answered:

External links and references
General
"Solar Resources (http://www.sunpowercorp.com/html/Resourc… SunPower Corporation, 2004.
"History: Photovoltaics Timeline (http://inventors.about.com/library/inven… About, Inc., 2005.
"Bell Labs Celebrates 50th Anniversary of the Solar Cell - Timeline (http://www.bell-labs.com/news/2004/april… Lucent Technologies, 2004.
Lenardic, Denis, "History of photovoltaics (http://www.pvresources.com/en/history.ph… PVResources.com, 2005.
Perlin, John, "Making Electricity Directly from Sunlight (http://www.californiasolarcenter.org/sol… Rahus Institute, 2002.
Massey, David, "Bell Labs - The Solar Battery (Photovoltaics) (http://www.bellsystemmemorial.com/bellla… 2005.
Perreault, Bruce A., "Nikola Tesla's Radiant Energy system (http://www.nuenergy.org/alt/tesla_energy…
Trinkaus, George, "The Lost Inventions of Nikola Tesla". Free Energy Receiver (http://www.t0.or.at/tesla/tesfreee.htm), Chapter 9.
"Solar Energy Timeline (http://www.newton.mec.edu/Brown/TE/HOT/T… Charles E. Brown Middle School.
"Centre for Photovolatic Engineering Timeline (http://www.pv.unsw.edu.au/online-course/… University of New South Wales
http://www.pvpower.com/pvhistory.html
http://www.eetimes.com/news/semi/showArt…
http://www.mysolar.com/pv/techwattpeak.a…
"Net Energy Analysis For Sustainable Energy Production From Silicon Based Solar Cells (</ref><ref>"Whathttp://jupiter.clarion.edu/~jpearce/Pape… is the Energy Payback for PV? (http://www.nrel.gov/docs/fy05osti/37322.…
{{{author}}}, "Can Solar Cells Ever Recapture the Energy Invested in their Manufacture?", Solar Progress. 18, 1997. pages 16-17
http://www.spectrolab.com/DataSheets/Ter…
http://www.spectrolab.com/
http://minerals.usgs.gov/minerals/pubs/c…
Tuttle et el., DESIGN CONSIDERATIONS AND IMPLEMENTATION OF VERY-LARGE SCALE MANUFACTURING OF CIGS SOLAR CELLS AND RELATED PRODUCTS, 20th European Photovoltaic Solar Energy Conference and Exhibition, Spain, 2005
http://www.nrel.gov/news/press/release.c…
http://www.nrel.gov/ncpv/new_in_cpv.html
World-leading mega scale station for Victoria, http://www.solarsystems.com.au/documents… Solar Systems Pty Ltd., accessed October 25 2006
http://www.spectrolab.com/
School of Photovoltaic and Renewable Energy Engineering (Research lab of Prof. Martin Green et al.) (http://www.pv.unsw.edu.au/)
Animation of how a solar cell works (http://www.energex.com.au/switched_on/ac…
Carbon Nanotube Solar Cells (http://www.azonano.com/news.asp?newsID=5… (28 February 2005)
Flexible Silicon Solar Cells (http://www.newscientist.com/news/news.js… (15 February 2003)
Historical: Photovoltaic Solar Energy Conversion: An Update (http://www.atse.org.au/index.php?section… (M. Green, 1998)
Howstuffworks.com: How Solar Cells Work (http://science.howstuffworks.com/solar-c…
Organic Photovoltaics and Materials - Overview (http://www.oe-chemicals.com/dictionaryM-…
Organic Solar Cells for the Near-Infrared Spectrum (http://www.greenpowermagazine.com/images…
Photovoltaic Residential Benefits (http://www.m8electric.com/solar_repair_a…
Photovoltaic Solar Panel Overview (http://www.solarpanelinfo.com/)
Photovoltaic Thin Films for the Full Solar Spectrum (http://www.lbl.gov/msd/PIs/Walukiewicz/0… (W. Walukiewicz 2002)
Pliable solar cells are on a roll (http://www.newscientist.com/article.ns?i…
Superefficient, Cost-Effective Solar Cell Breaks Conversion Records (http://www.sciam.com/article.cfm?chanID=… - 40.7 percent efficiency achieved (Scientific American, December 2006)
Photovoltaics (http://www.energyplanet.info/Photovoltai… - A visual directory of solar energy websites. (EnergyPlanet.info)
Yield data

Bernard Said:

what are the material properties of copper indium selenide/sulfide?

We Answered:

The chalcogenide semiconductors (e.g., CuGaSe2, AgInTe2, etc.) have lower melting points relative to their band gaps than the binary compound semiconductors (e.g., CdTe) or, even more so, the elementary semiconductors (e.g., Si.)
This can be a great convenience. It's only recently that the technology has developed to make these compounds with precise stoichiometry and thus make possible precise doping.
I published a paper way back in 1965 on two of these compounds in J. Phys. Chem. Solids. It was a piece of work before its time and was not appreciated.