Presentations

    Black silicon: changing structure and properties with light, at Physics Colloquium, Haverford College (Haverford, PA), Monday, March 1, 2004:
    Shining intense, ultrashort laser pulses on the surface of a crystalline silicon wafer changes its structure and properties dramatically: the formerly smooth, highly reflective surface becomes covered with a forest of sharp microspikes. This microstructured surface is highly absorbing even at wavelengths to which the original wafer is transparent. This talk will describe the properties of this microstructured surface and discuss why the microspikes form and what is responsible for the change in optical properties.
    Femtosecond laser-assisted microstructuring of silicon surfaces for novel detector, sensing, and display technologies, at Physics Colloquium, University of Massachusetts Lowell (Lowell, MA), Wednesday, March 10, 2004:
    Irridiating silicon surfaces with trains of ultrashort laser pulses in the presence of a sulfur containing gas drastically changes the structure and properties of silicon. The normally smooth and highly reflective surface develops a forest of sharp microscopic spikes. The microstructured surface is highly absorbing even at wavelengths beyond the bandgap of silicon and has many interesting novel applications.
    Extending silicon's reach: nonequlibrium doping using ultrafast lasers, at Physics Colloquium, University of Massachusetts, Lowell (Lowell, MA), Wednesday, October 22, 2008:
    Silicon is the world's widely used semiconductor. As the building block of a photovoltaic cell, silicon offers the best combination of stability, efficiency, and manufacturability. However, as an indirect absorber of light, thick layers of highly-pure, expensive material are required for efficient light absorption and charge collection. Furthermore, silicon does not absorb in the infrared, a spectral region that contains about a quarter of the sun's radiation. In this talk, I will discuss non-equilibrium laser-doping techniques we have been developing in the Mazur group that attempt to... Read more about Extending silicon's reach: nonequlibrium doping using ultrafast lasers
    Optical hyperdoping: Extending silicon's reach, at Jones Seminar, Thayer School of Engineering, Dartmouth University (Hanover, NH), Friday, February 13, 2009:
    Silicon is the world's most widely used semiconductor. As the building block of a photovoltaic cell, silicon offers a combination of stability, efficiency, and manufacturability currently unmatched by any other material. However, as an indirect absorber of light, thick layers of highly-pure, expensive material are required for efficient light absorption and charge collection. Furthermore, silicon does not absorb in the infrared, a spectral region that contains about a quarter of the sun's radiation. In this talk, I will discuss optical hyperdoping, a non-equilibrium laser-doping technique we... Read more about Optical hyperdoping: Extending silicon's reach
    Optical Hyperdoping: Silicon sees the infrared light, at Applied Physics Colloquium, Harvard University (Cambridge, MA), Friday, October 9, 2009:
    Shining intense, ultrashort laser pulses on the surface of a crystalline silicon wafer drastically changes the optical, material and electronic properties of the wafer. The resulting textured surface is highly absorbing and looks black to the eye. The properties of this 'black silicon' make it useful for a wide range of commercial devices. In particular, we have been able to fabricate highly-sensitive PIN photodetectors using this material. The sensitivity extends to wavelengths of 1600 nm making them particularly useful for applications in communications and remote sensing.
    Black silicon, at University of Queensland (Brisbane, Australia), Friday, January 15, 2010:
    Shining intense, ultrashort laser pulses on the surface of a crystalline silicon wafer drastically changes the optical, material and electronic properties of the wafer. The resulting textured surface is highly absorbing and looks black to the eye. The properties of this 'black silicon' make it useful for a wide range of commercial devices. In particular, we have been able to fabricate highly-sensitive PIN photodetectors using this material. The sensitivity extends to wavelengths of 1600 nm making them particularly useful for applications in communications and remote sensing.
    Black silicon, at Physics Colloquium, University of Pretoria (Pretoria, South Africa), Thursday, May 31, 2012:
    Shining intense, ultrashort laser pulses on the surface of a crystalline silicon wafer drastically changes the optical, material and electronic properties of the wafer. The resulting textured surface is highly absorbing and looks black to the eye. The properties of this 'black silicon' make it useful for a wide range of commercial devices. In particular, we have been able to fabricate highly-sensitive PIN photodetectors using this material. The sensitivity extends to wavelengths of 1600 nm making them particularly useful for applications in communications and remote sensing.
    Black silicon, at Physics Colloquium, Auburn University (Auburn, AL), Friday, September 19, 2014:
    Shining intense, ultrashort laser pulses on the surface of a crystalline silicon wafer drastically changes the optical, material and electronic properties of the wafer. The resulting textured surface is highly absorbing and looks black to the eye. The properties of this 'black silicon' make it useful for a wide range of commercial devices. In particular, we have been able to fabricate highly-sensitive PIN photodetectors using this material. The sensitivity extends to wavelengths of 1600 nm making them particularly useful for applications in communications and remote sensing.