Journal ArticleDOI
Highly Efficient Charge Separation and Collection across in Situ Doped Axial VLS-Grown Si Nanowire p–n Junctions
Aditya D. Mohite,Daniel E. Perea,Sanjeev Singh,Shadi A. Dayeh,Ian Campbell,S. T. Picraux,Han Htoon +6 more
TLDR
The degree of surface passivation achieved in this paper is comparable to or better than that achieved for nanowires in prior studies at significantly larger diameters, and it is suggested that the dramatically improved surface recombination velocities may result from the reduced sidewall reactions and deposition in the authors' cold wall CVD reactor.Abstract:
VLS-grown semiconductor nanowires have emerged as a viable prospect for future solar-based energy applications. In this paper, we report highly efficient charge separation and collection across in situ doped Si p–n junction nanowires with a diameter <100 nm grown in a cold wall CVD reactor. Our photoexcitation measurements indicate an internal quantum efficiency of ∼50%, whereas scanning photocurrent microscopy measurements reveal effective minority carrier diffusion lengths of ∼1.0 μm for electrons and 0.66 μm for holes for as-grown Si nanowires (dNW ≈ 65–80 nm), which are an order of magnitude larger than those previously reported for nanowires of similar diameter. Further analysis reveals that the strong suppression of surface recombination is mainly responsible for these relatively long diffusion lengths, with surface recombination velocities (S) calculated to be 2 orders of magnitude lower than found previously for as-grown nanowires, all of which used hot wall reactors. The degree of surface passiva...read more
Citations
More filters
Journal ArticleDOI
Silicon nanostructures for photonics and photovoltaics
TL;DR: Focusing on two application areas, namely communications and photovoltaics, the state of the art in each field is assessed and the challenges that need to be overcome are highlighted to make silicon a truly high-performing photonic material.
Journal ArticleDOI
Nanowire Electronics: From Nanoscale to Macroscale
TL;DR: A comprehensive review of the continuing efforts in exploring semiconductor nanowires for the assembly of functional nanoscale electronics and macroelectronics, including a unique design of solution-processable nanowire thin-film transistors for high-performance large-area flexible electronics.
Journal ArticleDOI
Design Principles for Photovoltaic Devices Based on Si Nanowires with Axial or Radial p–n Junctions
Joseph D. Christesen,Xing Zhang,Christopher W. Pinion,Thomas A. Celano,Cory J. Flynn,James F. Cahoon +5 more
TL;DR: Finite-element modeling of axial and radial Si NW p-n junctions with total diameters of ~240 nm and donor/acceptor doping levels ranging from 10(16) to 10(20) cm(-3) is presented, and it is expected that insights from finite element modeling will serve as a powerful method to guide the design of advanced nanoscale structures.
Journal ArticleDOI
Direct imaging of free carrier and trap carrier motion in silicon nanowires by spatially-separated femtosecond pump-probe microscopy.
Michelle M. Gabriel,J. Kirschbrown,Joseph D. Christesen,Christopher W. Pinion,David F. Zigler,Erik M. Grumstrup,Brian P. Mehl,Emma E. M. Cating,James F. Cahoon,John M. Papanikolas +9 more
TL;DR: A pump-probe microscope capable of exciting a single semiconductor nanostructure in one location and probing it in another with both high spatial and temporal resolution shows clear evidence of rapid diffusional spreading and recombination of the free carriers.
Journal ArticleDOI
Doubling absorption in nanowire solar cells with dielectric shell optical antennas.
Sun Kyung Kim,Xing Zhang,David Hill,Kyung Deok Song,Jin Sung Park,Hong Gyu Park,James F. Cahoon +6 more
TL;DR: This work demonstrates a simple, low-cost, and scalable route to dramatically enhance the optical antenna effect in NW photovoltaic devices by coating the wires with conformal dielectric shells, providing a simple route to approximately double the efficiency of NW-based solar cells.
References
More filters
Journal ArticleDOI
Vapor‐liquid‐solid mechanism of single crystal growth
R. S. Wagner,W. C. Ellis +1 more
Journal ArticleDOI
Coaxial silicon nanowires as solar cells and nanoelectronic power sources
Bozhi Tian,Xiaolin Zheng,Thomas J. Kempa,Ying Fang,Nanfang Yu,Guihua Yu,Jinlin Huang,Charles M. Lieber +7 more
TL;DR: These coaxial silicon nanowire photovoltaic elements provide a new nanoscale test bed for studies of photoinduced energy/charge transport and artificial photosynthesis, and might find general usage as elements for powering ultralow-power electronics and diverse nanosystems.
Journal ArticleDOI
Growth of nanowire superlattice structures for nanoscale photonics and electronics.
Mark S. Gudiksen,Lincoln J. Lauhon,Jianfang Wang,David C. Smith,Charles M. Lieber,Charles M. Lieber +5 more
TL;DR: Single-nanowire photoluminescent, electrical transport and electroluminescence measurements show the unique photonic and electronic properties of these nanowire superlattices, and suggest potential applications ranging from nano-barcodes to polarized nanoscale LEDs.