News Article
In-situ monitoring speeds up InP nanowire production
Researchers have found that in-situ monitoring can provide vital information on the evolution of indium phosphide nanowire lengths and diameters during growth
Nanowires, sometimes called nanorods, are becoming more and more attractive for next generation LED and solar cell applications.
One of the reasons is the fact that epitaxial III-V nanowire arrays combine 1-dimensional electronic states with additional degrees of freedom for strain relaxation and resonant electromagnetic interaction.
The most critical parameters for nanowires’ optical response are their length and diameter. Usually, time consuming and destructive ex-situ methods like scanning electron microscopy (SEM) are used for characterisation before further processing.
But now, LayTec and the Nanometre Structure Consortium at Lund University in Sweden have jointly developed a solution for real-time quantitative monitoring of III-V nanowire growth.
The team of Lars Samuelson used LayTec’s spectroscopic in-situ reflectometer EpiR to monitor nanowire epitaxy in an AIXTRON 200/4 reactor. The image below shows the LayTec software display at the end of the MOCVD run where InP shells were grown on InP core nanowires.
LayTec software display at the end of a nanowire growth run. In the plot, shown on the left, the reflectance is given by the colour. (©nmC@LU)
The data of previous ex-situ analysis by SEM and spectroscopic reflectance were used by Nicklas Anttu of Lund University to develop numerical algorithms for deduction of the average length and diameters of the growing nanowire ensemble. This work is described in more detail in the paper, "Optical Far-Field Method with Subwavelength Accuracy for the Determination of Nanostructure Dimensions in Large-Area Samples," by N. Anttu et al, in Nano Letters, 2013, 13 (6), pp 2662 - 2667. DOI: 10.1021/nl400811q
Together with these algorithms, the in-situ spectroscopic measurements by EpiR provide information on the evolution of nanowire length and diameter during growth.
SEM image of InP nano-wires structured with gold particles by nanoimprint lithography. ©nmC@LU.
EpiR enables effective process optimisation, speeds up development and paves the way to future process transfer for industrial nanowire growth. LayTec believes in-situ metrology will be a must in nanowire applications in the near future.
One of the reasons is the fact that epitaxial III-V nanowire arrays combine 1-dimensional electronic states with additional degrees of freedom for strain relaxation and resonant electromagnetic interaction.
The most critical parameters for nanowires’ optical response are their length and diameter. Usually, time consuming and destructive ex-situ methods like scanning electron microscopy (SEM) are used for characterisation before further processing.
But now, LayTec and the Nanometre Structure Consortium at Lund University in Sweden have jointly developed a solution for real-time quantitative monitoring of III-V nanowire growth.
The team of Lars Samuelson used LayTec’s spectroscopic in-situ reflectometer EpiR to monitor nanowire epitaxy in an AIXTRON 200/4 reactor. The image below shows the LayTec software display at the end of the MOCVD run where InP shells were grown on InP core nanowires.
LayTec software display at the end of a nanowire growth run. In the plot, shown on the left, the reflectance is given by the colour. (©nmC@LU)
The data of previous ex-situ analysis by SEM and spectroscopic reflectance were used by Nicklas Anttu of Lund University to develop numerical algorithms for deduction of the average length and diameters of the growing nanowire ensemble. This work is described in more detail in the paper, "Optical Far-Field Method with Subwavelength Accuracy for the Determination of Nanostructure Dimensions in Large-Area Samples," by N. Anttu et al, in Nano Letters, 2013, 13 (6), pp 2662 - 2667. DOI: 10.1021/nl400811q
Together with these algorithms, the in-situ spectroscopic measurements by EpiR provide information on the evolution of nanowire length and diameter during growth.
SEM image of InP nano-wires structured with gold particles by nanoimprint lithography. ©nmC@LU.
EpiR enables effective process optimisation, speeds up development and paves the way to future process transfer for industrial nanowire growth. LayTec believes in-situ metrology will be a must in nanowire applications in the near future.
