111 research outputs found
Double quantum dots as a high sensitive submillimeter-wave detector
A single electron transistor (SET) consisting of parallel double quantum dots
fabricated in a GaAs/AlGaAs heterostructure crystal is
demonstrated to serve as an extremely high sensitive detector of submillimeter
waves (SMMW). One of the double dots is ionized by SMMW via Kohn-mode plasma
excitation, which affects the SET conductance through the other quantum dot
yielding the photoresponse. Noise equivalent power of the detector for
wavelengths about 0.6 mm is estimated to reach the order of
W/ at 70 mK.Comment: 3 pages, 4 figures, REVTeX, submitted to Appl.Phys.Let
Elastic Mid-Infrared Light Scattering: a Basis for Microscopy of Large-Scale Electrically Active Defects in Semiconducting Materials
A method of the mid-IR-laser microscopy has been proposed for the
investigation of the large-scale electrically and recombination active defects
in semiconductors and non-destructive inspection of semiconductor materials and
structures in the industries of microelectronics and photovoltaics. The basis
for this development was laid with a wide cycle of the investigations on the
low-angle mid-IR-light scattering in semiconductors. The essence of the
technical idea was to apply the dark-field method for spatial filtering of the
scattered light in the scanning mid-IR-laser microscope. This approach enabled
the visualization of large-scale electrically active defects which are the
regions enriched with ionized electrically active centers. The photoexcitation
of excess carriers within a small volume located in the probe mid-IR-laser beam
enabled the visualization of the large-scale recombination-active defects like
those revealed in the optical or electron beam induced current methods. Both
these methods of the scanning mid-IR-laser microscopy are now introduced in
detail in the present paper as well as a summary of techniques used in the
standard method of the lowangle mid-IR-light scattering itself. Besides the
techniques for direct observations, methods for analyses of the defect
composition associated with the mid-IR-laser microscopy are also discussed in
the paper.Comment: 44 pages, 13 figures. A good oldi
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