near-field imaging
DESCRIPTION
Trapped Nano-particles. CdSe nanoparticle. EPDT: INTEGRATION OF LIGHT EMITTING NANO-PARTICLES ON SCANNING PROBE FOR NEAR FIELD IMAGING AND NANOPATTERNING OF BIOMATERIALS. Kazunori Hoshino 1 ,3,4 , Lynn Rozanski 2 ,4 , David A. Vanden Bout 2 ,4 and Xiaojing Zhang 1 ,3,4 - PowerPoint PPT PresentationTRANSCRIPT
Near-field imaging• Tip-sample distance was maintained about 5nm while the tip scans the surface
topography
• Transmitted light from the Nano-LED is measured by a photon counter
• Topographic and optical resolution were measured to be approximately 50nm and 500n
Conclusions• We fabricated nano-scale light source on the tip of a MEMS silicon probe
• The probe successfully traced nano-scale topography of the sample.• Transmitted light through sample was recorded as the probe scan the sample
References[1] A.P. Alivisatos J Phys Chem 100, 13226 (1996)
[2] R. A. M. Hikmeta, D. V. Talapin and H. Weller, J. Appl. Phys. 93 3509 (2003)
[3] G.T. Dagani, J.R. Fakhoury, W.G. Shin, J.C. Sisson and X.J. Zhang, proc Micro-TAS 1411(2006)
[4] W.S. Chang, J. Kim, S.H. Cho and K.H. Whang, Jpn. J. Appl. Phys. 45 2083 (2006)
[5] K. Karraia and R. D. Grober, Appl. Phys. Lett. 66, 1842 (1995).
Publications[1] K. Hoshino, L.Rozanski, D. VandenBout and X.J. Zhang, Proc. IEEE MEMS 2007
[2] K. Hoshino, L.Rozanski, D. VandenBout and X.J. Zhang, Journal of Microelectro mechanical systems (accepted)
[3] K. Hoshino, A. Gopal. D. Ostrowski, L.Rozanski, A. Heitsch , R. Patel, B Korgel, D. VandenBout and X.J. Zhang, Proc. IEEE MEMS 2008 (accepted)
Introduction• We have built a nanoscale light emitting diode (LED) on a silicon MEMS
probe for near-field scanning optical microsopy (NSOM)
• The LED was made of semiconductor nano- particles (CdSe/ZnS core-shell nanoparticles [1,2])
• The probe is suitable for nano-scale imaging and patterning of functional biomaterials [3,4].
Light source characteristics• LED fabricated on the probe tip emitted light Clear diode properties were
measured for current-voltage and lignt intensity-voltage relationship
• Several emission wavelengths have been achieved
EPDT: INTEGRATION OF LIGHT EMITTING NANO-PARTICLES ON SCANNING PROBE FOR NEAR FIELD IMAGING AND NANOPATTERNING OF BIOMATERIALS
Kazunori Hoshino1,3,4, Lynn Rozanski2,4, David A. Vanden Bout2,4 and Xiaojing Zhang1,3,4 1Department of Biomedical Engineering, 2Department of Chemistry and Biochemistry
Microelectronics Research Center3 and Center for Nano and Molecular Materials Science and Technology4, The University of Texas at Austin, USA
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1 µm
TrappedNano-
particles
]m/cd[102.2Luminance
]m[100.9nm)150(4(est.) areaEmission
]cd[100.2intensity Luminous
]W[106.3powerEmission
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Optical imaging Topographic imaging
Light intensity I-V characteristics Light intensity and current
Figure 1. Nano-scale light source on a silicon probe
Figure 3. light-source characteristics
Figure 4. Experimental NSOM set up
Figure 5. Obtained topographic and optical images
Optical image
2µm
Violet RedYellowGreenTurqoizBlue
Nano-LEDs with different emission wavelengths
2 mm
Photosensor
Silicon probe
z-control(topography)
Transmission
x-y scan(stage)
Sample
Force sensingtuning fork
Nano LED
CdSe nanoparticle
Figure 2. CdSe nanoparticles were trapped at the tip
Polarization measurement
Topographical image
SEM image
Distance measurement