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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 21 — Oct. 21, 2013
  • pp: 24460–24467
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Multi-level surface enhanced Raman scattering using AgOx thin film

Ming Lun Tseng, Chia Min Chang, Bo Han Cheng, Pin Chieh Wu, Kuang Sheng Chung, Min-Kai Hsiao, Hsin Wei Huang, Ding-Wei Huang, Hai-Pang Chiang, Pui Tak Leung, and Din Ping Tsai  »View Author Affiliations


Optics Express, Vol. 21, Issue 21, pp. 24460-24467 (2013)
http://dx.doi.org/10.1364/OE.21.024460


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Abstract

Ag nanostructures with surface-enhanced Raman scattering (SERS) activities have been fabricated by applying laser-direct writing (LDW) technique on silver oxide (AgOx) thin films. By controlling the laser powers, multi-level Raman imaging of organic molecules adsorbed on the nanostructures has been observed. This phenomenon is further investigated by atomic-force microscopy and electromagnetic calculation. The SERS-active nanostructure is also fabricated on transparent and flexible substrate to demonstrate our promising strategy for the development of novel and low-cost sensing chip.

© 2013 Optical Society of America

1. Introduction

2. Experimental

AgOx thin films are reactively sputtered on transparent BK7 substrates (thickness = 1.5 mm) by RF-magnetron sputtering machine (Shibaura Mechatronics Corp.) in an Ar/O2 (flow ratio = 10/25) mixed-gas atmosphere (pressure of the gas mixture = 5 × 10−1 Pa). In the fabrication of Ag nanostructures, the as-deposited AgOx thin film is mounted on the computer-controlled three-dimensional stage (Mad City Lab. Inc.) of the fs-laser system. A Ti:Sapphire fs-laser oscillator (Coherent Inc.) emitting at 800 nm, with a repetition rate and a pulse width of 80 MHz and 140 fs, respectively, is focused by an oil-immersion objective lens (Zeiss Plan-Apochromat, 100 × , working distance = 0.17 mm, NA = 1.4) through the substrate and illuminated on the AgOx thin film. The incident laser power is adjusted by an attenuator. Before enter the objective lens, the laser beam is expended to a diameter of 6 mm, and is made circularly polarized using a λ/4 waveplate. In this work, the applied powers on the thin film are 21 mW, 11 mW, and 7 mW, which the corresponding fluences are 18.9 mJ/cm2, 9.9 mJ/cm2, and 6.3 mJ/cm2, respectively.

Characterization of the Ag nanostructures is carried out using an atomic force microscope (Asylum Research, MFP-3D) for surface morphology. For Raman spectroscopy and imaging, a WITec CRM200 scanning confocal Raman microscope with 532 nm-wavelength semiconductor laser for excitation is employed. The excitation laser beam is focused with a 100 × objective lens (NA = 0.95) on a Nikon Plan microscope. In Raman measurement, Rhodamine 6G (R6G) is used to evaluate the SERS efficiencies of the samples. In the literature, R6G has been widely utilized for studying different SERS-active structures previously, and the Raman vibration of R6G has been studied comprehensively [8

8. K. K. Strelau, T. Schüler, R. Möller, W. Fritzsche, and J. Popp, “Novel bottom-up SERS substrates for quantitative and parallelized analytics,” ChemPhysChem 11(2), 394–398 (2010). [CrossRef] [PubMed]

, 27

27. Y. Nagai, T. Yamaguchi, and K. Kajikawa, “Angular-resolved polarized surface enhanced raman spectroscopy,” J. Phys. Chem. C 116(17), 9716–9723 (2012). [CrossRef]

30

30. P. Hildebrandt and M. Stockburger, “Surface-enhanced resonance raman-spectroscopy of rhodamine-6g adsorbed on colloidal silver,” J. Phys. Chem. 88(24), 5935–5944 (1984). [CrossRef]

]. Drops of 10−5 M R6G solution are put on the sample by a dropper, and purged by pure N2 gas. The sample is subsequently mounted on the piezostage of the Raman system and point-by-point scanned (step size = 1μm, exposure time = 1s) under excitation, while the corresponding Raman spectrum of each point is acquired in the scanning. The laser power on the sample is kept at 0.1 mW to avoid undesired laser-induced reduction of AgOx and sample damage.

3. Results and discussions

3.1 Relations between SERS and processing laser powers on AgOx

Figure 1(a)
Fig. 1 (a) Optical reflection image of laser-generated Ag nanostructures made with laser powers 21 mW, 11 mW, 7 mW, respectively and (b) the corresponding Raman intensity map of R6G on the Ag nanostructures. The Raman intensity map is obtained from integrating spectral intensity of the R6G Raman peak ranging from 598 to 623 cm−1. The two images are shown on the same scale. (c) Raman spectra of R6G adsorbed on various zones of laser-processed AgOx thin film. The up insert shows the molecular structure of R6G molecule, and the button insert is the magnified Raman spectrum of R6G molecules obtained from the region of unprocessed AgOx thin film.
is the optical reflection image of the laser-processed AgOx thin film. Three rectangular zones on an as-deposited AgOx thin film are treated by fs-laser beam in the form of raster scanning with various fs-laser powers. The applied powers on the thin film are 21 mW, 11 mW, and 7 mW, respectively, to write parallel lines with a separation of 1 µm (scanning rate ~33.3 μm/s). In the optical image, optical reflectance of the processed area is apparently raised in comparison with the untreated one, indicating the obviously metallic property of the processed area. No obvious difference in reflectivity is observed among the regions processed with laser powers of 21 and 11 mW, and the reflectivity at the 7-mW region being slightly smaller. Even the reflections are not seen to vary with laser powers significantly, the Raman enhancements in the three regions are rather different. Figure 1(b) is the corresponding Raman intensity map image of R6G adsorbed on the area. In Raman intensity map, the regions displayed in brighter color are with higher intensity of selected Raman peak. The Raman image of intensity map shows the spatial distribution of Raman intensity integrated over the peak in the regime of 598-623 cm−1, which is associated with the in-plane bending of the xanthene ring in the R6G molecule [30

30. P. Hildebrandt and M. Stockburger, “Surface-enhanced resonance raman-spectroscopy of rhodamine-6g adsorbed on colloidal silver,” J. Phys. Chem. 88(24), 5935–5944 (1984). [CrossRef]

]. Four obvious levels of R6G Raman intensity can be observed in the image: Raman intensity at the 21-mW processed region is brighter than those at 11-mW and 7-mW, and the Raman intensity recorded from laser-processed regions are all stronger than the unprocessed one.

Figure 1(c) shows the average Raman spectra obtained from various regions on processed AgOx thin film. Peaks at 611, 770, 1358, 1507, and 1647 cm−1 corresponding to R6G Raman vibration modes can be identified at the spectra acquired from laser processing regions [30

30. P. Hildebrandt and M. Stockburger, “Surface-enhanced resonance raman-spectroscopy of rhodamine-6g adsorbed on colloidal silver,” J. Phys. Chem. 88(24), 5935–5944 (1984). [CrossRef]

]. The average intensities of Raman vibration peak at the wave number 611 cm−1 acquired from regions processed with laser of 21 mW, 11 mW, 7 mW, and from unprocessed region are found to be around 15900, 12120, 600, and 340 CCD counts (arbitrary unit), respectively. In comparison with the unprocessed region, the Raman signal of R6G is enhanced more than 46-fold in the 21-mW laser-processed region. The enhancements of the other main vibrational modes of R6G at 770, 1358, 1507, and 1647 are 42-, 43-, 40-, 39-fold, respectively. The Raman intensities of R6G molecules are increased with increasing processing powers, indicating that SERS capability of processed AgOx thin film depends significantly on the incident laser power.

3.2 Fabrication of SERS surface on transparent and flexible substrate

The SERS-active Ag nanostructures can be made on the optical transparent and flexible substrate by our proposed strategy. AgOx thin film (thickness: 15 nm) is reactively sputtered on the polycarbonate substrate (thickness = 0.6mm, refractive index~1.584). Here a 20 × Zesis Epiplan lens is utilized. For avoiding the laser-induced damage of the polycarbonate substrate, a transparent dielectric ZnS-SiO2 film (composition ratio: ZnS 80% and SiO2 20%) as protective layer is employed. ZnS-SiO2 film has been widely used in the fields of optical data storage for protecting the recording media because of its high flexibility, optical transparency, low thermal conductivity, and thermal stability [35

35. D. V. Tsu and T. Ohta, “Mechanism of properties of noble ZnS-SiO2 protection layer for phase change optical disk media,” Jpn. J. Appl. Phys. 45(8A), 6294–6307 (2006). [CrossRef]

38

38. C. M. Chang, C. H. Chu, M. L. Tseng, H. P. Chiang, M. Mansuripur, and D. P. Tsai, “Local electrical characterization of laser-recorded phase-change marks on amorphous Ge2Sb2Te5 thin films,” Opt. Express 19(10), 9492–9504 (2011). [CrossRef] [PubMed]

]. Stacked films of 200-nm-thick ZnS-SiO2 and 15-nm-thick AgOx are sputtered on the polycarbonate substrate. This layered structure is highly transparent and flexible. After laser processing (power: 11mW, scanning rate: 55 μm/s, spacing between scanning lines: 250 nm) Ag nanostructures are formed on the surface. As shown in Fig. 4
Fig. 4 Raman spectra of R6G molecules obtained from the laser-generated Ag nanostructure and as-deposited AgOx thin film on optical transparent and flexible substrate. The Raman image of intensity map shows the spatial distribution of Raman intensity integrated over the peak in the regime of 598-623 cm−1
, obvious Raman enhancement for R6G is obtained at the laser-generated Ag nanostructure on flexible substrate.

4. Conclusion

We have reported an efficient method to fabricate SERS-active Ag nanostructures by using laser-direct writing to treat sputtered AgOx thin films. The multi-level Raman enhancements of R6G molecules observed in our experiments have their origins from the different average sizes of the generated Ag nanoparticles on the surfaces. These sizes can be controlled by the laser power, leading to different plasmon-active areas on the fixed probing area. In addition, proof-of-principle demonstration of making SERS-active structures on the flexible substrate is also presented. The present methodology is thus very promising for future applications of SERS to sensing and fabrication of lab-on-chip systems.

Acknowledgments

The authors gratefully acknowledge the financial support of the National Science Council of Taiwan (NSC 102-2745-M-002-005-ASP, 102-2911-I-002-505, 100-2112-M-019-003-MY3). They are also grateful to National Center for Theoretical Sciences, Taipei Office, Molecular Imaging Center of National Taiwan University, National Center for High-Performance Computing, Taiwan, and Research Center for Applied Sciences, Academia Sinica, Taiwan for their support.

References

1.

D. P. Tsai, J. Kovacs, Z. H. Wang, M. Moskovits, V. M. Shalaev, J. S. Suh, and R. Botet, “Photon scanning tunneling microscopy images of optical excitations of fractal metal colloid clusters,” Phys. Rev. Lett. 72(26), 4149–4152 (1994). [CrossRef] [PubMed]

2.

C. E. Talley, J. B. Jackson, C. Oubre, N. K. Grady, C. W. Hollars, S. M. Lane, T. R. Huser, P. Nordlander, and N. J. Halas, “Surface-enhanced raman scattering from individual au nanoparticles and nanoparticle dimer substrates,” Nano Lett. 5(8), 1569–1574 (2005). [CrossRef] [PubMed]

3.

M. Moskovits, “Surface-enhanced spectroscopy,” Rev. Mod. Phys. 57(3), 783–826 (1985). [CrossRef]

4.

A. Barhoumi, D. Zhang, F. Tam, and N. J. Halas, “Surface-enhanced Raman spectroscopy of DNA,” J. Am. Chem. Soc. 130(16), 5523–5529 (2008). [CrossRef] [PubMed]

5.

X. Qian, X.-H. Peng, D. O. Ansari, Q. Yin-Goen, G. Z. Chen, D. M. Shin, L. Yang, A. N. Young, M. D. Wang, and S. Nie, “In vivo tumor targeting and spectroscopic detection with surface-enhanced raman nanoparticle tags,” Nat. Biotechnol. 26(1), 83–90 (2008). [CrossRef] [PubMed]

6.

A. Chou, E. Jaatinen, R. Buividas, G. Seniutinas, S. Juodkazis, E. L. Izake, and P. M. Fredericks, “SERS substrate for detection of explosives,” Nanoscale 4(23), 7419–7424 (2012). [CrossRef] [PubMed]

7.

W.-C. Lin, H.-C. Jen, C.-L. Chen, D.-F. Hwang, R. Chang, J.-S. Hwang, and H.-P. Chiang, “SERS study of tetrodotoxin (TTX) by using silver nanoparticle arrays,” Plasmonics 4(2), 187–192 (2009). [CrossRef]

8.

K. K. Strelau, T. Schüler, R. Möller, W. Fritzsche, and J. Popp, “Novel bottom-up SERS substrates for quantitative and parallelized analytics,” ChemPhysChem 11(2), 394–398 (2010). [CrossRef] [PubMed]

9.

C. L. Haynes and R. P. Van Duyne, “Nanosphere lithography: A versatile nanofabrication tool for studies of size-dependent nanoparticle optics,” J. Phys. Chem. B 105(24), 5599–5611 (2001). [CrossRef]

10.

H.-L. Huang, C. F. Chou, S. H. Shiao, Y.-C. Liu, J.-J. Huang, S. U. Jen, and H.-P. Chiang, “Surface plasmon-enhanced photoluminescence of DCJTB by using silver nanoparticle arrays,” Opt. Express 21(S5), A901–A908 (2013). [CrossRef]

11.

J. Neddersen, G. Chumanov, and T. M. Cotton, “Laser-ablation of metals - a new method for preparing SERS active colloids,” Appl. Spectrosc. 47(12), 1959–1964 (1993). [CrossRef]

12.

X. Ling, L. Xie, Y. Fang, H. Xu, H. Zhang, J. Kong, M. S. Dresselhaus, J. Zhang, and Z. Liu, “Can graphene be used as a substrate for Raman enhancement?” Nano Lett. 10(2), 553–561 (2010). [CrossRef] [PubMed]

13.

T. C. Chong, M. H. Hong, and L. P. Shi, “Laser precision engineering: From microfabrication to nanoprocessing,” Laser Photonics Rev. 4(1), 123–143 (2010). [CrossRef]

14.

M. Malinauskas, P. Danilevičius, and S. Juodkazis, “Three-dimensional micro-/nano-structuring via direct write polymerization with picosecond laser pulses,” Opt. Express 19(6), 5602–5610 (2011). [CrossRef] [PubMed]

15.

N. R. Han, Z. C. Chen, C. S. Lim, B. Ng, and M. H. Hong, “Broadband multi-layer terahertz metamaterials fabrication and characterization on flexible substrates,” Opt. Express 19(8), 6990–6998 (2011). [CrossRef] [PubMed]

16.

K. Masui, S. Shoji, K. Asaba, T. C. Rodgers, F. Jin, X. M. Duan, and S. Kawata, “Laser fabrication of Au nanorod aggregates microstructures assisted by two-photon polymerization,” Opt. Express 19(23), 22786–22796 (2011). [CrossRef] [PubMed]

17.

C.-H. Lin, L. Jiang, Y.-H. Chai, H. Xiao, S.-J. Chen, and H.-L. Tsai, “One-step fabrication of nanostructures by femtosecond laser for surface-enhanced raman scattering,” Opt. Express 17(24), 21581–21589 (2009). [CrossRef] [PubMed]

18.

A. Takami, H. Kurita, and S. Koda, “Laser-induced size reduction of noble metal particles,” J. Phys. Chem. B 103(8), 1226–1232 (1999). [CrossRef]

19.

M. L. Tseng, Y.-W. Huang, M.-K. Hsiao, H. W. Huang, H. M. Chen, Y. L. Chen, C. H. Chu, N.-N. Chu, Y. J. He, C. M. Chang, W. C. Lin, D.-W. Huang, H.-P. Chiang, R.-S. Liu, G. Sun, and D. P. Tsai, “Fast fabrication of a Ag nanostructure substrate using the femtosecond laser for broad-band and tunable plasmonic enhancement,” ACS Nano 6(6), 5190–5197 (2012). [CrossRef] [PubMed]

20.

W. Zhu, D. Wang, and K. B. Crozier, “Direct observation of beamed Raman scattering,” Nano Lett. 12(12), 6235–6243 (2012). [CrossRef] [PubMed]

21.

A. J. Pasquale, B. M. Reinhard, and L. Dal Negro, “Concentric necklace nanolenses for optical near-field focusing and enhancement,” ACS Nano 6(5), 4341–4348 (2012). [CrossRef] [PubMed]

22.

S. Ayas, H. Güner, B. Türker, O. O. Ekiz, F. Dirisaglik, A. K. Okyay, and A. Dâna, “Raman enhancement on a broadband meta-surface,” ACS Nano 6(8), 6852–6861 (2012). [CrossRef] [PubMed]

23.

D. He, B. Hu, Q.-F. Yao, K. Wang, and S.-H. Yu, “Large-scale synthesis of flexible free-standing SERS substrates with high sensitivity: electrospun PVA nanofibers embedded with controlled alignment of silver nanoparticles,” ACS Nano 3(12), 3993–4002 (2009). [CrossRef] [PubMed]

24.

W. Xu, X. Ling, J. Xiao, M. S. Dresselhaus, J. Kong, H. Xu, Z. Liu, and J. Zhang, “Surface enhanced Raman spectroscopy on a flat graphene surface,” Proc. Natl. Acad. Sci. U.S.A. 109(24), 9281–9286 (2012). [CrossRef] [PubMed]

25.

A. J. Chung, Y. S. Huh, and D. Erickson, “Large area flexible SERS active substrates using engineered nanostructures,” Nanoscale 3(7), 2903–2908 (2011). [CrossRef] [PubMed]

26.

X. Liu, C. Zong, K. Ai, W. He, and L. Lu, “Engineering natural materials as surface-enhanced raman spectroscopy substrates for in situ molecular sensing,” ACS Appl. Mater. Interfaces 4(12), 6599–6608 (2012). [CrossRef] [PubMed]

27.

Y. Nagai, T. Yamaguchi, and K. Kajikawa, “Angular-resolved polarized surface enhanced raman spectroscopy,” J. Phys. Chem. C 116(17), 9716–9723 (2012). [CrossRef]

28.

A. Kocabas, G. Ertas, S. S. Senlik, and A. Aydinli, “Plasmonic band gap structures for surface-enhanced Raman scattering,” Opt. Express 16(17), 12469–12477 (2008). [CrossRef] [PubMed]

29.

W.-C. Lin, S.-H. Huang, C.-L. Chen, C.-C. Chen, D. P. Tsai, and H.-P. Chiang, “Controlling SERS intensity by tuning the size and height of a silver nanoparticle array,” Appl. Phys., A Mater. Sci. Process. 101(1), 185–189 (2010). [CrossRef]

30.

P. Hildebrandt and M. Stockburger, “Surface-enhanced resonance raman-spectroscopy of rhodamine-6g adsorbed on colloidal silver,” J. Phys. Chem. 88(24), 5935–5944 (1984). [CrossRef]

31.

S. Inasawa, M. Sugiyama, and S. Koda, “Size controlled formation of gold nanoparticles using photochemical grwoth and photothermal size reduction by 308 nm laser pulses,” Jpn. J. Appl. Phys. 42(10), 6705–6712 (2003). [CrossRef]

32.

T.-C. Peng, W.-C. Lin, C.-W. Chen, D. P. Tsai, and H.-P. Chiang, “Enhanced sensitivity of surface plasmon resonance phase-interrogation biosensor by using silver nanoparticles,” Plasmonics 6(1), 29–34 (2011). [CrossRef]

33.

A. F. Oskooi, D. Roundy, M. Ibanescu, P. Bermel, J. D. Joannopoulos, and S. G. Johnson, “MEEP: A flexible free-software package for electromagnetic simulations by the FDTD method,” Comput. Phys. Commun. 181(3), 687–702 (2010). [CrossRef]

34.

A. D. Rakic, A. B. Djurisic, J. M. Elazar, and M. L. Majewski, “Optical properties of metallic films for vertical-cavity optoelectronic devices,” Appl. Opt. 37(22), 5271–5283 (1998). [CrossRef] [PubMed]

35.

D. V. Tsu and T. Ohta, “Mechanism of properties of noble ZnS-SiO2 protection layer for phase change optical disk media,” Jpn. J. Appl. Phys. 45(8A), 6294–6307 (2006). [CrossRef]

36.

C. H. Chu, C. D. Shiue, H. W. Cheng, M. L. Tseng, H.-P. Chiang, M. Mansuripur, and D. P. Tsai, “Laser-induced phase transitions of Ge2Sb2Te5 thin films used in optical and electronic data storage and in thermal lithography,” Opt. Express 18(17), 18383–18393 (2010). [CrossRef] [PubMed]

37.

S. K. Lin, I. C. Lin, and D. P. Tsai, “Characterization of nano recorded marks at different writing strategies on phase-change recording layer of optical disks,” Opt. Express 14(10), 4452–4458 (2006). [CrossRef] [PubMed]

38.

C. M. Chang, C. H. Chu, M. L. Tseng, H. P. Chiang, M. Mansuripur, and D. P. Tsai, “Local electrical characterization of laser-recorded phase-change marks on amorphous Ge2Sb2Te5 thin films,” Opt. Express 19(10), 9492–9504 (2011). [CrossRef] [PubMed]

OCIS Codes
(140.3390) Lasers and laser optics : Laser materials processing
(310.3840) Thin films : Materials and process characterization
(220.4241) Optical design and fabrication : Nanostructure fabrication
(250.5403) Optoelectronics : Plasmonics
(240.6695) Optics at surfaces : Surface-enhanced Raman scattering

ToC Category:
Thin Films

History
Original Manuscript: July 24, 2013
Revised Manuscript: September 16, 2013
Manuscript Accepted: September 24, 2013
Published: October 7, 2013

Citation
Ming Lun Tseng, Chia Min Chang, Bo Han Cheng, Pin Chieh Wu, Kuang Sheng Chung, Min-Kai Hsiao, Hsin Wei Huang, Ding-Wei Huang, Hai-Pang Chiang, Pui Tak Leung, and Din Ping Tsai, "Multi-level surface enhanced Raman scattering using AgOx thin film," Opt. Express 21, 24460-24467 (2013)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-21-21-24460


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References

  1. D. P. Tsai, J. Kovacs, Z. H. Wang, M. Moskovits, V. M. Shalaev, J. S. Suh, and R. Botet, “Photon scanning tunneling microscopy images of optical excitations of fractal metal colloid clusters,” Phys. Rev. Lett.72(26), 4149–4152 (1994). [CrossRef] [PubMed]
  2. C. E. Talley, J. B. Jackson, C. Oubre, N. K. Grady, C. W. Hollars, S. M. Lane, T. R. Huser, P. Nordlander, and N. J. Halas, “Surface-enhanced raman scattering from individual au nanoparticles and nanoparticle dimer substrates,” Nano Lett.5(8), 1569–1574 (2005). [CrossRef] [PubMed]
  3. M. Moskovits, “Surface-enhanced spectroscopy,” Rev. Mod. Phys.57(3), 783–826 (1985). [CrossRef]
  4. A. Barhoumi, D. Zhang, F. Tam, and N. J. Halas, “Surface-enhanced Raman spectroscopy of DNA,” J. Am. Chem. Soc.130(16), 5523–5529 (2008). [CrossRef] [PubMed]
  5. X. Qian, X.-H. Peng, D. O. Ansari, Q. Yin-Goen, G. Z. Chen, D. M. Shin, L. Yang, A. N. Young, M. D. Wang, and S. Nie, “In vivo tumor targeting and spectroscopic detection with surface-enhanced raman nanoparticle tags,” Nat. Biotechnol.26(1), 83–90 (2008). [CrossRef] [PubMed]
  6. A. Chou, E. Jaatinen, R. Buividas, G. Seniutinas, S. Juodkazis, E. L. Izake, and P. M. Fredericks, “SERS substrate for detection of explosives,” Nanoscale4(23), 7419–7424 (2012). [CrossRef] [PubMed]
  7. W.-C. Lin, H.-C. Jen, C.-L. Chen, D.-F. Hwang, R. Chang, J.-S. Hwang, and H.-P. Chiang, “SERS study of tetrodotoxin (TTX) by using silver nanoparticle arrays,” Plasmonics4(2), 187–192 (2009). [CrossRef]
  8. K. K. Strelau, T. Schüler, R. Möller, W. Fritzsche, and J. Popp, “Novel bottom-up SERS substrates for quantitative and parallelized analytics,” ChemPhysChem11(2), 394–398 (2010). [CrossRef] [PubMed]
  9. C. L. Haynes and R. P. Van Duyne, “Nanosphere lithography: A versatile nanofabrication tool for studies of size-dependent nanoparticle optics,” J. Phys. Chem. B105(24), 5599–5611 (2001). [CrossRef]
  10. H.-L. Huang, C. F. Chou, S. H. Shiao, Y.-C. Liu, J.-J. Huang, S. U. Jen, and H.-P. Chiang, “Surface plasmon-enhanced photoluminescence of DCJTB by using silver nanoparticle arrays,” Opt. Express21(S5), A901–A908 (2013). [CrossRef]
  11. J. Neddersen, G. Chumanov, and T. M. Cotton, “Laser-ablation of metals - a new method for preparing SERS active colloids,” Appl. Spectrosc.47(12), 1959–1964 (1993). [CrossRef]
  12. X. Ling, L. Xie, Y. Fang, H. Xu, H. Zhang, J. Kong, M. S. Dresselhaus, J. Zhang, and Z. Liu, “Can graphene be used as a substrate for Raman enhancement?” Nano Lett.10(2), 553–561 (2010). [CrossRef] [PubMed]
  13. T. C. Chong, M. H. Hong, and L. P. Shi, “Laser precision engineering: From microfabrication to nanoprocessing,” Laser Photonics Rev.4(1), 123–143 (2010). [CrossRef]
  14. M. Malinauskas, P. Danilevičius, and S. Juodkazis, “Three-dimensional micro-/nano-structuring via direct write polymerization with picosecond laser pulses,” Opt. Express19(6), 5602–5610 (2011). [CrossRef] [PubMed]
  15. N. R. Han, Z. C. Chen, C. S. Lim, B. Ng, and M. H. Hong, “Broadband multi-layer terahertz metamaterials fabrication and characterization on flexible substrates,” Opt. Express19(8), 6990–6998 (2011). [CrossRef] [PubMed]
  16. K. Masui, S. Shoji, K. Asaba, T. C. Rodgers, F. Jin, X. M. Duan, and S. Kawata, “Laser fabrication of Au nanorod aggregates microstructures assisted by two-photon polymerization,” Opt. Express19(23), 22786–22796 (2011). [CrossRef] [PubMed]
  17. C.-H. Lin, L. Jiang, Y.-H. Chai, H. Xiao, S.-J. Chen, and H.-L. Tsai, “One-step fabrication of nanostructures by femtosecond laser for surface-enhanced raman scattering,” Opt. Express17(24), 21581–21589 (2009). [CrossRef] [PubMed]
  18. A. Takami, H. Kurita, and S. Koda, “Laser-induced size reduction of noble metal particles,” J. Phys. Chem. B103(8), 1226–1232 (1999). [CrossRef]
  19. M. L. Tseng, Y.-W. Huang, M.-K. Hsiao, H. W. Huang, H. M. Chen, Y. L. Chen, C. H. Chu, N.-N. Chu, Y. J. He, C. M. Chang, W. C. Lin, D.-W. Huang, H.-P. Chiang, R.-S. Liu, G. Sun, and D. P. Tsai, “Fast fabrication of a Ag nanostructure substrate using the femtosecond laser for broad-band and tunable plasmonic enhancement,” ACS Nano6(6), 5190–5197 (2012). [CrossRef] [PubMed]
  20. W. Zhu, D. Wang, and K. B. Crozier, “Direct observation of beamed Raman scattering,” Nano Lett.12(12), 6235–6243 (2012). [CrossRef] [PubMed]
  21. A. J. Pasquale, B. M. Reinhard, and L. Dal Negro, “Concentric necklace nanolenses for optical near-field focusing and enhancement,” ACS Nano6(5), 4341–4348 (2012). [CrossRef] [PubMed]
  22. S. Ayas, H. Güner, B. Türker, O. O. Ekiz, F. Dirisaglik, A. K. Okyay, and A. Dâna, “Raman enhancement on a broadband meta-surface,” ACS Nano6(8), 6852–6861 (2012). [CrossRef] [PubMed]
  23. D. He, B. Hu, Q.-F. Yao, K. Wang, and S.-H. Yu, “Large-scale synthesis of flexible free-standing SERS substrates with high sensitivity: electrospun PVA nanofibers embedded with controlled alignment of silver nanoparticles,” ACS Nano3(12), 3993–4002 (2009). [CrossRef] [PubMed]
  24. W. Xu, X. Ling, J. Xiao, M. S. Dresselhaus, J. Kong, H. Xu, Z. Liu, and J. Zhang, “Surface enhanced Raman spectroscopy on a flat graphene surface,” Proc. Natl. Acad. Sci. U.S.A.109(24), 9281–9286 (2012). [CrossRef] [PubMed]
  25. A. J. Chung, Y. S. Huh, and D. Erickson, “Large area flexible SERS active substrates using engineered nanostructures,” Nanoscale3(7), 2903–2908 (2011). [CrossRef] [PubMed]
  26. X. Liu, C. Zong, K. Ai, W. He, and L. Lu, “Engineering natural materials as surface-enhanced raman spectroscopy substrates for in situ molecular sensing,” ACS Appl. Mater. Interfaces4(12), 6599–6608 (2012). [CrossRef] [PubMed]
  27. Y. Nagai, T. Yamaguchi, and K. Kajikawa, “Angular-resolved polarized surface enhanced raman spectroscopy,” J. Phys. Chem. C116(17), 9716–9723 (2012). [CrossRef]
  28. A. Kocabas, G. Ertas, S. S. Senlik, and A. Aydinli, “Plasmonic band gap structures for surface-enhanced Raman scattering,” Opt. Express16(17), 12469–12477 (2008). [CrossRef] [PubMed]
  29. W.-C. Lin, S.-H. Huang, C.-L. Chen, C.-C. Chen, D. P. Tsai, and H.-P. Chiang, “Controlling SERS intensity by tuning the size and height of a silver nanoparticle array,” Appl. Phys., A Mater. Sci. Process.101(1), 185–189 (2010). [CrossRef]
  30. P. Hildebrandt and M. Stockburger, “Surface-enhanced resonance raman-spectroscopy of rhodamine-6g adsorbed on colloidal silver,” J. Phys. Chem.88(24), 5935–5944 (1984). [CrossRef]
  31. S. Inasawa, M. Sugiyama, and S. Koda, “Size controlled formation of gold nanoparticles using photochemical grwoth and photothermal size reduction by 308 nm laser pulses,” Jpn. J. Appl. Phys.42(10), 6705–6712 (2003). [CrossRef]
  32. T.-C. Peng, W.-C. Lin, C.-W. Chen, D. P. Tsai, and H.-P. Chiang, “Enhanced sensitivity of surface plasmon resonance phase-interrogation biosensor by using silver nanoparticles,” Plasmonics6(1), 29–34 (2011). [CrossRef]
  33. A. F. Oskooi, D. Roundy, M. Ibanescu, P. Bermel, J. D. Joannopoulos, and S. G. Johnson, “MEEP: A flexible free-software package for electromagnetic simulations by the FDTD method,” Comput. Phys. Commun.181(3), 687–702 (2010). [CrossRef]
  34. A. D. Rakic, A. B. Djurisic, J. M. Elazar, and M. L. Majewski, “Optical properties of metallic films for vertical-cavity optoelectronic devices,” Appl. Opt.37(22), 5271–5283 (1998). [CrossRef] [PubMed]
  35. D. V. Tsu and T. Ohta, “Mechanism of properties of noble ZnS-SiO2 protection layer for phase change optical disk media,” Jpn. J. Appl. Phys.45(8A), 6294–6307 (2006). [CrossRef]
  36. C. H. Chu, C. D. Shiue, H. W. Cheng, M. L. Tseng, H.-P. Chiang, M. Mansuripur, and D. P. Tsai, “Laser-induced phase transitions of Ge2Sb2Te5 thin films used in optical and electronic data storage and in thermal lithography,” Opt. Express18(17), 18383–18393 (2010). [CrossRef] [PubMed]
  37. S. K. Lin, I. C. Lin, and D. P. Tsai, “Characterization of nano recorded marks at different writing strategies on phase-change recording layer of optical disks,” Opt. Express14(10), 4452–4458 (2006). [CrossRef] [PubMed]
  38. C. M. Chang, C. H. Chu, M. L. Tseng, H. P. Chiang, M. Mansuripur, and D. P. Tsai, “Local electrical characterization of laser-recorded phase-change marks on amorphous Ge2Sb2Te5 thin films,” Opt. Express19(10), 9492–9504 (2011). [CrossRef] [PubMed]

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