JoVE Logo
Faculty Resource Center

Sign In

Summary

Abstract

Introduction

Protocol

Representative Results

Discussion

Acknowledgements

Materials

References

Engineering

Nanomoulding of Functional Materials, a Versatile Complementary Pattern Replication Method to Nanoimprinting

Published: January 23rd, 2013

DOI:

10.3791/50177

1Institute of Microengineering (IMT), Photovoltaics and Thin Film Electronics Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), 2Department of Electrical Engineering and Computer Sciences, University of California, Berkeley

We describe a nanomoulding technique which allows low-cost nanoscale patterning of functional materials, materials stacks and full devices. Nanomoulding can be performed on any nanoimprinting setup and can be applied to a wide range of materials and deposition processes.

We describe a nanomoulding technique which allows low-cost nanoscale patterning of functional materials, materials stacks and full devices. Nanomoulding combined with layer transfer enables the replication of arbitrary surface patterns from a master structure onto the functional material. Nanomoulding can be performed on any nanoimprinting setup and can be applied to a wide range of materials and deposition processes. In particular we demonstrate the fabrication of patterned transparent zinc oxide electrodes for light trapping applications in solar cells.

Nanopatterning has gained tremendous importance in many fields of nanotechnology and applied sciences. Pattern generation is the first step and may be accomplished by top-down approaches such as electron-beam lithography or bottom-up approaches based on self-assembly methods such as nanosphere lithography or block copolymer lithography 1. As important as pattern generation is pattern replication. Besides photolithography, nanoimprinting (Figure 1) has emerged as a promising alternative in particular suitable for high-throughput large-area nanoscale patterning at low cost 2-4. While photolithography requires a patterned ma....

Log in or to access full content. Learn more about your institution’s access to JoVE content here

1. Mould Fabrication

We use our home-built nanoimprinting setup for the fabrication of the negative mould following Ref. 6, but any alternative nanoimprinting setup will work fine. Alternatively a functionalized polydimethylsiloxane (PDMS) mould might also work.

  1. Fabricate or buy a suitable master carrying the nanoscale pattern to be transferred. In principle, any master suitable for nanoimprinting will do the job. We use a textured ZnO layer on a glass sheet (Schott, AF3.......

Log in or to access full content. Learn more about your institution’s access to JoVE content here

Figure 3 summarizes some illustrative examples of nanomoulded structures. A ZnO master structure grown by CVD on glass is shown in (a). The corresponding nanomoulded ZnO replica is shown in (d). Comparison of the local height (g) and angle (j) histograms extracted from AFM images reveal the high fidelity of the nanomoulding process. Analogous results are shown for a one-dimensional grating fabricated by interference lithography (b,e,h,k) and anodically textured aluminum (c,f,i,l).

Log in or to access full content. Learn more about your institution’s access to JoVE content here

Nanomoulding allows the transfer of nanopatterns on arbitrary functional materials. Comparison of the individual processing steps in Figure 1 and 2 reveals the close relationship between nanomoulding and nanoimprinting. The major difference between nanomoulding and nanoimprinting is the additional material deposition step in Figure 2e. The remaining process flow is identical. Nanomoulding can therefore be performed on any available nanoimprinting setup.

Log in or to access full content. Learn more about your institution’s access to JoVE content here

The authors thank M. Leboeuf for assistance with the AFM, W. Lee for the anodically textured aluminum master and the Swiss Federal Energy Office and the Swiss National Science Foundation for funding. A part of this work was carried out in the framework of the FP7 project "Fast Track" funded by the EC under grant agreement no 283501.

....

Log in or to access full content. Learn more about your institution’s access to JoVE content here

Name Company Catalog Number Comments
Name of the Reagent Company Catalogue Number Comments (optional)
Nanoimprinting resin Microresist Ormostamp  
(1H, 1H, 2H, 2H-Perfluoroctyl)-trichlorsilane, anti-adhesion agent Sigma Aldrich 448931-10G  
Glass slides Schott AF32 eco 0.5 mm
Polyethylene naphtalate (PEN) sheets Goodfellow ES361090 0.125 mm
(C2H5)2Zn Akzo Nobel    
Ag sputter target 4N Heraeus 81062165  
B2H6, SiH4, H2, B(CH3)3, PH3, CH4, CO2 Messer    
      EQUIPMENT
Nanoimprinting system Home-built    
LP-CVD system Home-built    
PVD system Leybold Univex 450 B  
PE-CVD reactor Indeotec Octopus I  
SEM JEOL JSM-7500 TFE  
AFM Digital Instruments Nanoscope 3100  

  1. Geissler, M., Xia, Y. Patterning: Principles and Some New Developments. Advanced Materials. 16 (15), 1249-1269 (2004).
  2. Guo, L. J. Nanoimprint Lithography: Methods and Material Requirements. Advanced Materials. 19, 495-513 (2007).
  3. Ahn, S. H., Guo, L. J. Large-Area Roll-to-Roll and Roll-to-Plate Nanoimprint Lithography: A Step toward High-Throughput. Application of Continuous Nanoimprinting. ACS Nano. 3 (8), 2304-2310 (2009).
  4. Battaglia, C., Escarré, J., et al. Nanoimprint Lithography for High-Efficiency Thin-Film Silicon Solar Cells. Nano Letters. 11, 661-665 (2011).
  5. Battaglia, C., Escarré, J., et al. Nanomoulding of Transparent Zinc Oxide Electrodes for Efficient Light Trapping in Solar Cells. Nature Photonics. 5, 535-538 (2012).
  6. Escarré, J., Söderström, K., et al. High Fidelity Transfer of Nanometric Random Textures by UV Embossing for Thin Film Solar Cells Applications. Solar Energy Materials & Solar Cells. 95, 881-886 (2011).
  7. Faÿ, S., Feitknecht, L., Schlüchter, R., Kroll, U., Vallat-Sauvain, E., Shah, A. Rough ZnO layers by LP-CVD process and their effect in improving performances of amorphous and microcrystalline silicon solar cells. Solar Energy Materials and Solar Cells. 90, 2960-2967 (2006).
  8. Zhao, X. -. M., Xia, Y., Whitesides, G. M. Fabrication of Three-Dimensional Micro-Structures: Microtransfer Molding. Advanced Materials. 8, 837-840 (1996).
  9. Hampton, M. J., Williams, S. S., et al. The Patterning of Sub-500 nm Inorganic Oxide Structures. Advanced Materials. 20, 2667-2673 (2008).
  10. Bass, J. D., Schaper, C. D., et al. Transfer Molding of Nanoscale Oxides Using Water-Soluble Templates. ACS Nano. 5 (5), 4065-4072 (2011).
  11. Escarré, J., Nicolay, S., et al. Nanomoulded front ZnO contacts for thin film silicon solar cell applications. , (2012).
  12. Sontheimer, T., Rudigier-Voigt, E., Bockmeyer, M., Klimm, C., Schubert-Bischoff, P., Becker, C., Rech, B. Large-area fabrication of equidistant free-standing Si crystals on nanoimprinted glass. Phys. Status Solidi. RRL. 5, 376-379 (2011).

This article has been published

Video Coming Soon

JoVE Logo

Privacy

Terms of Use

Policies

Research

Education

ABOUT JoVE

Copyright © 2024 MyJoVE Corporation. All rights reserved