Hostname: page-component-848d4c4894-hfldf Total loading time: 0 Render date: 2024-05-19T07:50:27.689Z Has data issue: false hasContentIssue false

Study of Gold Thin Films Evaporated on Polyethylene Naphthalate Films toward the Fabrication of Quantum Cross Devices

Published online by Cambridge University Press:  01 February 2011

Hideo Kaiju
Affiliation:
kaiju@es.hokudai.ac.jp, Research Institute for Electronic Science, Hokkaido University, Laboratory of Quantum Electronics, Kita 12 Nishi 6, Sapporo, 060-0812, Japan, +81-11-706-2878, +81-11-706-2883
Akito Ono
Affiliation:
aono@es.hokudai.ac.jp, Research Institute for Electronic Science, Hokkaido University, Laboratory of Quantum Electronics, Sapporo, 060-0812, Japan
Nobuyoshi Kawaguchi
Affiliation:
nkawa@es.hokudai.ac.jp, Research Institute for Electronic Science, Hokkaido University, Laboratory of Quantum Electronics, Sapporo, 060-0812, Japan
Kenji Kondo
Affiliation:
kkondo@es.hokudai.ac.jp, Research Institute for Electronic Science, Hokkaido University, Laboratory of Quantum Electronics, Sapporo, 060-0812, Japan
Akira Ishibashi
Affiliation:
i-akira@es.hokudai.ac.jp, Research Institute for Electronic Science, Hokkaido University, Laboratory of Quantum Electronics, Sapporo, 060-0812, Japan
Get access

Abstract

Molecular electronics devices continue to be pursued as a technology that offers the prospect of scaling device dimensions down to a few nanometers and also promote a practical introduction for high-density memory applications. One of several molecular devices is a cross-bar memory device fabricated by nanoimprint lithography process, which has achieved the production of 30-nm half-pitch patterning. However, today's production procedures such as nanoimprint lithography, optical lithography, and electron-beam lithography, do not allow for the resolution to achieve sub-10-nm line-width structures. Recently we have proposed a double nano-“baumkuchen” (DNB) structure, composed of two thin slices of alternating metal/insulator nano-“baumkuchen” as a lithography-free nano-structure fabrication technology. The DNB has potential application in a high-density memory device, the cross point of which can scale down to ultimately a few nanometers feature sizes because the pattering resolution is determined by the metal-deposition rate, ranging from 0.01 nm/s to the order of 0.1 nm/s. One element of the DNB structure is called a quantum cross (QC) device that consists of two metal nano-ribbons having edge-to-edge configuration. In the area of edge-to-edge QC devices there has been no experimental reports, meanwhile face-to-face devices such as cross-bar devices and spin tunneling devices, have been widely studied both theoretically and experimentally. In our present work, as the first experimental attempt toward the fabrication of QC devices, we have studied gold thin films evaporated on polyethylene naphtalate (PEN) organic films, which can be a candidate of metal/insulator part used for QC devices, by using the atomic force microscope (AFM). Au thin films were thermally evaporated on PEN films in the high vacuum chamber including the film-rolled-up system. The Au thickness was measured by a mechanical method using the stylus surface profiler and an optical method using the diode pumped solid state (DPSS) green laser. Surface morphologies of Au thin films on PEN films were analyzed by the AFM at room temperature. As the thickness of Au films evaporated on PEN films decreases from 20 nm to 5 nm, the AFM surface roughness is reduced from 4.8 nm down to 1.5 nm in the scanning area of 500~500 nm2. The Au grain size is 28.0-4.6 nm for 5-nm-thick Au films and 45.8-5.8 nm for 10-nm-thick Au films, respectively. As a result of the scaling investigation of the surface roughness, the surface roughness of 5-nm-thick Au films is 0.22 nm, corresponding to one atomic size, in the scanning scale of 5 nm. These experimental results indicate that Au thin films on PEN films are suitable as a candidate of metal/insulator(organic films) hybrid materials used for QC devices, and may open up a noble research field to clarify the electric characterization of QC devices using a few atoms or molecules leading to high-density memories.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Chen, J., Reed, M. A., Rawlett, A. M., and Tour, J. M., Science 286, 1550 (1999).Google Scholar
2. Chen, Y., Ohlberg, D. A. A., Li, X., Stewart, D. R., Williams, R. S., Jeppesen, J. O., Nielsen, K. A., Stoddard, J. F., Olynick, D. L., and Anderson, R., Appl. Phys. Lett. 82, 1610 (2003).Google Scholar
3. Wu, W., Jung, G.-Y., Olynick, D. L., Straznicky, J., Li, Z., Li, X., Ohlberg, D. A. A., Chen, Y., Wang, S. –Y., Liddle, J. A., Tong, W. M., Williams, R. S., Appl. Phys. A 80, 1173 (2005).Google Scholar
4. Jung, G. Y., Wu, W., Ganapathiappan, S., Ohlberg, D. A. A., Saifislam, M., Li, X., Olynick, D. L., Lee, H., Chen, Y., Wang, S. Y., Tong, W. M., Williams, R. S., Appl. Phys. A 81, 1331 (2005).Google Scholar
5. Rothschild, M., Bloomstein, T. M., Efremow, N. Jr, Fedynyshyn, T. H., Fritze, M., Pottebaum, I., and Switkes, M., MRS Bulletin 30, 942 (2005).Google Scholar
6. Fritze, M., Bloomstein, T. M., Tyrrell, B., and Rothschild, M., Solid State Tech. 49, 41 (2006).Google Scholar
7. Roberts, J., Bacuita, T., Bristol, R. L., Cao, H., Chandhok, M., Lee, S. H., Leeson, M., Liang, T., Panning, E., Rice, B. J., Shah, U., Shell, M., Yueh, W., and Zhang, G. J., Microelectron. Eng. 83, 672 (2006).Google Scholar
8. Silverman, P. J., J. Microlith., Microfab., Microsyst. 4, 011006 (2005).Google Scholar
9. Ishibashi, A., Proc. Int. Symp. on Nano Science and Technology, 44 (2004).Google Scholar
10. Kaiju, H., Ono, A., Kawaguchi, N., and Ishibashi, A., Jpn. J. Appl. Phys. 47, 244 (2008).Google Scholar
11. Ishibashi, A., Kaiju, H., Yamagata, Y., and Kawaguchi, N., Electron. Lett. 41, 735 (2005).Google Scholar
12. Kaiju, H., Kawaguchi, N., and Ishibashi, A., Rev. Sci. Instrum. 76, 085111 (2005).Google Scholar
13. Kondo, K. and Ishibashi, A.: Jpn. J. Appl. Phys. 45, 9137 (2006).Google Scholar
14. Kaiju, H., Kondo, K., and Ishibashi, A.: Mater. Res. Soc. Symp. Proc. 961, O5.5.1 (2007).Google Scholar
15. Bhushan, B., Ma, T., and Higashioji, T., J. Appl. Polym. Sci. 83, 2225 (2002).Google Scholar