Formation of ultrasmooth thin silver films by pulsed laser deposition
- PDF / 660,057 Bytes
- 4 Pages / 612 x 792 pts (letter) Page_size
- 75 Downloads / 291 Views
ACE AND THIN FILMS
Formation of Ultrasmooth Thin Silver Films by Pulsed Laser Deposition I. A. Kuznetsov, M. Ya. Garaeva, D. A. Mamichev, Yu. V. Grishchenko, and M. L. Zanaveskin National Research Centre “Kurchatov Institute”, NBIC Center, Moscow, 123182 Russia email: [email protected] Received November 29, 2012
Abstract—Ultrasmooth thin silver films have been formed on a quartz substrate with a buffer yttrium oxide layer by pulsed laser deposition. The dependence of the surface morphology of the film on the gas (N2) pres sure in the working chamber and laser pulse energy is investigated. It is found that the conditions of film growth are optimal at a gas pressure of 10–2 Torr and lowest pulse energy. The silver films formed under these conditions on a quartz substrate with an initial surface roughness of 0.3 nm had a surface roughness of 0.36 nm. These films can be used as a basis for various optoelectronics and nanoplasmonics elements. DOI: 10.1134/S1063774513030097
INTRODUCTION Today nanoplasmonics is a rapidly developing field of research that is caused by the discovery of new prop erties of materials related to the excitation of surface plasmons and active investigations of metamaterials [1, 2]. Surface plasmons are strongly localized at the interface and possess a number of features allowing these evanescent waves to be used to design various nanoelectronic and optoelectronic devices. Devices based on the surface plasmon resonance phenomenon (selective filters, modulators, sensors, etc.) are designed using either thinfilm metal–insulator struc tures or nanostructures on their basis. One of the most widespread metals used in these structures is silver, which has suitable optical properties for the effective excitation of surface plasmons in the visible spectral range [3]. Since surface plasmons are localized at the interface they are very sensitive to various inhomoge neities and defects on the film surface. Inhomogene ities lead to scattering and damping of the surface waves and, as a consequence, deteriorate characteris tics of devices based on surface plasmon resonance. In this context, the formation of thin silver films with a low surface roughness is an important problem. To date, there are a number of methods for growing thin silver films on an insulator surface. The most wide spread methods are thermal vacuum evaporation [4], electronbeam evaporation [5, 6], and different tech niques based on sputtering a metal target (magnetron sputtering, ionbeam sputtering, etc.) [7, 8]. In this work we obtained ultrasmooth thin silver films by pulsed laser deposition. Silver films grew on a quartz substrate with predeposited yttrium oxide (Y2O3) buffer layer. This technique allows one to change the energy of adatoms deposited on the sub strate, the substrate temperature, and the gas pressure
in the working chamber in a wide range and thus choose optimal conditions for growing ultrasmooth thin silver films. EXPERIMENTAL Thin silver films were obtained by pulsed laser dep osition. A pulsed excimer Kr
Data Loading...
