A reactive laser ablation source for the production of thin films

Abstract

A discription of a thin film deposition source which is based upon the “Smalley metal cluster source” is presented. Our laser assisted molecular beam deposition source incorporates four major innovations: (1) placing the source so it sits external to the deposition chamber, (2) positioning the ablation target at an angle greater than 90° with respect to the laser entrance window, (3) placing the laser entrance window/lens further from the ablation target, and (4) the addition of a second optical window for laser alignment and in situ spectral analysis of the laser ablation plume. Novel molecules can be generated in this source through use of a reactive carrier gas. For example, employing a Ti target rod and O2 carrier gas; flat, uniform micron thick thin films of TiO2 can be easily generated.

Fabrication of anatase-type TiO2 films by reactive pulsed laser deposition for photocatalyst application

“…In addition, TiO 2 film is expected to be used as electrodes for solar power generation (Nakamara et al, 2005). There are many methods to obtain TiO 2 films, such as sol-gel (Tada and Honda, 1995), DC magnetron sputtering (Pamu et al, 2005), RF sputtering (Deloach et al, 1999), and pulsed laser deposition (PLD) (Luca, 2005;Hsieh et al, 2002;György et al, 2005;Syarif et al, 2002;Yoshida et al, 2005;Shinohara et al, 2002;Inoue et al, 2002;Sharma et al, 2003;Ohshima et al, 2006;Kim et 1999; Rexer et al, 1998;Kitazawa et al, 2004;Kitazawa, 2004;Yamaki et al, 2002;Yamamoto et al, 2001;ITO et al, 2004;Okubo et al, 2002;Choi et al, 2004;Suda et al, 2005Suda et al, , 2004. Due to its excellent flexibility of deposition conditions, PLD shows high potential for producing TiO 2 films having rough surfaces (Chrisey and Hubler, 1994a).…”

“…An effective way to fabricate anatase TiO 2 films is using a metallic Ti target in O 2 atmosphere under a temperature below 700 • C (Rexer et al, 1998). In this method, TiO 2 film is synthesized via the chemical reaction between the ejected species ablated from the Ti target and the ambient O 2 gas.…”

Preparation of Zinc Oxide Thin Films by Reactive Pulsed Arc Molecular Beam Deposition

“…[20][21][22] This technique utilizes a pulsed 248 nm ultraviolet excimer laser beam for ablating the material of interest to create a hightemperature plasma. A reactive gas is then expended from a molecular beam nozzle to react with the ablated material and also to act as a carrier gas to move the product to be deposited to the substrate.…”

“…In our previous work, laser-assisted molecular beam deposition (LAMBD), a thin film deposition system, has demonstrated its unique ability to produce high-quality thin films by combining laser ablation and a molecular beam expansion. − This technique utilizes a pulsed 248 nm ultraviolet excimer laser beam for ablating the material of interest to create a high-temperature plasma. A reactive gas is then expended from a molecular beam nozzle to react with the ablated material and also to act as a carrier gas to move the product to be deposited to the substrate.…”