Developing GLAD Parameters to Control the Deposition of Nanostructured Thin Film

In this paper, we describe the device developed to control the deposition parameters to manage the glancing angle deposition (GLAD) process of metal-oxide thin films for gas-sensing applications. The GLAD technique is based on a set of parameters such as the tilt, rotation, and substrate temperature. All parameters are crucial to control the deposition of nanostructured thin films. Therefore, the developed GLAD controller enables the control of all parameters by the scientist during the deposition. Additionally, commercially available vacuum components were used, including a three-axis manipulator. High-precision readings were tested, where the relative errors calculated using the parameters provided by the manufacturer were 1.5% and 1.9% for left and right directions, respectively. However, thanks to the formula developed by our team, the values were decreased to 0.8% and 0.69%, respectively.

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Surface Functionalization of Porous Nanostructured Metal Oxide Thin Films Fabricated by Glancing Angle Deposition

Chemistry of Materials ◽

10.1021/cm061709t ◽

2006 ◽

Vol 18 (22) ◽

pp. 5260-5266 ◽

Cited By ~ 29

Author(s):

Shufen Tsoi ◽

Enrico Fok ◽

Jeremy C. Sit ◽

Jonathan G. C. Veinot

Keyword(s):

Thin Films ◽

Metal Oxide ◽

Surface Functionalization ◽

Glancing Angle Deposition ◽

Oxide Thin Films ◽

Metal Oxide Thin Films ◽

Glancing Angle ◽

Angle Deposition ◽

Nanostructured Metal

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Various methods used to etch titanium dioxide columnar thin films

MRS Proceedings ◽

10.1557/proc-1174-v10-04 ◽

2009 ◽

Vol 1174 ◽

Author(s):

Martin Roman Kupsta ◽

Mike Taschuk ◽

Michael J. Brett ◽

Jeremy C. Sit

Keyword(s):

Thin Films ◽

Titanium Dioxide ◽

Glancing Angle Deposition ◽

Ion Etching ◽

Sensing Applications ◽

Glancing Angle ◽

Wet Chemical ◽

Dry Etch ◽

Anisotropic Etch ◽

Angle Deposition

AbstractA dry etch recipe was developed for porous nanostructured TiO2 thin films fabricated using glancing angle deposition (GLAD). Unlike wet chemical etches, the technique reported here preserves the vertical post nanostructure, eliminating clumping. A highly controllable and easily tailored reactive ion etching process with CF4 alone, or combined with O2, was investigated. The anisotropic etch modifies the morphology and density of standard GLAD films, which is of interest for sensing applications.

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Fabrication of Perforated Film Nanostructures

MRS Proceedings ◽

10.1557/proc-739-h8.5 ◽

2002 ◽

Vol 739 ◽

Author(s):

A. L. Elias ◽

K. D. Harris ◽

M. J. Brett

Keyword(s):

Thin Films ◽

Glancing Angle Deposition ◽

Thin Coatings ◽

Glancing Angle ◽

Perforated Film ◽

Glad Technique ◽

Angle Deposition

ABSTRACTWe have demonstrated the fabrication of perforated thin films (PTFs), comprised of thin coatings perforated with unusual pore shapes such as helices or chevrons. PTFs are fabricated using a template of nanohelices or nanochevrons produced using the Glancing Angle Deposition (GLAD) technique. PTFs can be produced by filling GLAD films with a variety of substances, etching back the coating to reveal the tips of the helices or chevrons, and etching out the template film. A process for fabricating nickel PTFs has been developed, and a nickel PTF of helical pores with nominal diameters of 100nm has been produced.

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Near surface characteristics of highly sensitive metal oxide thin films

MRS Proceedings ◽

10.1557/proc-828-a1.5 ◽

2004 ◽

Vol 828 ◽

Author(s):

G. Kiriakidis

Keyword(s):

Thin Films ◽

Secondary Ion Mass Spectrometry ◽

Gas Sensing ◽

High Sensitivity ◽

Surface Characteristics ◽

Metal Oxide Thin Films ◽

Near Surface ◽

Dc Sputtering ◽

Deposition Parameters ◽

Temperature And Growth

ABSTRACTWe present the gas sensing properties of InOx thin films deposited by dc sputtering and ZnOx thin films deposited both by dc sputtering and PLD. The sensitivity of the films towards ozone is correlated with the deposition parameters like film thickness, substrate deposition temperature and growth rate. Secondary Ion Mass Spectrometry (SIMS) analysis showed a noticeable deficit in oxygen in the top 5 nm for films in the “conducting” state, i.e., after UV exposure. Analysis of the sensing response for alumina-based transducers of InOx thin films revealed high sensitivity (less than 25 ppb) with fast and stable response towards ozone while ultimate sensitivity levels down to 10 ppb for ozone and 50 ppb for NO2 were achieved. Surface topography study of ZnOx films utilizing optical, AFM and SEM analyses has shown a distinct surface morphology variation correlated to the growth technique It is demonstrated that PLD leads to very rough surfaces with characteristic non-coordinated columnar features in contrast with the rather smooth surfaces obtained by sputtering.

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Fabrication and Ethanol Sensing Characterization of Tin Oxide Nanorods Prepared by Glancing Angle Deposition Technique

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.675-676.163 ◽

2016 ◽

Vol 675-676 ◽

pp. 163-166 ◽

Cited By ~ 1

Author(s):

Chaiyan Oros ◽

Anurat Wisitsoraat ◽

Mati Horprathum

Keyword(s):

Crystal Structure ◽

Thin Films ◽

Flow Rate ◽

Tin Oxide ◽

Gas Sensing ◽

Glancing Angle Deposition ◽

Flow Rates ◽

Glancing Angle ◽

Ethanol Sensing ◽

Angle Deposition

In this work, the nanorod structure of Tin oxide (SnO2) prepared by glancing angle deposition (GLAD) technique with different O2 flow rate from 12 to 48 sccm. The surface and Crystal structure of SnO2 thin films were characterized by scanning electron microscopy (SEM), X-raydiffraction (XRD) and tested toward ethanol gas sensing. Structural characterization showed that the morphological of all SnO2 thin films prepared with different O2 flow rates consists of columnar nanorod structures and the nanorod size which are likely to decrease as the O2 flow rate increases. As the O2 flow rate increases from 12 to 48 sccm, the crystal structure of SnO2 nanorods changes from amorphous to crystalline and the crystallinity is improved by the increase of the O2 flow rate. Gas sensing performances of SnO2 nanorods have been characterized toward ethanol sensing. It was found that SnO2 nanorods exhibit n-type conductivity with decreased resistance when exposed to ethanol, which is reducing gas. In addition, sensitivity to ethanol tend to improve as O2 flow rate increases. Furthermore, the SnO2 nanorods prepared at O2 flow rates 48 sccm are detecting ethanol gas at concentrations lower than 50 ppm at operating temperature 250 °C.

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Thin films with nanometer-scale pillar microstructure

Journal of Materials Research ◽

10.1557/jmr.1999.0423 ◽

1999 ◽

Vol 14 (7) ◽

pp. 3158-3163 ◽

Cited By ~ 65

Author(s):

K. Robbie ◽

C. Shafai ◽

M. J. Brett

Keyword(s):

Thin Films ◽

Incident Angle ◽

High Surface ◽

High Surface Area ◽

Glancing Angle Deposition ◽

Vapor Flux ◽

Substrate Rotation ◽

Glancing Angle ◽

Glad Technique ◽

Columnar Thin Film

Thin films possessing microstructure composed of isolated vertical pillars were deposited by glancing angle deposition (GLAD) without the need for subsequent etch processing. The GLAD technique uses substrate rotation and oblique angle flux incidence to deposit a porous columnar thin film with engineered microstructures. Thin films with a pillar microstructure were fabricated from a variety of metals, metal oxides and fluorides, and semiconductors. The rate and incident angle of vapor flux, as well as the substrate rotation speed during deposition, were found to critically affect pillar microstructure. Thin films with pillar diameters and densities as low as 30 nm and 3 pillars per μm2, respectively, were deposited. The low stress, high surface area, and porous nature of these films suggests use of pillar microstructure films in optical, chemical, biological, mechanical, magnetic, and electrical applications.

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