Microfabrication and reliability study of sapphire-based Ti/Pt electrodes for thin film gas sensor applications

Wenmin Qu; Wojtek Wlodarski; Michael W. Austin

doi:10.1117/12.364486

1 October 1999 Microfabrication and reliability study of sapphire-based Ti/Pt electrodes for thin film gas sensor applications

Wenmin Qu, Wojtek Wlodarski, Michael W. Austin

Author Affiliations +

Proceedings Volume 3892, Device and Process Technologies for MEMS and Microelectronics; (1999) https://doi.org/10.1117/12.364486
Event: Asia Pacific Symposium on Microelectronics and MEMS, 1999, Gold Coast, Australia

Abstract

The paper describes design, fabrication and characterization of a Ti/Pt electrode system, on a sapphire substrate. It serves as substrates for subsequent deposition of gas sensitive films. The fabrication has been accomplished on both sides of a sapphire wafer. Wet chemical etching and the lift-off method have respectively been used for structuring the electrode and the heater patterns. The mechanical stability and the electrical conductivity of the resultant Ti/Pt films are greatly affected by the subsequent heat treatment procedures. The diffusion of titanium ions into platinum has been examined using SIMS depth profiles. After annealing at 600 degrees C for 5 hours, the temperature coefficient of the Ti/Pt film stabilized on the value 0.0033 K^-1, which approaches the pure platinum bulk value of 0.0039 K^-1. With a good mechanical and thermodynamical stability at high temperatures and under oxidizing and reducing conditions, the sapphire based Ti/Pt electrode system is well suited for gas sensor fabrication. As an example of its application, we report a highly sensitive O₃ gas sensor developed by evaporating a WO₃ thin-film onto this electrode.

Citation Download Citation

Wenmin Qu, Wojtek Wlodarski, and Michael W. Austin "Microfabrication and reliability study of sapphire-based Ti/Pt electrodes for thin film gas sensor applications", Proc. SPIE 3892, Device and Process Technologies for MEMS and Microelectronics, (1 October 1999); https://doi.org/10.1117/12.364486

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
9 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Electrodes

Sapphire

Platinum

Thin films

Gas sensors

Sensors

Titanium

Show All Keywords

Keywords/Phrases

Search In:

Publication Years