Search for content and authors
 

Thin films of pure and Pt or Ru doped Al2O3 as catalytic membranes for selective semiconductor gas sensors

Andrey Ryzhikov 1,2Michel Labeau 2Alexander M. Gaskov 1

1. M.V. Lomonosov Moscow State University, Vorobyevy gory, Moscow 119992, Russian Federation
2. INPG, Laboratoire des Materiaux et du Genie Physique (LMGP), BP 46, Grenoble 38402, France

Abstract

Semiconductor gas sensor stability and selectivity can be improved by using catalytic filtering membranes to avoid interference of various gas molecules. The deposition of dielectric thin films doped with catalytic metals directly on the surface of semiconductor sensing element allows to increase the selectivity without considerable decrease of the sensitivity and increase of the response time.
The films were obtained by aerosol pyrolysis method. The filtering membranes of pure and Pt or Ru doped Al2O3 with various thickness (6-160 nm) were deposited on the surface of SnO2(Pd) films. Phase composition and microstructure of the films were studied by X-ray diffraction, Atomic Force Microscopy, Transmission Electron Microscopy and Electron Probe MicroAnalysis.
Sensors properties of SnO2(Pd)/Al2O3 and SnO2(Pd)/Al2O3(Me) structures (Me = Pt, Ru) were studied under H2, CH4, C3H8 and CO-air gas mixtures in a temperature range 100-300C. The use of the membranes increases the response time of the sensors. All membranes reduce significantly the sensitivity to CO in the temperature range and increase the sensitivity to CH4 and C3H8 at 200C. Ru-doped membranes significantly reduce the sensitivity to H2. Sensitivity and response time considerably depend on membrane thickness.

 

Legal notice
  • Legal notice:
 

Related papers

Presentation: poster at E-MRS Fall Meeting 2004, Symposium A, by Andrey S. RYZHIKOV
See On-line Journal of E-MRS Fall Meeting 2004

Submitted: 2004-04-30 18:15
Revised:   2009-06-08 12:55