Semiconductor for a resistive gas sensor having a high response speed

US4988970A · kind A · utility

Assignee

• Kernforschungszentrum Karlsruhe GmbH · DE

Inventors

• Edelbert Hafele · Karlsruhe, DE
• Karl-Heinz Hardtl · Hagenbach, DE
• Andreas Müller · Wadgassen, DE
• Ulrich Schonauer · Karlsruhe, DE

Key dates

• Filing date: Sep 28, 1989
• Grant date: Jan 29, 1991
• Expiry date: Sep 28, 2009

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N33/0031
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Semiconductors for resistive gas sensors or resistive semiconductor gas sensors with high speed of reaction are disclosed. These semiconductors are appropriate to measure the partial pressure of oxygen and reducing gases in any predetermined measurement range between 10.sup.-30 and about 1 bar or in the whole of this measurement range, their resistance changes being caused by a volume effect. In particular, these semiconductors have a layer less than 100 .mu.m thick, predetermined geometric structure and clearly marked marginal zones. A specially doped semiconductor composed of perowskit having the general formula A'.sub.x A.sub.1-x-Z1 B'.sub.y B.sub.1-y-Z2 O.sub.3 is applied on a substrate with a paste of an organic base material by a thick film technique. By adding or removing at least one element or by using two different semiconductors the characteristic curve is clearly traced.