NANO-CRYSTALLINE COMPOSITE-OXIDE THIN FILM, ENVIRONMENTAL GAS SENSOR USING THE THIN FILM, AND METHOD OF MANUFACTURING THE ENVIRONMENTAL GAS SENSOR

• US 20090148347A1
• Filed: 08/13/2008
• Published: 06/11/2009
• Est. Priority Date: 12/10/2007
• Status: Abandoned Application

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Zyung, Tae Hyoung, Park, Jin Ah, LEE, Su Jae, Moon, Jae Hyun
• Application Number:
  US12/190,991
• Publication Number:
  US 20090148347A1
• Time in Patent Office: Days
• US Class Current: 422/83
• CPC Class Codes: C04B 2235/3251 Niobium oxides, niobates, tantalum oxides, tantalates, or oxide-forming salts thereof
• CPC Class Codes: C04B 35/4682 based on BaTiO3 perovskite phase
• CPC Class Codes: C23C 14/08 Oxides C23C14/10 takes precedence
• CPC Class Codes: G01N 27/125 Composition of the body, e.g. the composition of its sensitive layer

Abstract

A nano-crystalline composite-oxide thin film for an environmental gas sensor, an environmental gas sensor using the thin film, and a method of manufacturing the environmental gas sensor are provided. The nano-crystalline composite-oxide thin film is formed of hetero-oxide nano-crystalline particles having independent crystalline phases from each other, and the environmental gas sensor including the thin film has excellent characteristics including high sensitivity, high selectivity, high stability and low power consumption.

Claims

1. A nano-crystalline composite-oxide thin film for an environmental gas sensor, which is formed of hetero-oxide nano-crystalline particles having independent crystalline phases from each other.

2. The thin film according to claim 1, wherein the oxide includes at least two selected from the group consisting of ABO₃-type perovskite oxides (BaTiO₃, metal-doped BaTiO₃, SrTiO₃ and BaSnO₃), ZnO, CuO, NiO, SnO₂, TiO₂, CoO, In₂O₃, WO₃, MgO, CaO, La₂O₃, Nd₂O₃, Y₂O₃, CeO₂, PbO, ZrO₂, Fe₂O₃, Bi₂O₃, V₂O₅, VO₂, Nb₂O₅, Co₃O₄ and Al₂O₃.

3. The thin film according to claim 1, wherein the hetero-oxide nano-crystalline particles have diameters ranging from 1 to 100 nm.

4. An environmental gas sensor, comprising:

a substrate;

a metal electrode formed on the substrate; and

a composite-oxide thin film formed of hetero-oxide nano-crystalline particles on the metal electrode.

5. The sensor according to claim 4, wherein the substrate is one selected from the group consisting of oxide single crystalline and ceramic substrates (MgO, LaA₂O₃ and Al₂O₃), a silicon semiconductor substrate (Si and SiO₂) and a glass substrate.

6. The sensor according to claim 4, wherein the substrate is formed to a thickness of 0.1 to 1 mm

7. The sensor according to claim 4, wherein the metal electrode includes at least one selected from the group consisting of platinum (Pt), gold (Au), silver (Ag), aluminum (Al), nickel (Ni), titanium (Ti), copper (Cu) and chromium (Cr).

8. The sensor according to claim 4, wherein the nano-crystalline composite-oxide thin film is formed of hetero-oxide nano-crystalline particles having independent crystalline phases from each other, and the oxide includes at least two selected from the group consisting of ABO₃-type perovskite oxides (BaTiO₃, metal-doped BaTiO₃, SrTiO₃ and BaSnO₃), ZnO, CuO, NiO, SnO₂, TiO₂, CoO, In₂O₃, WO₃, MgO, CaO, La₂O₃, Nd₂O₃, Y₂O₃, CeO₂, PbO, ZrO₂, Fe₂O₃, Bi₂O₃, V₂O₅, VO₂, Nb₂O₅, Co₃O₄ and Al₂O₃.

9. The sensor according to claim 4, wherein the nano-crystalline composite-oxide thin film is formed to a thickness of 1 to 1000 nm.

10. A method of manufacturing an environmental gas sensor, comprising:

forming a metal electrode on a substrate; and

growing hetero-oxide nano-crystalline particles on the metal electrode and forming a nano-crystalline composite-oxide thin film.

11. The method according to claim 10, wherein the growing of the hetero-oxide nano-crystalline particles is performed by sputtering or pulsed laser deposition using a hetero-oxide ceramic target.

12. The method according to claim 10, wherein the growing of the hetero-oxide nano-crystalline particles is performed by pulsed laser deposition having a dual laser beam using two oxide ceramic targets.

13. The method according to claim 10, wherein the nano-crystalline composite-oxide thin film is deposited at a temperature ranging from room temperature to 800°

C.