Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Sensor for detecting gas and its producing method

A technology for detecting gases and sensors, applied in the direction of material resistance, etc., can solve the problems of complex device manufacturing process, inaccurate detection, low sensitivity, etc., and achieve the effects of rapid response and recovery, simple process, and high sensitivity

Inactive Publication Date: 2004-02-11
INST OF PHYSICS - CHINESE ACAD OF SCI
View PDF0 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to: overcome the shortcomings of existing gas sensors with low sensitivity and poor selectivity, which cause inaccurate detection; in addition, overcome the existing device with a multi-layer film structure, which makes the device manufacturing process complicated and costly. High disadvantage; thereby providing a sensor with high selectivity, high sensitivity and fast response and recovery performance for detecting gas and its manufacturing method

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Sensor for detecting gas and its producing method
  • Sensor for detecting gas and its producing method
  • Sensor for detecting gas and its producing method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] The specific structure of the sensor of the present invention can be found in figure 2 and image 3 , a polished single crystal silicon wafer is used as the substrate 1, and a layer of 0.5 μm thick diamond film / nano-diamond film 6 is grown on one side of the substrate 1; Au electrode 4, its Ti is thick 50 or 200nm, the composite metal electrode of Pt thick 100 or 400nm and Au thick 200 or 600nm; Its width is 3 or 7mm, and length is consistent with substrate width; 2 Au wire measuring leads 5 are connected in on electrode 4. A comb-shaped Pt heating resistor 2 is made on the back side of the substrate 1, and a Pt metal film with a thickness of 500-1000 nm is used to etch the metal film into Pt metal strips with a width of 10 or 50 μm. It is 15mm×15mm, and the resistance value is 0.1-5Ω; the heating resistor lead 3 made of gold is connected to the two ends of the heating resistor 2 .

Embodiment 2

[0035] The specific structure of the sensor in this embodiment can be found in figure 2 and image 3 , and in conjunction with the manufacturing method, the specific structure of the sensor of the present invention is described in detail:

[0036] (1) Make a substrate 1 on a polished single-crystal silicon wafer, vapor-deposit a 700nm metal film on its back side by sputtering, and use photolithography to etch the metal film into a Ti metal strip with a width of 25 μm. Comb-shaped heating resistor 2, two gold wires as the lead wire 3 of the heating resistor are connected to both ends of the heating resistor 2. The heating resistor 2 is designed on the one hand to make the diamond film recover as soon as possible at high temperature (300-400°C) after absorbing gas, and improve the recovery time; on the other hand, it is to improve the response time of the diamond film to gas adsorption at high temperature.

[0037] (2) After the electrode is made, make a diamond film / nano-dia...

Embodiment 3

[0041] The substrate 1 is made of a polished single-crystal silicon wafer, which also includes depositing 200-600nm silicon dioxide as an insulating layer on the substrate 1 by using a low-pressure CVD method, in order to improve measurement accuracy. All the other structures are the same as in Example 1, and the preparation method also includes the following annealing steps: placing the grown diamond film in H 2 Or annealing in H plasma: the annealing conditions are as follows: substrate temperature: 600-1000°C, H 2 Flow rate: 100-1000sccm, gas pressure: 5-60mbar, annealing time: 20 minutes-2 hours. All the other processes are the same as in Example 2. The diamond film is prepared by hot filament chemical vapor deposition (HFCVD). The diamond film containing micron / submicron crystal grains is formed on the substrate by traditional grinding or bias nucleation, using methane and hydrogen to react at high temperature. Synthetic. The nanodiamond film was prepared under DC nega...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
electrical resistanceaaaaaaaaaa
widthaaaaaaaaaa
Login to View More

Abstract

The gas detecting sensor includes substrate, one layer of diamond film / nano diamond film on one side of the substrate, two metal electrodes connected to the diamond film / nano diamond film and leads; heating resistor on the other side with measuring leads connected to ends. The making process includes making heating resistor, pressure welding measuring leads to ends of the heating resistor; hot wire chemical vapor deposition to prepare diamond, forming nano diamond film via grinding or bias nucleating on the substrate via high temperature reaction of methane or hydrogen; and leading out the metal electrodes. The sensor has high selectivity, high sensitivity, fast response, excellent restore homogeneity, high temperature resistance, high radiation resistance and simple production process.

Description

technical field [0001] The invention belongs to a gas sensor, in particular to a sensor including a diamond film / nanometer diamond film for detecting gas and a manufacturing method thereof. Background technique [0002] The gas sensor made in the prior art is a metal-insulator-semiconductor (MIS) diode structure using a traditional catalytic metal electrode. The difference is that the intrinsic diamond film is used as the insulating layer, and the doped diamond film is used as the semiconductor layer. Sensitive film or conventional SnO x Sensitive materials, catalytic electrodes are traditional Pt. Generally, depending on the sensitive membrane and the catalytic electrode, the H 2 , O 2 , CO and other gas detection. Such as document 1: "High-temperature tolerant diamond diode for carbon monoxide gas detection for CO gas detection", published in "Journal of Applied Physics" 1998, Vol.84, No.7: 6935-6936 ; This kind of gas sensor using diamond film as insulation and semic...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G01N27/04G01N27/16
Inventor 顾长志贾继奎刘维窦艳
Owner INST OF PHYSICS - CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com