KR20090059792A - Micro heater, micro heater manufacturing method and environment sensor using thereof - Google Patents

Abstract

A micro heater, a micro heater manufacturing method and an environment sensor using the same are provided to prevent mechanical deformation and deformation due to heat by reducing heat loss and using a silicon oxide film and a silicon nitride film. A micro heater(400) comprises: an elastic film formed by successively evaporates a first silicon oxide film, a silicon nitride film and a second silicon oxide film; a heating part(200), and a diffusing plate(250) and a heating part electrode(210) which are formed on the top of the elastic film; and an insulating film formed on the upper end of the heating part, the diffusing plate and the heating part electrode. The diffusing plate comprises a junction part vertically connected to the heating part.

Description

Micro heater, micro heater manufacturing method and environment sensor using the same

The present invention relates to a micro heating device, a micro heating device manufacturing method and an environmental sensor using the same.

In particular, the present invention relates to a micro heating device with low power consumption and excellent thermal efficiency, and an environmental sensor using the same.

The present invention is derived from a study performed as part of the IT source technology development project of the Ministry of Information and Communication [Task management number: 2006-S-006-02, Task name: ubiquitous terminal components / modules]

As sensor technology develops, research on micro heating devices used in environmental sensors such as gas sensors has also been developed. In particular, the micro heating device is required to have good thermal efficiency at low power and good isothermal property that is uniformly heated throughout the heating device. The diffusion plate of the conventional micro heating device is formed in a wide plate structure, or is diffused in a different layer from the heating part. A method of forming a plate has been used.

However, the diffuser plate having a wide plate structure has a disadvantage of large heat loss and inferior flexibility, and when the diffuser plate and the heating unit exist in different layers, the process becomes complicated and the thermal efficiency is inferior.

Therefore, there is a need for a micro heating device capable of realizing low thermal power and an environmental sensor using the same for an efficient environmental sensor.

An object of the present invention is to provide a micro heating device, a micro heating device manufacturing method, and an environmental sensor using the same.

It is another object of the present invention to provide a micro heating device, a method of manufacturing a micro heating device, and an environmental sensor using the same, which are relatively simple in process and are excellent in thermal efficiency and isothermal characteristics.

In order to achieve the above objects, according to an aspect of the present invention, an elastic thin film in which a first silicon oxide film, a silicon nitride film and a second silicon oxide film are sequentially deposited, a heating part patterned on the elastic thin film, diffusion And an insulating layer formed on top of the plate and the heating electrode, the heating part, the diffusion plate, and the heating electrode, wherein the diffusion plate includes a joint connected to the heating part. Can provide.

In a preferred embodiment, the heating unit, the diffusion plate and the heating electrode may be made of any one of polysilicon, tungsten, aluminum, nickel and platinum. In addition, the heating unit may be formed in a pattern surrounding the diffusion plate. In addition, the diffusion plate may be characterized in that the current does not flow even if the current is applied from the heating unit. In addition, the coupling between the diffusion plate and the heating unit may be characterized in that it has a circuit coupling characteristic of the Wheatstone bridge form. The diffusion plate may include a plurality of concentric circles, and the plurality of concentric circles may be connected by a junction. In addition, the diffusion plate may be characterized by consisting of a plate in the form of a circular disk. In addition, the heating unit may surround the diffusion plate in a gear-shaped pattern and may be vertically connected by the diffusion plate and the junction. In addition, the heating pattern of the heating unit is a micro heating device, characterized in that it can be modified to increase the internal resistance of the heating unit itself.

Referring to another aspect of the present invention, the step of depositing a silicon oxide film, a silicon nitride film and a silicon oxide film on the silicon substrate in order to form an elastic thin film, the heating portion, the diffusion plate and the heating of the conductive material on top of the elastic thin film Forming a sub-electrode, forming an insulating layer on top of the patterned heating part, the diffusion plate, and the heating part electrode, and etching the silicon substrate under the elastic thin film, wherein the diffusion plate is heated. It is possible to provide a method for manufacturing a micro heating device comprising a joint connected vertically to the part.

In a preferred embodiment, when etching the silicon substrate of the lower end of the elastic thin film, all of the insulating layer except for the position of the heating portion, the diffusion plate and the heating electrode formed on the upper end of the elastic thin film, characterized in that the etching can do.

Referring to another aspect of the present invention, a silicon oxide film, a silicon nitride film and a silicon oxide film are deposited in sequence, an elastic thin film, a heating portion, a diffusion plate and a heating electrode electrode formed in a pattern on the elastic thin film, the heating portion And an insulating layer formed on top of the diffusion plate and the heating part electrode, and an environmental sensor electrode and an environmental sensing material formed on the top of the insulating layer, wherein the diffusion plate includes a junction vertically connected to the heating part. An environmental sensor can be provided.

The present invention can provide a micro heating device, a micro heating device manufacturing method, and an environmental sensor using the same.

In addition, the present invention can provide a micro heating device, a micro heating device manufacturing method, and an environmental sensor using the same, the process is relatively simple, and excellent in thermal efficiency and isothermal characteristics.

Hereinafter, a micro heating apparatus, a micro heating apparatus manufacturing method, and an environmental sensor using the same according to the present invention will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the cross section of 1st Example of the micro heating apparatus applied to this invention.

Referring to FIG. 1, the micro heating apparatus 400 according to the present invention includes a silicon substrate 100, a lower silicon oxide thin film 300, a silicon nitride thin film 310, an upper silicon oxide thin film 320, and a heating electrode ( 210, a heating part 200, a diffusion plate 250, and an insulating layer 350.

The micro heating device is a heating device formed through a semiconductor process and serves to change an electrical signal transmitted from the heating unit electrode 210 into thermal energy in the heating unit 200. The diffusion plate 250 connected to the heating unit 200 collects heat generated by the heating unit 200 and serves to even the temperature distribution. Such micro heating devices can be made compact and are used in various sensors or other heating devices.

The silicon substrate 100 is a substrate for forming the micro heating apparatus of the present invention and is generally the same as the silicon substrate which is often used in a semiconductor process. However, since the micro heating apparatus according to the present invention is configured in a thin film form, after all of the micro heating apparatuses are formed on the upper surface of the silicon substrate, the silicon substrate of the portion where the micro heating apparatus is formed is etched and removed 150 from the rear side.

The lower silicon oxide thin film 300, the silicon nitride thin film 310, and the upper silicon oxide thin film 320 are formed of the lower thin film of the micro heating apparatus of the present invention. The reason why the lower thin film is composed of three layers instead of one layer is that when the heating is started in the micro heating apparatus, since the warpage occurs due to the heating, the lower thin film of the micro heating apparatus may be broken or denatured. In order to minimize such denaturation and cracking, a thin film is formed by overlapping a silicon oxide film having a compressive stress and a silicon nitride film having an elongated stress.

The heating part electrode 210 is a part that plays a role of supplying power to the micro heater according to the present invention, and is a conductive wire which transmits electric power applied from the outside to the heating part 200.

Since the heating unit 200 is a circular conductive wire surrounding the diffusion plate 250 and has a smaller resistance value than that of the heating unit electrode 210, heat is generated by Joule's heat. Since the diffusion plate 250 is parallel to the Wheatstone bridge in circuit with the heating unit 200, there is no flow of current to the diffusion plate 250.

The diffusion plate 250 plays a role of collecting the heat energy transferred from the heating unit 200, and is composed of a plurality of concentric circles. In particular, the joint portion that is coupled to the heating portion 200 is vertically bonded to the heating portion 200, and is configured in the same way as the parallel state of the Wheatstone bridge from a circuit point of view. Therefore, the current flowing to the diffusion plate 250 is eliminated and serves to collect only heat without the current of the diffusion plate 250 current.

In particular, the heating part 200, the diffusion plate 250, and the heating part electrode 210 may be made of polysilicon, tungsten, aluminum, nickel, platinum, and the like, which have good thermal conductivity and electrical conductivity and are suitable for use. If it is not metal, it does not matter much.

The insulating layer 350 serves as a protective film to surround all of the heating part 200, the diffusion plate 250, and the heating part electrode 210 to insulate from the outside.

2 is a view showing a plane of a first embodiment of a micro heating device to which the present invention is applied.

Referring to FIG. 2, it can be seen that the micro heating apparatus according to the present invention is formed by etching the silicon substrate described with reference to FIG. 1 in a circular shape at the rear of the micro heating apparatus 400 of the present invention.

It can be seen that the heating unit electrode 210 is a conductive wire connected from the outside of the micro heating device 400, and the heating unit 200 may be a conductive wire formed in a circular shape surrounding the diffusion plate 250 from the outside. The diffusion plate 250 is composed of a plurality of concentric circles, it can be seen that the junction with the heating unit perpendicular to the point where the heating unit 200 is bonded.

By the configuration described above, the diffusion plate 250 serves to collect the heat energy transferred from the heating unit 200, but the current transmitted from the heating unit 200 is not transmitted to the diffusion plate 250 at all.

3 is a view showing a cross section of a second embodiment of a micro heating device to which the present invention is applied.

Referring to FIG. 3, the micro heating apparatus 400 according to the second embodiment of the present invention includes a silicon substrate 100, a lower silicon oxide thin film 300, a silicon nitride thin film 310, an upper silicon oxide thin film 320, The heating part electrode 210, the heating part 200, the diffusion plate 250, the insulating layer 350, and the lower blood is 500.

The micro heating device may play the same role as the micro heating device described with reference to FIG. 1.

The silicon substrate 100 is a substrate for forming the micro heating apparatus of the present invention and is generally the same as the silicon substrate frequently used in a semiconductor process. However, since the micro heating apparatus according to the present invention is configured in a thin film form, after all the micro heating apparatus is formed on the upper surface of the silicon substrate, the micro heating apparatus (see FIG. 1) is different from the method described in FIG. The lower lower silicon oxide thin film 300, the lower silicon nitride thin film 310, the upper silicon oxide thin film 320, and the silicon substrate 100 are etched to form the lower bleeding blood 500, except for the portion 400.

When the lower bleeding blood 500 is configured, the micro heating device 400 is actually etched except for the portion in which the heating electrode 210, the heating part 200, and the diffusion plate 250 are formed, unlike in FIG. 1. Connected with the blood 500, the micro heating device is formed in a shape in which the heating unit 200 and the diffusion plate 250 around the hollow.

4 is a view showing a plane of a second embodiment of a micro heating device to which the present invention is applied.

Referring to FIG. 4, the micro heating apparatus according to the second exemplary embodiment of the present invention is etched in the silicon substrate described in FIG. 3 except for the part of the micro heating apparatus 400 of the present invention.

As can be seen in the figure, except for the portion of the micro heating device 400, all of the surroundings are etched to form a lower blood vessel 500. Such etching can be etched using microfabrication techniques. In the case of manufacturing the micro heating apparatus 400 in this manner, since it is not necessary to etch the silicon from the rear side, the microcavity technique is used on the front side so as to produce the lower bleeding blood 500 by etching the unnecessary parts. May exist.

FIG. 5 is a diagram showing the results of simulation of prediction of a micro heating device applied to the present invention. FIG.

It is a figure which shows the temperature change distribution of the micro heating apparatus applied to this invention.

5a simulated using a finite element analysis method, the applied power was used 25mW, the diffusion plate was used platinum (Pt). In this case, the maximum temperature of the heating unit 200 was predicted as 713.01K as can be seen in the figure. This shows 440 degrees Celsius, so it can be seen that the micro heating device exhibits sufficient performance. In addition, as can be seen in this figure, it can be seen that the isothermal characteristic of the entire diffusion plate is also sufficiently satisfied.

5B is a diagram showing the current flow in the micro heating device applied to the present invention.

Since the diffusion plate of the present invention serves as a Wheatstone bridge in terms of circuits, the current flowing from the outside does not flow at all, and it is described in the preceding drawings, and the result of the simulation is shown in FIG. 5B.

As can be seen in the drawing of FIG. 5B, it can be seen that the current flowing through the heating unit electrode and the heating unit does not flow to the diffusion plate at all.

6 is a view showing an embodiment of an environmental sensor according to the present invention.

FIG. 6A is a cross-sectional view of a gas sensing device configured by adding a gas sensing electrode 270 and a gas sensing material 600 to an upper end of a micro heating apparatus according to the first embodiment described with reference to FIG. 1. 6B is a cross-sectional view of the gas sensing device configured by adding the gas sensing electrode 270 and the gas sensing material 600 to the top of the micro heating apparatus according to the second embodiment described with reference to FIG. 3.

7 is a view showing an embodiment of the heating unit and the diffusion plate in the micro heating apparatus applied to the present invention.

FIG. 7A is a view of the heating unit 200 and the diffusion plate 250 of the first and second embodiments described with reference to FIGS. 2 and 4 of the present invention. The heating unit 200 has a concentric circle structure, and the diffusion plate 250 is connected to the heating unit 200 by a Wheatstone bridge. The diffusion plate 250 has a shape in which a plurality of concentric circles are connected. Heat energy generated by the heating unit 200 is collected by the diffusion plate 250 and a uniform heat distribution is formed.

FIG. 7B is a view of another type of diffuser plate 250. The diffusion plate 250 is in the form of a circular disk rather than a plurality of concentric circles. In the case of using the diffusion plate 250 having such a structure, there is no need to etch another pattern on the diffusion plate, thereby simplifying the manufacturing process.

FIG. 7C is a view illustrating another type of heating unit 200. The heating unit 200 is a curved shape rather than a concentric structure. Such a curved shape can increase the electrical resistance of the concentric structure. The resistance characteristics vary depending on the shape of the heating part, and the bending pattern does not need to be the shape illustrated in this drawing, and may be configured by any number of deformations in the form of increasing the resistance component. In other words, the resistance component can be made large in the form of longer length or reduced cross-sectional area.

Thus, when the gas sensing device is configured using the micro heating device according to the present invention, heat loss is less than that of the conventional micro heating device. Degeneration can be significantly stronger.

In addition to the gas detection device described in the above drawings, when the micro heating device of the present invention is applied to many parts of the environmental sensor to which the micro heating device is applied, a more efficient environmental sensor can be configured.

The present invention is not limited to the above embodiments, and many variations are possible by those skilled in the art within the spirit of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which shows the cross section of the 1st Example of the micro heating apparatus applied to this invention.

2 is a view showing a plane of a first embodiment of a micro heating device to which the present invention is applied;

3 is a cross-sectional view of a second embodiment of a micro heating device applied to the present invention.

4 is a view showing a plane of a second embodiment of a micro heating device to which the present invention is applied;

5 is a diagram showing the results of simulation of prediction of a micro heating device applied to the present invention.

6 shows an embodiment of an environmental sensor according to the invention;

7 is a view showing an embodiment of a heating unit and a diffusion plate in the micro heating apparatus applied to the present invention.

<Explanation of symbols for the main parts of the drawings>

400: micro heating device 100: silicon substrate

300: lower silicon oxide thin film 310: silicon nitride thin film

320: upper silicon oxide thin film 210: heating part electrode

200: heating part 250: diffusion plate

350: insulation layer

Claims (12)

An elastic thin film in which a first silicon oxide film, a silicon nitride film, and a second silicon oxide film are sequentially deposited; A heating part, a diffusion plate, and a heating part electrode formed in a pattern on the elastic thin film; An insulating layer formed on top of the heating part, the diffusion plate, and the heating part electrode To include, wherein the diffusion plate comprises a junction vertically connected with the heating portion Micro heating device, characterized in that. The method of claim 1, And the heating part, the diffusion plate, and the heating part electrode are made of any one of polysilicon, tungsten, aluminum, nickel, and platinum. The method of claim 1, The heating unit is a micro heating device, characterized in that formed in a pattern surrounding the diffusion plate. The method of claim 1, The diffusion plate is a micro heating device, characterized in that no current flows even if the current is applied from the heating unit. The method of claim 4, wherein The coupling of the diffusion plate and the heating unit is a micro heating device, characterized in that it has a circuit coupling characteristic of the Wheatstone bridge form. The method of claim 1, The diffusion plate includes a plurality of concentric circles, the plurality of concentric circles are micro heating apparatus, characterized in that connected by the respective concentric circles and the junction. The method of claim 1, The diffusion plate is a micro heating device, characterized in that consisting of a circular disk-shaped plate. The method of claim 1, The heating unit surrounds the diffusion plate in a gear-shaped pattern, and the micro heating device, characterized in that connected vertically by the diffusion plate and the junction. The method of claim 8, Micro heating apparatus, characterized in that the pattern form of the heating unit can be modified to increase the internal resistance of the heating unit itself. Depositing a first silicon oxide film, a silicon nitride film, and a second silicon oxide film on a silicon substrate in order to form an elastic thin film; Patterning a heating part, a diffusion plate, and a heating part electrode of a conductive material on an upper end of the elastic thin film; Forming an insulating layer on top of the patterned heating part, the diffusion plate, and the heating part electrode; and Etching the silicon substrate under the elastic thin film Including but the diffusion plate comprises a junction vertically connected with the heating portion Micro heating device manufacturing method characterized in that. The method of claim 10, When etching the silicon substrate at the bottom of the elastic thin film, all except the position of the heating portion, the diffusion plate and the heating electrode formed on the top of the elastic thin film to the insulating layer, characterized in that the manufacturing method of the micro heating device. . An elastic thin film in which a silicon oxide film, a silicon nitride film, and a silicon oxide film are sequentially deposited; A heating part, a diffusion plate, and a heating part electrode formed on a pattern of the elastic thin film; An insulating layer formed on top of the heating part, the diffusion plate, and the heating part electrode; Environmental sensor electrode and environmental sensing material formed on the top of the insulating layer To include, wherein the diffusion plate comprises a junction vertically connected with the heating portion Environmental sensor characterized in that.

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