KR101827137B1 - Method of manufacturing an ultra-violet sensor - Google Patents

Abstract

The present invention relates to a method for manufacturing an infrared sensor. The method for manufacturing an infrared sensor comprises: forming a porous insulating layer on a base substrate; and an infrared sensing part detecting infrared rays on the porous insulation layer, wherein the porous insulating layer is formed through a sol-gel process using an oxide solvent containing a surfactant. Therefore, an infrared sensor can be manufactured through a simple process.

Description

METHOD OF MANUFACTURING AN ULTRA-VIOLET SENSOR < RTI ID = 0.0 >

The present invention relates to a method of manufacturing an infrared sensor, and more particularly, to a method of manufacturing an infrared sensor capable of easily forming a heat insulating layer having a plurality of pores.

A resistive type bolometer is used as a typical infrared ray detection sensor of an infrared image detecting apparatus. The resistance type bolometer is driven by the principle of detecting infrared rays through electrical change of the sensor material when the infrared ray is incident. The resistive-type BLOMETER has a better sensitivity and response than other infrared-ray detection sensors, and is easily used for an infrared image detecting apparatus because of its small size.

It is important to minimize the thermal loss of the sensing part in order to obtain excellent sensing characteristics in the production of infrared sensors. Accordingly, a vacuum having a thermal conductivity close to zero is most effective. Therefore, in the case of the conventional infrared sensor, the sensor has an air cavity structure for forming a vacuum in the lower part of the sensing layer. In order to form such a structure, a sacrificial layer (a temporary layer for forming a vacuum layer) is formed between the device and the substrate by using a micro electro mechanical system (MEMS) technique, and a sacrificial layer Thereby forming an air cavity structure at the bottom of the device. As a result, it is possible to thermally isolate the sensing unit by making the sensing unit have a three-dimensional structure floating in the air. In order to fabricate such an infrared sensor having a three-dimensional structure, the MEMS technology must be applied, thereby increasing the complexity of the process and reducing the production yield of the device. Furthermore, there is a disadvantage that the durability of the device due to the air cavity structure at the lower part of the device, the production unit cost, and the reliability of the device are greatly deteriorated.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a method of manufacturing an infrared sensor which can be manufactured by a simple process while having a simplified structure.

According to another aspect of the present invention, there is provided a method of manufacturing an infrared sensor, including forming a porous insulating layer on a base substrate and forming an infrared sensor on the porous insulating layer to detect infrared rays. Here, the porous insulating layer is formed through a sol-gel process using an oxide solvent containing a surfactant.

In one embodiment of the present invention, the sol-gel process may utilize a spin coating process.

In one embodiment of the present invention, the oxide solvent may include silicon oxide.

In one embodiment of the present invention, the porosity of the porous heat insulating layer can be controlled by controlling the concentration of the surfactant.

In one embodiment of the present invention, the porous insulating layer may have a porosity ranging from 40 to 70%.

In one embodiment of the present invention, the infrared sensing unit forms a sensing layer and electrodes on the porous insulating layer, and forms an insulating layer on the porous insulating layer so as to cover the sensing layer and the electrodes. Then, an absorbing layer and a protective layer are sequentially formed on the insulating layer.

Here, the sensing layer or the protective layer may have a porous structure.

In one embodiment of the present invention, the sensing layer may be formed using lanthanum strontium manganese oxide.

According to the manufacturing method of the infrared sensor according to the embodiments of the present invention, the porous insulating layer is formed through the sol-gel process, so that it can be formed through a simpler process than the conventional anodizing or PECVD.

Further, as compared with the conventional infrared sensor having the conventional vacuum air cavity structure, the infrared sensor manufactured according to the embodiment of the present invention has a planar two-dimensional structure, and the distance between the infrared sensor and the electrodes is reduced It is possible to improve the response characteristic and minimize the size of the infrared sensor. As a result, the infrared sensor can be miniaturized and the integration degree can be improved.

Since the infrared sensor manufactured according to the manufacturing method of the present invention has a two-dimensional planar structure, an infrared sensor can be manufactured by applying a simple manufacturing process. Furthermore, the infrared sensor has better durability than a three-dimensional air cavity structure.

1 to 5 are views for explaining a method of manufacturing an infrared sensor according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. In the accompanying drawings, the sizes and the quantities of objects are shown enlarged or reduced from the actual size for the sake of clarity of the present invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprise", "comprising", and the like are intended to specify that there is a feature, step, function, element, or combination of features disclosed in the specification, Quot; or " an " or < / RTI > combinations thereof.

On the other hand, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

  1 to 5 are views for explaining a method of manufacturing an infrared sensor according to an embodiment of the present invention.

Referring to FIG. 1, an insulating layer 2 is formed on a base substrate 1 according to an embodiment of the present invention. The insulating film 2 may be made of silicon oxide or silicon nitride. Thus, the insulating layer 2 electrically insulates the electrodes and the sensing layer, which will be formed subsequently, from the substrate.

A reflection pattern 6 may be formed on the insulating layer 2. [ The ultraviolet rays incident toward the reflection pattern 6 are reflected toward the upper sensing layer, thereby ensuring an excellent detection efficiency of the infrared sensor. The reflection pattern 6 may be made of a metal material.

2 and 3 are a cross-sectional view and a perspective view for explaining a process of forming a porous insulating layer, a sensing layer, and electrodes on an insulating layer.

The porous insulating layer 10 is formed on the insulating layer 2. The porous heat insulating layer is formed so as to cover the reflection pattern 6.

The porous heat insulating layer 10 may have a mesoporous structure. The mesoporous structure has pores having an average diameter of 2 to 10 nm. Here, the mesoporous structure collectively refers to a structure having pores having an average diameter of 2 to 10 nm.

In addition, the porous heat insulating layer 10 may have a porosity ranging from 40 to 70%.

The porosity of the porous heat insulating layer 10 can be improved by providing a plurality of pores therein. Furthermore, since the porous insulating layer 10 has a two-dimensional planar structure on the upper portion of the base substrate 1, as compared with an infrared sensor having a conventional three-dimensional floating structure, the infrared sensor has structural stability and manufacturing The process can be simplified.

The porous insulating layer 10 is formed on the insulating film 2 through a sol-gel process. According to the sol-gel process, an oxide solvent including a surfactant is supplied onto the insulating layer 2 through a spin coating process to form a coating layer on the insulating layer 2.

Thereafter, a porous insulation layer 10 is formed on the insulation layer 2 by removing a material remaining in the coating layer by performing a pore formation process for heating the coating layer. According to the pore-forming process, pores are left in the porous heat insulating layer 10 by decomposing the organic material micelle existing in the oxide solvent.

 In the sol-gel process, the porosity of the porous heat insulating layer 10 formed in the subsequent pore forming process can be controlled by controlling the concentration of the surfactant contained in the oxide solvent. That is, as the concentration of the surfactant increases, the porosity of the porous insulating layer 10 can be increased. Therefore, the porosity of the porous heat insulating layer 10 can be easily controlled by changing the porosity of the porous heat insulating layer 10 according to the concentration of the surfactant contained in the oxide solvent.

In one embodiment of the present invention, the oxide solvent may include silicon oxide. For example, the porous heat insulating layer 10 made of silicon oxide and having a porosity of 40% may have a thermal conductivity of 0.18 W / m-K. Generally, since the thermal conductivity of silicon oxide is 1.38 W / m-K, the porous heat insulating layer 10 made of silicon oxide and having porosity of 40% can secure a very low thermal conductivity.

Referring to FIGS. 2 and 3, a sensing layer 11 and electrodes 5 are formed on the porous insulating layer 10.

The sensing layer 11 includes a sensing element whose electrical resistance varies with temperature. For example, the sensing layer 11 may include PZT, BST, and the like. Alternatively, the sensing layer 11 may include a sensing element, a thermocouple sensing element, and a superconducting sensing element whose dielectric constant varies with temperature.

For example, the sensing layer 11 may be formed using lanthanum strontium manganese oxide having pores formed therein. Thus, the sensing layer 11 can be thermally insulated from the outer rotor effectively, thereby having improved sensing characteristics.

The sensing layer 11 may be formed through a thin film deposition process and a patterning process for patterning the thin film. Examples of the thin film deposition process may include a chemical vapor deposition process, an atomic layer deposition process, a sputtering process, and an ion beam deposition process. On the other hand, examples of the patterning process include a photolithography process, a nanoimprinting process, and the like.

The electrodes 5 are connected to both ends of the sensing layer 11, respectively. A change in electrical characteristics of the sensing layer 11 due to infrared rays can be confirmed through the electrodes 5. Accordingly, infrared rays can be detected through the change of the characteristics of the sensing layer 11. [

 4 and 5 are a cross-sectional view and a perspective view for explaining a process of forming an insulating layer, an absorbing layer and a protective layer, which are formed on the porous insulating layer so as to cover the sensing layer and the electrodes.

4 and 5, an insulating layer 4, an absorbing layer 7 and a protective layer 8 are sequentially formed on the porous insulating layer 10 so as to cover the sensing layer 11 and the electrodes 5 do.

The insulating layer 4 is formed using silicon nitride or the like. As a result, the insulating layer 4 can efficiently transfer heat to the sensing layer 11 located under the insulating layer 4. The insulating layer 4 may be formed through a chemical vapor deposition process or the like.

A via contact 9 electrically connected to the electrodes 5 is formed in the insulating layer 4. As a result, the electrodes 5 and the external devices (not shown) can be electrically connected to each other through the bar contact 9.

On the other hand, the absorbing layer 7 is formed on the insulating layer 4. The absorbent layer 7 is made of a material that effectively absorbs ultraviolet rays. For example, the absorbent layer 7 may be made of titanium nitride.

Then, a protective layer 8 is formed on the absorbent layer 7. Thereby, the protective layer 8 can protect the absorbing layer 7 from the outside.

The protective layer 8 is made of silicon oxide. In addition, the protective layer 8 may be made of a porous heat insulating material to suppress heat loss. The protective layer 8 may be made of the same material as the porous insulating layer 11.

The method of manufacturing an infrared sensor according to embodiments of the present invention can be applied to military and night detection fields.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims. It can be understood that it is possible.

Claims (8)

Forming an insulating film on the base substrate;
Forming a reflection pattern on the insulating film;
Forming a porous insulating layer on the insulating film so as to cover the reflection pattern and directly contact the upper surface of the insulating film; And
And forming an infrared ray sensing unit for sensing infrared rays on the porous heat insulating layer,
Wherein the step of forming the porous heat insulating layer is performed through a sol-gel process using an oxide solvent containing a surfactant. The manufacturing method of an infrared sensor according to claim 1, wherein the sol-gel process uses a spin coating process. The manufacturing method of an infrared sensor according to claim 1, wherein the oxide solvent comprises silicon oxide. The manufacturing method of an infrared sensor according to claim 1, wherein the step of forming the porous heat insulating layer controls the porosity of the porous heat insulating layer by controlling the concentration of the surfactant. The method of claim 1, wherein the porous insulating layer has a porosity ranging from 40 to 70%. The method of claim 1, wherein the step of forming the infrared sensing unit comprises:
Forming a sensing layer and electrodes on the porous insulating layer;
Forming an insulating layer on the porous insulating layer to cover the sensing layer and the electrodes;
And sequentially forming an absorbing layer and a protective layer on the insulating layer. The manufacturing method of an infrared sensor according to claim 6, wherein the sensing layer or the protective layer is formed to have a porous structure. [7] The method of claim 6, wherein the sensing layer is formed using lanthanum strontium manganese oxide.

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