KR100759013B1 - Non-contact infrared temperature sensor and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a non-contact infrared temperature sensor, a thermally conductive packaging provided on at least a portion of a sensor unit including a thermo pile, a housing protecting the thermo pile, the bonded sensor unit, and an upper surface and a sidewall surface of the housing. It provides a non-contact infrared temperature sensor and a method for manufacturing the same. As such, the thermally conductive packaging unit conducts and radiates heat above the temperature sensor downward to generate electromotive force of the thermopile only through a pure external heat source, thereby improving precision of temperature measurement.

Infrared, Temperature Sensors, Thermopile, Wafer Bonding, Thermally Conductive Packaging

Description

Non-contact infrared temperature sensor and its manufacturing method {NON-CONTACT IR TEMPERATURE SENSOR AND METHOD FOR MANUFACTRUING THE SAME}

1 is an exploded perspective view of a non-contact infrared temperature sensor according to a first embodiment of the present invention.

2 is a sectional view of a non-contact infrared temperature sensor according to the first embodiment;

3 is a bottom view of the non-contact infrared temperature sensor according to the first embodiment.

4 is a plan view and a sectional view of a sensor unit according to the first embodiment;

5 is a plan view and a sectional view of a sensor unit according to a modification of the first embodiment;

6 is a plan view and a sectional view of a housing part according to the first embodiment;

7 to 9 are cross-sectional views illustrating a method of manufacturing a non-contact infrared temperature sensor according to a first embodiment of the present invention.

10 is an exploded perspective view of a non-contact infrared temperature sensor according to a second embodiment of the present invention.

11 is a sectional view of a non-contact infrared temperature sensor according to the second embodiment.

12 is a plan view, bottom view and cross-sectional view of the housing according to the second embodiment;

13 is a plan view, a bottom view, and a sectional view of a sensor unit according to the second embodiment;

14 to 16 are cross-sectional views illustrating a method of manufacturing a non-contact infrared temperature sensor according to a second embodiment of the present invention.

<Explanation of symbols for main parts of the drawings>

100, 500: sensor 200, 400: housing

300, 700: thermally conductive packaging portion 600: light transmitting portion

The present invention relates to a non-contact infrared temperature sensor and a method for manufacturing the same, which is based on a semiconductor process up to external packaging to minimize the influence of fast response and ambient temperature, thereby improving the precision of temperature measurement. An infrared temperature sensor element relates.

In general, there are two types of methods for measuring temperature, contact and non-contact. Contact thermometers include mercury thermometers, alcohol thermometers, NTC thermometers, and thermocouples and platinum thermometers for industrial applications. I am using a thermometer using).

Thermopile has recently been widely used as a temperature sensor element instead of mercury thermometer, and because of the precise measurement of temperature, fast response speed, and the advantage of being able to measure without touching the heat source, The application range is rapidly expanding to various fields such as temperature measurement of home appliances.

The thermopile senses the temperature by using the Seebeck effect, in which a thermoelectric power in proportion to the magnitude of the temperature difference occurs when a temperature difference occurs between the contacts of two different materials, that is, the cold junction and the hot junction.

An infrared temperature sensor element including a thermo pile was fabricated by implementing a thermocouple as a thin film on a silicon wafer. Therefore, in order to improve the sensitivity of the thermopile, the incident infrared radiation energy must be absorbed as much as possible, and the absorbed energy must be designed so as not to be lost.

In addition, it is essential to accurately compensate the cold junction temperature for more accurate temperature measurements. However, in the case of the conventional thermo pile, the infrared rays incident from the outside touch the silicon wafer as well as the on-contact area to raise the temperature of the silicon wafer, and thus the heat of the silicon wafer is radiated to the on-contact point so that an external heat source (object to be measured) Because of the incorrect recognition of higher temperature than pure water temperature, it is difficult to make accurate temperature measurement.

Therefore, in order to solve the above problems, the present invention bonds a device portion provided with a thermopile and a housing encapsulating the same by a silicon bonding method, and provides a package having excellent thermal conductivity on the side thereof to provide heat at the upper side of the device. It is an object of the present invention to provide a non-contact infrared temperature sensor and a method of manufacturing the same that can be emitted to the bottom to make accurate temperature measurements.

Non-contact infrared temperature comprising a sensor unit including a thermo pile according to the present invention, a housing protecting the thermo pile, and a thermally conductive packaging unit provided on at least a portion of the sensor unit and the upper surface and the sidewall surface of the housing. Provide a sensor.

Here, a thermopile is provided on a semiconductor substrate, and has a sensor portion including an external electrode terminal penetrating the semiconductor substrate and connected to the thermopile, and a concave portion provided above the sensor portion and corresponding to the thermopile. And a portion of an upper surface of the housing bonded to the sensor portion and the wafer and the thermally conductive packaging portion provided on the sensor portion and the sidewall surface of the housing.

A recess is formed in an upper portion of the first semiconductor substrate, a housing having electrode pads penetrating the first semiconductor substrate, and a thermo pile is provided in an area corresponding to the recess in the lower portion of the second semiconductor substrate. The sensor unit may include a sensor unit provided with an internal electrode connecting the pile and the electrode pad, a portion of an upper surface of the sensor bonded wafer, and the thermally conductive packaging unit provided on the sidewall surface of the sensor unit and the housing. In this case, it is further effective to further include a light-transmitting portion bonded to the upper side of the sensor, and the thermally conductive packaging portion is provided on a portion of the upper surface of the light-transmitting portion and the side wall of the light-transmitting portion, the sensor portion, and the housing. In addition, it is effective that an antireflection film and an interference filter film are formed on the surface of the light transmitting part.

The sensor unit and the housing described above are preferably bonded through wafer bonding.

The sensor unit and the housing described above are preferably bonded using an epoxy or glass paste mainly composed of one of Ag, Be, Cu, Au and an alloy containing the same.

The above-mentioned thermally conductive packaging unit is preferably formed of a material film having a thermal conductivity of 100 to 500 W / mK through a semiconductor thin film deposition method. In this case, it is effective to use at least one of Cu, Ag, Au, Ni, Al, and an alloy including the material film.

The sensor unit preferably includes a semiconductor substrate provided with a cavity, a thermo pile provided with a cold contact on the cavity, and an infrared absorbing layer formed on the on contact. At this time, it is preferable to further include a heating wire for heating the semiconductor substrate. And it is preferable to further include the NTC or PCT element provided on the said semiconductor substrate and connected with the thermopile.

In addition, providing a sensor unit including a thermo pile according to the present invention, bonding a housing protecting the thermo pile to the sensor unit, at least a top surface and a side wall surface of the bonded housing and the sensor unit It provides a method of manufacturing a non-contact infrared temperature sensor comprising the step of forming a thermally conductive packaging portion.

The sensor unit and the housing are preferably manufactured on a semiconductor wafer and bonded by a silicon direct bonding method. At this time, in the process of bonding the sensor unit and the housing, it is effective to bond the sensor unit and the housing in close contact with each other and then press and bond them. In addition, the bonding process is preferably performed a heat treatment at a temperature of 300 to 1500 degrees. It is of course effective to carry out the bonding step in a vacuum atmosphere and apply a high voltage. It is preferable to bond between the wafer in which the said some sensor part was formed, and the wafer in which the said some housing was formed.

The thermally conductive packaging portion is preferably formed by a semiconductor thin film deposition method including a sputtering method, an evaporation method, and a CVD method.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Like numbers refer to like elements in the figures.

1 is an exploded perspective view of a non-contact infrared temperature sensor according to a first embodiment of the present invention, Figure 2 is a cross-sectional view of the non-contact infrared temperature sensor according to the first embodiment, Figure 3 is a non-contact infrared temperature according to the first embodiment Bottom view of the sensor. 4 is a plan view and a cross-sectional view of the sensor unit according to the first embodiment, FIG. 5 is a plan view and a cross-sectional view of the sensor unit according to a modification of the first embodiment, and FIG. 6 is a plan view and a cross-sectional view of the housing unit according to the first embodiment.

1 to 6, a non-contact infrared temperature sensor according to a first embodiment of the present invention includes a sensor unit 100 including a thermopile 120 provided on a semiconductor substrate 110, and the sensor unit ( It includes a housing 200 for protecting the thermopile 120 of the 100, a wafer bonded sensor unit 100 and a thermally conductive packaging unit 300 provided on at least a portion of the upper surface and the side surface of the housing 200.

As illustrated in FIG. 4, the sensor unit 100 includes a semiconductor substrate 110, a thermo pile 120 provided on the semiconductor substrate 110, and external electrodes 130a and 130b connected to the thermo pile 120. 130).

The thermo pile 120 may include a plurality of cold junctions 124 and on-contacts 122 provided on the semiconductor substrate 110, and alternately provided between the cold junctions 124 and on-contacts 122. First and second thermocouples 126 and 128. An external electrode 130 connected to the first and second thermocouples 126 and 128, and an infrared absorption layer 140 provided on the on-contact point 122 are included. The protection layer 129 may be further provided on the entire structure including the first and second thermo couples 126 and 128. In addition, an insulating layer 121 provided on the semiconductor substrate 110 may be formed.

In this case, the semiconductor substrate 110 includes a body 111 and a cavity 112 provided at the center of the body 111. In this case, it is preferable that an on-contact point 122 is formed on the insulating film 121 above the cavity 112, and a cold contact 124 is formed on the insulating film 121 above the body part 111. Do. In addition, the infrared absorption layer 140 is preferably provided on the cavity 112. The cavity 112 is formed by removing the central region of the semiconductor substrate 110, but is formed in a rectangular pillar shape as shown in the drawing, and has a shape in which a lower area is wider than an upper area. Do. In addition, the hot contact 122 is effectively provided along the circumference of the cavity 112. Of course, the shape of the cavity 112 is not limited to the above description, and it is possible to have a polygonal pillar shape, a circular pillar shape, and an elliptic pillar shape including a square pillar. In addition, the upper and lower areas may be equal to each other, and the upper area may be larger than the lower area. In this embodiment, it is preferable to use a silicon wafer as the semiconductor substrate 110.

As the insulating layer 121, a thin film having low thermal conductivity is used, but in this embodiment, a silicon nitride film (Si _x N _x ), a silicon oxide film (SiO _x ), a fluoride film (MgF ₂ , CaF ₂ , BaF ₂ ), and sapphire It is preferable to form using at least one thin film of a polymer material film such as a film (Al ₂ O ₃ ), a silicon carbide film (SiC), and a polyimide. The insulating layer 121 may be manufactured in the form of a plurality of thin films stacked. The insulating layer 121 may be formed on the entire surface of the semiconductor substrate 110, and the on-contact point 122 and the cold-contact point 124 may be provided on the semiconductor substrate 110. The 122 may be provided on the insulating film 121, and the cold junction 124 may be provided on the semiconductor substrate 111.

The first and second thermocouples 126 and 128 are connected in series, each component of each thermocouple has a large thermoelectric power, and the first and second thermocouples 126 and 128 have a thermal electromotive force. It is preferred to consist of different materials with opposite polarities. It is preferable that the first and second thermocouples 126 and 128 intersect the hot contact 122 and the cold contact 124, and the hot contact 122 and the cold contact 124 are thermally separated. As illustrated in FIG. 1, first and second thermocouples 126 and 128 are alternately connected in series between the plurality of on-contact contacts 122 and the cold contact 124. For example, a second thermocouple is connected between the first hot junction and the first cold junction, a first thermocouple is connected between the first cold junction and the second cold junction, and a second hot junction and the second cold junction. The second thermocouple is connected in between. Here, the first and second thermocouples 126 and 128 are used as the semiconductor film and the metal thin film, or the first metal thin film and the second metal thin film are used. That is, the first and second thermocouple silicon films and aluminum films, germanium films and aluminum films, Cr films and Al films, Pt films and Rh films can be used. In this case, a silicon film doped with an impurity may be used as the silicon film, or a polysilicon film may be used. The present invention is not limited to the above-mentioned thermocouple, it is also possible to use a thermoelectric conversion element for the thermometer side including a pyroelectric element. In this case, the first and second thermocouples 126 and 128 may be stacked and fabricated.

The first thermo couple 126 described above is connected to the first external electrode 130a, and the second thermo couple 128 is connected to the second external electrode 130b.

In this case, the external electrode 130 includes an electrode part 131 connected to the thermo couples 126 and 128, and a pad part 132 connected to the electrode part 131 to be connected to an external circuit. As shown in the drawing, the electrode part 131 is provided at both edges of the semiconductor substrate 110, and the pad part 132 penetrates through the semiconductor substrate 110 under the electrode part 131. 110) It is provided in the form of extended exposure to the lower side. That is, the pad part 132 is provided through the semiconductor substrate 110 and the insulating film 121. As a result, in the non-contact infrared temperature sensor according to the present exemplary embodiment, as illustrated in FIG. 3, a pad part 132 to be connected to the collecting circuit may be provided on the bottom bottom surface of the sensor. At this time, the pad portion 132 exposed to the outside may be provided in a bump form to facilitate connection with the lower circuit.

The infrared absorption layer 140 is provided on the on-contact point 122 as shown in the drawing to absorb infrared rays from the outside to increase the temperature of the on-contact point 122. The infrared absorption layer 140 is preferably manufactured using at least one of a transition metal including Ni, Co, Fe, Se, or Al, Au, C, Bi, Ir, Ru, RuO _x and IrO _x . In the present exemplary embodiment, a protective film 129 may be further formed between the infrared absorption layer 140 and the on-contact point 122 as shown in the drawing.

The sensor unit 100 is not limited to the above description, and various elements for improving the temperature sensing capability of the sensor unit 100 may be further added.

That is, the sensor unit 100 according to the modified example of the present embodiment illustrated in FIG. 5 provides a separate hot wire 150 on the body portion 111 of the semiconductor substrate 110 to adjust the temperature of the body portion 111. The temperature of the cold junction 123 can be kept constant by maintaining it at a constant level. In this case, the heating wire 150 is provided in various forms in the upper region of the body portion 111 of the semiconductor substrate 110, and separate heating wire power input terminals 151a and 151b to be connected to external power at both ends of the heating wire 150. ) Is provided. In this case, the hot wire power input terminals 151a and 151b may be manufactured in the same structure as the external terminal 130 connected to the thermopile 120 described above, and the connection pad may be disposed below the substrate 110. In addition, the heating wire 150 may be provided between the body 111 and the insulating layer 121 to be separated from the thermo pile 120. Of course, the heating wire 150 may be provided inside the body portion 111. Of course, after forming the hot wire 150 in the body portion 111 may be further formed a separate heat shield for separating it from the thermo pile 120.

In addition, an NTC element 160 may be provided at one side of the body 111 to accurately compensate the temperature of the cold junction region. At this time, the NTC element 160 is preferably provided on a part of the body portion 111 is separated from the thermo pile 120, and is provided on the same plane as the first and second thermo couple (126, 128) Is effective. Then, NTC connection terminals 161a and 161b connected to both terminals of the NTC element 160 are provided. Although the NTC element 160 and the thermopile 120 are separated from each other in FIG. 5, preferably, the NTC element 160 is effectively connected in series with the thermopile 120. That is, the first and second thermocouples 126 and 128 of the thermo pile 120 may be connected in series through separate wirings, and the NTC connection terminals 161a and 161b and the external terminals of the thermo pile 120 may be connected. 130 may also be connected in series.

As shown in FIG. 6, the housing 200 for protecting the sensor unit 100 according to the present embodiment having the above-described structure includes a body portion 210 and a thermopile 120 below the body portion 210. A corresponding recess 220. In addition, the anti-reflection film 230 may be provided on the upper surface of the housing 200. Of course, an anti-reflection film may also be formed on the inner surface of the recess 220.

Here, it is preferable to use a silicon wafer as the housing 200. Through this, the housing 200 and the sensor unit 100 may be coupled through wafer bonding. Therefore, heat generated by the infrared rays irradiated on the upper portion of the housing 200 may be rapidly conducted downward and released to the outside through the wafer bonded housing 200 and the body portions 111 and 210 of the sensor unit 100. have. In other words, the complete bonding between the silicon to increase the thermal conductivity can quickly transfer the heat of the upper side of the housing to the bottom surface of the device. According to the present embodiment, the housing 200 and the sensor unit 100 may be bonded through the wafer bonding, that is, the silicon direct bonding method. However, the present invention is not limited thereto, and the housing 200 may be formed using an adhesive having high thermal conductivity. ) And the sensor unit 100 may be combined.

The body portion 210 is preferably manufactured in the same rectangular parallelepiped form as the sensor portion 100, but is not limited thereto. Various shapes such as a polyhedron and a cylinder are possible. In addition, the housing 200 may have a predetermined recess 220 at a lower side thereof to reduce a distance that external infrared rays penetrate the housing 200 and to thermally isolate the thermopile 120. . And it is effective to make infrared rays concentrate on an on-contact point by a recessed part. As shown in the drawing, the recess 220 preferably has an area of the opening of the recess 220 wider than that of the bottom surface. Of course, the present invention is not limited thereto, and the area of the opening and the bottom may be the same, or the area of the bottom may be larger than that of the opening. The recess 220 is provided in the central region of the housing 200, and the region whose thickness is thinned by the recess 220 serves as a transmission window. The anti-reflection film 230 may be provided only in the transmission window region, that is, the upper region of the bottom surface of the recess 220.

In the present exemplary embodiment, the thermally conductive packaging part 300 is formed on a portion of the upper surface and the sidewall surface of the structure in which the sensor part 100 and the housing 200 of the above-described structure are wafer bonded to each other. The thermally conductive packaging unit 300 is preferably manufactured through various semiconductor thin film formation processes, and it is preferable to use various material films having a thermal conductivity of 100 to 500 W / mK. In the present embodiment, as the thermally conductive packaging portion 300, at least one of Cu, Ag, Au, Ni, Al, and an alloy containing the same, sputtering, evaporation, CVD, etc. It is preferable to form through.

As shown in FIGS. 1 and 2, the thermally conductive packaging part 300 is provided on an upper side of the housing 200, ie, the upper surface of the housing 200 except for the upper region of the recess 220. The body portion 210 and the sensor portion 100 is preferably provided in a shape surrounding the side wall surface of the body portion 112. Of course, the present invention is not limited thereto, and the thermally conductive packaging part 300 may have various shapes that emit heat from the upper surface of the housing 200 to the outside through the side of the device.

In this embodiment, through the thermally conductive packaging unit 300 can accurately measure the temperature of the correct heat source. That is, in general, the infrared rays introduced from the outside are first irradiated to the upper surface of the housing 200 to raise the temperature of the upper surface, and such heat is radiated back to the on-contact point of the thermopile 120 in the form of infrared rays, thereby providing a pure external heat source. There was a problem that is recognized as a temperature higher than the temperature of. However, when the thermally conductive packaging part 300 is provided on a part of the upper surface of the housing 200 and the sidewalls of the housing 200 and the sensor part 100 as in the present embodiment, the upper surface of the housing 200 is provided. The heat generated in can be quickly conducted and released through the thermally conductive packaging 300 to the lower region so that only a pure external heat source can be measured.

As such, the non-contact infrared temperature sensor capable of accurately conducting and releasing heat from the upper surface of the housing to the lower part of the sensor to measure the temperature is preferably manufactured through a semiconductor manufacturing process including a thin film deposition and patterning process. .

The following describes a method of manufacturing a non-contact infrared temperature sensor according to the present embodiment.

7 to 9 are cross-sectional views illustrating a method of manufacturing a non-contact infrared temperature sensor according to a first embodiment of the present invention.

Referring to FIG. 7, a sensor unit 100 having a thermo pile 120 formed on a semiconductor substrate 110 is provided, and a recess 220 corresponding to the thermo pile 120 of the sensor unit 100 is provided. The housing 200 is prepared.

The manufacturing of the sensor unit 100 will be described as follows. The insulating film 121 is formed on the upper surface of the semiconductor substrate 110 by using a thin film having low thermal conductivity. In this embodiment, it is preferable to form the insulating film 121 by depositing a silicon nitride film and a silicon oxide film in plural layers. This is because the myth layer has a compressive stress and the nitride layer has a tensile stress, and when these layers are stacked in multiple layers, a structure that can compensate for each other's stress can form a mechanically stable insulating layer. It becomes possible. In this case, a hot wire may be formed on the surface of the semiconductor substrate 110 before the insulating film 121 is formed.

The semiconductor substrate 110 is patterned to form a cavity 112. To this end, the semiconductor substrate 110 on which the insulating film 121 is formed is turned over, and then a photosensitive film is coated on the surface thereof, and a photoresist mask pattern (not shown) for opening a central region of the semiconductor substrate 110 by performing exposure and development processes. Form. It is preferable to form the cavity 112 by etching the exposed semiconductor substrate 110 using the photoresist mask pattern as an etching mask. In this case, it is effective that the insulating film 121 provided in the region opposite to the semiconductor substrate 110 serves as an etch stop film. The etching of the semiconductor substrate 110 is preferably performed by wet etching using an etchant containing a KOH aqueous solution. Through this wet etching, a cavity 112 having a sidewall inclined at an angle from the bottom of the substrate is provided. In this case, through-holes to be provided with the pad part 132 of the external electrode 130 may be formed at both edges of the body part 111 of the semiconductor substrate 110. In addition, a separate barrier layer (not shown) may be formed on the lower surface of the semiconductor substrate 110 to form the cavity 112.

The thermopile 120 is formed on the insulating layer 121, and the electrode part 131 of the external electrode 130 connected to the thermopile 120 is formed. The first and second thermocouples 126 and 128 are sequentially deposited and patterned on the insulating layer 121 to provide an on-contact point 122 above the cavity 112 and a cold contact 124 above the body 111. It is preferred that the first and second thermocouples 126 and 128 are alternately connected in series between the cold junction 124 and the hot junction 122 to form a thermo file 120. In addition, it is preferable to form an external electrode 130 connected to the thermo pile 120 at both edges of the body 111 of the substrate 110 using a conductive material. In this case, when the insulating film 121 is provided between the electrode portion 131 and the pad portion 132 of the external electrode 130, a process of removing a portion of the insulating film 121 may be further performed for connection therebetween. In addition, the inside of the through hole provided at both edges of the body part 111 may be filled with a conductive material, or a conductive material may be provided on the sidewall thereof to form an external electrode 130 having a pad connected to the outside of the bottom surface of the semiconductor substrate 110. Can be formed.

In this case, the NTC or the PCT device 160 may also be manufactured, and the substrate etching process for manufacturing the cavity 112 of the semiconductor substrate 110 may be performed after the thermopile forming process 120. .

Next, the passivation layer 129 is formed on the insulating layer 121 provided with the thermopile 120, and then the infrared absorption layer 140 is formed on the passivation layer 129. The infrared absorption layer 140 forms at least one of Al, Au, C, Bi, Ir, Ru, RuOx, and IrOx on the passivation layer 129, and then patterns the on-contact point 122 of the thermopile 120. It is preferable to produce in the shape which covers an area | region. Through the above-described manufacturing method to produce a sensor unit 100 as shown in (b) of FIG.

On the other hand, the manufacturing method of the housing 200 will be described. The recess 220 is formed by removing a portion of the lower region of the semiconductor substrate, that is, the body 210. That is, the recess 220 is formed by forming a photoresist pattern on the lower surface of the semiconductor substrate to expose a portion of the semiconductor substrate and then performing an etching process using the photoresist as an etching mask to remove a portion of the semiconductor substrate in the exposed region. . At this time, the width of the semiconductor substrate to be removed is preferably 10 to 90% of the width of the entire semiconductor substrate. Here, the photoresist pattern is preferably the same pattern as the photoresist pattern for forming the cavity 112 described above, and may be a photoresist pattern having a smaller or larger opening. Thereafter, it is preferable to form a housing as shown in FIG. 7A by forming an anti-reflection film 230 on the upper surface of the semiconductor substrate. Of course, the anti-reflection film 230 may also be formed on the inner surface of the recess 220.

Referring to FIG. 8, a housing 200 having a sensor unit 100 having a thermo pile 120 formed on a semiconductor substrate 110 and a concave portion 220 corresponding to the thermo pile 120 through a wafer bonding method. Bond).

It is preferable to attach the silicon wafer constituting the body 111 of the sensor unit 100 and the silicon wafer constituting the body 210 of the housing using a silicon direct bonding (SDB) method.

To this end, the sensor unit 100 and the housing 200 are placed on a predetermined jig so that the upper surface of the sensor unit 100 and the lower surface of the housing 200 face each other. It is preferable to bond between the 100 and the housing 200. In this case, the bonding process is preferably performed in a vacuum state. In addition, during the bonding process, heat treatment may be performed at a temperature of 300 to 1500 degrees. That is, the sensor unit 100 and the housing 200 may be pressurized under a vacuum atmosphere and a temperature of about 800 to 1200 degrees to bond them, and the sensor unit 100 may be bonded under a vacuum atmosphere and a temperature of about 300 to 500 degrees. The housing 200 may be pressed to bond them. When pressurized to a temperature of 300 to 500 degrees, a high voltage of 100 to 10000 V may be applied between the two wafers.

As described above, in the present exemplary embodiment, the recess 220 is provided in the lower central region, the housing 200 having the body 210 to be bonded to the edge region, and the pattern (thermo pile, infrared absorbing layer) in the upper central region. Etc.), and the silicon of the edge portion of the sensor portion 100 and the housing 200 is directly bonded because the bond between the sensor portion 100 provided with the body portion 111 to be bonded to the edge region. In addition, the patterns on the upper side of the sensor unit 100 enter the concave portion 220 in the housing 200 to perform wafer bonding in a state in which a predetermined pattern is formed on the wafer. In addition, the silicon materials are completely bonded to each other so that the heat of the upper side of the housing 200 can be quickly transferred to the lower side of the sensor unit 100 through the body portions 111 and 210, and the sensor unit 100 and the housing 200 of the A separate adhesive member for attachment may not be used.

A plurality of sensor units 100 and a housing 200 according to the present embodiment are each formed on a single wafer at the same time, it is preferable that they are cut and manufactured individually. Subsequently, it is effective to arrange the sensor unit 100 and the housing 200 which are individually cut in the apparatus for wafer bonding described above, and then bond them individually. Of course, the present invention is not limited thereto, and the wafer on which the plurality of sensor parts 100 and the housing 200 are formed is not cut, but the wafer on which the plurality of sensor parts 100 are formed and the wafer on which the plurality of housings 200 are formed are wafers. After bonding through a bonding process, the bonded sensor unit 100 and the housing 200 may be cut by individual elements.

Of course, the above-described sensor unit 100 and the housing 200 are preferably bonded by wafer bonding, but may be bonded using an adhesive having excellent thermal conductivity as necessary. That is, an epoxy or glass paste based on any one of Ag, Be, Cu, Au, and an alloy containing the same may be used.

Referring to FIG. 9, the thermally conductive packaging part 300 is formed on the bonded sensor part 100 and a part of the upper surface and the sidewall surface of the housing 200.

In order to form the thermally conductive packaging unit 300, the bonded sensor unit 100 and the housing 200 are positioned on a predetermined jig, and a mask (not shown) that shields a central area of the upper surface of the housing 200 is provided. After the preparation, a material film having a thermal conductivity of 100 to 500 W / mK is deposited on the surface area of the bonded sensor unit 100 and the housing 200 by sputtering, evaporation, CVD, or the like. It is preferable to form the thermally conductive packaging portion 300. Through this, the thermally conductive packaging part 300 is provided on a portion of the upper surface of the sensor unit 100 and the housing 200 and the sidewall surface which are bonded.

In this case, the area shielded by the mask is preferably an area of the recess 220 of the housing 200 through which the infrared ray can be easily transmitted. This is because the thermally conductive packaging portion 300 is not formed in the region shielded by the mask, and the infrared ray is more easily transmitted. Through this, the infrared rays penetrate the concave portion 220 of the housing 200 and are absorbed by the infrared absorbing layer 140 provided under the concave portion 220 to increase the temperature of the on-contact point 122. At this time, the temperature of the upper side of the housing 200 is increased by the infrared rays, but all the heat raised by the thermally conductive packaging part 300 conducts and is radiated downward to detect an accurate temperature. The mask is not limited to the above-described pattern, and various shapes of patterns may be used to allow a large amount of infrared rays to reach the infrared absorption region of the sensor unit 10. And, as the thermally conductive packaging portion 300 is preferably at least one of Cu, Ag, Au, Ni, Al and alloys containing the same, the thickness of the thermally conductive packaging portion 300 is 0.1 to 1000㎛ It is preferable. The thermally conductive packaging 300 may be formed using a dry plating method.

In the above description, the plurality of bonded sensor units 100 and the housing 200 are disposed on the jig supporting them, and then the masks are aligned to form the thermally conductive packaging unit 300. That is, although the thermally conductive packaging part 300 is formed on the outer surface of the sensor part 100 and the housing 200 which are individually cut and bonded, the present embodiment is not limited thereto, and as described above, the plurality of sensor parts After bonding the wafer on which the 100 is formed and the wafer on which the plurality of housings 200 are formed, a portion of the bonded wafer is removed to separate the individual devices. For example, when the total thickness of the bonded wafer is 1, the wafers in the region between adjacent devices are removed by 0.6 to 0.95 thickness to separate the devices. Subsequently, a mask may be formed on the housing 200, the thermally conductive packaging part 300 may be formed on the entire structure, and the individual wafers may be manufactured by cutting the wafer based on the separated regions between the devices through a cutting process.

As such, the present invention fabricates a plurality of structures constituting the non-contact infrared temperature sensor using a silicon wafer, combines them through wafer bonding, and forms thermally conductive packaging on a portion of the top and sidewall surfaces of the joined structures. The precision of temperature measurement of the temperature sensor can be maximized. Of course, the structure of the structure is not limited to the above-described embodiment, thermal isolation of the thermopile, and various structures that can be produced using a semiconductor manufacturing process is possible. Hereinafter, a non-contact infrared temperature sensor according to a second embodiment of the present invention will be described. In the following description, descriptions overlapping with the above description will be omitted, and the description of the second embodiment may be applied to the above-described first embodiment.

10 is an exploded perspective view of a non-contact infrared temperature sensor according to a second embodiment of the present invention, and FIG. 11 is a cross-sectional view of the non-contact infrared temperature sensor according to the second embodiment. 12 is a plan view, bottom view and cross-sectional view of the housing according to the second embodiment. 13 is a plan view, a bottom view, and a sectional view of a sensor unit according to a second embodiment.

10 to 13, the non-contact infrared temperature sensor according to the second embodiment of the present invention includes a housing 400 including a recess 412, electrode pads 420 and 430, and a thermopile ( At least the top and sidewall surfaces of the sensor unit 500 including the sensor unit 520, the light transmitting unit 600 transmitting infrared rays, the wafer bonded light emitting unit 600, the sensor unit 500, and the housing 400. It includes a thermally conductive packaging portion 700 provided in a portion.

12, the housing 400 includes a semiconductor substrate 410 including a body portion 411 and a recess 412, and an electrode pad provided through an edge region of the semiconductor substrate 410. 420, 430. (A) is a top view of a housing, (b) is a bottom view, (c) is sectional drawing.

The concave portion 412 may be manufactured by removing a portion of the upper central region of the semiconductor substrate 410, but the opening portion may be made larger than the area of the bottom surface of the concave portion 412. In addition, the electrode pad parts 420 and 430 may be formed by providing a through hole penetrating the body part 411 and embedding an electrically conductive material therein. In this case, bumps may be provided in an area of the electrode pads 420 and 430 exposed to the lower portion of the housing 400. Here, it is preferable to use a silicon wafer as the semiconductor substrate.

As illustrated in FIG. 13, the sensor unit 500 includes a semiconductor substrate 510, a thermo pile 520 provided under the semiconductor substrate, and internal electrodes 531 and 532 connected to the thermo pile 520. Include. (A) is a top view of a sensor part, (b) is a bottom view, (c) is sectional drawing.

Here, the thermo pile 520 is preferably provided with the same structure as the above-described embodiment as shown in the figure. Although the first and second thermocouples 526 and 528 are provided on the same plane in the above-described embodiment, the present invention is not limited thereto, and the first and second thermocouples 526 and 528 are stacked. It can be prepared as. That is, the plurality of first thermo couples 526 overlap the portion of the cavity 512 on the insulating layer 521, and a separator (not shown) is formed on the first thermo couple 526. A plurality of second thermo couples 528 may be provided on the separator. In this case, the first and second thermo couples 526 and 528 are provided with a predetermined contact on the cavity 512, and the contact is an on-contact point 522, and a contact is provided on the body part 511. This contact may be a cold junction 524. The plurality of first and second thermocouples 526 and 528 of the laminated structure are preferably connected in series alternately. A portion of the first and second thermocouples 526 and 528 are preferably extended to be connected to the internal electrodes 531 and 531 provided at both edges of the semiconductor substrate 510.

In the present exemplary embodiment, the recess 412 of the housing 400 may be provided below the thermo pile 520 to be thermally isolated, and the cavity 512 of the semiconductor substrate 510 may be isolated from the thermo pile 520. The infrared rays provided from the outside may be concentrated on the infrared absorption layer 540 provided on the on-contact point 522. In this case, a material having excellent light reflection characteristics may be coated on the inner sidewall surface of the cavity 512 to increase the amount of infrared rays absorbed by the infrared absorption layer 540.

It is preferable that the above-mentioned light transmitting part 600 is manufactured in a thin plate shape as shown in FIGS. 10 and 11 and provided on the upper side of the sensor part 500. It is effective to use a silicon wafer in this embodiment as the light transmitting part 600. In addition, an anti-reflection film (not shown) may be coated on the light transmitting part 600 to prevent reflection of light that may occur on surfaces of different materials. In addition, an interference filter film (not shown) that transmits only light of a specific wavelength may be coated on the surface thereof. In the present embodiment, the light transmitting part 600 may be omitted as necessary.

In the present embodiment, it is preferable to combine the housing 400, the sensor unit 500, and the light transmitting unit 600 sequentially through wafer bonding so as to achieve complete bonding between silicon. Through this, the thermal conductivity between the light transmitting part 600, the sensor part 500, and the housing 400 is increased to rapidly heat heat generated from the surface of the light transmitting part 600 to the lower part of the housing 400 by ultraviolet rays emitted from the outside. Since it can be transmitted, it is possible to solve the problem that the precision of the temperature sensor due to heat generated in the light emitting unit 600 irradiated with ultraviolet rays is reduced.

The above-described thermally conductive packaging part 700 is provided in a portion of the upper surface and sidewall surface of the wafer-bonded housing 400, the sensor part 500, and the light transmitting part 600, as shown in FIGS. 1 and 2. It is desirable to be. The thermally conductive packaging part 700 provided on the top surface of the light transmitting part 600 may be provided in a pattern corresponding to the body part 411 of the lower sensor part 500 to maximize the inflow of infrared rays. Due to the thermally conductive packaging unit 700 as described above, the heat of the upper side of the light transmitting unit 600 may be quickly released to the outside, thereby improving the temperature measurement accuracy of the temperature sensor.

Hereinafter, a method of manufacturing a non-contact infrared temperature sensor in which a housing, a sensor unit, and a light-transmitting unit are laminated and sequentially bonded and a thermally conductive packaging unit surrounding the same will be described.

14 to 16 are cross-sectional views illustrating a method of manufacturing a non-contact infrared temperature sensor according to a second embodiment of the present invention.

Referring to FIG. 14, a sensor unit 500 in which a housing 400 having a recess 412 and electrode pads 420 and 430 is provided, and a thermopile 520 is provided in an area corresponding to the recess 412. ) And a light transmitting part 600 that transmits ultraviolet rays.

The housing 400 forms a recess 411 by removing a portion of the semiconductor substrate 410 through a predetermined patterning process, and forms a through hole penetrating through the edge region of the semiconductor substrate 410, and then electrically The electrode pads 420 and 430 are formed by filling with a conductive material. It is preferable to form a recess 411 by providing a mask for opening a central region on the semiconductor substrate 410 and then etching by using a mask to remove a part of the exposed semiconductor substrate 410. Then, a mask is formed on the semiconductor substrate 410 to open a portion of both edge regions thereof, and an etching process using the same is used to remove the exposed semiconductor substrate 410 to form a through groove, and a conductive material inside the through groove. The electrode pads 420 and 430 are formed by filling the conductive material or by applying a conductive material to a part of the sidewall of the through hole. Through this, the housing 400 having the recess 411 provided on a part of the upper surface is manufactured.

The sensor unit 500 forms an insulating film 521 under the semiconductor substrate 510, forms a mask on the substrate 510, and then removes the semiconductor substrate 510 in the exposed area, thereby removing the cavity portion ( 512). Thereafter, the semiconductor substrate 510 is turned upside down, and then the first and second thermocouples 526 and 528 are deposited and patterned on the insulating layer 521, and the first and second thermocouples 526 and 528 are respectively connected. Internal electrodes 531 and 532 are formed at both edges of the substrate 510, respectively. Thereafter, the infrared absorbing layer 540 is formed on the on-contact points 522 of the first and second thermocouples 526 and 528 to manufacture the sensor unit 500. In this case, the passivation layer 529 may be provided between the first and second thermocouples 526 and 528 and the infrared absorption layer 540. When the protective film 529 is provided, part of the protective film 529 is removed to form internal electrodes 531 and 532 connected to the first and second thermocouples 526 and 528. By doing so, the internal electrodes 531 and 532 may be connected to the electrode pads 420 and 430 of the housing 400. At this time, the cavity 512 may be manufactured by etching after forming a thermopile.

It is preferable that the above-mentioned light transmitting part 600 is produced by cutting a semiconductor substrate into a plate shape.

Referring to FIG. 15, the housing 400, the sensor unit 500, and the light transmitting unit 600 are coupled to each other through wafer bonding.

Each of these wafer bonding methods can be performed in various ways. That is, the housing 400 and the sensor unit 500 may be first bonded, and then the light transmitting unit 600 may be bonded, or the housing 400 and the sensor unit 500 and the light transmitting unit 600 may be bonded together. The above-described bonding method is omitted because it overlaps with the above-described embodiment.

Meanwhile, in the above description, the internal electrodes 531 and 532 of the sensor unit 500 and the electrode pads 420 and 430 of the housing 400 are manufactured, respectively, and then electrically connected during wafer bonding. However, the present invention is not limited thereto, and a via hole (not shown) may bond the housing 400, the sensor unit 500, and the light transmitting unit 600 through wafer bonding, and then expose the thermopile 520 of the sensor unit 500. After the formation of the and then buried in an electrically conductive material to produce the internal electrodes (531, 532) and electrode pads (420, 430) at the same time.

Referring to FIG. 16, the thermally conductive packaging part 700 is formed on a portion of the upper and sidewalls of the bonded housing 400, the sensor part 500, and the light transmitting part 600.

This is achieved by forming a mask on the bonded light-transmitting part, and then depositing various material films having a thermal conductivity of 100 to 500 W / mK by sputtering, vapor deposition, and CVD to bond a portion of the upper surface of the light-transmitting part to a housing and a sensor. It is preferable to form a thermally conductive packaging part on the side wall surface of the part and the light transmitting part.

At this time, the area shielded through the mask is preferably the upper region of the body portion of the sensor unit. This is effective to have a maximum area that does not interfere with the transmission of infrared rays.

As described above, the present invention may bond a sensor unit having a thermopile on a semiconductor substrate and a housing made of the semiconductor substrate through wafer bonding, so that a separate adhesive member may not be used, and the sensor may be bonded through silicon. The thermal conductivity between the part and the housing is increased to quickly transfer heat from the upper side of the housing to the bottom surface of the device.

In addition, a thermally conductive packaging portion may be formed on the bonded sensor portion and a part of the upper surface and the sidewall surface of the housing, thereby dissipating heat from the upper portion irradiated first by infrared rays, thereby rapidly dissipating heat from the sensor portion and the housing peripheral portion. It can emit precisely and measure only pure external heat source, so it can measure temperature precisely.

In addition, it is possible to improve the sensing capability of the sensor by providing a recess in the housing, by forming a cavity in the lower portion of the sensor portion provided with an on-contact point to thermally isolate the thermopile of the sensor.

In addition, by providing a cavity having an inclined surface in the upper direction of the thermo pile irradiated with infrared rays, it is possible to concentrate the infrared rays at the on-contact point to improve the temperature measurement efficiency.

Although the invention has been described with reference to the accompanying drawings and the preferred embodiments described above, the invention is not limited thereto, but is defined by the claims that follow. Accordingly, one of ordinary skill in the art may variously modify and modify the present invention without departing from the spirit of the following claims.

Claims (18)

A sensor unit including a thermo file; A housing protecting the thermo pile; And And a thermally conductive packaging portion provided on at least a portion of the upper and sidewall surfaces of the housing and the sensor portion bonded through wafer bonding. A sensor unit including a thermo file; A housing protecting the thermo pile; And A thermally conductive packaging portion in contact with at least a portion of the sensor portion and the upper and sidewall surfaces of the housing, The sensor unit and the housing is a non-contact infrared temperature sensor bonded using an epoxy or glass paste mainly composed of any one of Ag, Be, Cu, Au and an alloy containing the same. The method according to claim 1 or 2, A sensor unit provided on a semiconductor substrate, the sensor unit including an external electrode terminal penetrating the semiconductor substrate and connected to the thermo pile; A housing provided above the sensor unit and having a recess corresponding to the thermo pile; A non-contact infrared temperature sensor comprising a portion of an upper surface of the housing bonded with the sensor portion and the thermally conductive packaging portion provided on the sensor portion and the sidewall surface of the housing. The method according to claim 1 or 2, A housing having a recess formed in an upper portion of the first semiconductor substrate, the housing having an electrode pad passing through the first semiconductor substrate; A sensor part provided at a region corresponding to the concave part under the second semiconductor substrate, and a sensor part provided with an internal electrode connecting the thermo file and the electrode pad; A non-contact infrared temperature sensor comprising a portion of an upper surface of the sensor portion bonded to the wafer, and the thermally conductive packaging portion provided on the sidewall surface of the sensor portion and the housing. The method according to claim 4, Further comprising a light transmitting portion bonded to the upper side of the sensor, The non-contact infrared temperature sensor is provided with the thermally conductive packaging portion on a portion of the upper surface of the light transmitting portion and the side wall surface of the light transmitting portion, the sensor portion and the housing. The method according to claim 4, Non-contact infrared temperature sensor is formed on the surface of the light-transmitting antireflection film and the interference filter film. The method according to claim 1 or 2, Non-contact infrared temperature sensor using a silicon wafer as the sensor unit and the housing. The method according to claim 1 or 2, The thermally conductive packaging unit is a non-contact infrared temperature sensor for forming a material film having a thermal conductivity of 100 to 500 W / mK through a semiconductor thin film deposition method. The method according to claim 8, The material film is a non-contact infrared temperature sensor using at least any one of Cu, Ag, Au, Ni, Al, and an alloy containing the same. The method according to claim 1 or 2, The sensor unit and the semiconductor substrate is provided with a cavity; A non-contact infrared temperature sensor comprising a thermopile provided on the cavity, a thermopile provided with a cold junction on the semiconductor substrate, and an infrared absorption layer formed on the on-contact. The method according to claim 10, Non-contact infrared temperature sensor further comprises an NTC or PTC element provided on the semiconductor substrate and connected to the thermopile. Providing a sensor unit including a thermo file; Bonding the housing protecting the thermo pile to the sensor unit; And forming a thermally conductive packaging portion in at least a portion of the bonded housing and the top and sidewall surfaces of the sensor portion. The method according to claim 12, The sensor unit and the housing are manufactured on a semiconductor wafer, A method of manufacturing a non-contact infrared temperature sensor bonded through a silicon direct bonding method. The method according to claim 13, Bonding the sensor unit and the housing, A method for manufacturing a non-contact infrared temperature sensor for bonding the sensor unit and the housing in close contact with each other and then pressing them to bond them. The method according to claim 13, The bonding process is a method of manufacturing a non-contact infrared temperature sensor that performs a heat treatment at a temperature of 300 to 1500 degrees. The method according to claim 13, The said bonding process is performed in a vacuum atmosphere, and the manufacturing method of the non-contact infrared temperature sensor which applies a high voltage. The method according to claim 13, A method for manufacturing a non-contact infrared temperature sensor for bonding between a wafer on which a plurality of sensor portions are formed and a wafer on which a plurality of housings are formed. The method according to claim 12, The thermally conductive packaging portion is formed by a semiconductor thin film deposition method comprising a sputtering (evaporation) method, evaporation (evaporation) method and CVD method.

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