JP6541375B2 - Wireless temperature sensor and method of manufacturing the same - Google Patents

Description

  The present invention relates to a wireless temperature sensor and a method of manufacturing the same.

  There are several methods for temperature measurement using a wired cable. As an example, a method of utilizing temperature-resistance characteristics or thermoelectromotive force by a thermistor or thermocouple, a radiation thermometer that measures temperature from infrared rays emitted from an object, physical characteristics of a piezoelectric element or surface acoustic wave element depending on temperature There are methods that use the changing principle.

  However, for example, in the case of measuring the temperature of a wafer in a chamber in a semiconductor process, the arrangement of a wired cable connected to output from the measurement unit disposed in the chamber to the outside is restricted by the chamber and associated devices. I will receive it. As a solution to this problem, a wireless temperature sensor is known in which a unit provided with a transmitting / receiving antenna in a surface acoustic wave element operates with a signal transmitted from an external antenna and sends back a response signal including measurement information. . (For example, refer to patent document 1)

  FIG. 27 (a) is a plan view of the container main body 101 of the temperature sensor in the first specific example described in Patent Document 1, and FIG. 27 (b) is a plan view of the lid 107. As shown in FIG. 27A, the electrodes attached to the diaphragm 104 and the external terminals 102 and 103 attached to the container body 101 are connected by lead wires 105 and 106, respectively. Further, as shown in FIG. 27B, both ends of the coil 108 formed on the lid 107 and the external terminals 102 and 103 shown in FIG. 27A are connected by lead wires not shown.

  FIG. 27C is a cross-sectional view of the temperature sensor in the second specific example described in the same patent document and is a cross-sectional view before the lid 125 is airtightly sealed to the container main body 121. The diaphragm 123 includes a groove 130 and is attached to the container body 121. A coil 126 is formed on the lid 125. The diaphragm 123 is attached to the container body 121, connected to the external terminal 122 by the lead wire 124, and after the external terminal 122 and the coil 126 are connected by the lead wire 128, the container body 121 and the lid 125 are hermetically sealed. Be done.

  In any of the above first and second embodiments, the coil (108 or 126) provided on the lid (107 or 125) and the diaphragm (104 or 123) provided on the container body (101 or 121) And are connected by leads.

Patent No. 5341381 gazette

  However, in the manufacturing method in which the lid is mounted on the container body so that the lead wire is stored in the container after connecting the lid and the container body separately prepared as a separate body, the lead wire is bent at the time of mounting. In some cases, broken lead wires may come into contact with the diaphragm to cause malfunction after mounting.

  An object of the present invention is to solve the above-mentioned problems, and to provide a wireless temperature sensor that is easy to manufacture and has improved reliability.

  A method of manufacturing a wireless temperature sensor according to the present invention comprises the steps of preparing a first structure and a second structure including an insulating substrate, and arranging an antenna electrode and a GND electrode on the first structure including the insulating substrate. Forming the antenna, fixing the temperature detection element to the first structure so that the temperature detection element is electrically connected to the antenna electrode and the GND electrode, and Bonding and assembling the first structure and the second structure so as to be disposed on the side wall side of the detection element.

  According to the above-described configuration, the temperature detection element is fixed to the first structure in which the antenna electrode and the GND electrode are provided on the insulating substrate, so that the manufacturing is easy and the wireless temperature sensor with improved reliability is manufactured. can do.

  In the method of manufacturing the wireless temperature sensor, the step of joining and assembling the first structure and the second structure further includes the step of bringing the temperature detection element into contact with the inside of the second structure constituting the container. Joining and assembling the first structure and the second structure may be included.

  The above configuration makes it possible to manufacture a wireless temperature sensor in which the response of temperature measurement is further improved.

  In a method of manufacturing a wireless temperature sensor, the second structure may have an opening opposite to the side to be bonded to the first structure.

  The above configuration makes it possible to manufacture a wireless temperature sensor in which the response of temperature measurement is further improved.

  In the method of manufacturing a wireless temperature sensor, the step of joining and assembling the first structure and the second structure further includes disposing a heat conductor between the second structure and the temperature detection element. , Joining and assembling the first structure and the second structure.

  The above configuration makes it possible to manufacture a wireless temperature sensor in which the response of temperature measurement is further improved.

  In a method of manufacturing a wireless temperature sensor, the second structure may have a porous structure or a mesh structure.

  The above configuration makes it possible to more accurately measure the environmental temperature (ambient temperature).

  In the method of manufacturing the wireless temperature sensor, in the step of forming the antenna, a conductor pattern to be an antenna electrode is further disposed on one surface of the insulating substrate, and a conductor pattern to be a GND electrode is disposed in an inner layer of the insulating substrate. A first via hole electrically connected to the antenna electrode and a second via hole electrically connected to the GND electrode are formed in the insulating substrate, and a first electrode pad electrically connected to the first via hole and the second via hole are formed on the other surface of the insulating substrate. The method may include forming a second electrode pad electrically connected to the second via hole.

  According to the above configuration, a patch antenna excellent in transmitting and receiving functions is constituted by the antenna electrode formed on the insulating substrate and the GND electrode formed in the insulating substrate, so that a wireless temperature sensor with improved antenna characteristics is manufactured. Can.

  In the method of manufacturing the wireless temperature sensor, the step of forming the antenna further includes, on the other surface of the insulating substrate, electrically connected to the second electrode pad, and thermally on the temperature detection element and the second structure. It may include forming a heat conduction layer to connect.

  According to the above configuration, since the heat transmitted in the second structure is efficiently transmitted to the temperature detection element through the heat conduction layer, it is possible to manufacture a wireless temperature sensor with improved responsiveness and followability of temperature measurement.

  In the method of manufacturing the wireless temperature sensor, the step of fixing the temperature detection element to the first structure may further include fixing the temperature detection element above the second via hole on the heat conduction layer.

  According to the above configuration, it is possible to reduce the amount of heat transferred to the inside of the lid by the via hole, so that the response of temperature measurement is improved, and a wireless temperature sensor with reduced variation in antenna characteristics due to the influence of heat is provided. It can be manufactured.

  In the wireless temperature sensor according to the present invention, a first structure having an antenna in which an antenna electrode and a GND electrode are disposed on an insulating substrate, and a surface of the first structure on which the antenna electrode is disposed are fixed on the back side. The temperature detection element, and the second structure disposed on the side wall of the temperature detection element and joined to the first structure, and the temperature detection element includes the antenna electrode and the GND electrode. It is characterized in that it is fixed to the first structure so as to be electrically connected.

  According to the above configuration, since the temperature detection element is fixed to the first structure in which the antenna electrode and the GND electrode are provided on the insulating substrate, a wireless temperature sensor which is easy to manufacture and has improved reliability is provided. can do.

  In a wireless temperature sensor, the temperature detection element may be fixed to the inside of the container so as to contact the inside of the second structure.

  According to the above configuration, it is possible to provide a wireless temperature sensor in which the response of temperature measurement is further improved.

  In a wireless temperature sensor, the second structure may have an opening opposite the side bonded to the first structure.

  According to the above configuration, it is possible to provide a wireless temperature sensor in which the response of temperature measurement is further improved.

  The wireless temperature sensor may further comprise a thermal conductor disposed between the second structure and the temperature sensing element.

  According to the above configuration, it is possible to provide a wireless temperature sensor in which the response of temperature measurement is further improved.

  In a wireless temperature sensor, the second structure may have a porous structure or a mesh structure.

  The above configuration makes it possible to more accurately measure the environmental temperature (ambient temperature).

  The wireless temperature sensor may further comprise a thermally conductive layer formed on the insulating substrate and thermally connected to the temperature sensing element and the second structure.

  According to the above configuration, since the heat transmitted in the second structure is efficiently transmitted to the temperature detection element through the heat conduction layer, it is possible to provide a wireless temperature sensor with improved responsiveness and followability of temperature measurement.

  The wireless temperature sensor may further include a via hole formed in the insulating substrate and in communication with the GND electrode and the heat conduction layer, and the temperature detection element may be fixed on the via hole on the heat conduction layer.

  According to the above configuration, it is possible to reduce the amount of heat transferred to the inside of the lid by the via hole, so that the response of temperature measurement is improved, and a wireless temperature sensor with reduced variation in antenna characteristics due to the influence of heat is provided. It can be manufactured.

  According to the present invention, since the temperature detection element is fixed to the first structure in which the antenna electrode and the GND electrode are provided on the insulating substrate, the wireless temperature sensor is easy to manufacture and has improved reliability. Can be provided.

It is a figure for demonstrating the structure of the wireless temperature sensor 1. FIG. (A) is a plan view of the temperature detection element 30, (b) is a cross-sectional view of the temperature detection element 30 along the line C-C shown in FIG. 2 (a), (c) is a temperature detection element 30 FIG. 2 (a) is a cross-sectional view taken along the line D-D shown in FIG. It is a top view of the wireless temperature sensor 1, (b) is a side view of the wireless temperature sensor 1. FIG. 4 is a cross-sectional view of the wireless temperature sensor 1 taken along the line B-B shown in FIG. It is a figure for demonstrating the temperature detection method by the wireless temperature sensor 1. FIG. It is a graph which shows the time change of reflective surface acoustic wave intensity Rwp in a surface acoustic wave element. It is a figure for demonstrating the structure of the temperature measurement system which used the wireless temperature sensor 1. FIG. It is a flowchart which shows the outline | summary of the manufacturing process of the wireless temperature sensor 1. FIG. It is a figure for demonstrating the 1st structure assembly process of the wireless temperature sensor 1. FIG. It is a figure for demonstrating the temperature detection element mounting process of the wireless temperature sensor 1. FIG. It is a figure for demonstrating the container assembly process of the wireless temperature sensor 1. FIG. FIG. 6 is a diagram for explaining the structure of another wireless temperature sensor 2; FIG. 6 is a diagram for explaining a first structure assembling step of the wireless temperature sensor 2; It is a figure for demonstrating the structure of other wireless temperature sensor 3 further. (A) is a cross-sectional view schematically showing the propagation path of heat from the measurement object (not shown) of the wireless temperature sensor 2. (b) is the propagation of heat from the measurement object (not shown) of the wireless temperature sensor 3. It is sectional drawing which represented the path | route typically. It is a figure for demonstrating the structure of other wireless temperature sensor 4 further. It is a figure for demonstrating the manufacturing method of the wireless temperature sensor 4. FIG. It is a figure for demonstrating the structure of other wireless temperature sensor 5 further. It is a figure for demonstrating the temperature detection element mounting process of the wireless temperature sensor 5. FIG. It is a figure for demonstrating the structure of other wireless temperature sensor 6 further. It is the figure which looked at the wireless temperature sensor 6 from direction 6D of FIG. It is a figure for demonstrating the structure of other wireless temperature sensor 7 further. It is the figure which looked at the wireless temperature sensor 7 from direction 7D of FIG. It is a figure for demonstrating the structure of other wireless temperature sensor 8 further. It is a figure for demonstrating the temperature detection element mounting of the wireless temperature sensor 8, and a general assembly process. It is a figure for demonstrating the structure of other wireless temperature sensor 9 further. It is a top view which shows the piezoelectric vibrator of a prior art example, a temperature sensor, and the temperature measurement method.

  Hereinafter, embodiments of the wireless temperature sensor according to the present invention will be described in detail with reference to the drawings. However, it should be noted that the technical scope of the present invention is not limited to those embodiments, but extends to the invention described in the claims and the equivalents thereof. The dimensions of the drawings do not reflect the exact dimensions, and the size of the parts may be exaggerated for the sake of explanation, and some parts may be omitted for the sake of explanation. The same elements will be denoted by the same numbers and redundant description will be omitted.

  FIG. 1 is a diagram for explaining the structure of the wireless temperature sensor 1. The view shown in FIG. 1 is a cross-sectional view of the wireless temperature sensor 1 along the line A-A shown in FIG.

  As shown in FIG. 1, the wireless temperature sensor 1 has a container 50 including a lid 10 and a container body 20, and a temperature detection element 30 fixed to the inside of the container 50. The temperature detection element 30 is mounted on the lid 10.

  The lid 10 is a first structure, and is a microstrip antenna (hereinafter referred to as an antenna) formed by laminating the antenna electrode layer 11 and the GND electrode layer 13 on the insulating substrate 12. The microstrip antenna is also referred to as a planar antenna or a patch antenna, and is an antenna having a high gain and a narrow band and wide directivity, which can be miniaturized and thinned.

Insulating substrate 12 has a thickness of approximately 1 mm, are generally formed by LTCC (Low Temperature Cofired Ceramics) is a low temperature co-fired ceramic material known as _{CaO-Al 2 O 3 -SiO 2} -B 2 O 3 Ru. However, the present invention is not limited to this, and the insulating substrate 12 may be formed using another LTCC. Other _{LTCC, BaO-Al 2 O 3} -SiO 2 -Bi 2 O 3, BaOTiO 2 -ZnO, and _{BaO-Nd 2 O 3 -Bi 2} O 3 -TiO 2, BaO-R 2 O 3 -TiO ₂ (R is an alkali metal) etc. is included.

  The thickness of the insulating substrate 12 is not limited to about 1 mm, and varies depending on the ceramic material used, but it may be a thickness sufficient to secure the characteristics as an antenna.

The insulating substrate 12 may be formed using a high thermal conductivity high temperature fired ceramic material generally known as High Temperature Cofired Ceramics (HTCC). HTCC includes, for example, aluminum oxide (Al ₂ O ₃ ) and aluminum nitride (AlN).

  The antenna electrode layer 11 is an electrode layer made of Cu and having a thickness of about 10 to 15 μm. The antenna electrode layer 11 may have another thickness. The antenna electrode layer 11 is electrically connected to the antenna connection pad 15a which is the first electrode pad provided on the lid mounting surface 15m of the insulating substrate 12 through the antenna via hole 11h which is the first via hole penetrating the insulating substrate 12. It is connected to the. The antenna via hole 11 h and the antenna connection pad 15 a are formed of Cu.

  The GND electrode layer 13 is an electrode layer made of Cu and having a thickness of about 10 to 15 μm. The GND electrode layer 13 may have another thickness. The GND electrode layer 13 is electrically connected to the GND connection pad 15b which is a second electrode pad provided on the lid mounting surface 15m of the insulating substrate 12 through a GND via hole 13h which is a second via hole provided in the insulating substrate 12. Connected. The GND electrode layer 13 includes a GND pattern opening 13 w for penetrating the antenna via hole 11 h. The GND pattern opening 13 w may be filled with a ceramic material for forming the insulating substrate 12. The GND via hole 13 h and the GND connection pad 15 b are formed of Cu.

  The above-described conductor patterns (that is, the antenna electrode layer 11, the antenna via hole 11h, the antenna connection pad 15a, the GND electrode layer 13, the GND via hole 13h, and the GND connection pad 15b) are formed using Cu. Other metals may be used. It is preferable to use Ag or Cu having high electrical conductivity for the conductor pattern. In particular, when LTCC is used for the insulating substrate 12 of the lid 10, by using Ag or Cu having high electrical conductivity, efficient antenna characteristics can be obtained.

The container body 20 is a second structure and is formed of Al ₂ O ₃ which is a high temperature fired ceramic material commonly known as HTCC. A main body cavity 20c is formed in the container main body 20 by a method described later. Not only Al ₂ O ₃ but also other HTCC such as aluminum nitride (AlN) can be used for the container body 20.

  Furthermore, the container main body 20 may be formed not only from HTCC but also from other ceramic materials such as the above-mentioned LTCC, a rigid substrate having a high dielectric constant, a polymer material such as polyimide, and a metal having an oxide film. .

  The temperature detection element 30 is mounted on the lid mounting surface 15 m of the insulating substrate 12 of the lid 10. The temperature detection element 30 has element bonding pads 34a and 34b. The element bonding pad 34a is connected to the antenna connection pad 15a which is a first electrode pad by a bonding wire 35a. The element bonding pad 34b is connected to the GND connection pad 15b which is a second electrode pad by the bonding wire 35b. Therefore, the element bonding pad 34 a is electrically connected to the antenna electrode layer 11, and the element bonding pad 34 b is electrically connected to the GND electrode layer 13.

  2 (a) is a plan view of the temperature detection element 30, and FIG. 2 (b) is a cross-sectional view of the temperature detection element 30 along the line C-C shown in FIG. 2 (a). 2 is a cross-sectional view of the temperature detection element 30 taken along the line D-D shown in FIG.

  In FIG. 2A, the temperature detection element 30 is a surface acoustic wave element, and has a surface acoustic wave element substrate 31, interdigital electrodes 32a and 32b provided on the surface of the surface acoustic wave element substrate 31, and a reflector 33. . An element bonding pad 34a is formed at an end of the comb electrode 32a, and an element bonding pad 34b is formed at an end of the comb electrode 32b. The surface acoustic wave element substrate 31 has side walls 31 a formed of four surfaces substantially perpendicular to the surfaces on which the comb electrodes 32 a and 32 b and the reflector 33 are provided.

The surface acoustic wave element substrate 31 is formed of a single crystal of lithium niobate (LiNbO ₃ ), and has a rectangular plate shape having a size of about 10 mm × 10 mm in plan view and a thickness of about 2 mm. The surface acoustic wave element substrate 31 is not limited to this, and a single crystal substrate of a piezoelectric substance, or a substrate in which a thin film of a piezoelectric substance is formed on a glass substrate or a Si substrate may be used. The piezoelectric material, for example, lithium tantalate (LiTaO _3), quartz (SiO _2), langasite _{(La 3 Ga 5 SiO 14)} , including but such Rangateito _{(La 3 Ta 0.5 Ga 5.5 O} 14), It is not restricted to these.

  The comb-shaped electrode 32 a and the comb-shaped electrode 32 b are formed on one surface of the surface acoustic wave element substrate 31 such that two pairs of electrodes are alternately arranged. The comb-shaped electrode 32a and the comb-shaped electrode 32b are formed by sputtering using Cu. However, the comb electrodes 32a and 32b may be formed using an electrode material other than Cu, such as Au, Ti, Ni, chromium (Cr), aluminum (Al) or the like, or may be formed by a film forming method other than sputtering. You may form.

  The inter-electrode distance d of the comb electrode 32a and the comb electrode 32b needs to have a value according to the wavelength of the surface acoustic wave excited by the surface acoustic wave element. Assuming that the propagation velocity of the surface acoustic wave is v, the wavelength is λ, and the excitation frequency of the comb electrode is f, there is a relationship of v = f × λ, d = λ / 2. For example, in the case of lithium niobate, when the excitation frequency is 2.45 GHz, the interelectrode distance d needs to be about 0.8 μm.

  It is preferable that the width and distance between the adjacent comb electrodes 32a and 32b be equal. In the above case, the width of each electrode is more preferably about 0.4 μm which is half of the distance d between the electrodes. Since the propagation velocity v differs depending on the material of the surface acoustic wave element substrate 31 which generates the surface acoustic wave, the distance d between the electrodes can be appropriately selected according to the difference between the arbitrary material and the frequency.

  The reflector 33 is formed on the surface of the surface acoustic wave element substrate 31 on which the comb electrodes 32 a and 32 b are formed, and has substantially the same dimensions as the comb electrode 32 a and the comb electrode 32 b. The reflector 33 is formed by sputtering using Cu similarly to the comb electrodes 32a and 32b. However, the reflector 33 may be formed using an electrode material other than Cu, such as Au, Ti, Ni, chromium (Cr), aluminum (Al) or the like, or may be formed by a film forming method other than the sputtering method. May be

  The reflector 33 reflects the surface acoustic wave induced on the surface of the surface acoustic wave element substrate 31 by the high frequency signal applied to the comb electrodes 32a and 32b, and the measurement information is measured again to the outside through the comb electrode 32a and the comb electrode 32b. Is provided to transmit a response signal. The principle of temperature measurement by the surface acoustic wave element will be described later.

  FIG. 3A is a plan view of the wireless temperature sensor 1, and FIG. 3B is a side view of the wireless temperature sensor 1.

  As shown in FIG. 3A, an antenna electrode layer 11 having a size of approximately 20 mm × 20 mm is provided on the upper surface of the wireless temperature sensor 1 of approximately 30 mm × 30 mm, that is, the surface of the lid 10. The external dimension of the wireless temperature sensor 1 is not limited to approximately 30 mm × 30 mm, and may be a size sufficient for mounting an elastic surface element. The external dimensions of the preferred antenna electrode layer 11 vary depending on the dielectric constant of the lid 10, but the dimensions (approximately 20 mm × 20 mm) are suitable dimensions when the dielectric constant of the lid 10 is, for example, about 9.8. However, the dimensions of the antenna electrode layer 11 are not limited to this.

  As shown in FIG. 3 (b), the container 50 of the wireless temperature sensor 1 is composed of a lid 10 and a container body 20. Although the whole thickness of the wireless temperature sensor 1 is approximately 8 mm, it is not limited to this and can be set arbitrarily.

  FIG. 4 is a cross-sectional view of the wireless temperature sensor 1 along the line B-B shown in FIG. In addition, the same code of B-B is attached | subjected to FIG. 1 so that it may be easy to understand the position of a B-B cross section.

  As shown in FIG. 4, the GND electrode layer 13 is provided in the inner layer of the insulating substrate 12, and the GND pattern opening 13w is provided at the center left of the GND electrode layer 13 in order to penetrate the antenna via hole 11h. The external dimension of the GND electrode layer 13 is approximately 25 mm × 25 mm, but is not limited thereto. In order to further improve the high frequency characteristics, the shape of the GND electrode layer 13 is preferably made larger.

  FIG. 5 is a diagram for explaining a temperature detection method by the wireless temperature sensor 1.

  The temperature detection method by the wireless temperature sensor 1 is based on the principle that the propagation velocity of the surface acoustic wave propagating through the surface acoustic wave element substrate 31 depends on temperature. In other words, the dependence of the propagation time of the excitation surface acoustic wave Tw and the reflection surface acoustic wave Rw on the temperature of the surface acoustic wave element substrate 31 is used. Therefore, a calibration table of "propagation time vs. surface acoustic wave element substrate temperature" is prepared in advance.

  First, an external device (not shown) transmits a high frequency signal including an excitation frequency specific to the above-described antenna (a microstrip antenna including the antenna electrode layer 11, the insulating substrate 12, and the GND electrode layer 13). As shown in FIG. 5, a high frequency signal received by the antenna is applied to the comb electrode 32a and the comb electrode 32b through the bonding wires 35a and 35b to bring about an electro-mechanical conversion effect on the surface acoustic wave element substrate 31. That is, on the surface of the surface acoustic wave element substrate 31, an excited surface acoustic wave Tw determined by the inter-electrode distance d of the interdigital transducer is generated.

  The excited surface acoustic wave Tw propagates on the surface of the surface acoustic wave element substrate 31, is reflected by the reflector 33, becomes a reflected surface acoustic wave Rw, and returns again to the comb electrode 32a and the comb electrode 32b. Next, a part of the reflection surface acoustic wave Rw brings about a mechanical-electrical conversion effect to the surface acoustic wave element substrate 31, is converted into a high frequency signal, and the antenna transmits a response signal to the outside. On the other hand, a part of the reflection surface acoustic wave Rw which is not converted into a high frequency signal is reflected by the comb electrode 32 a and the comb electrode 32 b and travels on the surface acoustic wave element 31 again toward the reflector 33. Hereinafter, the reflected surface acoustic wave Rw is gradually converted into a high frequency signal by the comb electrodes 32 a and 32 b while passing between the reflector 33 and the comb electrodes 32 a and 32 b on the surface acoustic wave element substrate 31. While being dampened.

  When the response signal transmitted by the antenna reaches the external device and the external device receives the response signal, the external device measures the time from the transmission of the high frequency signal to the reception of the response signal.

  When the time from transmitting the high frequency signal to receiving the response signal is measured, the propagation time of the surface acoustic wave in the surface acoustic wave element is calculated from the time from transmitting the high frequency signal to receiving the response signal. . Then, the temperature of the surface acoustic wave element substrate 31 is determined from the calculated propagation time based on a calibration table of “propagation time versus surface acoustic wave element substrate temperature” prepared in advance. Then, based on the temperature of the surface acoustic wave element substrate 31, the measurement temperature of the object on which the surface acoustic wave element substrate 31 is mounted is determined.

  FIG. 6 is a graph showing the temporal change of the reflected surface acoustic wave intensity Rwp in the surface acoustic wave element.

  In the graph shown in FIG. 6, the vertical axis represents the intensity Rwp of the reflection surface acoustic wave Rw, and the horizontal axis represents the propagation time T of the surface acoustic wave. The reflection surface acoustic wave Rw is repeatedly reflected between the comb electrode 32a and the comb electrode 32b and the reflector 33. Therefore, the reflection surface acoustic wave Rw is observed at a plurality of timings from time T1 to time T3. The intensity Rwp of the reflected surface acoustic wave Rw is highest at Rw1 at time T1, that is, the intensity of the reflected surface acoustic wave Rw detected first, which is advantageous for measurement.

  FIG. 7 is a diagram for explaining the configuration of a temperature measurement system using the wireless temperature sensor 1.

  The temperature display device 40 transmits a high frequency signal for performing temperature measurement to each of the plurality of wireless temperature sensors, receives a response signal of each wireless temperature sensor, and based on the above calibration table, It is configured to display the measured temperature.

  In the example shown in FIG. 7, the display unit of the measured temperature of the temperature display device 40 is one, and the display unit is detected by a predetermined wireless temperature sensor selected by a switch or the like from among a plurality of wireless temperature sensors. Display temperature. However, separate displays corresponding to each of the plurality of wireless temperature sensors may be provided on the temperature display device 40.

  In the example shown in FIG. 7, three of the wireless temperature sensors 1A to 1C are used, and the surface acoustic wave propagation distances L are designed to be different. Each wireless temperature sensor has its own "propagation time versus surface acoustic wave substrate temperature" table.

  The temperature display device 40 transmits a high frequency signal including an excitation frequency specific to each wireless temperature sensor. A response signal delayed by the propagation time of the surface acoustic wave is generated from each wireless temperature sensor. The wireless temperature sensors 1A to 1C are preferably mounted in close contact with the measurement object so as not to generate a thermal gradient with the measurement object (not shown).

  By changing the surface acoustic wave propagation distance L, each wireless temperature sensor reciprocates the reflector 33 from the comb electrodes 32a and 32b with different propagation times. The wireless temperature sensors 1A to 1C can be distinguished from the difference in propagation time. Further, from this propagation time, the temperature of the measurement object (not shown) can be measured from the calibration table of "propagation time vs. surface acoustic wave element substrate temperature" corresponding to each wireless temperature sensor.

  As described above, the operating frequency of each wireless temperature sensor may be designed to be different, in addition to the method of designing the surface acoustic wave propagation distance L of each wireless temperature sensor to be different. This can be realized, for example, by changing the inter-electrode distance d of the comb electrodes 32a and 32b. By changing the inter-electrode distance d of the comb electrodes, each wireless temperature sensor is excited only by the unique high frequency signal f1 to high frequency signal f3. Therefore, by providing the temperature display device 40 with a frequency sweep function (not shown), the high frequency signal f1 to the high frequency signal f3 can be sequentially transmitted and received, and the temperature of the measurement object (not shown) can be measured.

  The method of using the temperature characteristic of the surface acoustic wave propagation time of the surface acoustic wave element substrate 31 for temperature measurement has been described above. However, the impedance modulation function by temperature is provided to the reflector 33, and the temperature is measured based on the absolute value of the intensity Rwp of the reflection surface acoustic wave, or a resonant circuit is formed of a piezoelectric element or a ferroelectric element Methods using temperature characteristics are also effective.

  FIG. 8 is a flowchart showing an outline of the manufacturing process of the wireless temperature sensor 1.

  As shown in FIG. 8, the manufacturing process of the wireless temperature sensor 1 includes a first structure assembly process ST1, a temperature detection element mounting process ST2, and a container assembly process ST3.

  In the first structure assembling step ST1, a step of preparing the lid 10 which is the first structure including the insulating substrate 12 and the antenna electrode 11 and the GND electrode 13 disposed on the first structure form an antenna. It is a process. The temperature detection element mounting step ST2 is a step of fixing the temperature detection element 30 to the first structure so that the temperature detection element 30 is electrically connected to the antenna electrode 11 and the GND electrode 13. The container assembling step ST3 prepares the container main body 20 which is the second structure, and the first structure and the second structure are arranged such that the second structure is disposed on the side wall 31a side of the temperature detection element 30. It is a process of joining and assembling a structure.

  FIG. 9 is a diagram for explaining a first structure assembling step ST1 of the wireless temperature sensor 1.

  First, as shown in FIG. 9A, a first collective insulating substrate 12b is formed using a ceramic green sheet of LTCC, and a plurality of antenna via holes 11h are provided using Cu.

  Next, as shown in FIG. 9B, as a step of forming an antenna electrode, the first collective insulating substrate 12b manufactured in FIG. It forms by printing and connects each antenna electrode layer 11 and each antenna via hole 11h.

  Next, as shown in FIG. 9C, a second collective insulating substrate 12c is formed using a ceramic green sheet of LTCC. Furthermore, in the second collective insulating substrate 12c, Cu is used in the second collective insulating substrate 12c to form a plurality of antenna via holes 11h for connecting to the antenna electrode layer 11 and a plurality of GND via holes 13h for connecting to the GND electrode layer 13. Form.

  Next, as shown in FIG. 9D, in the step of forming a GND electrode, GND electrode layers 13 which are a plurality of conductor patterns using Cu are formed by printing on the manufactured second collective insulating substrate 12c. A GND pattern opening 13w is provided in a portion of the GND electrode layer 13 that extends over the antenna via hole 11h, and the antenna via hole 11h is formed in the GND pattern opening 13w. Furthermore, each GND electrode layer 13 and each GND via hole 13h are connected.

  Next, as shown in FIG. 9E, the first collective insulating substrate 12b is superimposed on the top of the second collective insulating substrate 12c, and the antenna via holes 11h are connected. Next, an electrode pad forming step is performed in which an antenna connection pad 15a using Cu for each antenna via hole 11h and a GND connection pad 15b using Cu for each GND via hole 13h are formed. Then, it is fired at about 890 ° C. suitable for the first collective insulating substrate 12 b and the second collective insulating substrate 12 c.

  The formation order of the first collective insulating substrate and the second collective insulating substrate may be reversed. That is, after printing is performed with the front and back turned, the second collective insulating substrate 12c may be stacked on the first collective insulating substrate 12b and fired.

  After firing, as shown in FIG. 9F, a collective lid 10b which is a first structural body is obtained. Here, each antenna electrode layer 11, each antenna via hole 11h, and each antenna connection pad 15a are integrally conducted, and each GND electrode layer 13, each GND via hole 13h, and each GND connection pad 15b are integrated. It is conducting. Further, the first collective insulating substrate 12b and the second collective insulating substrate 12c are integrated to form a collective insulating substrate 12a.

  The conductor patterns in the collective cover 10b described above are all made of Cu, but may be made of Ag instead of Cu.

  At the above-described firing temperature (about 890 ° C.), neither Ag nor Cu produces a change that substantially affects the antenna characteristics of the wireless temperature sensor.

  FIG. 10 is a diagram for explaining the temperature detection element mounting step ST2 of the wireless temperature sensor 1. As shown in FIG.

  First, as shown in FIG. 10 (a), a plurality of temperature detection elements 30 are mounted on the lid mounting surface 15m of the collective lid 10b by metal brazing using an alloy of titanium (Ti) and nickel (Ni) Do. In addition, the metal used for a metal brazing method is not limited to these, You may use the combination of another metal.

  Next, as shown in FIG. 10B, the element bonding pads 34a of the temperature detection elements 30 and the antenna connection pads 15a of the collective lid 10b are connected by the bonding wires 35a. Similarly, the element bonding pad 34b of each temperature detection element 30 and the GND connection pad 15b of the collective lid 10b are connected by the bonding wire 35b.

  FIG. 10C is a cross-sectional view showing another method of joining the temperature detection element 30 to the collective lid 10b. As shown in FIG. 10C, gold bumps 36a and 36b are provided on the mounting surface of the temperature detection element 30f.

  More specifically, the element bonding pad 34a is connected to the gold bump 36a on the mounting surface, and the element bonding pad 34b is connected to the gold bump 36b on the mounting surface by via holes (not shown) provided inside the temperature detection element 30f. The gold bump 36a is welded to the antenna connection pad 15a on the mounting surface 15m, and the gold bump 36b is welded to the GND connection pad 15b on the mounting surface 15m by ultrasonic or pressure. The manufacturing process by these other methods, and the product thereof are also included in the technical scope of the present invention.

  FIG. 10D is a cross-sectional view showing still another method of bonding the temperature detection element 30 to the collective lid 10b. The surface of the temperature detection element 30 on which the element bonding pads 34a and 34b are formed is opposed to the collective lid 10b. The temperature detection element 30 is flipped to the collective lid 10b such that the element bonding pad 34a is connected to the antenna connection pad 15a by the gold bump 36a and the element bonding pad 34b is connected to the antenna connection pad 15b by the gold bump 36b. It is chip mounted. The configuration of the flip chip mounting will be described later.

  FIG. 11 is a view for explaining a container assembling step ST3 of the wireless temperature sensor 1.

  First, as shown in FIG. 11A, the ceramic material, the glass filler, the binder, the solvent, and the like are mixed and stirred, and the ceramic green sheet of HTCC prepared is used to form the main body bottom collecting substrate 21b.

  Next, as shown in FIG. 11 (b), a main body side aggregate substrate 22b is formed using a ceramic green sheet of HTCC, and a plurality of main body cavities 20c are provided in the main body side aggregate substrate 22b.

  Next, as shown in FIG. 11C, the main body bottom collective substrate 21b and the main body side collective substrate 22b are stacked and baked at a high temperature of about 1610 ° C. After firing, a collective container body 20b shown in FIG. 11 (d) is obtained.

  Next, as shown in FIGS. 11E and 11F, the collecting container main body 20b and the collecting lid 10b on which the temperature detecting element 30 is mounted are placed so that the main body cavity 20c is aligned with the position of the temperature detecting element 30. Overlap and bonding to obtain an integrated wireless temperature sensor 1b. Thereby, the collection container main body 20b which is a 2nd structure on the side wall 31a side of the temperature detection element 30 is arrange | positioned.

  The collecting container main body 20b and the collecting lid 10b form, for example, gold (Au) and tin (Sn) on the bonding surface and perform eutectic bonding. Since Au and Sn have high thermal conductivity, the collecting container main body 20b and the collecting lid 10b are thermally connected. Thus, the heat obtained by the collecting container main body 20b (container main body 20) can be transmitted to the respective temperature detection elements 30 through the collecting lid 10b (lid 10). In addition, the material and joining method for joining the collecting container main body 20b and the collecting lid 10b are not limited to the above, and metal brazing method, solid phase bonding method for pressure fusing between materials under high temperature, etc. Other bonding methods can also be used.

  As shown in FIG. 11 (f), the assembled collective wireless temperature sensor 1b is divided along the cutting line dc to obtain the singulated wireless temperature sensor 1 shown in FIG. 11 (g). Although the above example describes the method of manufacturing three wireless temperature sensors at one time, it is also possible to further increase the number of wireless temperature sensors manufactured at one time.

  In the wireless temperature sensor 1, the temperature detection element 30 is mounted on an antenna (lid 10) formed by laminating the antenna electrode layer 11 and the GND electrode layer 13 on the insulating substrate 12. Therefore, it is possible to provide a wireless temperature sensor that is easy to manufacture and has improved reliability.

  FIG. 12 is a diagram for explaining the structure of another wireless temperature sensor 2.

  The wireless temperature sensor 2 is a modification of the wireless temperature sensor 1 described above. In the following, the points of the wireless temperature sensor 2 different from the wireless temperature sensor 1 will be described, and the points similar to the wireless temperature sensor 1 will not be described as appropriate.

  The difference between the wireless temperature sensor 2 shown in FIG. 12 and the wireless temperature sensor 1 shown in FIG. 1 is the presence or absence of the heat conduction layer provided on the insulating substrate, and the other points are the same.

  As shown in FIG. 12, the wireless temperature sensor 2 further includes a heat conduction layer 17 provided below the insulating substrate 12. The heat conduction layer 17 has dimensions of approximately 25 mm × 25 mm, and is thermally connected to the container body 20 at the end. At the formation position of the antenna connection pad 15 a of the heat conduction layer 17, a heat conduction layer opening 17 w is provided. However, the shape and size of the heat conduction layer 17 can be arbitrarily designed as long as they can be thermally connected to the container body 20.

  The heat conduction layer 17 is formed using Cu, but other metals may be used. The heat conduction layer 17 is electrically connected to the GND connection pad 15b. The heat conduction layer 17 and the GND connection pad 15b may be integrally formed of the same material. In FIG. 12, the heat conduction layer 17 may be electrically connected to the antenna connection pad 15 a instead of the GND connection pad 15 b.

  The temperature detection element 30 is metal brazed on the heat conduction layer 17. The element bonding pad 34 a of the temperature detection element 30 is electrically connected to the antenna connection pad 15 a via the bonding wire 35 a. The element bonding pad 34b of the temperature detection element 30 is electrically connected to the GND connection pad 15b (or the heat conduction layer 17) through the bonding wire 35b.

  The first structure assembly process of the wireless temperature sensor 2 will be described with reference to FIG. The other steps (the temperature detection element mounting step and the container assembling step) of the method of manufacturing the wireless temperature sensor 2 are the same as those of the wireless temperature sensor 1 and thus the description thereof is omitted.

  First, as shown in FIG. 13A, the first collective insulating substrate 12b is formed. The formation of the first collective insulating substrate 12 b is the same as that of the wireless temperature sensor 1, so the description will be omitted.

  Next, as shown in FIG. 13B, a plurality of antenna connection pads 15a and GND connection pads 15b (thermal conductive layers 17) are formed using Cu. Each heat conduction layer 17 is provided with a heat conduction layer opening 17 w.

  Next, as shown in FIG. 13C, the antenna connection pad 15a and the GND connection pad 15b (heat conduction shown in FIG. 13B) are formed on the ceramic green sheet of the LTCC in which the antenna via hole 11h and the GND via hole 13h are formed. Apply layer 17). At this time, the heat conduction layer opening 17 w is attached so as to fit the position of the antenna via hole 11 h. Furthermore, the antenna connection pad 15a and the GND connection pad 15b (the heat conductive layer 17) are connected to the antenna via hole 11h and the GND via hole 13h, respectively, to obtain the second collective insulating substrate 12d.

  Next, as shown in FIG. 13D, the GND electrode layer 13 is printed and formed on the second collective insulating substrate 12d using Cu, and the GND electrode layer 13 is connected to the GND via hole 13h. A GND pattern opening 13 w is provided in the GND electrode layer 13, and an antenna via hole 11 h is formed in the GND pattern opening 13 w.

  Next, as shown in FIG. 13 (e), the first collective insulating substrate 12b is superimposed on the second collective insulating substrate 12d shown in FIG. 13 (d), and the antenna via hole 11h and the GND via hole 13h are connected respectively. Do. Further, this is baked at about 890 ° C. to obtain a collective lid 10Ab shown in FIG. 13 (f).

  The wireless temperature sensor 2 has a heat conduction layer 17 provided below the insulating substrate 12, and the heat conduction layer 17 is thermally connected to each of the container body 20 and the temperature detection element 30. Therefore, the heat of the measurement object transmitted to the container body 20 can be transmitted from the container body 20 to the temperature detection element 30 via the heat conduction layer 17. Therefore, heat is prevented from being dissipated in the lid 10A, and the thermal responsiveness as the wireless temperature sensor 2 is further improved.

  In the wireless temperature sensor 2, since the temperature detection element 30 is connected to the GND connection pad 15b, noise resistance is improved, and the characteristics and reliability as a temperature sensor are improved.

  FIG. 14 is a diagram for explaining the structure of still another wireless temperature sensor 3.

  The wireless temperature sensor 3 is a modification of the wireless temperature sensor 2 described above. In the following, the points of the wireless temperature sensor 3 that are different from the wireless temperature sensor 2 will be described, and the points similar to the wireless temperature sensor 2 will not be described as appropriate.

  The difference between the wireless temperature sensor 3 shown in FIG. 14 and the wireless temperature sensor 2 shown in FIG. 12 is the point of the position of the GND via hole, and the others are similar.

  As shown in FIG. 14, in the wireless temperature sensor 3, the temperature detection element 30 is fixed on the GND via hole 13h. Here, "fixed on the GND via hole 13h" includes the case where the substantially central position of the temperature detection element 30 is equal to the substantially central position of the GND via hole 13h, as shown in FIG. Not limited to this. For example, the case where the substantially central position of the GND via hole 13 h is included in the area of the temperature detection element 30 or the case where the area of the GND via hole 13 h is included in the area of the temperature detection element 30 is included.

  The position of the GND via hole 13h is not limited to the vicinity of the approximate center of the lid 10A, and can be arbitrarily disposed. The temperature detection element 30 can be “fixed on the GND via hole 13 h” in accordance with the position of the GND via hole 13 h.

  FIG. 15A is a cross-sectional view schematically showing a propagation path of heat from a measurement object (not shown) of the wireless temperature sensor 2. FIG. 15B is a cross-sectional view schematically showing the propagation path of heat from the measurement object (not shown) of the wireless temperature sensor 3. In FIGS. 15 (a) and 15 (b), hatching representing a cross section is omitted for the sake of explanation.

  As shown in FIG. 15A, in the wireless temperature sensor 2, as indicated by H, the heat transferred from the measuring object (not shown) to the container body 20 moves inside the container body 20, and eventually the heat conduction layer 17 It is transmitted to. The heat transferred to the heat conduction layer 17 moves inside the heat conduction layer 17 toward the temperature detection element 30, but a part of the heat moves to the insulating substrate 12 through the GND via hole 13h as shown by H1. Do. This is because the thermal resistance of the GND via hole 13 h formed of Cu is low.

  As shown in FIG. 15 (b), in the wireless temperature sensor 3, as shown by H, the heat transferred from the measuring object (not shown) to the container body 20 moves inside the container body 20, and eventually the heat conduction layer 17 It is transmitted to. The heat transferred to the heat conduction layer 17 moves toward the temperature detection element 30 inside the heat conduction layer 17 as indicated by H2. At this time, since there is no GND via hole 13 h having a low thermal resistance in the middle of the route to the temperature detection element 30, most of the heat flows into the temperature detection element 30 via the heat conduction layer 17.

  As described above, in the wireless temperature sensor 3, since the temperature detection element 30 is fixed on the GND via hole 13h, the amount of heat transferred to the inside of the lid 10 can be reduced by the via hole. Therefore, in the wireless temperature sensor 3, the responsiveness of temperature measurement is improved, and the variation of the antenna characteristic due to the influence of heat is reduced.

  FIG. 16 is a diagram for explaining the structure of still another wireless temperature sensor 4.

  The wireless temperature sensor 4 is a modification of the wireless temperature sensor 1 described above. In the following, the points of the wireless temperature sensor 4 different from the wireless temperature sensor 1 will be described, and the points similar to the wireless temperature sensor 1 will not be described as appropriate.

  The difference between the wireless temperature sensor 4 shown in FIG. 16 and the wireless temperature sensor 1 shown in FIG. 1 is the shape of the first structure and the second structure, and the other is the same.

  As shown in FIG. 16, the insulating substrate 12 of the container body 10B which is the first structure of the wireless temperature sensor 4 has a container shape provided with the container body side 23s, and the lid which is the second structure 25 forms a lid shape.

  A method of manufacturing the wireless temperature sensor 4 will be described with reference to FIG. In addition, about the process similar to the wireless temperature sensor 1, description is abbreviate | omitted suitably.

  First, as shown in FIG. 17A, the first collective insulating substrate 12b and the second collective insulating substrate 12c are formed, and the first collective insulating substrate 12b is superimposed on the second collective insulating substrate 12c. . In addition, since the said process is the same as the process demonstrated using FIG. 8 (a)-(e), description is abbreviate | omitted.

  Next, as shown in FIG. 17B, a third collective insulating substrate 12e is formed using a ceramic green sheet of LTCC, and a plurality of main cavities 20c are provided in the third collective insulating substrate 12e.

  Next, as shown in FIG. 17C, the third collective insulating substrate 12e, the first collective insulating substrate 12b, and the second collective insulating substrate 12c are stacked and fired at about 890.degree. By firing, a collection container main body 10Bb in which the first collective insulating substrate 12b, the second collective insulating substrate 12c, and the third collective insulating substrate 12e are integrated as shown in FIG. 17D is obtained.

  Next, as shown in FIG. 17E, the temperature detection element 30 is mounted in each main body cavity 20c of the collection container main body 10Bb, and the antenna connection pad 15a and the GND connection pad 15b are formed by the bonding wire 35a and the bonding wire 35b. Each is connected to complete the assembly of the collecting container body 10Bb.

  Next, as shown in FIG. 17F, a ceramic green sheet of HTCC material is used to form a main body bottom collective substrate 25c, and the main body bottom collective substrate 25c and the collective container main body 10Bb are made of Au or Sn. The eutectic bonding is performed to form a collective wireless temperature sensor 4b. Furthermore, the collective wireless temperature sensor 4b is singulated along a cutting line dc indicated by a dashed dotted line. A perspective view of the singulated wireless temperature sensor 4 is shown in the lower part of FIG.

  In the wireless temperature sensor 4, the material can be selected more widely by forming the first structure in a container shape and the second structure in a lid shape, that is, a plate shape. For example, when the wireless temperature sensor of the present invention is used for temperature measurement with higher accuracy, a thin metal plate as the lid 25 (an oxide film may be provided on the surface if necessary, and an insulating substrate may be used) It is possible to improve the quality. Further, by forming the lid 25 of a polymer material and adhering the lid 25 to the container body 10B, it is possible to reduce the number of firing steps and to improve production efficiency.

  FIG. 18 is a diagram for describing the structure of still another wireless temperature sensor 5.

  The wireless temperature sensor 5 is a modification of the wireless temperature sensor 1 described above. In the following, the points of the wireless temperature sensor 5 that are different from the wireless temperature sensor 1 will be described, and the same points as the wireless temperature sensor 5 will not be described as appropriate.

  The difference between the wireless temperature sensor 5 shown in FIG. 18 and the wireless temperature sensor 1 shown in FIG. 1 is in the mounting method of the temperature detection element and in the contact between the temperature detection element and the container body. It is.

  As shown in FIG. 18, the temperature detection element 30 is flip-chip mounted on the lid 10 with the surface provided with the comb electrodes 32 a and 32 b and the reflector 33 facing the lid 10. The element bonding pad 34a is connected to the antenna connection pad 15a via the gold bump 36a, and the element bonding pad 34b is connected to the GND connection pad 15b via the gold bump 36b.

  As shown in FIG. 18, in the wireless temperature sensor 5, the surface of the temperature detection element 30 opposite to the surface facing the lid 10 is in contact with the container body 20. However, even if the temperature detection element 30 and the container body 20 are not in contact with each other, they may be in close proximity to each other to such an extent that direct heat conduction occurs between them. The position of the temperature detection element 30 in contact with or in proximity to the container body 20, and in the case of proximity, the distance between the temperature detection element 30 and the container body 20 is arbitrarily designed as long as direct heat conduction occurs between them. can do.

  Hereinafter, the temperature detection element mounting process of the wireless temperature sensor 5 will be described with reference to FIG. In addition, since the other processes (a 1st structure assembly national determination and a container assembly process) of the manufacturing method of the wireless temperature sensor 5 are the same as that of the wireless temperature sensor 1, description is abbreviate | omitted. The thickness of the space inside the container main body 20 is set to a length corresponding to the height from the mounting surface 15 m to the surface of the temperature detection element 30 opposite to the lid 10. Although the manufacturing process of one wireless temperature sensor is described below for convenience of explanation, it is also possible to use a manufacturing method in which a plurality of wireless temperature sensors are simultaneously created and then singulated.

  First, as shown in FIG. 19A, gold bumps 36a are formed on the element bonding pads 34a of the temperature detection element 30, and gold bumps 36b are formed on the element bonding pads 34b of the temperature detection element 30, respectively.

  Next, as shown in FIG. 19B, the temperature detection element 30 is inverted so that the gold bumps 36a contact the antenna connection pads 15a and the gold bumps 36b contact the GND connection pads 15b, respectively. The element 30 is placed on the lid mounting surface 15 m.

  Next, as shown in FIG. 19C, the temperature detection element 30 is formed by fusing and bonding the bonding pads (15a, 15b, 34a, 34b) and the gold bumps 36a, 36b by ultrasonic vibration. On the lid 10. Above, the temperature detection element mounting process in the wireless temperature sensor 5 is completed.

  In the wireless temperature sensor 5, the temperature detection element 30 and the container body 20 are in contact with each other or in close proximity to each other to such an extent that direct heat conduction occurs between the two. Therefore, the heat transferred from the object to be measured to the container body 20 can be directly transferred from the container body 20 to the temperature detection element 30 as shown by H3 in FIG. Therefore, the responsiveness of the temperature measurement in the wireless temperature sensor is improved.

  FIG. 20 is a view for explaining the structure of still another wireless temperature sensor 6, and FIG. 21 is a view of the wireless temperature sensor 6 as viewed from the direction 6D of FIG.

  The wireless temperature sensor 6 is a modification of the wireless temperature sensor 5 described above. In the following, the points of the wireless temperature sensor 6 that are different from the wireless temperature sensor 5 will be described, and the points that are the same as the wireless temperature sensor 5 will not be described as appropriate.

  The difference between the wireless temperature sensor 6 shown in FIG. 20 and the wireless temperature sensor 5 shown in FIG. 18 is the presence or absence of an opening provided on the side opposite to the side to be joined to the lid of the container body It is.

  The container body 20 </ b> A of the wireless temperature sensor 6 has an opening 20 </ b> AW on the opposite side to the surface facing the lid 10. Therefore, as shown in FIG. 21, the temperature detection element 30 is exposed to the outside.

  The shape of the opening 20AW is not limited to a rectangular shape, and may be any shape such as a circle, a polygon, or an irregular shape. The container main body 20A can be obtained, for example, by preparing a container main body without using the main body bottom collecting substrate 21b described with reference to FIG. 11 (a), but can be prepared by other methods. .

  A sealing resin 70 is provided at the edge of the temperature detection element 30 so as to fill the space between the temperature detection element 30 and the lid 10, and airtight sealing is performed by the lid 10, the temperature detection element 30, and the sealing resin 70. Space 6S is formed. The space 6S includes the comb electrodes 32a and 32b and the reflector 33 therein.

  In the wireless temperature sensor 6, the opening 20AW is provided on the side opposite to the side of the container body 20A joined to the lid 10, and the temperature detection element 30 is exposed to the outside. It becomes possible to arrange near the measurement object. Therefore, the heat of the object to be measured is easily transmitted to the temperature detection element 30, and the thermal responsiveness of the wireless temperature sensor is improved.

  In the wireless temperature sensor 6, since the comb electrodes 32a and 32b and the reflector 33 are included in the space 6S hermetically sealed by the sealing resin 70, the external gas or fluid can not enter the space 6S. Therefore, the stability of the antenna characteristic of the wireless temperature sensor is improved. The space 6S may be a vacuum, and when the space 6S is a vacuum, the stability of the antenna characteristic of the wireless temperature sensor is further improved.

  FIG. 22 is a view for explaining the structure of still another wireless temperature sensor 7, and FIG. 23 is a view of the wireless temperature sensor 7 as viewed from the direction 7D of FIG.

  The wireless temperature sensor 7 is a modified example of the wireless temperature sensor 6 described above. In the following, the points of the wireless temperature sensor 7 which are different from the wireless temperature sensor 6 will be described, and the points similar to the wireless temperature sensor 6 will not be described as appropriate.

  As shown in FIG. 22, the wireless temperature sensor 7 does not have the container body 20A itself, and instead, the sealing resin 71 serves as a second structure. The sealing resin 71 is formed so as to cover the side wall 31 a of the temperature detection element 30, and is disposed on the side wall 31 a side of the temperature detection element 30.

  Since the wireless temperature sensor 7 does not have a container body, it becomes easy to attach the temperature detection element 30 directly to the object to be measured, and the thermal responsiveness of the wireless temperature sensor is further improved.

  FIG. 24 is a diagram for explaining the structure of still another wireless temperature sensor 8.

  The wireless temperature sensor 8 is a modified example of the wireless temperature sensor 5 described above. In the following, the points of the wireless temperature sensor 8 that are different from the wireless temperature sensor 5 will be described, and the points similar to the wireless temperature sensor 5 will not be described as appropriate.

  The difference between the wireless temperature sensor 8 shown in FIG. 24 and the wireless temperature sensor 5 shown in FIG. 18 is the presence or absence of a heat conductor, and the other points are the same.

  As shown in FIG. 24, the wireless temperature sensor 8 further includes a heat conductor 60 disposed between the temperature detection element 30 and the container body 20. The heat conductor 60 is thermally connected to both of the temperature detection element 30 and the container main body 20, and is bonded, for example, by a high thermal conductivity resin. Alternatively, the heat conductor 60 may not be bonded to the temperature detection element 30 and the container main body 20, or may be sandwiched by these.

  The heat conductor 60 is formed of silver paste having high thermal conductivity. However, the heat conductor 60 may be formed of a material having high thermal conductivity, such as epoxy resin, silicon resin, ceramic material, metal, and heat resistant resin, as well as silver paste.

  Furthermore, the heat conductor 60 preferably has a low coefficient of thermal expansion in order to maintain the airtightness of the lid 10 and the container body 20.

  Hereinafter, the temperature detection element mounting and the whole assembly process of the wireless temperature sensor 8 will be described with reference to FIG. In addition, since the 1st structure assembly process of the wireless temperature sensor 8 is the same as that of the wireless temperature sensor 1, description is abbreviate | omitted.

  First, as shown in FIG. 25A, the temperature detection element 30 is flip-chip mounted on the lid 10. In addition, since the said process is the same as the process mentioned above using Fig.19 (a)-(d), description is abbreviate | omitted.

  Next, as shown in FIG. 25B, a heat conductor 60 which is a silver paste formed by firing a mixture of silver particles mixed in a binder on the surface of the temperature detection element 30 opposite to the lid 10. Are bonded using a high thermal conductivity resin.

  Next, as shown in FIG. 25C, the container body 20 is overlapped and joined to the lid 10 on which the temperature detection element 30 is mounted so that the body cavity 20c is aligned with the position of the temperature detection element 30. The wireless temperature sensor 8 shown in FIG. The bonding method is the same as the method described above with reference to FIGS. 11 (e) and (f), so the description will be omitted.

  Note that, unlike the above-described method, after adhering the heat conductor 60 to the bottom of the container body 20, the lid 10 and the container body 20 are overlapped and joined so that the heat conductor 60 contacts the temperature detection element 30, A wireless temperature sensor 8 may be obtained.

  In the wireless temperature sensor 8, since the heat conductor 60 is disposed between the temperature detection element 30 and the container body 20, the heat of the measurement object transmitted to the container body 20 is detected via the heat conductor 60. It is transmitted to the element 30. Therefore, the heat of the object to be measured is easily transmitted to the temperature detection element 30, and the thermal responsiveness of the wireless temperature sensor is improved.

  FIG. 26 is a diagram for explaining the structure of still another wireless temperature sensor 9.

  The wireless temperature sensor 9 is a modified example of the wireless temperature sensor 5 described above. In the following, the points of the wireless temperature sensor 9 which are different from the wireless temperature sensor 5 will be described, and the points similar to the wireless temperature sensor 5 will not be described as appropriate.

  The difference between the wireless temperature sensor 9 shown in FIG. 26 and the wireless temperature sensor 5 shown in FIG. 17 is the structure of the container body, and the other is the same.

Similar to the container body 20 of the wireless temperature sensor 1, the container body 20 B of the wireless temperature sensor 9 is formed of Al ₂ O ₃ which is a HTCC. However, unlike the container body 20, the container body 20B has a porous (porous) structure which is a structure capable of passing gas or fluid. For example, when the container body 20B is formed of metal, a mesh structure may be employed as a structure through which gas or fluid can pass. Thus, as the structure of the container body 20B, a structure capable of passing gas or fluid can be designed according to the substance forming the container body 20B.

  A sealing resin 70 is provided at the edge of the temperature detection element 30 of the wireless temperature sensor 9 so as to fill the space between the temperature detection element 30 and the lid 10, and the lid 10, the temperature detection element 30, and the sealing resin A space 9S hermetically sealed by 70 is formed. The space 9S contains the comb electrodes 32a and 32b and the reflector 33 therein.

  The wireless temperature sensor 9 has a structure in which the container body 20B allows gas or fluid to pass therethrough. Therefore, as indicated by H4 in FIG. 26, the gas or fluid around the wireless temperature sensor 9 passes through the container body 20B and enters and exits the space (except the space 9S) enclosed by the lid 10 and the container body 20B. It is possible to Therefore, since the temperature detection element 30 can directly detect the temperature of the gas or fluid, the wireless temperature sensor 9 can measure the ambient temperature (ambient temperature) more accurately.

  In the wireless temperature sensor 9, the comb electrodes 32 a and 32 b and the reflector 33 are included in the space 9 S hermetically sealed by the sealing resin 70. Therefore, the gas or fluid which passes through the container body 20B and flows into the space surrounded by the lid 10 and the container body 20B can not enter the space 9S. Therefore, the stability of the antenna characteristic of the wireless temperature sensor is improved. The space 9S may be a vacuum, and when the space 9S is a vacuum, the stability of the antenna characteristic of the wireless temperature sensor is further improved.

  The wireless temperature sensors 1-9 described above are applicable to devices requiring remote sensing of temperature measurement.

  It is to be understood that those skilled in the art can add various changes, substitutions, and alterations thereto without departing from the spirit and scope of the present invention, and that the embodiments may be combined as appropriate.

1, 1A-1C, 2, 3, 4, 5, 6, 7, 8, 9 Wireless Temperature Sensor 1b Collective Wireless Temperature Sensor 10, 10A, 25 Lid 10b, 10Ab, 10Bb Collective Lid 11 Antenna Electrode 11h Antenna Via Hole 12 Insulation Substrate 12b First collective insulating substrate 12c, 12d Second collective insulating substrate 12e Third collective insulating substrate 13 GND electrode 13h GND via hole 13w GND pattern opening 15a Antenna connection pad 15b GND connection pad 15m, 15ma Lid mounting surface 17 Heat conduction layer 17w Heat conduction layer opening 20, 10B Container body 20b Assembly container body 20c Body cavity 21b, 25c Body bottom assembly substrate 22b Body side assembly substrate 23s Container body side 30, 30f Temperature detection element 31 Surface acoustic wave element Substrate 31a Sidewall 32 , 32b Comb electrode 33 Reflector 34a, 34b Element bonding pad 35 Bonding wire 36a, 36b Gold bump 40 Temperature display device 50, 50A, 50B, 50C, 50D Container 70, 71 Sealing resin 101, 121 Container body 107, 125 Lid 104, 123 diaphragm 130 groove 102, 103, 122 external terminal 105, 106, 124, 128 lead 108, 126 coil Tw excitation surface acoustic wave Rw reflection surface acoustic wave Rwp (of reflection surface acoustic wave) intensity T, T1, T2, T3 time d, d1, d2, d3 Inter-electrode distance f1, f2, f3 High frequency signal t Propagation time ST1 First structure assembly process ST2 Temperature detection element mounting process ST3 Container assembly process dc Cutting line

Claims (15)

Providing a first structure and a second structure including an insulating substrate;
Arranging an antenna electrode and a GND electrode on the first structure including the insulating substrate to form an antenna;
A pair of element bonding pads disposed in a temperature detection element that operates according to a signal received by the antenna and outputs a response signal to the antenna are electrically connected to the antenna electrode and the GND electrode, and Fixing a temperature detection element to the first structure;
Bonding and assembling the first structure and the second structure such that a second structure is disposed on a side wall of the temperature detection element;
A method of manufacturing a wireless temperature sensor, comprising:   In the step of joining and assembling the first structure and the second structure, the first structure and the step are further arranged such that the temperature detection element is in contact with the inside of the second structure. The method for manufacturing a wireless temperature sensor according to claim 1, comprising joining and assembling a second structure.   The method for manufacturing a wireless temperature sensor according to claim 1, wherein the second structure has an opening opposite to a side to be bonded to the first structure.   The step of joining and assembling the first structure and the second structure further includes disposing the heat conductor between the second structure and the temperature detection element. The method for manufacturing a wireless temperature sensor according to claim 1, comprising joining and assembling the second structure and the second structure.   The method for manufacturing a wireless temperature sensor according to claim 1, wherein the second structure has a porous structure or a mesh structure. The step of forming the antenna further comprises:
A conductor pattern to be the antenna electrode is disposed on one surface of the insulating substrate,
Arranging a conductor pattern to be the GND electrode in an inner layer of the insulating substrate;
In the insulating substrate, a first via hole electrically connected to the antenna electrode and a second via hole electrically connected to the GND electrode are formed.
The method according to claim 1, further comprising forming a first electrode pad electrically connected to the first via hole and a second electrode pad electrically connected to the second via hole on the other surface of the insulating substrate. A method of manufacturing a wireless temperature sensor according to any one of the preceding claims.   The step of forming the antenna further includes conduction with the second electrode pad and thermal connection to the temperature detection element and the second structure on the other surface of the insulating substrate. The method of claim 6, comprising forming a thermally conductive layer.   8. The method according to claim 7, wherein the step of fixing the temperature detection element to the first structure further includes fixing the temperature detection element on the second via hole on the heat conduction layer. Method of wireless temperature sensor. A first structure having an antenna in which an antenna electrode and a GND electrode are disposed on an insulating substrate;
A temperature detection element fixed on the back side with the surface on which the antenna electrode of the first structure is disposed , operating according to a signal received by the antenna, and outputting a response signal to the antenna ;
And a second structure disposed on the side wall of the temperature detection element and joined to the first structure.
The temperature detection element is fixed to the first structure so that a pair of element bonding pads disposed in the temperature detection element are electrically connected to the antenna electrode and the GND electrode, respectively. Wireless temperature sensor characterized by   The wireless temperature sensor according to claim 9, wherein the temperature detection element is fixed to be in contact with the inside of the second structure.   10. The wireless temperature sensor according to claim 9, wherein the second structure has an opening opposite to a side joined to the first structure.   10. The wireless temperature sensor of claim 9, further comprising a thermal conductor disposed between the second structure and the temperature sensing element.   The wireless temperature sensor according to claim 9, wherein the second structure has a porous structure or a mesh structure.   The wireless temperature sensor according to any one of claims 9 to 13, further comprising a thermally conductive layer formed on the insulating substrate and thermally connected to the temperature detection element and the second structure. The semiconductor device further includes a via hole formed in the insulating substrate and electrically connected to the GND electrode and the heat conduction layer.
The wireless temperature sensor according to claim 14, wherein the temperature detection element is fixed above the via hole on the heat conduction layer.

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