JP2009053100A - Mems module and method for stabilizing characteristic of same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an MEMS module capable of improving the temperature characteristic of its MEMS device without increasing the size of a circuit board and the MEMS module, and a method for stabilizing the characteristic of the MEMS module. <P>SOLUTION: The MEMS module 100 has the MEMS device 112, and a sealing container 102, 104 which seals and accommodates the MEMS device 112 in a specific atmosphere. In the sealing container 102, 104, at least a part of a temperature regulating means 166 for keeping the MEMS device 112 at a constant temperature higher than its ambient temperature, is accommodated. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a MEMS device sealed in a sealed container in a specific atmosphere (hereinafter referred to as a MEMS module) and a method for stabilizing the characteristics of a MEMS module, and more particularly, stabilization of characteristics of a MEMS device having temperature characteristics. It is related with the MEMS module which has a temperature control means suitable for, and the characteristic stabilization method of a MEMS module.

  MEMS (Micro Electro Mechanical Systems) devices (generally manufactured by applying semiconductor microfabrication technology, for example, microdevices having a microstructure that combines mechanical, electronic, optical, chemical, and other complex functions on a silicon wafer. (Typically, there are a pressure sensor, a temperature sensor, an acceleration sensor, an angular acceleration sensor, and the like), and a part for sensing and driving a physical quantity is small. For example, the shape gaps of the capacitance detection sensor and the electrostatic actuator described in Patent Document 1 are only about several to several tens of μm. For this reason, deformation accompanying thermal expansion / contraction due to a change in ambient temperature greatly affects the characteristics of the sensor or actuator.

  In order to improve such temperature characteristics, a temperature compensation function has been provided by using an IC or a discrete circuit.

  Further, in Patent Document 2, although not intended to improve the temperature characteristics, a heater is formed in the sensor, and the presence or absence of a sensor failure can be determined using the temperature dependence of the capacitance measured by the sensor. Proposed.

JP 2007-187494 A JP 2007-86002 A

  However, the temperature compensation function has the following problems.

  (1) When a new IC is generated for the temperature compensation function, a huge amount of cost is required for designing and manufacturing.

  (2) When a discrete circuit is mounted instead of causing an IC, the circuit board for temperature compensation is increased by that amount.

  (3) Correction is difficult in a temperature region where the temperature characteristics deviate from the linearity.

  In addition, in order to improve temperature characteristics, there are devices in which the device itself is placed in a small thermostat, but the size of the module is increased by the thermostat. For example, in the case of a crystal transmitter manufactured by Epson Toyocom, a standard transmitter having a transmission frequency of about 10 to 40 MHz is a minimum of 2.5 mm × 2.0 mm × t 0.8 mm (SG-210 series), At most, it is about 5.0mm x 3.2mm x t1.0mm (TCO-710x series), whereas the transmitter with constant temperature bath TCO-6602 is 27.2mm x 36.2mm x t20mm and SG-210 series. Therefore, there is a problem that the volume becomes about 5,000 times larger.

  Note that Patent Document 2 is merely for determining the presence or absence of a failure, and is not applicable to the characteristic stabilization of the present invention because the technical idea is different from the characteristic stabilization of the present invention. Conceivable.

  The present invention has been made to solve the above-described conventional problems. A MEMS module for improving temperature characteristics of a MEMS device and a method for stabilizing the characteristics of the MEMS module without increasing the size of the circuit board and the MEMS module. It is an issue to provide.

  The invention according to claim 1 of the present application is a MEMS module including a MEMS device and a sealed container that seals and stores the MEMS device in a specific atmosphere. In the sealed container, the MEMS device is placed above ambient temperature. By accommodating at least a part of the temperature adjusting means for maintaining a high and constant temperature, the above problem is solved.

  That is, as shown in FIG. 1, the heater 168 and the MEMS device 112, which are part of the temperature control means, are placed in a sealed container (for example, a hollow structure) in a specific atmosphere (a space replaced with a vacuum or an inert gas). The temperature of the MEMS device 112 can be minimized by stabilizing the temperature inside the sealed container by heating and sealing with the heater 168.

  The invention according to claim 2 of the present application is such that at least a part of the temperature adjusting means is formed in the MEMS device.

  The invention according to claim 3 of the present application is such that the temperature adjusting means includes a heater, a temperature sensor, and a processing circuit for processing a signal of the temperature sensor.

  In the invention according to claim 4 of the present application, the MEMS device is sealed in a sealed container having a specific atmosphere, and at least a part of the MEMS device is set to a constant temperature higher than the ambient temperature of the sealed container. It is intended to provide a method for stabilizing the characteristics of a MEMS module characterized in that it is maintained.

  According to the present invention, it is possible to improve the temperature characteristics of the MEMS device without increasing the size of the circuit board and the MEMS module.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<First Embodiment>
A first embodiment according to the present invention will be described with reference to FIGS. 2 is a schematic cross-sectional view of the MEMS module according to the present embodiment, FIG. 3 is a schematic cross-sectional view of the MEMS device, FIG. 4 is an exploded perspective view of the MEMS device, and FIG. 5 is an outline of a circuit block for temperature control. 6 is a schematic diagram of an example of circuit arrangement on the upper surface of the MEMS device, FIG. 7 is a schematic diagram of the shape of a thin film resistor, and FIG. 8 is a schematic cross-sectional view of a MEMS module according to a modification of the present embodiment. Yes.

  First, the configuration of the present embodiment will be described in detail with reference to FIGS.

  As shown in FIG. 2, the MEMS module 100 includes a lid 102, a container 104, and a MEMS device 112. In this embodiment, the MEMS device 112 is vacuum-sealed in order to reduce the influence of air molecules on the MEMS device 112. The sealed container is composed of the lid 102 and the container 104. Hereinafter, each element will be described.

  The lid 102 is, for example, approximately the same size as the bottom area of the container 104 and, for example, the same material as the container 104 is used in order to match the coefficient of thermal expansion.

The container 104 is a ceramic container mainly composed of alumina (Al ₂ O ₃ ), for example. An external electrode 106 is provided outside the container 104, and a wiring electrode 108 is led into the container 102 through the wall of the container 104 while being electrically connected thereto. The wiring electrode 108 is bonded to the corresponding electrode on the upper surface of the MEMS device 112 by a wire 110.

  The MEMS device 112 is mounted on the bottom surface of the container 104. As shown in FIG. 3, the MEMS device 112 is mainly composed of, for example, three layers. The silicon substrate that is the second layer 134 is a glass substrate of the first layer 114 and the third layer 156 on the upper and lower surfaces thereof. It is sandwiched and anodically bonded. Since the movable electrode plate 136 serving as a weight is formed on the second layer 134, the movable electrode plate 136 is displaced when the MEMS device 112 is moved up and down by vibration, and the vibration can be measured from the displacement. It is.

  Hereinafter, the configuration of each layer will be described with reference to FIG. It should be noted that the processing and molding of the following components can be easily performed by a semiconductor microfabrication technique (such as a photolithography technique, an etching technique, and a film forming technique).

  The first layer 114 has tapered through holes 124 to 132. 124 is provided to take out the potential of the movable electrode plate 136 of the second layer 134, and 126 to 132 are provided to take out the potential of the electrode extraction islands 144 to 150 provided in the second layer 134. Yes. The surface of the first layer 114 that is in contact with the upper surface of the second layer 134 (the lower surface in the upper diagram of FIG. 4) is electrically connected to the first fixed electrode plate 116 and the first fixed electrode plate 116 for electrode extraction. The detection electrode 118 connected to the island 144, the first braking electrode plate 120, and the braking electrode 122 connected to the electrode extraction island 150 in conduction with the first braking electrode plate 120 are provided. Yes.

  The second layer 134 includes a movable pole plate 136 serving as a weight, an elastic portion 138 having a leaf spring structure that supports the movable plate 136 from the silicon substrate of the second layer 134 and is movable in the vertical direction, and a hole 140 in the electrode extraction island. , 142, electrically isolated islands 144 to 150 for extracting electrodes, a getter hole 152, and a getter 154. The movable electrode plate 136 and the elastic portion 138 are integrally formed on the silicon substrate of the second layer 134 by etching. The side surfaces of the electrode extraction islands 144 to 150 are insulated (for example, formation of a thermal oxide film), and electrical conduction is not achieved even if they are in contact with each other in the holes 140 and 142 of the electrode extraction island. The getter 154 is a gas adsorbent for reducing the influence of gas on the MEMS device 112, for example.

  The third layer 156 is electrically connected to the second fixed electrode plate 158 and the second fixed electrode plate 158 on the surface in contact with the lower surface of the second layer 134 (the upper surface in the lower diagram of FIG. 4). A detection electrode 160 connected to the island 146, a second braking electrode plate 162, and a braking electrode 164 connected to the electrode extraction island 148 in conduction with the second braking electrode plate 162. ing.

  Next, temperature control means provided on the surface of the first layer 114 will be described with reference to FIGS.

  As shown in FIG. 5, the temperature control unit 166 includes a heater 168, a temperature sensor 170, and a processing circuit 172. Then, the processing circuit 172 compares, for example, the AD converter circuit 174 that converts the output signal of the temperature sensor 170 with a digital signal, and the signal output from the AD converter circuit 174 and compares the level with the set temperature. A digital circuit 176 for outputting and a driver circuit 178 for controlling power supply of the heater 168 based on an output signal of the digital circuit 176 can be provided.

  Then, as shown in the top view of the first layer 114 in FIG. 6, a heater 168 is disposed on the surface of the first layer 114 that is directly above the movable electrode plate 136. A temperature sensor 170 is disposed in the vicinity of the heater 168 so that temperature fluctuations can be quickly determined. Further, a processing circuit 172 that processes the driving of the heater 168 and the signal of the temperature sensor 170 and an electrode group 180 for supplying power from the container 104 are provided. The through holes 124 to 132 are provided with electrode patterns 124 a to 132 a made of a metal thin film, and the electrodes 118, 122, 160, and 164 of the second layer 134 are movable through the through holes 124 to 132, respectively. The electrode plate 136 is electrically connected. In addition, since the electrode patterns 124a to 132a have a flat portion on the upper surface of the first layer 114, they can be bonded to the wiring electrode 108 of the container 104 with a wire. Since the first layer 114 is a glass substrate, the temperature sensor 170 and the processing circuit 172 can be formed by a conventional semiconductor manufacturing process by depositing and growing polycrystalline silicon on the surface thereof. In the present embodiment, since the heater 168 is disposed in the vicinity of the processing circuit 172, the semiconductor circuit conditions are adapted and the processing circuit 172 is adapted so that the processing circuit 172 operates stably in the temperature range adjusted by the heater 168. Is preferably formed. As a material of the heater 168, W (tungsten), which is a refractory metal, can be used instead of aluminum wiring as in the processing circuit 172. A specific shape of the heater 168 is shown in FIG. Since the space between the heaters 168a is uniform, heat can be uniformly transmitted to the movable electrode plate 136.

  Next, the operation of this embodiment will be described with reference to FIGS.

  When vibration is applied to the MEMS module 100 from the outside (in the vertical direction in FIG. 2), the movable pole plate 136 supported at the neutral position by the elastic portion 138 is caused by the vibration in the elastic portion 138. Displaces in the thickness direction while being constrained. Thus, the capacitance of the variable capacitor formed by the first fixed plate 116 (FIG. 4) and the movable plate 136, and the second fixed plate 158 (FIG. 4) and the movable plate 136 are formed. The capacitances of the variable capacitance capacitors to be increased and decreased with each other, and the capacitance difference between the two varies. Then, a control unit (not shown) applies a voltage corresponding to the variation of the capacitance difference to the braking electrode plates 120 and 162 (FIG. 4) of the MEMS device 112 via the external electrode 106, thereby The electrostatic force generated in the electrode plates 120 and 162 (FIG. 4) and the inertial force of the movable electrode plate 136 are offset. That is, the vibration can be measured from the magnitude of the voltage applied by the control unit to each braking electrode plate 120, 162 (FIG. 4).

  At this time, if the ambient temperature in which the MEMS module 100 is used fluctuates with an upper limit of 60 ° C., for example, by the temperature control unit 166 described above, a constant temperature between 70 ° C. and 80 ° C. higher than 60 ° C. It is possible to keep the MEMS module 100 at the same time. In this case, since the heater 168 is formed only in the portion directly above the movable electrode plate 136, the temperature in the vicinity of the movable electrode plate 136 of the MEMS module 100 can be kept constant. That is, since the MEMS device 112 operates in a thermally stable state, the gap between the movable electrode plate 136 and the fixed electrode plates 116 and 158 of the MEMS device 112 is kept constant, and the temperature change of the surrounding environment Even if this occurs, the change in characteristics of the MEMS device 112 can be reduced.

  In this embodiment, since the temperature control means 166 is formed in the MEMS device 112, the smallest container 104 for sealing in the atmosphere required by the MEMS device 112 can be selected, so the MEMS module 100 can be reduced in size. Easy to do. Moreover, the power consumption of the heater 168 can be reduced by making the MEMS module 100 small. Furthermore, since the volume is small, the temperature and control of the MEMS device 112 can be easily performed.

  In the present embodiment, the temperature control means 166 is provided on the upper surface of the first layer 114, but the present invention is not limited to this. The temperature control means 166 may be provided on any of the lower surface of the first layer 114, the upper and lower surfaces of the second layer 134, and the upper and lower surfaces of the third layer 156. Alternatively, the function of the temperature control means 166 is divided into each layer. 114, 134, 156 may be arranged. If interference with the wiring pattern of the MEMS device 112 occurs, an insulating film can be formed therebetween to prevent an electrical short circuit. If the heater 168 and the temperature sensor 170 are disposed on the lower surface of the first layer 114, the upper and lower surfaces of the second layer 134, and the upper surface of the third layer 156, the temperature of the movable electrode plate 136 can be controlled closer, The operational stability can be obtained accurately. At that time, since the silicon substrate can be directly heated, the temperature can be controlled with less power consumption.

  Further, the number of heaters 168 and temperature sensors 170 is not limited to one, and a plurality of heaters 168 and temperature sensors 170 may be provided. For example, if the temperature sensors 170 are arranged at a plurality of locations, more accurate temperature measurement is possible, and if the heaters 168 are arranged in a plurality of layers so as to sandwich the movable electrode plate 136, the movable electrode plate 136 can be uniformly and sufficiently heated. Is possible.

  When the temperature adjusting means 166 is formed on the upper surface of the third layer 156, a tapered through hole penetrating the first layer 114 and the second layer 134 is newly provided, so that the upper surface of the third layer 156 can be easily formed. It is possible to establish electrical continuity. Further, when the temperature adjusting means 166 is formed on the lower surface of the third layer 156, if the wiring pattern is formed on the bottom surface of the container 104, wiring can be performed simultaneously with mounting the MEMS device 112.

  In the above-described embodiment, the MEMS device 112 that senses capacitive vibration having the getter 154 has been described, but the present invention is not limited to this. For example, a resistance change type MEMS device may be used. Furthermore, even a MEMS device that responds nonlinearly to temperature can be operated in a stable temperature state, so the present invention is more effective.

  The container 104 is not limited to a ceramic container, and may be sealed with metal sealed containers 102a and 104a as shown in FIG. In the case of the metal sealed containers 102a and 104a, there is an advantage that processing is easy and cracks and chips are hardly generated.

  The material of the heater 168 is not limited to W, but may be Mo (molybdenum), Pt (platinum), or the like. In particular, Pt can be used as a temperature sensor with a high-speed response and high accuracy, and thus has an advantage that the heater 168 and the temperature sensor 170 can be formed at the same time using a photolithography technique. Further, the shape of the heater 168 is not limited to that shown in FIG. 7A, and may be the shape shown in FIG. 7B, for example. Also, instead of generating heat uniformly, the heater wire density is increased at the center to increase the heat value at the center, and conversely, the heater wire density is decreased at the center to reduce the heat value at the center. The heater shape suitable for the configuration of the MEMS device 112 can be obtained.

  Further, the formation of the processing circuit 172 on the glass substrate is not limited to the formation and growth of polycrystalline silicon, and the processing circuit 172 may be formed by growing amorphous silicon. If amorphous silicon is used, the cost can be reduced as compared with polycrystalline silicon. Further, when the processing circuit 172 is formed over the silicon substrate, the electron mobility is higher than that of amorphous silicon or polycrystalline silicon, so that a complicated circuit can be formed with a high processing speed.

  Further, the processing circuit 172 is not limited to the one having the AD conversion circuit 174, the digital circuit 176, and the driver circuit 178. For example, the output value of the temperature sensor 170 may be directly input to the comparator, and the heater 168 may be turned on / off based on the binarized output as a comparison result. Good.

Second Embodiment
A second embodiment according to the present invention will be described with reference to FIG. FIG. 9 is a schematic cross-sectional view of the MEMS module according to this embodiment.

  In the present embodiment, the MEMS device 112b is provided with a temperature sensor 170b and a processing circuit 172b, and the heater 168b is fixed inside the container 104b as a separate member. Other configurations, operations, and the like are the same as those in the first embodiment, and a description thereof will be omitted.

  As shown in FIG. 9A, the heater 168b is mounted between the MEMS device 112b and the bottom surface of the container 104b, and a wire 111b for supplying power to the heater 168b is bonded thereto.

  Also in this embodiment, since the heater 168b is in the vicinity of the MEMS device 112b, the MEMS device 112b operates in a thermally stable state. Therefore, since the gap between the movable electrode plate 136 and the fixed electrode plates 116 and 158 of the MEMS device 112b is kept constant, it is possible to reduce the change in the characteristics of the MEMS device 112b even if the ambient temperature changes. It becomes.

  Further, according to this configuration, the size of the container 104b depends on the area of the heater 168b. However, since the heater 168b is formed as a separate body as the heater, the MEMS module 100b can be easily formed and can be manufactured at low cost. Module 100b can be made. Since the size of the heater 168b is not limited to the size of the MEMS device 112b, the MEMS module 100b can be kept at a high temperature, and the characteristics can be further stabilized.

  FIG. 9B shows a structure of a modification of the present embodiment in which the heater 168c is disposed inside the lid 102c above the MEMS device 112b. In this case, since the heater 168c can be mounted like a lid, the advantage that the positioning of the mounting position of the container 104c and the MEMS device 112b does not have to be strict compared to the case of FIG. Have. In addition, it is possible to save the wire bonding labor by laying an electrode pattern on the inner side surface of the container 104c and directly conducting the electrode pattern when the heater 168c is mounted.

<Third Embodiment>
A third embodiment according to the present invention will be described with reference to FIG. FIG. 10 is a schematic cross-sectional view of the MEMS module according to this embodiment.

  In this embodiment, the MEMS device 112d is provided with a heater 168d, and the temperature sensor / processing circuit 171d is fixed inside the container 104d as a separate member. Other configurations, operations, and the like are the same as those in the first embodiment, and a description thereof will be omitted.

  As shown in FIG. 10A, the temperature sensor / processing circuit 171d is mounted on the upper surface of the MEMS device 112d, and a wire 111d for operating the temperature sensor / processing circuit 171d is bonded thereto.

  Also in this embodiment, since the heater 168d is provided in the MEMS device 112d, the MEMS device 112d operates in a thermally stable state. Therefore, since the gap between the movable electrode plate 136 and the fixed electrode plates 116 and 158 of the MEMS device 112d is kept constant, it is possible to reduce the change in the characteristics of the MEMS device 112d even if the temperature of the surrounding environment changes. It becomes.

  Furthermore, according to this configuration, the size of the container 104d depends on the mounting form of the MEM device 112d and the temperature sensor / processing circuit 171d, but the MEMS device 112d is provided with only a simple heater 168d. The MEMS device 112d can be easily formed as compared with the first and second embodiments. For this reason, the MEMS module 100d can be manufactured at a lower cost. Since the temperature sensor / processing circuit 171d is a separate body, a commercially available temperature sensor / processing circuit 171d can be used. Therefore, even if the manufacturing quantity is not so large, the MEMS module 100d can be manufactured at low cost. It is possible to make

  FIG. 10B shows a structure of a modification of the present embodiment in which the temperature sensor / processing circuit 171e is arranged side by side on the MEMS device 112d. This configuration is suitable when the thickness of the MEMS module 100e is reduced or when priority is given to ensuring the degree of freedom of the wiring pattern on the upper surface of the MEMS device 112d.

<Fourth embodiment>
A fourth embodiment according to the present invention will be described with reference to FIG. FIG. 11 is a schematic cross-sectional view of the MEMS module according to this embodiment.

  In this embodiment, the MEMS device 112f is not provided with the temperature control means 166, and the heater 168f and the temperature sensor / processing circuit 171f are fixed inside the container 104f as separate members. Other configurations, operations, and the like are the same as those in the first embodiment, and a description thereof will be omitted.

  As shown in FIG. 11A, the temperature sensor / processing circuit 171f is mounted side by side with the MEMS device 112f on a heater 168f mounted between the bottom surface of the container 104f and the MEMS device 112f. A wire 111f for operation of the processing circuit 171f is bonded.

  Also in this embodiment, since the heater 168f is in the vicinity of the MEMS device 112f, the MEMS device 112f operates in a thermally stable state. Accordingly, since the gap between the movable electrode plate 136 and the fixed electrode plates 116 and 158 of the MEMS device 112f is kept constant, it is possible to reduce the change in the characteristics of the MEMS device 112f even if the ambient temperature changes. It becomes.

  Furthermore, according to this configuration, the MEMS device 112f is not provided with any temperature control means 166, so that the MEMS device 112f can be easily formed. The size of the container 104f depends on the size of the heater 168f and the mounting form of the MEMS device 112f and the temperature sensor / processing circuit 171f, but the MEMS module 100f can be manufactured at a lower cost. Since the temperature sensor / processing circuit 171f is a separate body, a commercially available temperature sensor / processing circuit 171f can be used. For this reason, even if the manufacturing quantity is not so large, the MEMS module 100f can be manufactured at a low cost. Since the size of the heater 168f is not limited to the size of the MEMS device 112f, it is easy to make the temperature constant at a high temperature.

  FIG. 11B shows a structure of a modification of the present embodiment in which the heater 168g is disposed inside the lid 102g above the MEMS device 112f. In this case, since the heater 168g can be mounted like a lid, there is an advantage that alignment of the mounting positions of the container 104g and the MEMS device 112f does not have to be strict as compared with the case of FIG. Have. In addition, it is possible to save the labor of wire bonding by laying an electrode pattern on the inner side surface of the container 104g and establishing direct conduction with the electrode pattern when the heater 168g is mounted.

<Fifth Embodiment>
A fifth embodiment according to the present invention will be described with reference to FIGS. FIG. 12 is a schematic cross-sectional view of a MEMS module according to the present embodiment, and FIG. 13 is a schematic view of the MEMS module mounted on a printed board.

  In this embodiment, as shown in FIG. 12A, the MEMS device 112h is not provided with the temperature control means 166, and only the separate heater 168h is mounted inside the container 104h. As shown in FIG. 13, the temperature sensor / processing circuit 171h is mounted on the printed circuit board 182 outside the container 104h as a separate member. Other configurations, operations, and the like are the same as those in the first embodiment, and a description thereof will be omitted.

  In this embodiment, the temperature inside the MEMS module 100h is not directly monitored. However, since the temperature sensor / processing circuit 171h is mounted in the vicinity of the MEMS module 100h, the MEMS device 112h is thermally stable. Operate in a state. Therefore, since the gap between the movable electrode plate 136 and the fixed electrode plates 116 and 158 of the MEMS device 112h is kept constant, the change in the characteristics of the MEMS device 112h can be reduced even if the temperature of the surrounding environment changes. It becomes.

  Further, according to this configuration, since the temperature control means 166 is not provided at all in the MEMS device 112h, the formation of the MEMS device 112h is easy. Although the size of the container 104h depends on the size of the heater 168h, the MEMS module 100h can be manufactured at a lower cost than the first to fourth embodiments. Since the temperature sensor / processing circuit 171h is a separate body and mounted outside the container 104h, the limitation of downsizing the temperature sensor 170h and the processing circuit 172h is eased. Commercially available products can be used. Even if the production quantity is not so large, the MEMS module 100h can be manufactured at a low cost. In addition, since the size of the heater 168h is not limited to the size of the MEMS device 112h, it is easy to keep the temperature constant at a high temperature.

  FIG. 12B shows a difference in the arrangement of the heater 168i, which is a structure of a modification of the present embodiment in which the heater 168i is arranged above the MEMS device 112h and inside the lid 102i. In this case, since the heater 168i can be mounted like a lid, the advantage that the positioning of the mounting position of the container 104i and the MEMS device 112h does not have to be strict compared to the case of FIG. Have. In addition, it is possible to save the labor of wire bonding by laying an electrode pattern on the inner side surface of the container 104i and directly conducting the electrode pattern when the heater 168i is mounted.

  In any of the above-described embodiments, the temperature control unit 166 includes the heater 168, the temperature sensor 170, and the processing circuit 172. However, the present invention is not limited to this. The temperature control means 166 is satisfied by having at least the heater 168.

  Further, when the temperature sensor 170 and the processing circuit 172 are separate from the MEMS device 112, the temperature sensor / processing circuit 171d, 171e, 171f, 171g, and 171h are described as being integrated. However, the present invention is not limited to this. It is not something that can be done. When the temperature sensor 170 and the processing circuit 172 are configured on the market, they are often separated into separate packages, and the present invention does not exclude such a case.

  Moreover, in the said embodiment, although the atmosphere of the MEMS module 100 was made into the vacuum, this invention is not limited to this. For example, the present invention is applicable even in an atmosphere in which an inert gas such as Ar (argon) or nitrogen is sealed.

Schematic diagram showing components according to the present invention 1 is a schematic cross-sectional view of a MEMS module according to a first embodiment of the present invention. Similarly, a cross-sectional view of a MEMS device Similarly, an exploded perspective view of the MEMS device Schematic diagram of circuit block for temperature control Similarly, a schematic diagram of an example of circuit arrangement on the upper surface of the MEMS device Similarly, a schematic diagram of the shape of a thin film resistor Similarly, a cross-sectional schematic diagram of a MEMS module according to a modification. Schematic cross-sectional view of a MEMS module according to a second embodiment of the present invention. Schematic cross-sectional view of a MEMS module according to a third embodiment of the present invention. Sectional schematic diagram of the MEMS module according to the fourth embodiment of the present invention. Schematic cross-sectional view of a MEMS module according to a fifth embodiment of the present invention. Schematic diagram of the same MEMS module mounted on a printed circuit board

Explanation of symbols

100, 100a, 100b, 100d, 100f, 100h ... MEMS module 102, 102a-102i ... Lid 104, 104a-104i ... Container 106, 106a ... External electrode 108 ... Wiring electrode 110, 110a-110i, 111a, 111b, 111d- 111h ... wires 112, 112a, 112b, 112d, 112f, 112h ... MEMS device 114 ... first layer 116 ... first fixed electrode plate 118,160 ... detection electrode 120 ... first braking electrode plate 122,164 ... Electrodes for braking 124-132 ... Through holes 124a-132a ... Electrode pattern 134 ... Second layer 136 ... Movable electrode plate 138 ... Elastic portion 140, 142 ... Electrode extraction island holes 144-150 ... Electrode extraction island 152 ... Getter Hole 154 ... Getter 156 ... Third layer 1 58 ... Second fixed electrode plate 162 ... Second brake electrode plate 166 ... Temperature control means 168, 168a, 168b, 168c, 168f, 168g, 168h, 168i ... Heater 170 ... Temperature sensors 171d, 171e, 171f, 171g , 171h ... Temperature sensor / processing circuit 172 ... Processing circuit 174 ... AD converter circuit 176 ... Digital circuit 178 ... Driver circuit 180 ... Electrode group 182 ... Printed circuit board

Claims (4)

In a MEMS module having a MEMS device and a sealed container for sealing and storing the MEMS device in a specific atmosphere,
The MEMS module, wherein at least a part of temperature adjusting means for keeping the MEMS device at a constant temperature higher than the ambient temperature is housed in the sealed container.   The MEMS module according to claim 1, wherein at least a part of the temperature adjusting unit is formed in a MEMS device.   The MEMS module according to claim 1, wherein the temperature adjustment unit includes a heater, a temperature sensor, and a processing circuit that processes a signal of the temperature sensor. Seal the MEMS device in a sealed container that is a specific atmosphere,
A method for stabilizing characteristics of a MEMS module, wherein at least a part of the MEMS device is maintained at a constant temperature higher than an ambient temperature of the sealed container.

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