JP2010197335A - Infrared sensor and method for manufacturing infrared sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for sufficiently ensuring an area for attaching a getter in an inside surface covering a sensor chip. <P>SOLUTION: An infrared sensor 1 includes a semiconductor substrate 3 having a window 2 formed, a lens 5 attached to the semiconductor substrate 3 so as to close the window 2 and transmitting an infrared ray, the sensor chip 7 attached to the semiconductor substrate 3 in an electrically connected state with a detecting surface 12 for detecting the infrared ray directed to the window 2, a cap 8 covering the sensor chip 7 and the getter 10 provided in the inside surface 9 of the cap 8 to adsorb and remove gas which deteriorates a degree of vacuum in a space 14 surrounded by the cap 8, the semiconductor substrate 3 and the lens 5. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an infrared sensor in which a sensor chip capable of detecting infrared is vacuum-sealed and a method for manufacturing the same, and in particular, an inner surface of a cap covering the sensor chip adsorbs and removes a gas that lowers the degree of vacuum. The present invention relates to an infrared sensor provided with a getter and a manufacturing method thereof.

  An infrared sensor that detects infrared rays has an infrared detector composed of an infrared absorption layer and a temperature sensor, absorbs infrared rays by the infrared absorption layer, and measures the temperature change with the temperature sensor to detect infrared rays. Conventional infrared sensors have been used. In recent years, the sensitivity of infrared sensors has been increased for the purpose of downsizing, cost reduction, and arraying. Here, as a means for increasing the sensitivity of a thermal infrared sensor, a method of vacuum-sealing a sensor chip provided with an infrared detector has been proposed. That is, if the heat conduction through the atmosphere is suppressed by vacuum-sealing the sensor chip, the heat dissipation from the infrared detector is reduced, and the temperature change of the infrared absorption layer is increased, thereby improving the sensitivity of the infrared sensor. Can be made.

  Here, FIG. 11 is a schematic longitudinal sectional view showing a configuration of an infrared sensor 70 according to a conventional example. The infrared sensor 70 includes a substrate 71, a sensor chip 72 fixed to the surface of the substrate 71, a cap 73 fixed to the substrate 71 so as to cover the sensor chip 72, and a window portion formed in the cap 73. 74, and a getter 76 provided on the inner surface of the cap 73 (see, for example, Patent Document 1). According to the infrared sensor 70 configured as described above, the infrared light that has entered the cap 73 from the transmission member 75 through the window 74 is detected by the sensor chip 72. The space 77 surrounded by the substrate 71, the cap 73, and the transmission member 75 is evacuated and the sensor chip 72 is vacuum-sealed, so that the sensitivity of the infrared sensor 70 is enhanced. Further, the getter 76 adsorbs and removes the gas that exists inside the space 77 and lowers the degree of vacuum, so that the space 77 is held in a vacuum state.

  On the other hand, FIG.12 and FIG.13 is explanatory drawing for demonstrating the manufacturing method of the infrared sensor 70. FIG. When manufacturing the infrared sensor 70, first, a sensor chip attaching process shown in FIGS. 12A and 12B is performed in the atmosphere. That is, as shown in FIG. 12A, after the sensor chip 72 is fixed to the substrate 71 with the detection surface 78 for detecting infrared rays facing upward, as shown in FIG. 12B, the external leads 79 inserted through the substrate 71 and The sensor chip 72 is electrically connected via the wiring wire 80. Next, a getter activation process (not shown) is performed in the vacuum sealing apparatus. That is, the getter 76 attached to the inner surface of the cap 73 is activated by heating. Next, a cap attaching step shown in FIG. 13A is performed in the vacuum sealing device. That is, the cap 73 to which the getter 76 is attached is fixed to the substrate 71 so as to cover the sensor chip 72. Finally, a transmissive member attaching step shown in FIG. 13B is performed in a vacuum sealing device (not shown). That is, the transmissive member 75 is fixed to the outer surface of the cap 73 so as to close the window portion 74. In summary, after the sensor chip mounting process is performed in the atmosphere, the getter activation process, the cap mounting process, and the transmission member mounting process are performed in the vacuum sealing device.

JP 2006-088088 A

  However, the conventional infrared sensor 70 has a problem that the positioning accuracy of the transmission member 75 with respect to the sensor chip 72 is poor. More specifically, in the infrared sensor 70 shown in FIG. 11, the sensor chip 72 is directly fixed to the substrate 71, while the transmission member 75 is indirectly fixed to the substrate 71 through the cap 73. Accordingly, the positioning accuracy of the transmissive member 75 with respect to the sensor chip 72 has three factors: the positioning accuracy of the transmissive member 75 with respect to the cap 73, the positioning accuracy of the cap 73 with respect to the substrate 71, and the positioning accuracy of the sensor chip 72 with respect to the substrate 71. Determined by. Thus, it is difficult to accurately position the transmissive member 75 with respect to the sensor chip 72 due to the large number of affected factors. Thus, when the positioning accuracy of the transmission member 75 with respect to the sensor chip 72 is poor, it is necessary to secure a margin of sufficient width for joining the cap 73 to the edge of the transmission member 75 so as not to cause a sealing defect. Therefore, the transmissive member 75 is enlarged, leading to an increase in size and cost of the entire device. In particular, when a lens that collects infrared rays is used as the transmissive member 75, an error is likely to occur in focusing and optical axis alignment.

  Further, the conventional infrared sensor 70 has a problem in that it cannot store a sufficient amount of getter 76 that can keep the inside of the space 77 shown in FIG. 11 in a high vacuum state for a long period of time. More specifically, as described above, the getter 76 is attached to the inner surface of the cap 73. However, in recent years, the size of the cap 73 is being reduced in size as the infrared sensor 70 is being reduced in size. Furthermore, since the window 73 is formed in the cap 73, the area allocated to the getter 76 is reduced by the amount of the window 74. Accordingly, a sufficient amount of getter 76 corresponding to the size of the space 77 cannot be accommodated, or the amount of adsorbed gas approaches the total gas amount that is the performance limit, and the performance of the getter 76 deteriorates. The degree of vacuum of 77 may decrease.

  In addition, in the conventional method for manufacturing the infrared sensor 70, it is necessary to perform three assembly processes, ie, a getter activation process, a cap mounting process, and a transmission member mounting process, in the vacuum sealing apparatus. However, the complexity of the infrared sensor 70 is poor.

  The present invention has been made in view of such a problem, and provides means for positioning a transmission member with high accuracy with respect to a sensor chip. Further, a means for sufficiently securing a region for attaching the getter to the inner side surface of the cap covering the sensor chip is provided. Furthermore, a means for improving the productivity of the infrared sensor is provided by simplifying the work in the vacuum sealing apparatus.

  In order to achieve the above object, an infrared sensor according to the present invention includes a substrate on which a window portion for introducing infrared rays is formed, and a transmission member that is attached to the substrate so as to close the window portion and transmits infrared rays. And a sensor chip attached to the substrate in an electrically connected state with a detection surface capable of detecting infrared rays directed toward the window, and attached to the substrate so as to cover the sensor chip And a cap.

  The infrared sensor according to the present invention includes a substrate on which a window portion for introducing infrared rays is formed, a transmission member that is attached to the substrate so as to close the window portion and transmits infrared rays, and detects infrared rays. A sensor chip attached to the substrate in an electrically connected state with a possible detection surface facing the window portion, and a cap attached to the substrate so as to cover the sensor chip; A getter that is provided on an inner surface of the cap and that adsorbs and removes a gas that lowers the degree of vacuum in a space surrounded by the cap, the substrate, and the transmission member.

  Moreover, the infrared sensor which concerns on this invention is provided with the said getter so that electricity supply is possible.

  In the infrared sensor according to the present invention, the transmission member is attached to the substrate via an intermediate plate having a thermal expansion coefficient larger than that of the transmission member and smaller than that of the substrate.

  In the infrared sensor according to the present invention, the sensor chip is attached to the substrate in an electrically connected state by soldering a solder bump provided on the detection surface to the substrate. It is.

  In the infrared sensor according to the present invention, the sensor chip is fixed to a wiring board on which a predetermined wiring is formed and a solder bump protrudes, and the wiring board and the sensor chip are connected via a wiring wire. The sensor chip is attached to the substrate in an electrically connected state by soldering solder bumps of the wiring board to the substrate.

  In the infrared sensor according to the present invention, the sensor chip is fixed to the substrate, and the substrate and the sensor chip are electrically connected via a wiring wire, whereby the sensor chip is electrically connected. It is attached to the substrate in a state of being connected to the substrate.

  Moreover, the infrared sensor which concerns on this invention has an unevenness | corrugation formed in the inner surface of the said cap.

  In the infrared sensor according to the present invention, the getter is further provided on a surface opposite to the detection surface of the sensor chip.

  In addition, the method for manufacturing an infrared sensor according to the present invention is such that, in the atmosphere, a transparent member that transmits infrared light is blocked with respect to a substrate formed with a window portion through which infrared light is introduced. A transmissive member mounting step for mounting the sensor chip, a sensor chip mounting step for mounting the sensor chip with the detection surface capable of detecting infrared rays directed toward the window in the atmosphere, and the inside of the vacuum sealing device And a cap attaching step of attaching a cap to the substrate so as to cover the sensor chip.

  In addition, the method for manufacturing an infrared sensor according to the present invention reduces the degree of vacuum of a space provided on the inner surface of the cap and surrounded by the substrate, the cap, and the transmission member in the vacuum sealing device. It further includes a getter activation step of heating and activating the getter that adsorbs and removes the gas.

  In the infrared sensor according to the present invention, the sensor chip is directly fixed to the substrate, and the transmission member is also directly fixed to the substrate. As a result, the positioning accuracy of the transmissive member with respect to the sensor chip is determined when the positioning of the transmissive member and the sensor chip is indirectly performed via the substrate. It is determined by two factors, positioning accuracy. Further, the positioning accuracy of the transmissive member with respect to the sensor chip is determined by one factor of the positioning accuracy of the transmissive member with respect to the sensor chip when the transmissive member and the sensor chip are directly positioned. Therefore, like the conventional infrared sensor, the transmission member is indirectly fixed to the substrate through the cap, and the positioning accuracy of the transmission member with respect to the sensor chip is the positioning accuracy of the transmission member with respect to the cap, and the positioning of the cap with respect to the substrate. Compared with the case where the accuracy and the accuracy of positioning of the sensor chip on the substrate are determined, the transmission member can be accurately positioned with respect to the sensor chip as the number of affected factors decreases. . If the positioning accuracy of the transmission member is improved in this way, the margin width provided for joining the cap to the edge of the transmission member can be minimized. Cost can be reduced. In addition, when a lens is used as the transmissive member, there is an advantage that an error hardly occurs in the focusing and optical axis alignment of the lens.

  In the infrared sensor according to the present invention, a window for introducing infrared rays is formed on the substrate. Therefore, compared with the conventional infrared sensor in which the window portion is formed on the cap, a wider area for mounting the getter can be secured on the inner side surface of the cap. As a result, the amount of getter attachment increases, so that the interior of the space surrounded by the cap, the substrate, and the transmission member can be more reliably maintained in a high vacuum state over a long period of time.

  In the infrared sensor according to the present invention, the gas adsorption capacity can be maximized by energizing and heating the getter.

  In addition, in the infrared sensor according to the present invention, the thermal expansion coefficient of the transmission member and the substrate can be reduced even when the transmission member is attached to the substrate via the intermediate plate, even when the infrared sensor is subjected to high temperature conditions in the manufacturing process of the infrared sensor. Due to the difference, it is difficult for a defect to occur at a location where the transmission member is fixed to the substrate.

  Moreover, in the infrared sensor according to the present invention, the sensor chip can be attached to the substrate in an electrically connected state by an easy operation only by soldering.

  In the infrared sensor according to the present invention, even a sensor chip without a solder bump can be attached to a substrate in an electrically connected state via a wiring board.

  In the infrared sensor according to the present invention, even a sensor chip without a solder bump can be attached to a substrate in an electrically connected state. Furthermore, since no other member is interposed between the sensor chip and the substrate, the number of parts does not increase.

  Further, in the infrared sensor according to the present invention, since the surface area of the inner side surface of the cap is increased by forming the irregularities, a wider area for mounting the getter can be secured. As a result, as the amount of getters attached increases, the interior of the space can be more reliably maintained in a high vacuum state over a long period of time.

  In addition, in the infrared sensor according to the present invention, since the getter is provided on the surface opposite to the detection surface of the sensor chip, the amount of getter attachment increases, so that the interior of the space can be more reliably and over a long period of time. And maintain a high vacuum.

  Moreover, in the manufacturing method of the infrared sensor which concerns on this invention, a transmissive member attachment process is performed in air | atmosphere, and only a cap attachment process is performed within a vacuum sealing device. Therefore, compared with the conventional case where the cap mounting process and the transmissive member mounting process are performed in the vacuum sealing device, the work in the vacuum sealing device that requires complicated work is simplified, and the productivity of the infrared sensor is reduced. Can be improved.

  In the infrared sensor manufacturing method according to the present invention, the transmissive member is attached to the substrate instead of the cap. Therefore, when the getter attached to the inner surface of the cap is activated, the transmissive member itself or the reflection coated on the surface thereof is applied. A member having low heat resistance such as a prevention coating material is not exposed to a high temperature.

1 is a schematic longitudinal sectional view showing an infrared sensor according to a first embodiment of the present invention. It is explanatory drawing for demonstrating the manufacturing method of an infrared sensor, Comprising: The figure which showed the process in air | atmosphere. It is explanatory drawing for demonstrating the manufacturing method of an infrared sensor, Comprising: The figure which showed the process in a vacuum sealing apparatus. The schematic longitudinal cross-sectional view which shows the infrared sensor which concerns on 2nd Example of this invention. The schematic longitudinal cross-sectional view which shows the infrared sensor which concerns on 3rd Example of this invention. The schematic longitudinal cross-sectional view which shows the infrared sensor which concerns on 4th Example of this invention. The schematic longitudinal cross-sectional view which shows the infrared sensor which concerns on 5th Example of this invention. The schematic longitudinal cross-sectional view which shows the infrared sensor which concerns on 6th Example of this invention. The schematic longitudinal cross-sectional view which shows the infrared sensor which concerns on 7th Example of this invention. The schematic longitudinal cross-sectional view which shows the infrared sensor which concerns on 8th Example of this invention. The schematic longitudinal cross-sectional view which shows the structure of the infrared sensor 70 concerning a prior art example. Explanatory drawing for demonstrating the manufacturing method of the infrared sensor 70. FIG. Explanatory drawing for demonstrating the manufacturing method of the infrared sensor 70. FIG.

  First, the configuration of the infrared sensor according to the first embodiment of the present invention will be described. FIG. 1 is a schematic longitudinal sectional view showing an infrared sensor 1 according to the first embodiment. The infrared sensor 1 is fixed to the substrate 3 on which the window portion 2 is formed, the lens (transmission member) 5 fixed to the front side surface 4 of the substrate 3 so as to close the window portion 2, and the back side surface 6 of the substrate 3. A sensor chip 7, a cap 8 fixed to the back side surface 6 of the substrate 3 so as to cover the sensor chip 7, and a getter 10 attached to the inner side surface 9 of the cap 8. .

  The substrate 3 is a flat plate member made of alumina or the like, which is a material widely used for LSI packages. As shown in FIG. 1, the substrate 3 is formed with a window portion 2 for penetrating the central portion thereof for introducing infrared rays. A plurality of external leads 11 are appropriately connected to the substrate 3. In addition, the shape of the board | substrate 3 and the window part 2 is not limited to a present Example, A design change is possible suitably. Moreover, the material which comprises the board | substrate 3 is not limited to an alumina, For example, you may comprise the board | substrate 3 by forming an insulating film on silicon | silicone and carrying out metal wiring on it.

  The lens 5 is for condensing infrared rays and is made of chalcogenide glass capable of transmitting infrared rays. As shown in FIG. 1, the edge portion of the lens 5 is fixed to the front side surface 4 of the substrate 3 by soldering or the like, thereby closing the opening of the window portion 2. Here, although not shown in detail in FIG. 1, the lens 5 has its optical axis, that is, a line passing through the center passing through the center of the sensor chip 7, and its focal length is equal to the distance to the sensor chip 7. Are arranged as follows. In this embodiment, the lens 5 is used as the transmitting member according to the present invention. However, instead of this, a flat plate member made of chalcogenide glass may be used. Furthermore, germanium, silicon, zinc sulfide, or the like may be employed as the member that can transmit infrared rays, in addition to chalcogenide glass. In the present embodiment, the window portion 2 is closed by fixing the lens 5 to the front side surface 4 of the substrate 3, but the window portion 2 may be closed by fitting the lens 5 to the window portion 2. Alternatively, the lens portion 5 may be fixed to the back side surface 6 of the substrate 3 to close the window portion 2, and the sensor chip 7 may be disposed on the opposite side of the window portion 2 with the lens 5 interposed therebetween via a predetermined gap. .

  The sensor chip 7 detects infrared rays by converting light energy into heat energy. As shown in FIG. 1, the sensor chip 7 has one surface configured as a detection surface 12 capable of detecting infrared rays. Although not shown in detail in FIG. 1, an infrared absorption layer that absorbs infrared rays and an infrared absorption layer. And a temperature sensor for measuring the temperature change. A plurality of solder bumps 13, which are spherical electrodes made of a solder material, are provided protruding from the outer edge portion of the detection surface 12 of the sensor chip 7. As shown in FIG. 1, the sensor chip 7 configured in this manner is provided with the solder bumps 13 on the back side surface 6 of the substrate 3 with the detection surface 12 facing the window portion 2. Each is soldered to an electrode terminal (not shown). Thus, the sensor chip 7 is attached to the substrate 3 in an electrically connected state.

  The cap 8 is for vacuum-sealing the sensor chip 7. As shown in FIG. 1, the cap 8 is disposed so as to cover the sensor chip 7, and an opening edge portion thereof is fixed to an outer edge portion of the back side surface 6 of the substrate 3 by soldering or the like. Then, as will be described later, a cap attaching step for attaching the cap 8 to the substrate 3 is performed in a vacuum sealing device (not shown). As a result, the space 14 surrounded by the cap 8, the substrate 3, and the lens 5 is in a high vacuum state with a degree of vacuum of about 1 Pa, and the sensitivity of the sensor chip 7 is enhanced.

  The getter 10 is for holding the inside of the space 14 in a vacuum state. More specifically, inside the space 14 is a gas that remains during the operation in the vacuum sealing device or a gas that is generated thereafter, and the presence of these gases reduces the degree of vacuum in the space 14. The getter 10 has a characteristic of adsorbing a gas in an activated state, and plays a role of adsorbing and removing the gas existing inside the space 14. The getter 10 is a thin film getter that can be formed by vapor deposition, and is vapor deposited over the entire side surface 15 and bottom surface 16 constituting the inner side surface 9 of the cap 8 as shown in FIG.

  Next, functions and effects of the infrared sensor 1 according to the first embodiment will be described. In the infrared sensor 1 configured as described above, the infrared light incident on the lens 5 passes through the lens 5, passes through the window portion 2 of the substrate 3, and is collected around the detection surface 12 of the sensor chip 7. As a result, the light is absorbed by the infrared absorption layer provided on the detection surface 12. And when the temperature of the infrared absorption layer rises by absorbing infrared rays, infrared rays are detected by changing the output of the temperature sensor.

  Here, in the infrared sensor 1, the sensor chip 7 is directly fixed to the substrate 3, and the lens 5 is also directly fixed to the substrate 3. Thereby, the positioning accuracy of the lens 5 with respect to the sensor chip 7 is determined when the positioning of the lens 5 and the sensor chip 7 is indirectly performed through the substrate 3, and the positioning accuracy of the lens 5 with respect to the substrate 3 and the sensor chip. 7 is determined by two factors of positioning accuracy to the substrate 3. Further, the positioning accuracy of the lens 5 with respect to the sensor chip 7 is determined by one factor, that is, the positioning accuracy of the lens 5 with respect to the sensor chip 7 when the lens 5 and the sensor chip 7 are directly positioned. . More specifically, for example, the lens 5 and the sensor chip 7 can be obtained by superimposing the jig holding the lens 5 and the jig holding the sensor chip 7 on the jig holding the substrate 3 immovably. Is attached to the substrate 3, the positioning accuracy of the lens 5 with respect to the sensor chip 7 is determined by two factors: the positioning accuracy of the lens 5 with respect to the substrate 3 and the positioning accuracy of the sensor chip 7 with respect to the substrate 3. On the other hand, when the substrate 3 and the sensor chip 7 are attached to the lens 5 by superimposing the jig holding the substrate 3 and the jig holding the sensor chip 7 on the jig holding the lens 5 immovably. The positioning accuracy of the lens 5 with respect to the sensor chip 7 is determined by one factor, that is, the positioning accuracy of the sensor chip 7 with respect to the lens 5. Therefore, like the conventional infrared sensor 70 shown in FIG. 11, the transmissive member 75 is indirectly fixed to the substrate 71 via the cap 73, and the positioning accuracy of the transmissive member 75 with respect to the sensor chip 72 is high. Compared with the case where the positioning accuracy to 73, the positioning accuracy of the cap 73 to the substrate 71, and the positioning accuracy of the sensor chip 72 to the substrate 71 are determined, the number of affected factors is reduced. The lens 5 can be accurately positioned with respect to the sensor chip 7, and there is an advantage that an error is unlikely to occur in focusing and optical axis alignment of the lens 5.

  Further, in the present infrared sensor 1, since the lens 5 is fixed to the substrate 3, the sensor from the lens 5 is compared with the case where the transmission member 75 is fixed to the cap 73 as in the conventional infrared sensor 70 shown in FIG. The distance to the chip 7 can be shortened. Thereby, there is an advantage that the lens 5 can be made small, leading to cost reduction and downsizing of the entire device.

  In the infrared sensor 1, a window portion 2 for introducing infrared rays is formed on the substrate 3. Therefore, as compared with the case where the window 74 is formed in the cap 73 as in the conventional infrared sensor 70 shown in FIG. 11, a wider area for mounting the getter 10 can be secured on the inner surface 9 of the cap 8. . As a result, as the amount of getter 10 attached increases, the interior of the space 14 can be more reliably maintained in a high vacuum state for a long period of time.

  Next, a method for manufacturing the infrared sensor 1 according to the first embodiment will be described. 2 and 3 are explanatory views for explaining a method of manufacturing the infrared sensor 1, wherein FIG. 2 shows a process in the atmosphere, and FIG. 3 shows a process in the vacuum sealing device. . When the infrared sensor 1 is manufactured, first, the transmitting member attaching step shown in FIG. 2A is performed in the atmosphere. That is, the lens 5 is arranged on the front side surface 4 of the substrate 3 so as to close the window portion 2, and the edge portion of the lens 5 is fixed to the substrate 3 by soldering or the like. Next, the sensor chip attachment process shown in FIG. 2B is performed in the atmosphere. That is, the sensor chip 7 is disposed on the back side surface 6 of the substrate 3 with the detection surface 12 facing the window portion 2 side. The plurality of solder bumps 13 provided so as to protrude from the detection surface 12 are soldered to electrode terminals (not shown) provided on the back side surface 6 of the substrate 3, whereby the sensor chip 7 is mounted on the substrate. Fix to 3. The transmitting member attaching step and the sensor chip attaching step are not limited to the present embodiment, and can be performed in an arbitrary order.

  Next, a getter activation process (not shown) is performed in the vacuum sealing apparatus. That is, the getter 10 provided on the inner surface 9 of the cap 8 is activated by heating to 300 ° C. or higher. Next, a cap attaching step shown in FIG. 3 is performed in the vacuum sealing device. That is, the cap 8 to which the getter 10 is attached is disposed on the back side surface 6 of the substrate 3 so as to cover the sensor chip 7, and the opening edge thereof is fixed to the substrate 3 by soldering or the like. Thereby, the infrared sensor 1 is completed.

  Next, the effect of the manufacturing method of the infrared sensor 1 according to the first embodiment will be described. As described above, in the manufacturing method of the infrared sensor 1, after performing the transmitting member attaching process and the sensor chip attaching process in the atmosphere, the getter activation process and the cap attaching process are performed in the vacuum sealing device. Therefore, the transmission member is compared with the manufacturing method of the conventional infrared sensor 70 in which the getter activation process, the cap installation process, and the transmission member installation process are performed in the vacuum sealing apparatus after the sensor chip installation process in the atmosphere. Since the attachment process is performed in the atmosphere, the assembly process in the vacuum sealing apparatus is reduced from three processes to two processes. In this manner, the productivity of the infrared sensor 1 can be improved by simplifying the work in the vacuum sealing apparatus that requires complicated work. Further, since the lens 5 is attached to the substrate 3 instead of the cap 8, when the getter 10 attached to the inner surface 9 of the cap 8 is activated, the heat resistance such as the antireflection coating material coated on the lens 5 itself or the surface thereof is activated. Are not exposed to a high temperature of 300 ° C. or higher.

  Next, the configuration of the infrared sensor 20 according to the second embodiment of the present invention will be described. FIG. 4 is a schematic longitudinal sectional view showing the infrared sensor 20 according to the second embodiment. The infrared sensor 20 is different from the infrared sensor 1 according to the first embodiment in the configuration of the getter 21. Since the other configuration is the same as that of the first embodiment, the same reference numerals as those in FIG. The getter 21 according to the present embodiment is a thick film getter formed on a metal plate, and is attached to the bottom surface 16 constituting the inner surface 9 of the cap 8. The attachment position of the getter 21 may be the side surface 15 constituting the inner side surface 9 of the cap 8 or the back side surface 6 of the substrate 3. If a thick film getter is employed as the getter 21 in this way, there is an advantage that the getter 21 can be easily fixed to the cap 8 or the substrate 3 by conventionally known YAG welding or spot welding.

  Next, the configuration of the infrared sensor 30 according to the third embodiment of the present invention will be described. FIG. 5 is a schematic longitudinal sectional view showing the infrared sensor 30 according to the third embodiment. Compared with the infrared sensor 1 according to the first embodiment, the infrared sensor 30 also has a different getter 31 configuration. Since the other configuration is the same as that of the first embodiment, the same reference numerals as those in FIG. The getter 31 according to the present embodiment is a thick film getter as in the second embodiment, and a pair of left and right through electrodes 32 penetrating the cap 8 are connected to both ends in the longitudinal direction. According to such a configuration of the getter 31, if a voltage is applied between the through electrodes 32 and the getter 31 is energized, the getter 31 is heated and the gas adsorbing ability is maximized. is there.

  Next, the configuration of the infrared sensor 40 according to the fourth embodiment of the present invention will be described. FIG. 6 is a schematic longitudinal sectional view showing the infrared sensor 40 according to the fourth embodiment. Compared with the infrared sensor 1 according to the first embodiment, the infrared sensor 40 is different in the attachment structure of the lens 5 to the substrate 3. Since the other configuration is the same as that of the first embodiment, the same reference numerals as those in FIG. 1 are given in FIG. 6 and the description thereof is omitted. The lens 5 according to the present embodiment is fixed to the intermediate plate 41 by soldering or the like, and the intermediate plate 41 is fixed to the front side surface 4 of the substrate 3 by soldering or the like. Here, the intermediate plate 41 has a coefficient of thermal expansion larger than that of the lens 5 and smaller than that of the substrate 3. Thus, by attaching the lens 5 to the substrate 3 through the intermediate plate 41, even when the infrared sensor 40 is subjected to high temperature conditions in the manufacturing process, the difference in thermal expansion coefficient between the lens 5 and the substrate 3 is caused. In addition, it is difficult for defects to occur at the locations where the lens 5 is fixed to the substrate 3.

  Next, the configuration of the infrared sensor 50 according to the fifth embodiment of the present invention will be described. FIG. 7 is a schematic longitudinal sectional view showing the infrared sensor 50 according to the fifth embodiment. The infrared sensor 50 is different from the infrared sensor 1 according to the first embodiment in the mounting structure of the sensor chip 7 on the substrate 3. Since the other configuration is the same as that of the first embodiment, the same reference numerals as those in FIG. 1 are given in FIG. 7, and the description thereof is omitted. The sensor chip 7 according to the present embodiment is the same as the first embodiment in that one surface is configured as a detection surface 12 capable of detecting infrared rays, but the detection surface 12 is similar to the first embodiment. Solder bumps 13 are not provided. The sensor chip 7 has a surface 51 opposite to the detection surface 12 fixed to the wiring board 52 by soldering or adhesive. The wiring board 52 is formed with predetermined wiring (not shown), and a plurality of solder bumps 53, which are spherical electrodes made of a solder material, protrude from the edge of the wiring board 52. The wiring board 52 configured as described above is such that each solder bump 53 is provided with an electrode terminal (not fixed) on the back side surface 6 of the substrate 3 with the detection surface 12 of the sensor chip 7 facing the window portion 2 side. Are soldered to each other. Furthermore, the electrode terminal 54 provided on the detection surface 12 of the sensor chip 7 and the electrode terminal 55 provided on the wiring board 52 are electrically connected by a wiring wire 56. According to such a mounting structure of the sensor chip 7 to the substrate 3, even when the sensor chip 7 is not provided with the solder bump 13 as in the first embodiment, the sensor chip 7 is electrically connected. It can be attached to the substrate 3.

  Next, the configuration of the infrared sensor 60 according to the sixth embodiment of the present invention will be described. FIG. 8 is a schematic longitudinal sectional view showing an infrared sensor 60 according to the sixth embodiment. The infrared sensor 60 is different from the infrared sensor 1 according to the first embodiment in the mounting structure of the sensor chip 7 on the substrate 3. Since the other configuration is the same as that of the first embodiment, the same reference numerals as those in FIG. 1 are given in FIG. 8, and the description thereof is omitted. The sensor chip 7 according to the present embodiment is the same as the first embodiment in that one surface thereof is configured as a detection surface 12 capable of detecting infrared rays, but the detection surface 12 is similar to the first embodiment. Solder bumps 13 are not provided. In the sensor chip 7, the edge of the detection surface 12 is fixed to the back side surface 6 of the substrate 3 by soldering or adhesive. The electrode terminal 61 provided on the detection surface 12 of the sensor chip 7 and the electrode terminal 62 provided on the substrate 3 are electrically connected by a wiring wire 63. According to such a mounting structure of the sensor chip 7 to the substrate 3, even if the solder bump 13 is not provided as in the sensor chip 7 of the first embodiment, the sensor chip 7 is electrically connected. It can be attached to the substrate 3. Further, since the sensor chip 7 is directly fixed to the substrate 3 without using the wiring board 52 as in the fifth embodiment, the number of parts does not increase.

  Next, the configuration of the infrared sensor 70 according to the seventh embodiment of the present invention will be described. FIG. 9 is a schematic longitudinal sectional view showing an infrared sensor 70 according to the seventh embodiment. The infrared sensor 70 differs from the infrared sensor 1 according to the first embodiment in the configuration of a cap 71 and a getter 72. Since other configurations are the same as those in the first embodiment, the same reference numerals as those in FIG. 1 are given in FIG. 9 and the description thereof is omitted. The cap 71 according to the present embodiment has a plurality of irregularities 75 formed on the bottom surface 74 constituting the inner surface 73 thereof, and a getter 72 is deposited so as to cover the entire surface of each irregularity 75. According to such a configuration, since the surface area of the inner side surface 73 of the cap 71 is increased, a wider area for mounting the getter 72 can be secured. As a result, the amount of getter 72 attached increases, so that the interior of the space 14 can be more reliably maintained in a high vacuum state over a long period of time. Although not shown in detail in the drawing, the unevenness 75 can be formed also on the side surface 76 constituting the inner side surface 73 of the cap 71.

  Next, the configuration of the infrared sensor 80 according to the eighth embodiment of the present invention will be described. FIG. 10 is a schematic longitudinal sectional view showing an infrared sensor 80 according to the eighth embodiment. The infrared sensor 80 is different in the configuration of the getter 81 from the infrared sensor 1 according to the first embodiment. Since the other configuration is the same as that of the first embodiment, the same reference numerals as those in FIG. 1 are given in FIG. 10 and the description thereof is omitted. The getter 81 according to the present embodiment is deposited not only on the inner surface 9 of the cap 8 but also on the back surface 82 of the sensor chip 7, that is, the surface opposite to the detection surface 12. According to such a configuration, the amount of getter 81 attached is increased by the amount deposited on the back side surface 82 of the sensor chip 7, so that the interior of the space 14 is more reliably maintained in a high vacuum state for a long period of time. be able to.

  Next, functions and effects of the infrared sensors 20 to 80 according to the second to eighth embodiments will be described. According to the infrared sensors 20 to 80 according to the second to eighth embodiments configured as described above, the same operational effects as those of the infrared sensor 1 according to the first embodiment can be obtained. However, the infrared sensor 40 according to the fourth embodiment shown in FIG. 6 is different from the first embodiment in that the lens 5 is not directly fixed to the substrate 3, and the infrared sensor 50 according to the fifth embodiment shown in FIG. Unlike the first embodiment, since the sensor chip 7 is not directly fixed to the substrate 3, there is no effect that the lens 5 can be accurately positioned with respect to the sensor chip 7.

  Next, a method for manufacturing the infrared sensors 20 to 80 according to the second to eighth embodiments and the function and effect thereof will be described. Compared with the manufacturing method of the infrared sensor 1 according to the first embodiment, the manufacturing method of the infrared sensors 20 to 80 according to the second to eighth embodiments has a difference in work of each process according to the difference in configuration. However, a getter for activating the getter 10 in the vacuum sealing device is performed by performing a transmissive member attaching process for attaching the lens 5 to the substrate 3 in the atmosphere and performing a sensor chip attaching process for attaching the sensor chip 7 to the substrate 3 in the atmosphere. A common point is that an activation process is performed and a cap mounting process for mounting the cap 8 to the substrate 3 in the vacuum sealing apparatus is performed. Therefore, according to the manufacturing method of the infrared sensors 20 to 80 according to the second to eighth embodiments, in the vacuum sealing apparatus that requires complicated work, similar to the manufacturing method of the infrared sensor 1 according to the first embodiment. The productivity of the infrared sensors 20 to 80 can be improved by simplifying the operation. Moreover, since the lens 5 is attached to the board | substrate 3, when activating the getter 10, the lens 5 itself and the antireflection coating material coat | covered on the surface are not exposed to high temperature.

  The infrared sensor and the manufacturing method thereof according to the present invention are applicable to an infrared sensor in which a sensor chip capable of detecting infrared rays is vacuum-sealed and a getter is provided on an inner surface of a cap that covers the sensor chip.

DESCRIPTION OF SYMBOLS 1 Infrared sensor 2 Window part 3 Board | substrate 5 Lens (transmission member)
7 Sensor chip 8 Cap 9 Inner side surface 10 Getter 12 Detection surface 13, 53 Solder bump 14 Space 41 Intermediate plate 52 Wiring board 56, 63 Wiring wire 75 Unevenness

Claims (11)

A substrate on which windows for introducing infrared rays are formed;
A transparent member that is attached to the substrate so as to close the window and transmits infrared rays;
A sensor chip attached to the substrate in an electrically connected state so that a detection surface capable of detecting infrared rays faces the window portion side,
A cap attached to the substrate so as to cover the sensor chip;
An infrared sensor comprising: A substrate on which windows for introducing infrared rays are formed;
A transparent member that is attached to the substrate so as to close the window and transmits infrared rays;
A sensor chip attached to the substrate in an electrically connected state so that a detection surface capable of detecting infrared rays faces the window portion side,
A cap attached to the substrate so as to cover the sensor chip;
A getter that is provided on an inner surface of the cap and that adsorbs and removes a gas that lowers the degree of vacuum in a space surrounded by the cap, the substrate, and the transmission member;
An infrared sensor comprising:   The infrared sensor according to claim 1, wherein the getter is provided to be energized.   The infrared sensor according to claim 2, wherein the transmissive member is attached to the substrate via an intermediate plate having a thermal expansion coefficient larger than that of the transmissive member and smaller than that of the substrate.   5. The sensor chip according to claim 1, wherein the sensor chip is attached to the substrate in an electrically connected state by soldering a solder bump provided on the detection surface to the substrate. The infrared sensor in any one.   The sensor chip is fixed to a wiring board on which a predetermined wiring is formed and a solder bump protrudes, and the wiring board and the sensor chip are electrically connected via a wiring wire. The infrared sensor according to claim 1, wherein the sensor chip is attached to the substrate in an electrically connected state by soldering the solder bumps to the substrate.   The sensor chip is fixed to the substrate, and the substrate and the sensor chip are electrically connected via wiring wires, so that the sensor chip is attached to the substrate in an electrically connected state. The infrared sensor according to claim 1, wherein the infrared sensor is provided.   The infrared sensor according to claim 2, wherein unevenness is formed on an inner surface of the cap.   The infrared sensor according to claim 2, wherein the getter is further provided on a surface opposite to the detection surface of the sensor chip. In the atmosphere, a transparent member attaching step for attaching a transparent member that transmits infrared rays so as to close the window portion, with respect to a substrate formed by penetrating a window portion for introducing infrared rays;
In the atmosphere, a sensor chip mounting step for mounting a sensor chip so that a detection surface capable of detecting infrared rays is directed toward the window portion with respect to the substrate;
In a vacuum sealing device, a cap attaching step of attaching a cap to the substrate so as to cover the sensor chip;
The manufacturing method of the infrared sensor characterized by including.   In a vacuum sealing apparatus, a getter that is provided on the inner surface of the cap and that adsorbs and removes a gas that lowers the degree of vacuum in the space surrounded by the substrate, the cap, and the transmitting member is heated and activated. The method for manufacturing an infrared sensor according to claim 10, further comprising a getter activating step.

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