JP5982973B2 - Vacuum package, method for manufacturing vacuum package, and sensor - Google Patents

Description

  The present invention relates to a package in which functional elements are vacuum-sealed and a manufacturing method thereof.

  In order to improve the performance of functional devices such as an infrared sensor, a pressure sensor, and an acceleration sensor, it is desirable that they are housed in a vacuum sealed container to function.

  As a method of sealing a vacuum package such as an infrared sensor, for example, in Patent Document 1, a through hole for exhaust is provided in an infrared transmission window, a sealing material is placed in an opening of the through hole, and the inside of the package is vacuumed. There is a method of sealing the through hole by heating and melting the sealing material.

  Japanese Patent Laid-Open No. 11-326037

  In the sealing method described in Patent Document 1, a pad for a sealing material that is a metal coating is formed around the opening of the through hole, and a sealing material such as a solder ball is disposed in the through hole to perform pressure reduction and heating. Therefore, there is a problem that the sealing material moves and is removed from the opening of the through hole when the internal gas is exhausted, and the sealing material is not held on the through hole. In addition, when the sealing material is heated and melted, there is a problem that the sealing material flows so as to avoid the opening, or falls through the through hole, so that the through hole cannot be completely sealed. Prone to occur.

  An object of the present invention is to provide a vacuum package structure that solves the above problems and does not cause a sealing failure, and a method for manufacturing the same.

  In order to solve the above-described problems, a vacuum package according to the present invention is a vacuum package having a vacuum-sealed cavity, a main substrate, and a sealing cover having a cavity on the main substrate and covering the main substrate. The sealing cover has a through-hole for exhausting the cavity and a plug for sealing the through-hole, and the plug is made of a material having a lower coefficient of thermal expansion than the sealing cover. To do.

  In order to solve the above problems, a sensor of the present invention is a sensor having a vacuum-sealed cavity, an element for detecting an electromagnetic wave, a main board on which the element is mounted, an electromagnetic wave facing the main board and emitting an electromagnetic wave. A transmissive window that is transmissive, a sealing cover that faces the main substrate and fixes the periphery of the transmissive window, and is provided at an edge of the main substrate and the sealing cover, and faces the main substrate and the transmissive substrate through a space. A spacer installed in the sealing cover, a through hole for exhausting a cavity surrounded by the main substrate, the transmission window, the sealing cover and the spacer, and a plug for sealing the through hole, The stopper is made of a material having a lower coefficient of thermal expansion than the sealing cover.

  In order to solve the above-described problem, a vacuum package manufacturing method includes a method of vacuum-sealing a cavity surrounded by a main substrate and a sealing cover that covers the main substrate. A step of inserting a plug into the through hole for exhausting air, a step of setting a package in which the plug is installed in the through hole in the vacuum chamber, and heating the vacuum package to determine the thermal expansion coefficient of the plug and the sealing cover. Because of the difference, a step of creating a gap between the stopper and the sealing cover, a step of reducing the pressure inside the vacuum chamber, exhausting the cavity through the gap, and cooling the vacuum package, the through hole is sealed with the stopper. And a process.

  The present invention realizes a vacuum package structure and a manufacturing method thereof that do not cause a sealing failure.

1 is a schematic cross-sectional view of a vacuum package according to a first embodiment of the present invention. It is the perspective view and sectional view of a stopper concerning a 1st embodiment of the present invention. _{(Mn 0.96 Fe 0.04) 3 (} Zn 0.5 Ge 0.5) is a diagram showing characteristics of expansion and contraction due to temperature of the material of N. It is a conceptual diagram which shows the relationship between the vacuum package temperature in the sealing process of the vacuum package of 1st Embodiment of this invention, the diameter of the through-hole of a sealing cover, the diameter of the protrusion part of a stopper, and the vacuum degree of a chamber. It is a schematic explanatory drawing about shrinkage | contraction of the stopper at the time of a heating, and expansion of a through-hole. It is a schematic explanatory drawing about the primary vacuum sealing by expansion | swelling of the stopper at the time of cooling, and shrinkage | contraction of a through-hole. It is a schematic sectional drawing on the heating and pressure reduction conditions of the vacuum package which concerns on the 2nd Embodiment of this invention. It is a schematic sectional drawing of the through-hole periphery in each sealing process of the vacuum package which concerns on 3rd Embodiment of this invention. It is a schematic sectional drawing of the infrared sensor which concerns on the 4th Embodiment of this invention. It is a schematic sectional drawing of the infrared sensor which concerns on the 5th Embodiment of this invention.

  Hereinafter, the vacuum package according to the first embodiment of the present invention will be described. FIG. 1 is a schematic cross-sectional view of a vacuum package according to a first embodiment of the present invention.

  The vacuum package includes a substrate 1 serving as a bottom surface and a sealing cover 2 that covers the substrate 1 in a state where a cavity is secured above the substrate 1. The substrate 1 and the sealing cover 2 are joined. The sealing cover 2 is made of a material having a positive coefficient of thermal expansion. The sealing cover 2 includes a through hole 3 that serves as an outlet for exhaust when evacuating. The through hole 3 is a circular hole that penetrates the sealing cover 2. The through hole 3 is formed in the sealing cover 2 using a drill, a sand blaster, ultrasonic machining, wire electric discharge machining, anisotropic etching, isotropic etching, dry etching, or the like.

  In the vacuum package, the substrate 1 and the sealing cover 2 are installed in a vacuum chamber, the gas inside the sealing cover 2 is exhausted from the through hole 3, and then the through hole 3 is sealed to seal the inside of the sealing cover 2. The cavity is evacuated.

  The through-hole 3 is sealed by closing the opening of the through-hole 3 with a plug 4 and covering the gap between the vacuum package and the plug 4 and the plug 4 itself with a sealing material A5.

  FIG. 2 shows a perspective view and a sectional view of the stopper 4. The plug 4 is a stepped integrated structure composed of a head portion 4 a that covers the upper surface of the through hole 3 of the sealing cover 2 and a protruding portion 4 b that closes the inner diameter of the through hole 3. The plug 4 uses a material having a thermal expansion coefficient smaller than that of the sealing cover 2. For example, a material having a negative coefficient of thermal expansion is used.

  Both the head 4a and the protrusion 4b are cylindrical, and the protrusion 4b is connected to the center of the circle of the head 4a in the direction perpendicular to the head 4a. The diameter of the head portion 4 a is larger than the diameter of the through hole 3, and the diameter of the protrusion 4 b is almost the same as the diameter of the through hole 3. Further, the surface of the head portion 4a on the side of the sealing cover 2 has a groove 4c that becomes a gap through which air is released when vacuuming. The groove 4c communicates from the outer edge of the head portion to the outer edge of the protruding portion 4b. A plurality of grooves may be provided instead of only one, and grooves may be provided on the sealing cover side.

  Note that the shape of the bottom surface of the through-hole 3 and the protrusion 4b is not limited to a circle, as long as the protrusion 4b can be inserted into the opening of the through-hole 3 and can be tightly sealed. Is optimal. The head portion 4a of the stopper is for preventing a drop when a gap with the hole is generated, and it is sufficient that there is a portion larger than the diameter of the protruding portion 4b, and it is not always necessary to have a cylindrical shape.

  Hereinafter, specific material names will be given and described in more detail.

As a material having a negative coefficient of thermal expansion, a mixture of Mn ₃ GeN and Mn ₃ XN is known. Manganese nitride Mn ₃ XN having a structure called “reverse perovskite” whose main raw material is manganese, zinc, copper or the like is obtained by replacing 20 to 70% of zinc or gallium with germanium (Ge) at 100 ° C. The volume decreases continuously over a certain temperature range. A negative expansion material can be obtained by mixing Mn ₃ GeN and Mn ₃ XN at an appropriate ratio and firing. The negative expansion material has a property that the volume shrinks when the temperature is raised and the volume expands when the temperature is lowered. Typically, zirconium tungstate (ZrW ₂ O ₈ ), silicon oxide (Li ₂ O—Al ₂ O ₃ —nSiO ₂ ), iron oxide (SrCu ₃ Fe ₄ O ₁₂ ), manganese compound (Mn ₃ Cu _{1 -X} Ge _X N), etc. In addition, there are Invar alloys (36% nickel, 64% iron).

  The coefficient of thermal expansion is one of the indices indicating the degree of thermal expansion, and represents how much the volume changes with respect to the reference temperature.

FIG. 3 is a diagram showing the characteristics of expansion and contraction due to the temperature of the material of (Mn _0.96 Fe _0.04 ) ₃ (Zn _0.5 Ge _0.5 ) N.
This material hardly expands and contracts from 25 ° C. to 60 ° C. at normal temperature, but greatly contracts when it exceeds 60 ° C. Since this material can be handled as a material having a negative coefficient of thermal expansion in the range of 25 ° C. to 110 ° C. at room temperature, the case where this material is used for the plug 4 will be described below.
The amount of shrinkage when heated from 25 ° C. to 110 ° C. at normal temperature can be regarded as equivalent to that when heated from 60 ° C. to 110 ° C. Assuming that the diameter at normal temperature is D, the expansion / contraction amount is δD, and the thermal expansion coefficient of the above material is α = −25 μ / ° C., from δD = D · α · (T2−T1)
δD = 10 × (−0.025) × 0.001 × (110-60) = − 0.0125 mm
It becomes.
On the other hand, stainless steel is used as the material for the vacuum package.
SUS304 18μm × 10 ^-6 / ℃
Therefore, the case where SUS304 is used for the sealing cover 2 will be described below.
The amount of expansion and contraction δD when SUS304 is heated from room temperature 25 ° C to 110 ° C is:
δD = 10 × 0.018 × 0.001 × (110−25) = 0.0153 mm
It becomes.

  The through hole 3 of the sealing cover 2 (SUS304) is formed to φ10H5 (diameter 10 mm, tolerance 0 to 6 μm), and the projection 4 b of the plug 4 is φ10p5 (JIS standard diameter 10 mm, tolerance 12 to 17 μm). The gap between the protrusions 4b at normal temperature is −6 to −17 μm, and the through hole 3 and the stopper 4 are firmly fitted at normal temperature.

Here, when the package is heated from room temperature 25 ° C. to 110 ° C., the through hole 3 becomes 15.3 μm larger, and the protrusion 4b of the plug 4 becomes 12.5 μm smaller. Expands to .8μm.
When the gap is 10.8μm, the area of the gap is approximate.
10 × π × 0.0108 ≒ 0.0291mm ²
It becomes.

This value is sufficiently larger than the minimum size of the through hole 3φ 0.1 mm (0.000078 mm ² ) when vacuum-sealing a vacuum package (14 mm × 14 mm × 1.4 mm). The gap between the parts 4b is secured so that it can be evacuated without any problem.

  Below, the sealing method of the said vacuum package is demonstrated.

  FIG. 4 is a conceptual diagram showing the relationship between the vacuum package temperature, the diameter of the through hole of the sealing cover, the diameter of the plug protrusion, and the degree of vacuum of the chamber in the vacuum package sealing process.

First, the protrusion 4 b of the plug 4 is inserted into the through hole 3 of the sealing cover 2. At normal temperature, the diameter of the circle on the bottom surface of the protrusion 4b of the plug 4 is slightly larger than the diameter of the circular hole of the through hole 3, so that the plug 4 can be press fitted. Alternatively, the plug 4 is inserted into the through-hole 3 in a state in which the plug 4 is heated and contracted in advance using the negative coefficient of thermal expansion. The plug 4 inserted into the through hole 3 is firmly fitted into the through hole 3 at room temperature. (S1 temporary sealing process)
Next, a vacuum package in which the through hole 3 is temporarily sealed with a stopper is placed on a stage in the vacuum chamber, and the vacuum chamber is evacuated.

When a predetermined degree of vacuum is reached, heating of the vacuum package is started.
The diameter of the through hole 3 of the sealing cover increases as the temperature increases. On the other hand, the diameter of the protrusion 4b of the plug hardly changes up to 60 ° C, but contracts when it exceeds 60 ° C.
When the temperature rises and the diameter of the through-hole 3 increases and the diameter of the plug projection 4b shrinks, a gap is generated in the fitted portion. When the temperature reaches about 110 ° C., the gap becomes large enough for exhaust. The gap and the groove provided in the head portion 4a of the plug serve as a vent for exhausting, and the air in the vacuum package can be exhausted (S2 vent forming process). In FIG. 5, the schematic about the shrinkage | contraction of the stopper 4 at the time of a heating and expansion of the through-hole 3 is shown. The heat treatment may be performed on the entire vacuum package or only on the local area near the through hole 3 and the stopper 4.

Then, the temperature is maintained at about 110 ° C. for a while, and the gas in the vacuum package is discharged until the vacuum is reached. (S3 exhaust process)
When the vacuum package becomes vacuum, the temperature of the vacuum package is lowered to close the gap. As the temperature decreases, the diameter of the through hole 3 of the sealing cover 2 decreases and the diameter of the protrusion of the plug expands, so that the gap between the through hole 3 and the protrusion 4b becomes smaller. When the room temperature is reached, the diameter of the through-hole 3 and the diameter of the protrusion 4b return to the original size, and the original fitting state is achieved, so that the vacuum sealing of the vacuum package is completed (S4 primary vacuum sealing step). FIG. 6 is a schematic view showing a state in which the primary vacuum sealing is performed by returning to normal temperature and expanding the stopper 4 and contracting the through hole 3.

After that, the vacuum in the vacuum chamber is released, and the vacuum package sealed with the primary vacuum is taken out of the vacuum chamber, and the gap between the sealing cover 2 and the stopper 4 and the stopper 4 itself are sealed with adhesive or solder in the atmosphere. Seal with material A5. (S5 secondary vacuum sealing process)
Needless to say, the secondary vacuum sealing can be omitted when sufficient airtight reliability is obtained by the primary vacuum sealing.

  As described above, in the first embodiment of the present invention, the plug 4 made of a material having a negative coefficient of thermal expansion is contracted by heating, and the through hole 3 of the sealing cover 2 made of a material having a positive thermal expansion is expanded. A vacuum package is vacuum-sealed by creating a gap for exhausting the gas in the interior and returning the plug 4 and the through hole 3 to their original sizes by cooling after exhausting.

  Next, a vacuum package according to a second embodiment of the present invention will be described. FIG. 7 is a schematic cross-sectional view of the vacuum package according to the second embodiment under heating and decompression conditions. In the second embodiment, the vacuum package has a protrusion 17 around the through hole 13 on the top surface of the sealing cover 12.

  The protrusion 17 around the through-hole 13 has a C-shape with a notch in part. The notch is used as a vent for evacuation. When the protrusion 14 b of the plug 14 is inserted into the through hole 13, the protrusion 17 of the sealing cover 12 contacts the lower surface of the head portion 14 a of the plug 14.

  The vacuum package is evacuated through the gap between the protrusion 14b and the sealing cover 12 under the heating / depressurization condition and the gap that is the notch of the protrusion 17 around the through hole 13.

  Note that the number of notches, the shape and size of the protrusions are such that a gap that can be evacuated is secured, and the head portion 14a of the stopper and the sealing cover 12 face each other substantially in parallel. If it is, various shapes are employable. In the case where the sealing cover 12 is manufactured by press molding, such projections can be easily formed at the same time as the molding of the sealing cover 12. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  Next, a vacuum package according to a third embodiment of the present invention will be described. FIG. 8 is a schematic cross-sectional view around the through hole in each sealing step of the vacuum package according to the third embodiment of the present invention. In the third embodiment, the shape of the plug 24 for sealing the through hole 23 is different.

  In the third embodiment, the plug has a truncated cone shape in which the protruding portion 24b is tapered. The circle on the upper surface of the protrusion 24 b is larger than the through hole 23, and the circle on the lower surface of the protrusion 24 b is smaller than the through hole 23. For this reason, the plug 24 does not fall out of the through hole 23. The head portion of the plug 24 has a cylindrical shape with the same radius as the circle on the upper bottom of the truncated cone of the protrusion 24b. In the third embodiment, the head portion above the plug 24 may not be provided.

Below, the sealing method of the vacuum package which concerns on 3rd Embodiment is demonstrated. FIG. 8 shows a state of insertion of the vacuum package in each of the operation steps (S1) to (S5) of the vacuum package sealing method according to the third embodiment.
The plug 24 is inserted into the through-hole 23 with the pointed end thereof being vertically downward. The through hole 23 is formed by making a circular hole in the sealing cover 22 with a drill or the like.

  The plug 24 is inserted into the through hole 23 of the sealing cover 22 at room temperature. Since the plug 24 has a taper on the protrusion 24b, it is not necessary to control the diameter of the through hole 23 and the diameter of the protrusion 24b with high accuracy. There is no need to insert or insert it in a heated and contracted state, which is advantageous.

Next, the vacuum package temporarily sealed with the plug 24 is inserted into the vacuum chamber. When heated, the volume of the plug 24 shrinks and the through hole 23 expands, so that a gap is formed between the plug 24 and the sealing cover 22, and the plug 24 falls downward due to its own weight.
The plug 24 is hooked when the gap between the projection 24b and the through hole 23 disappears. In the third embodiment, evacuation is performed in this state. Vacuuming is performed where there is no gap, but since the protrusion 24b is only lightly hooked at the corner of the through hole 23 of the sealing cover 22, vacuuming is sufficiently performed from a minute gap such as the surface roughness of the corner. Is called.

  When the temperature is returned to room temperature after completion of evacuation, the plug 24 expands at the position where it is hooked and the through hole 23 contracts, so that the plug 24 bites into the corner of the through hole 23 and is vacuum-sealed. .

  In the third embodiment, since the protruding portion 24b is tapered, the bonding area between the protruding portion 24b and the through-hole 23 is smaller than that of the cylindrical shape. However, if the periphery of the protrusion 24b and the plug 24 itself are sealed with a sealing material A25 such as an adhesive or solder after being taken out from the vacuum chamber, confidentiality can be improved.

  Further, by providing a taper on the through hole 23 side and making the angle of the taper of the protrusion 24b substantially the same, the fitting area of the through hole 23 and the protrusion 24b at the time of sealing is increased, and the confidentiality is further increased. Can be increased.

  Next, a fourth embodiment of the present invention will be described. In the fourth embodiment, an example in which the vacuum package according to the first embodiment is applied to an infrared sensor in which an infrared light receiving element is vacuum-sealed as a functional element will be described. FIG. 9 is a schematic sectional view of a vacuum package according to the fourth embodiment of the present invention.

  The vacuum package includes an infrared light receiving element 100 that detects infrared light, a light receiving element substrate 101 on which the infrared light receiving element 100 is mounted, an infrared transmission window 106 that transmits infrared light so that the infrared light reception element 100 can receive light, and an infrared transmission window 106. And a sealing cover 102 that fixes the periphery of the substrate through a sealing material B108 such as solder or adhesive. The sealing cover 102 is attached to the light receiving element substrate 101 via a spacer 107. Further, when the sealing cover 102 is made of a material having a thermal expansion coefficient smaller than that of the stopper and transmitting infrared rays, the infrared transmitting window 106 can be omitted.

  The sealing cover 102 has at least one through hole 103 used for exhausting the inside of the vacuum package. The through hole 103 is a circular hole that penetrates the sealing cover 102. The plug 104 has a stepped shape. The through-hole 103 is temporarily sealed with the protruding portion of the plug 104 inserted into the through-hole 103, and is further evacuated while being heated, and then cooled, thereby cooling the through-hole. The opening 103 is first vacuum sealed with a plug 104. Further, a secondary vacuum sealing is performed in which the gap between the stopper 104 and the sealing cover 102 and the stopper 104 itself are covered with a sealing material A105 such as an adhesive or solder. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  Next, a fifth embodiment of the present invention will be described. The fifth embodiment is different from the example applied to the infrared sensor according to the fourth embodiment in that the infrared transmitting window is joined to the central portion of the stopper. FIG. 10 is a schematic cross-sectional view of an infrared sensor according to the fifth embodiment of the present invention.

The vacuum package includes an infrared light receiving element 200 for detecting infrared light, a light receiving element substrate 201 on which the infrared light receiving element 200 is mounted, a sealing cover 202 having a through hole 203 that covers the light receiving element substrate 201 and serves as an exhaust outlet, and a through hole. The hole 203 is closed, and an infrared transmission window 206 that transmits infrared rays is provided at the center so that the infrared light receiving element 200 can receive light. The sealing cover 202 is attached to the light receiving element substrate 201 through the spacer 207. Regarding the infrared transmission window 206, when the sealing cover 202 is made of a material having a thermal expansion coefficient smaller than that of the sealing cover 202 and transmitting infrared rays, the infrared transmission window 206 can be omitted.
Since other configurations are the same as those in the first embodiment, description thereof is omitted.

  As in the first embodiment, a plug 204 having an infrared transmission window 206 is inserted into the through hole 203 of the sealing cover 202 at room temperature and temporarily sealed. Note that an infrared transmitting window 206 is joined to the stopper 204 in advance by a sealing material B208 such as solder or adhesive.

  Next, the temporarily sealed vacuum package is placed in a vacuum chamber, and vacuuming is started simultaneously with heating the vacuum package. With heating, a gap is formed between the stopper 204 and the sealing cover 202 due to a difference in thermal expansion coefficient between the stopper 204 and the sealing cover 202. The air in the vacuum package is exhausted outside through this gap.

  The vacuum package is discharged until the inside of the vacuum package is evacuated with a gap between the stopper 204 and the sealing cover 202. In the fifth embodiment, since the diameters of the plug 204 and the through hole 203 are larger than those in the fourth embodiment, it is possible to perform evacuation better because the gap area formed when heated is larger.

When the vacuum package becomes vacuum, the vacuum package is cooled and primary vacuum sealing is performed.
It is taken out of the vacuum chamber, and the secondary vacuum sealing is performed in the atmosphere with a sealing material A205 such as an adhesive or solder around the gap between the sealing cover 202 and the stopper 204 and the periphery of the stopper 204. Since other configurations are the same as those of the fourth embodiment, description thereof is omitted.

  In addition, although this invention was demonstrated based on the said embodiment, it cannot be overemphasized that various changes, a deformation | transformation, improvement, etc. are included in the scope of the present invention, without being limited to the said embodiment. Further, various combinations, substitutions or selections of the disclosed elements are possible within the scope of the present invention.

In the above embodiment, the vacuum package related to the infrared sensor using the infrared light receiving element as the functional element has been described. However, the functional element of the present invention is not limited to the infrared light receiving element, and a vacuum such as a piezoelectric element or a vibration element is used. Various functional elements that require sealing can be applied to the present invention. That is, it goes without saying that the vacuum package of the present invention can be applied to a pressure sensor and an acceleration sensor in addition to the infrared sensor.
(Supplementary Note 1) In a vacuum package having a vacuum sealed cavity, the vacuum package includes a main substrate, a sealing cover having a cavity on the main substrate and covering the main substrate, and the sealing The cover has a through-hole for exhausting the cavity and a plug for sealing the through-hole, and the plug is made of a material having a lower coefficient of thermal expansion than the sealing cover. To vacuum package.
(Supplementary note 2) The vacuum package according to supplementary note 1, wherein the sealing cover is made of a material having a positive coefficient of thermal expansion, and the plug is made of a material having a negative coefficient of thermal expansion.
(Additional remark 3) The said stopper is a stepped shape which consists of a base material part which covers the said through-hole upper surface, and a projection part of the substantially same magnitude | size as the said through-hole provided in the said base material part, The said projection part is The vacuum package according to appendix 1 or 2, wherein the through hole is sealed in a state of being inserted into the through hole.
(Additional remark 4) The said base material part has a groove | channel communicated from the outer edge of the said base material part to the outer edge of the said protrusion part in at least one part of the surface in which the said protrusion part was provided. plug.
(Additional remark 5) The said sealing cover has a convex part in the periphery of the said through-hole, The vacuum package in any one of Additional remarks 1-3 characterized by the above-mentioned.
(Supplementary note 6) The vacuum package according to Supplementary note 1 or 2, wherein the plug has a larger upper surface than the through hole, and has a taper with a tip that becomes thinner in the insertion direction of the through hole.
(Supplementary note 7) The vacuum package according to any one of Supplementary notes 1 to 6, wherein the vacuum package further covers the plug sealing the through hole with a sealing material.
(Appendix 8) A sensor having a vacuum-sealed cavity, an element that detects electromagnetic waves, a main board on which the elements are mounted, a transmission window that faces the main board and transmits the electromagnetic waves, A sealing cover that faces the main substrate and fixes the periphery of the transmission window, and is provided at an edge of the main substrate and the sealing cover so that the main substrate and the transmission substrate are opposed to each other with a space. An installed spacer, a through hole provided in the sealing cover, for exhausting the hollow portion surrounded by the main substrate, the transmission window, the sealing cover, and the spacer; and the through hole A sensor for sealing, wherein the stopper is made of a material having a lower coefficient of thermal expansion than the sealing cover.
(Additional remark 9) In the manufacturing method of the vacuum package which vacuum-seals the cavity part enclosed by the main board | substrate and the sealing cover which covers the said main board | substrate, in order to exhaust the said cavity part provided in the said sealing cover Inserting the plug into the through-hole, setting the package having the plug installed in the through-hole in the vacuum chamber, heating the vacuum package, and thermal expansion of the plug and the sealing cover Due to the difference in rate, a step of creating a gap between the stopper and the sealing cover, a step of reducing the pressure in the vacuum chamber and exhausting the cavity through the gap, and cooling the vacuum package And a step of sealing the through-hole with the stopper.
(Supplementary note 10) The vacuum package according to supplementary note 9, further comprising a step of covering the stopper sealing the through hole with a sealing material after sealing the through hole with the stopper. Production method.
(Appendix 11) The sealing cover is made of a material having a positive coefficient of thermal expansion, the plug is made of a material having a negative coefficient of thermal expansion, and when the vacuum package is heated, the plug is contracted to enlarge the through hole. The manufacturing method of the vacuum package of Additional remark 9 or 10 characterized by producing a clearance gap between the said sealing material and the said sealing cover.
(Additional remark 12) It is a sensor which has the cavity part vacuum-sealed, Comprising: The element which detects electromagnetic waves, The main board | substrate which mounts the said element, It has a cavity part on the said main board | substrate, and covers the said main board | substrate A sealing cover, a spacer provided at an edge of the main substrate and the sealing cover, the main substrate and the sealing cover being disposed so as to face each other with a space; and the sealing cover A through hole for evacuating the cavity surrounded by the main substrate, the transmission substrate, the sealing cover, and the spacer; and a transmission substrate that seals the through hole and transmits the electromagnetic wave. A plug disposed in a central portion, wherein the plug is made of a material having a lower coefficient of thermal expansion than the sealing cover.

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Sealing cover 3 Through-hole 4 Plug 4a Head part 4b Protrusion part 4c Groove 5 Sealing material A
DESCRIPTION OF SYMBOLS 11 Board | substrate 12 Sealing cover 13 Through-hole 14 Plug 14a Head part 14b Projection part 17 Protrusion part 22 Sealing cover 23 Through-hole 24 Plug 24b Projection part 25 Sealing material A
DESCRIPTION OF SYMBOLS 100 Infrared light receiving element 101 Light receiving element board | substrate 102 Sealing cover 103 Through-hole 104 Plug 105 Sealing material A
106 Infrared transmitting window 107 Spacer 108 Sealing material B
200 Infrared light receiving element 201 Light receiving element substrate 202 Sealing cover 203 Through hole 204 Plug 205 Sealing material A
206 Infrared transmitting window 207 Spacer 208 Sealing material B

Claims (5)

In a vacuum package having a vacuum sealed cavity,
The vacuum package is
A main board;
And a sealing cover which covers the main substrate having the hollow portion to the main substrate,
A through hole provided in the sealing cover for exhausting the cavity;
Wherein said plug has a, a plug for sealing the through hole Ri thermal expansion coefficient lower material der than the sealing cover,
The stopper has a stepped shape including a base part that covers the top surface of the through hole and a protrusion having a size substantially the same as the through hole provided in the base part, and the protrusion is used as the through hole. The through hole is sealed in the inserted state,
The vacuum package according to claim 1 , wherein the base material part has a groove that communicates from an outer edge of the base material part to an outer edge of the protrusion part on at least a part of the surface on which the protrusion part is provided . The vacuum package according to claim 1, wherein the sealing cover is made of a material having a positive coefficient of thermal expansion, and the plug is made of a material having a negative coefficient of thermal expansion. The vacuum package according to claim 1 or 2 , wherein the vacuum package further covers the plug sealing the through hole with a sealing material. In a vacuum package manufacturing method for vacuum-sealing a hollow portion surrounded by a main substrate and a sealing cover covering the main substrate,
A step of inserting a plug into a through hole provided in the sealing cover for exhausting the cavity,
Setting a package in which the plug is installed in the through hole in a vacuum chamber;
Heating the vacuum package, and creating a gap between the plug and the sealing cover from the difference in thermal expansion coefficient between the plug and the sealing cover;
Reducing the pressure in the vacuum chamber and exhausting the cavity through the gap;
Cooling the vacuum package, and sealing the through-hole with the stopper. 5. The method of manufacturing a vacuum package according to claim 4 , further comprising the step of covering the plug sealing the through hole with a sealing material after sealing the through hole with the plug.

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