JP2015088660A - Package and electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a package etc. which is excellent in sealing reliability of an electronic component.SOLUTION: A package 1 includes: an insulation substrate 6 having a recessed part 4; a mounting part 3 which is provided on a bottom surface of the recessed part 4, the mounting part 3 on which an electronic component 11 is mounted; a heater 5a which is provided on the bottom surface or an inner wall of the recessed part 4; a temperature measuring metal layer 5b which is provided on the bottom surface or the inner wall of the recessed part 4 separated from the heater 5a; a heater terminal 8a which is provided on an outer surface of the insulation substrate 6 and connected with the heater 5a; and a temperature measuring terminal 8b which is provided on the outer surface of the insulation substrate 6 and connected with the temperature measuring metal layer 5b.

Description

  The present invention relates to a package and an electronic device having a recess and a vacuum sensor formed in the recess.

  2. Description of the Related Art Conventionally, electronic component storage packages (hereinafter simply referred to as “packages”) for storing electronic components such as infrared sensors, semiconductor elements, and crystal resonators are known (see, for example, Patent Document 1). An electronic device is configured by attaching an electronic component to the mounting portion of such a package and joining a lid for hermetically sealing the mounted electronic component to the upper surface of the package via a sealing material. Is done. In addition, the space (accommodation space) in which the electronic components are accommodated is evacuated by, for example, a vacuum pump. Such an electronic device is used as a component of an information processing device such as a detection device, a mobile phone, or a personal computer.

JP 2007-95956 A

  By the way, in order to improve the characteristics and reliability of the electronic component mounted on the mounting portion, the housing space is preferably in a vacuum state as much as possible. However, after the electronic component is hermetically sealed and the accommodation space is in a vacuum state, the degree of vacuum of the accommodation space may gradually decrease due to gas generated from the electronic component, the insulating base, the connection member, and the like. . When the degree of vacuum in the housing space is reduced, the characteristics and reliability of the electronic component mounted on the mounting portion are decreased. For example, when the electronic component is an infrared sensor, if the degree of vacuum in the housing space is reduced, heat is easily transmitted from the outside, so that the detection sensitivity is reduced. In addition, for example, when the electronic component is a crystal resonator, the oscillation characteristics are degraded when the degree of vacuum in the housing space is decreased. That is, when the degree of vacuum is lowered, the vibration of the infrared sensor and the crystal resonator is hindered, so that the characteristics and reliability are lowered. Therefore, it is necessary to detect whether the accommodation space is in a vacuum state.

  A package according to one aspect of the present invention includes an insulating base having a recess, a mounting portion provided on a bottom surface of the recess, on which an electronic component is mounted, a heater provided on a bottom surface or an inner wall of the recess, A temperature measuring metal layer provided on a bottom surface or an inner wall of the recess apart from the heater, a heater terminal provided on the outer surface of the insulating base, connected to the heater, and an outer surface of the insulating base And a temperature measuring terminal connected to the temperature measuring metal layer.

  An electronic device according to another aspect of the present invention includes the package configured as described above, the electronic component mounted on the mounting portion, and a lid that seals the recess.

  A package according to one aspect of the present invention includes an insulating base having a recess, a mounting portion provided on the bottom surface of the recess, on which an electronic component is mounted, a heater provided on the bottom surface or the inner wall of the recess, and the heater. The temperature measuring metal layer provided on the bottom or inner wall of the recess, the heater terminal provided on the outer surface of the insulating base, connected to the heater, and the temperature measuring metal provided on the outer surface of the insulating base Since the temperature measuring terminal connected to the layer is provided, it is possible to detect whether the housing space is in a vacuum state after sealing the recess.

  Since the electronic device according to another aspect of the present invention has the package having the above-described configuration, an electronic device with improved characteristics and reliability of the electronic component can be provided.

(A) is a top view except the cover in the electronic device of embodiment of this invention, (b) is sectional drawing in the AA of the electronic device shown to (a). (A) is a top view except the cover in the other example of the electronic device of embodiment of this invention, (b) is sectional drawing in the AA of the electronic device shown to (a).

  A package according to an embodiment of the present invention will be described with reference to the accompanying drawings. The distinction between the upper and lower sides in the following description is for convenience, and does not limit the upper and lower sides when a package or the like is actually used.

  The electronic device has a package 1, an electronic component 11, and a lid 2.

  The package 1 has an insulating base 6, a mounting portion 3, a heater 5a and a temperature measuring metal layer 5b that constitute a vacuum sensor 5, a heater terminal 8a, and a temperature measuring terminal 8b.

  Examples of the electronic component 11 include an infrared sensor, a semiconductor element, and a crystal resonator. The electronic component 2 is not limited to this, and may be, for example, a semiconductor laser diode, a photodiode, or the like.

  The insulating base 6 has a recess 4, and a mounting portion 3 on which an electronic component 11 is mounted is provided on the bottom surface of the recess 4.

  The insulating base 6 is formed of a ceramic sintered body such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, or a glass ceramic sintered body. The insulating base 6 may be formed by laminating a plurality of insulating layers made of such a ceramic sintered body.

  If the insulating base 6 is formed by laminating a plurality of insulating layers made of an aluminum oxide sintered body, for example, it can be manufactured by the following method. First, an appropriate organic binder and solvent are added to and mixed with raw material powders such as aluminum oxide, silicon oxide, magnesium oxide and calcium oxide to form a slurry, which is then formed into a sheet by a doctor blade method or a calender roll method. Thus, a ceramic green sheet is obtained, a suitable punching process is performed on the ceramic green sheet, and a plurality of the ceramic green sheets are laminated as necessary, and fired at a high temperature (about 1600 ° C.).

The insulating base 6 has a vacuum sensor 5 formed in the recess 4. The vacuum sensor 5 includes a heater 5a and a temperature measuring metal layer 5b, and is provided on the bottom surface or the inner wall of the recess 4 so as to be separated from each other.
Further, on the outer surface of the insulating base 6, a heater terminal 8a for electrically connecting the heater 5a to the power source and a temperature measuring metal for electrically connecting the temperature measuring metal layer 5b to the temperature measuring device are provided. Terminal 8b is provided.

  The vacuum sensor 5 does not directly measure the degree of vacuum in the recess 4, and the pressure of the gas in the recess 4, that is, the degree of vacuum, is calculated by the following two methods. By combining these two methods, a wide range of pressures can be detected.

In the first method, the heater 5a generates heat, and the temperature in the recess 4 is measured by a temperature measuring device through the temperature measuring metal layer 5b. Since the measured temperature is obtained by the amount of heat obtained by subtracting the amount of heat taken by the gas molecules in the recess 4 from the amount of heat generated by the heater 5a, the amount of heat absorbed by the gas molecules is estimated. The pressure of the gas in the recess 4 is calculated from the amount of heat absorbed by the gas, and the degree of vacuum is obtained. In this method, a pressure of 1 × 10 ⁻¹ to 10 ³ Pa can be detected. The degree of vacuum can be automatically obtained by connecting a processing device for calculating the degree of vacuum from the measured temperature.

In the second method, a device for measuring a voltage and a current applied to cause the heater 5a to generate heat is connected to the heater terminal 8a, and a change in voltage is measured while keeping the current constant. When the voltage rises with the current kept constant, the energy applied to the heater has increased due to heat loss due to the gas in the recess 4, and the amount of heat absorbed by the gas is estimated from this increased energy. And the pressure of the gas in the recessed part 4 is computed from this calorie | heat amount similarly to the said method, and a vacuum degree is obtained. In this method, a pressure of 1 × 10 ⁻³ to 10 ⁻¹ Pa can be detected. The degree of vacuum can be automatically obtained by connecting a processing device for calculating the degree of vacuum from the measured current and voltage.

  Since the package 1 is configured as described above, the vacuum state of the space in the recess 4 after the recess 4 is sealed with the lid 2 can be detected.

  The heater 5a and the temperature measuring metal layer 5b constituting the vacuum sensor 5 are preferably provided at positions where the heater 3a and the temperature measuring metal layer 5b do not sandwich the mounting portion 3 in plan view. With this configuration, only the gas in the recess 4 exists between the heater 5a and the temperature measuring metal layer 5b, and the heat from 5a is applied to the temperature measuring metal layer 5b via the electronic component 11. Since it is not transmitted, the amount of heat absorbed by the gas between the heater 5a and the temperature measuring metal layer can be detected more accurately, and a more accurate degree of vacuum can be obtained.

  Further, the recess 4 has a square shape in plan view, the heater 5a is provided at a position close to the first inner wall 4a or the first inner wall 4a on the bottom surface, and the temperature measuring metal layer 5b faces the first inner wall 4a. The second inner wall 4b or the bottom second inner wall 4b is preferably provided at a position close to the second inner wall 4b. With this configuration, the space between the heater 5a and the temperature measuring metal layer 5b is large, and the amount of gas existing between the heater 5a and the temperature measuring metal layer 5b is large. The amount of heat absorbed by the gas between the metal layer and the metal layer can be detected more accurately, and a more accurate degree of vacuum can be obtained.

  Further, as in the example shown in FIG. 2, the getter 9 provided on the bottom surface or the inner wall of the recess 4 and spaced from the heater 5a and the temperature measuring metal layer 5b, and the outer surface of the insulating base 6 are provided. It is preferable to have a getter terminal 9a connected to the. With such a configuration, when the degree of vacuum in the recess 4 is detected by the vacuum sensor 5 and the vacuum state is not present (low vacuum), a current is supplied from the outside to the getter 9 via the getter terminal. Is applied to heat the getter 9 to activate the getter 9 and adsorb gas molecules in the recess 4 to the getter 9 to increase the degree of vacuum.

The getter 9 is preferably provided at a position not sandwiched between the heater 5a and the temperature measuring metal layer 5b in a plan view, and is disposed at a position as far as possible from the heater 5a and the temperature measuring metal layer 5b. More preferred. More specifically, as in the example shown in FIG. 2A, the heater 5a is provided at a position near the first inner wall 4a or the first inner wall 4a on the bottom surface, and the temperature measuring metal layer 5b is the first inner wall 4a. The second inner wall 4b facing the inner wall 4a or the second inner wall 4b on the bottom surface is provided at a position close to the inner wall 4a, and the heater 5a and the temperature measuring metal layer 5b are connected to the first inner wall 4a and the second inner wall 4b.
Preferably, the getter 9 is provided at a position close to the fourth inner wall 4d facing the third inner wall or the fourth inner wall 4d on the bottom surface. Since the heater 5a and the temperature measuring metal layer 5b are separated from the getter 9, a more accurate degree of vacuum can be obtained.

  The heater 5a and the temperature measuring metal layer 5b constituting the vacuum sensor 5 are made of platinum or the like, for example, and can be formed on the bottom surface or inner wall of the recess 4 of the insulating base 6 as follows. First, a conductive paste for a vacuum sensor 5 obtained by adding and mixing an appropriate organic binder and solvent to platinum metal powder is printed in a predetermined pattern on a ceramic green sheet to be an insulating substrate 6 in advance by a screen printing method or the like. By coating and firing at the same time as the ceramic green sheet to be the insulating base 6, it is deposited on the bottom surface or inner wall of the recess 4 of the insulating base 6.

  In addition, about the conductor paste used as the heater 5a and the metal layer 5b for temperature measurement, you may make it print in multiple times, without printing to predetermined thickness by one printing. Further, after each printing, the printed conductor paste may be pressurized.

  On the outer surface of the insulating base 6, a heater terminal 8 a that is electrically connected via the heater 5 a and the through conductor 7, a temperature measuring metal layer 5 b and a measurement that is electrically connected via the through conductor 7. A temperature terminal 8b is provided. The heater terminal 8a and the temperature measuring terminal 8b are provided on the surface (lower surface) opposite to the surface portion where the heater terminal 8a and the temperature measuring terminal 8b are provided on the surface of the insulating base 6, for example. Yes. The heater 5a, the temperature measuring metal layer 5b, the heater terminal 8a, and the temperature measuring device are not limited to the through conductor 7 but via a wiring conductor layer (not shown) provided inside or on the surface of the insulating substrate 6. The terminal 8b may be connected.

  The wiring conductors such as the heater terminal 8a, the temperature measuring terminal 8, and the through conductor 7 may be made of platinum or the like, for example, like the heater 5a and the temperature measuring metal layer 5b, or may be made of other metal materials. . This metal material is, for example, a platinum iridium alloy, tungsten, molybdenum, niobium, silver, palladium, or the like, and is preferably a material that can be fired simultaneously with the ceramic green sheet serving as the insulating substrate 6.

  The through conductor 7 is formed by, for example, mechanical punching processing or laser processing or the like on a ceramic green sheet to be the insulating base 6 to provide a through hole, and the metal material conductor paste as described above is provided in the through hole. And then co-firing.

  Further, external electrodes for electrically connecting the package 1 to an external electric circuit are provided on the outer surface such as the lower surface or the side surface of the insulating base 6, and a conductive path formed in the package 1 is connected thereto. Yes. The external electrode is produced by the same material and forming method as the heater 5a and the temperature measuring metal layer 5b.

The exposed surfaces of the heater 5a, the temperature measuring metal layer 5b, the heater terminal 8a, the temperature measuring terminal 8b, the external electrode and the wiring conductor layer are further coated with a metal plating layer by an electrolytic plating method or an electroless plating method. ing. The metal plating layer is made of a metal having excellent corrosion resistance such as nickel, copper, gold or silver, and connectivity with a connection member. For example, a nickel plating layer having a thickness of about 0.5 to 5 μm and a gold of about 0.1 to 3 μm A plating layer, or a nickel plating layer having a thickness of about 1 to 10 μm and a silver plating layer having a thickness of about 0.1 to 1 μm are sequentially deposited. Accordingly, corrosion of the heater 5a, the temperature measuring metal layer 5b, the heater terminal 8a, the temperature measuring terminal 8b, the external electrode and the wiring conductor layer can be effectively suppressed, and the bonding between the external electrode and the external electric circuit can be suppressed. Can be strengthened.

  Moreover, you may interpose the metal plating layer which consists of metals other than the above, for example, a palladium plating layer.

  The getter 9 uses a chemically active member. For example, a metal having titanium (Ti), zirconium (Zr), iron (Fe), and vanadium (V) as main components can be used. A getter mounting electrode (not shown) is provided on the bottom surface of the recess 4, and the getter 9 is joined thereon using a brazing material or the like. The getter mounting electrode is electrically connected to the getter terminal 9 a by the through conductor 7. Further, the getter terminal 9a is similarly formed of the same material as the heater 5a and the temperature measuring metal layer 5b, and is similarly coated with a metal plating layer.

  For example, an infrared sensor, a solid-state imaging element, a semiconductor element such as a light emitting element, or an electronic component 11 such as a crystal diode, a semiconductor laser diode, or a photodiode is mounted on the vacuum sensor 5 of the package 1. It becomes an electronic device.

The electronic device can be manufactured by the following process. First, the electronic component 11 is mounted on the mounting portion 3 of the package 1 described above. When the electronic component 11 is fixed, an electrode of the electronic component 11 and a connection electrode (not shown) provided on the mounting portion 3 are mainly connected. For this connection, a connection method such as flip-chip connection using a bump or wire bonding using a gold wire may be used.

  Next, the lid 2 is joined to the insulating base 6 so as to close the recess 4 of the package 1 on which the electronic component 11 is mounted, and the space in the recess 4 is hermetically sealed. The lid 2 is a plate or cap made of metal, ceramics, glass, resin or the like. The lid 2 preferably has a thermal expansion coefficient close to that of the insulating base 6 constituting the package 1. For example, the insulating base 6 is made of an aluminum oxide sintered body, and a lid 2 made of metal is used. In some cases, an Fe-Ni (iron-nickel) alloy, an Fe-Ni-Co (iron-nickel-cobalt) alloy, or the like may be used. When the electronic component 11 is a solid-state imaging device or a light emitting device, the lid 2 is not only made of a light transmissive plate made of glass, resin, etc., but also a light transmissive lens made of glass, resin, etc. Or you may use the cover body 2 to which the lens was attached.

  The package 1 and the lid 2 are joined using a sealing material such as a brazing material. A sealing metal layer to which a sealing material is bonded is provided on the upper surface of the insulating base 6 around the recess 4 of the package 1. As the sealing material, for example, a preformed material, a material clad on the lid 2 or a paste material can be used. Moreover, such a sealing material may be arrange | positioned in the joining surface of the package 1 and the cover body 4, and joining of the package 1 and the cover body 2 by the printing method using the paste-form sealing material. It may be arranged on the surface. Then, the sealing material disposed on the joint surface between the package 1 and the lid body 2 is heated and melted using an infrared lamp heater, a heater block, a heater plate, or the like, so that the package 1 and the lid body 4 Can be bonded via a sealing material.

  At this time, by joining the lid body 2 in a vacuum, an electronic device in which the space in the recess 4 is sealed in a vacuum state is obtained. And since the package 1 of this embodiment has the heater 5a and the metal layer 5b for temperature measurement in the recessed part 4, after sealing the recessed part 4, it is checked whether the space in the recessed part 4 is a vacuum state. Can be inspected.

As described above, the vacuum state inspection is performed by connecting a power source to the heater terminal 8a to raise the temperature of the heater 5a, and connecting a temperature measuring device to the temperature measuring terminal 8b to connect the gas on the temperature measuring metal layer 5b. And a device for measuring the voltage and current to be applied to cause the heater 5a to generate heat is connected to the heater terminal 8a, and the change in voltage is measured while keeping the current constant.

  This inspection can remove an electronic device having a low degree of vacuum. When the package 1 includes the getter 9 and the getter terminal 9a described above, the getter 9 is activated by connecting the power source to the getter terminal 9a of the electronic device with a low degree of vacuum and heating the getter 9, The gas in the recess 4 can be adsorbed. Thereby, the vacuum degree in the recessed part 4 can be raised. Thereafter, the inspection of the degree of vacuum is performed again, and the electronic device with the increased degree of vacuum can be made a non-defective product.

  The electronic device thus manufactured is used as a component mounted on various electronic devices such as various sensors, computers, and communication devices. This mounting is performed by mounting the electronic component 11 on the upper surface of the insulating base and electrically connecting the external electrode to a conductive connecting material such as a brazing material.

DESCRIPTION OF SYMBOLS 1 ... Package 2 ... Cover body 3 ... Mounting part 4 ... Recess 4a ... 1st inner wall 4b ... 2nd inner wall 4c ... 3rd inner wall 4d ... 4th inner wall 5 ... Vacuum sensor 5a ... Heater metal layer 5b ... Temperature measuring metal layer 6 ... Insulating substrate 8a ... Heater terminal 8b ... Temperature measuring terminal 9 ... Getter 9a ... Getter Terminal

Claims (5)

An insulating substrate having a recess;
A mounting portion provided on a bottom surface of the concave portion on which an electronic component is mounted;
A heater provided on the bottom or inner wall of the recess;
A metal layer for temperature measurement provided on the bottom surface or inner wall of the concave portion apart from the heater;
A heater terminal provided on the outer surface of the insulating base and connected to the heater;
A package having a temperature measuring terminal provided on an outer surface of the insulating base and connected to the temperature measuring metal layer.   2. The package according to claim 1, wherein the heater and the temperature measuring metal layer are provided at positions where the heater and the temperature measuring metal layer do not sandwich the mounting portion in a plan view. The recess is rectangular in plan view,
The heater is provided at a position close to the first inner wall or the first inner wall of the bottom surface,
3. The package according to claim 2, wherein the temperature measuring metal layer is provided at a position close to the second inner wall of the second inner wall facing the first inner wall or the second inner wall of the bottom surface.   A getter provided on a bottom surface or an inner wall of the concave portion apart from the heater and the temperature measuring metal layer, and a getter terminal provided on an outer surface of the insulating base and connected to the getter. The package according to any one of claims 1 to 3, characterized in that: A package according to any one of claims 1 to 4;
The electronic component mounted on the mounting portion;
An electronic device comprising: a lid that seals the recess.

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