JPH1131289A - Transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmitter high in reliability even under high- temperature and high-level radiation irradiation. SOLUTION: In a transmitter for converting a measured signal from a measuring equipment into a normalized and unified transmission signal, and outputting it, one part of an electronic component 1 constituting the signal processing circuit part of the transmitter is integrated into an environment resistant type hybrid IC whose heat resistance and radiation resistance is excellent. This environment resistant type hybrid IC is constituted so that a substrate 2 on which one part of the electronic component 1 constituting the signal processing part is mounted can be stored in an air-tightly sealed inside package 11, and the inside package 11 can be stored in an outside package 14 constituted of a radiation shielding member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitter used under high temperature and high radiation.

[0002]

2. Description of the Related Art In an instrumentation system, a transmitter connects a measuring instrument and a receiver, converts a primary measurement signal from a detector into a transmission signal of a standardized format, and converts the primary measurement signal into a receiver (indicator, indicator).
Recorder, etc.). Conventionally, transistors, ICs,
Electronic components such as LSIs have been directly incorporated on a substrate like other circuit units.

[0003]

Conventionally, electronic components constituting a signal processing circuit section of a transmitter have been directly mounted on a substrate. However, when the transmitter is installed under irradiation of high temperature and high radiation, there is a problem that the heat resistance and radiation resistance of the electronic component are low, so that a failure occurs or an error increases. In addition, there is a problem that the transmitter cannot be used due to many failures and large errors. An object of the present invention is to provide a highly accurate and highly reliable transmitter even under environmental conditions where high temperature and high level radiation are irradiated.

[0004]

A transmitter according to the present invention is configured as follows. (1) A transmitter for converting a measurement signal from a measuring device into a transmission signal and outputting the converted signal to the outside, wherein a part or all of a signal processing circuit unit provided for conversion of the transmission signal is provided. It is incorporated in an environment-resistant hybrid IC having heat resistance and radiation resistance. (2) In the transmitter according to (1), the environment-resistant hybrid IC is hermetically sealed by storing a substrate in which a part or all of the signal processing circuit unit is incorporated, and storing the substrate. It is characterized by including an inner package and an outer package made of a radiation shielding material and storing the inner package. (3) The transmitter is a differential pressure transmitter or a pressure transmitter. (4) As the IC constituting the transmitter circuit, an IC having excellent radiation resistance is selected based on information on the structure and process of the IC itself, and the amount of change in various electrical characteristics due to irradiation of the IC is determined by the lot of the IC. It is selected in consideration of variations. (5) An environment-resistant hybrid IC in which a part or all of a transmitter circuit is incorporated is formed on a metal base substrate formed by laminating an insulating layer and a wiring pattern on a metal base of Ti or W-based material. Has been implemented. (6) The circuit of the transmitter is designed based on the fluctuation data of the electric parameters of the electronic components used in the circuit alone, and the circuit and the system are designed to improve the radiation resistance as a circuit block. The design is performed in consideration of the characteristic change due to radiation.

An embodiment of an environment-resistant hybrid IC package in which a part or all of a signal processing circuit of a transmitter is incorporated will be described below. (7) A metal package in which a material such as Fe or Ni is compounded with a W-based material as a base material and hermetically sealed. (8) An internal package in which some or all of the electronic components of the signal processing circuit of the transmitter are mounted and hermetically sealed;
An external package that stores the internal package and is made of a radiation shielding material. (9) A board on which a part or all of electronic components of a signal processing circuit of a transmitter is mounted or a circuit is mounted,
A hermetically sealed inner package, a first outer package containing the inner package and made of a radiation shielding material, and a second outer package containing the first outer package and made of a radiation shielding material Have. (10) The external package is made of a radiation shielding material for shielding gamma rays of heavy metals such as a tungsten alloy, a lead alloy, a molybdenum alloy, a copper alloy, a nickel alloy, a cobalt alloy, and an iron alloy. (11) The external package is made of a radiation shielding material for shielding neutron rays, such as a carbon compound containing light elements, a boron compound, a metal hydroxide compound, or a ceramic. (12) In the above (9), the first external package is made of the radiation shielding material for shielding γ rays described in the above (10), and the second external package is radiation for shielding the neutron rays described in the above (11). Made of shielding material.

[0006] The transmitter of the present invention has the following operations and effects by the above configuration. Part or all of electronic components such as a transistor, an IC, and an LSI, which are weak to radiation, constitute a signal processing circuit unit of a transmitter, and are incorporated in an environment-resistant hybrid IC excellent in heat resistance and radiation resistance. An environment-resistant hybrid IC has a configuration in which a substrate on which a signal processing circuit is incorporated is stored in a hermetically sealed package, and prevents internal electronic components from being heated to a high temperature. Enable operation. For example, according to an experiment by the inventor, when a hybrid IC is stored in a package that is not hermetically sealed, circuits inside the package cannot operate at all at a high temperature of 100 ° C. or higher. On the other hand, when the circuit was stored in a hermetically sealed package, the circuit inside the package could operate for 5 hours or more at a high temperature of 150 ° C. Further, the environment-resistant hybrid IC has a configuration stored in a package made of a radiation shielding material. Since radiation is shielded by the package made of the radiation shielding material, the electronic components stored inside are irradiated with the radiation. Operation can be performed even under high radiation. Therefore, the transmitter of the present invention is highly accurate and reliable even in harsh environments exposed to high levels of radiation and exposed to high temperatures.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a perspective view showing an environment-resistant hybrid IC in which a part of a signal processing circuit section of a transmitter according to a first embodiment of the present invention is incorporated. FIG. 2 is a three-view drawing of an environment-resistant hybrid IC in which a part of the signal processing circuit of the transmitter is incorporated. 2A is a front view of the transmitter, FIG. 2B is a side view, and FIG.
Is a bottom view. A part of a signal processing circuit of a transmitter, an environment-resistant hybrid IC substrate 2 in which an electronic component 1 (for example, an IC or a resistor) that is vulnerable to heat or radiation is incorporated, is composed of a metal package base 3a and a metal package cover 3b. It is installed in the configured metal package 3. Metal package base 3a and metal package cover 3
b is hermetically sealed. It should be noted that other electronic components and other circuit portions of the signal processing circuit are not shown in the drawings.

Further, external lead pins 4 are provided on the side of the metal package base 3a to be electrically connected to the substrate 2 and to transmit and receive electric signals to and from the outside. The external lead pins 4 and the metal package base 3a are hermetically sealed. Note that the perspective view of FIG. 1 shows a state without a metal package cover. 2A to 2C.
Is covered with a metal package cover 3b so that the internal electronic components and the substrate cannot be seen.

The metal package 3 is made of a W-based material, and its workability is improved by compounding materials such as Fe and Ni. Further, in order to improve the neutron beam shielding ability, a carbon-based material may be compounded. This package material satisfies the requirements for hermeticity, noise shielding, electrical characteristics, and mass productivity.

The IC used in the signal processing circuit is I
I more resistant to radiation than information such as the structure and process of C itself
It is necessary to select C and obtain the amount of change in various electrical characteristics due to the irradiation of the IC in consideration of the variation of the IC lot. I whose effects due to radiation have been fully evaluated
C is cut out from an IC wafer, and mounted in a high density on a metal base substrate having excellent radiation resistance in the form of an IC bare chip to form a module. Here, the metal base substrate is T
This is a multi-layer substrate in which insulating layers and wiring patterns are stacked many times on an i or W-based metal base plate.

In addition, it is important to design a circuit and a system in which the radiation resistance of the circuit is improved on the basis of the variation data of the electric parameters of the electronic component alone. Design in consideration of changes. For example, if a certain variation is found to occur due to irradiation, a signal that cancels out the variation is given.
Alternatively, it is preferable to design with a margin for the total variation.

As the transmitter, there is a differential pressure transmitter or a pressure transmitter, which can be used for monitoring an accident in a nuclear power plant. Specifically, it can be applied to measure the primary coolant pressure, pressurizer pressure, pressurizer water level, and steam generator water level of a PWR plant. Also,
The present invention can also be applied to a place where a differential pressure or pressure is measured in a space environment in a space station or the like.

The transmitter of this embodiment stores an environment-resistant hybrid IC in which a part of an electronic component constituting a signal processing circuit of a transmitter circuit is incorporated in a package having excellent heat resistance and radiation resistance. By preventing the circuit from becoming hot and preventing the electronic components from being irradiated with radiation, the circuit has high accuracy, has few failures, and has high reliability.

(Second Embodiment) In this embodiment, a package for storing an environment-resistant hybrid IC different from the first embodiment will be described. FIG. 3 is a cross-sectional view of an environment-resistant hybrid IC in which a part of a signal processing circuit unit of a transmitter according to a second embodiment of the present invention is incorporated. In FIG.
A ceramic substrate or a metal base substrate 2 of an environment-resistant hybrid IC in which a part of an electronic component 1 constituting a signal processing circuit of a transmitter is incorporated is installed on an internal package base 11a. External lead pins 4 electrically connected to the substrate 2 through the wire bonding 12 extend out of the holes provided on the side surfaces of the internal package base 11a, and a gap between the internal package base 11a and the external pins 4 is formed by a hermetic glass 13 It is airtight. Here, what fills the space between the internal package base 11a and the external lead pins 4 may not be the hermetic glass 13, and any insulating material can be used as long as airtightness between the internal package base 11a and the external lead pins can be maintained. is there.

The inner package base 11a and the inner package cover 11b serving as a lid thereof are hermetically sealed by seam welding to form the inner package 11. Here, the inner package 11 is formed of a metal package (mainly Kovar) for an environment-resistant hybrid IC that can be hermetically sealed.

The inner package 11 is housed in an outer package 14 composed of an outer package base 14a made of a tungsten (W) alloy and an outer package cover 14b serving as a lid thereof. The external package base 14a and the external package cover 14
b is bonded with an adhesive 15. The gap formed between the inner package 11 and the outer package 14 is filled with an adhesive or a filler 16, and the gap between the holes formed for passing the external lead pins 4 on the side surface of the outer package is further formed. Is filled with an adhesive or a filler 17.

Here, the position of the external lead pins 4 is not limited to the side surface of the package as shown in FIG. 3, but may be the lower surface of the package as shown in FIG. 4 or the upper surface of the package. In the present embodiment, radiation is shielded by the outer package 14 made of a radiation shielding material, and the hermetically sealable inner package 11 does not cause intrusion of moisture from outside the package 11 or oxidation of the electronic component 1. Long-term reliability can be obtained. Further, since the radiation that passes through the external package 14 and the secondary radiation that is generated when the radiation passes through the external package 14 are reduced by the internal package 11, it is possible to prevent the electronic components constituting the transmitter from deteriorating. .

In this embodiment, a tungsten (W) alloy is mainly used as a radiation shielding material for γ rays. However, a lead (Pb) alloy, a molybdenum (Mo) alloy, copper (Cu)
Alloy, nickel alloy (Ni), cobalt (Co) alloy,
A material made of a heavy metal such as an iron (Fe) alloy has a high radiation shielding effect and is suitable as a radiation shielding material. Further, if the radiation shielding material is changed, it is possible to shield other types of radiation.

(Third Embodiment) FIG. 5 is a sectional view of an environment-resistant hybrid IC in which a part of a signal processing circuit of a transmitter according to a third embodiment of the present invention is incorporated. The same parts as those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The present embodiment is different from the second embodiment in that the hermetically sealable inner package 18 is made of ceramics (inner ceramic package base 18a and inner ceramic package cover 18b),
A part of the electronic component 1 constituting the signal processing circuit of the transmitter is mounted on the internal ceramic package base 18a made of the ceramic. Therefore, the substrate used in the previous embodiment is not required, and the electronic component 1 constituting the transmitter is not required to have the internal ceramic package 18.
Since it is in direct contact with the substrate, the heat radiation effect is high, so that high-density mounting is possible.

(Fourth Embodiment) FIG. 6 is a sectional view of an environment-resistant hybrid IC in which a part of a signal processing circuit section of a transmitter according to a fourth embodiment of the present invention is incorporated. The same parts as those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof will be omitted. The feature of this embodiment is that the outside of the radiation-resistant package of the second embodiment is covered with a second external package 19 including an external package base 19a and an external package cover 19b. Here, the second outer package 19 is made of a carbon compound containing light elements, a boron compound,
It is composed of a metal hydroxide compound or a radiation shielding material for shielding neutron rays such as ceramics.

The inner first outer package 14 is made of a material that blocks gamma rays, and the outer second outer package 19 is used.
By using a material that shields neutrons, a package structure that can cope with several types of radiation can be obtained. This makes it possible to shield neutrons with the second external package 19 and shield γ-rays with the first external package 14. Further, with respect to secondary radiation generated when neutrons pass through the outer second outer package 19,
The inner first outer package 14 exerts a shielding effect,
It is possible to significantly reduce the amount of radiation applied to the inner electronic component 1.

It is also possible to use the ceramic package in which the substrate and the internal package described in the third embodiment are integrated as the internal package 11. The present invention is not limited to the above embodiment. For example, in the above embodiment, the differential pressure transmitter and the pressure transmitter have been described, but other transmitters may be used.

Although a part of the signal processing circuit of the transmitter is incorporated in the environment-resistant hybrid IC in the above embodiment, the entire signal processing circuit may be incorporated. Others
Various modifications can be made without departing from the scope of the present invention.

[0025]

According to the transmitter of the present invention, by incorporating a part or all of a signal processing circuit into an environment-resistant hybrid IC having a high radiation-resistant and heat-resistant capability, errors can be increased under high radiation and high temperature. And high reliability.

[Brief description of the drawings]

FIG. 1 is an exemplary perspective view showing an environment-resistant hybrid IC in which a part of a signal processing circuit unit of a transmitter according to a first embodiment is incorporated;

FIG. 2 is a diagram showing an environment-resistant hybrid IC in which a part of a signal processing circuit unit of the transmitter according to the first embodiment is incorporated.

FIG. 3 is an exemplary cross-sectional view illustrating an environment-resistant hybrid IC in which a part of a signal processing circuit unit of a transmitter according to a second embodiment is incorporated;

FIG. 4 is an exemplary cross-sectional view illustrating an environment-resistant hybrid IC in which a part of a signal processing circuit unit of a transmitter according to a second embodiment is incorporated;

FIG. 5 is a sectional view showing an environment-resistant hybrid IC in which a part of a signal processing circuit unit of a transmitter according to a third embodiment is incorporated.

FIG. 6 is a cross-sectional view showing an environment-resistant hybrid IC in which a part of a signal processing circuit unit of a transmitter according to a fourth embodiment is incorporated.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electronic component 2 Substrate 3 Metal package 3a Metal package base 3b Metal package cover 4 External lead pin 11 Internal package 11a Internal package base 11b Internal package cover 12 Wire bonding 13 Hermetic glass 14 First external package 14a First external package base 14b First external package cover 15 Adhesive 16 Filler or adhesive 17 Filler or adhesive 18 Internal ceramic package 18a Internal ceramic package base 18b Internal ceramic package cover 19 Second external package 19a Second external package base 19b 2 external package cover

 ──────────────────────────────────────────────────続 き Continued on the front page (71) Applicant 000230940 1-6-1, Otemachi, Chiyoda-ku, Tokyo Japan Atomic Power Company (71) Applicant 000006208 Mitsubishi Heavy Industries, Ltd. 2-5-1 Marunouchi, Chiyoda-ku, Tokyo (72) Inventor Hiroyuki Namagawa 3-22 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture Inside Kansai Electric Power Company (72) Inventor Isamu Doi 2-5 Marunouchi, Takamatsu City, Kagawa Prefecture Inside Shikoku Electric Power Company (72 Inventor Himura Himura 2-182 Watanabe-dori, Chuo-ku, Fukuoka City, Fukuoka Prefecture Inside Kyushu Electric Power Company (72) Inventor Takayuki Aoki 1-6-1, Otemachi, Chiyoda-ku, Tokyo Inside the company (72) Inventor Yuichi Kondo 1-1-1, Wadazakicho, Hyogo-ku, Kobe-shi, Hyogo Prefecture Inside Mitsubishi Heavy Industries, Ltd.Kobe Shipyard (72) Inventor Ikeuchi Takeshi 1-1-1 Wadazaki-cho, Hyogo-ku, Hyogo-ku, Hyogo Prefecture Inside the Kobe Shipyard of Mitsubishi Heavy Industries, Ltd. (72) Inventor Noriko Akazawa 1200, Higashi Tanaka, Komaki City, Aichi Prefecture Mitsubishi Heavy Industries, Ltd. Nagoya Guidance Propulsion System Works

Claims (2)

[Claims] 1. A transmitter for converting a measurement signal from a measuring instrument into a transmission signal and outputting the transmission signal to the outside, wherein a part or all of a signal processing circuit section provided for conversion of the transmission signal has heat resistance and radiation resistance. A transmitter which is incorporated in an environment-resistant hybrid IC having responsiveness. 2. The environment-resistant hybrid IC comprises a substrate in which a part or all of the signal processing circuit is incorporated, an airtightly sealed internal package storing the substrate, and a radiation shielding material. The transmitter according to claim 1, further comprising an external package storing the internal package.