JP2572864Y2 - Pyroelectric infrared detector - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pyroelectric infrared detector for detecting incident energy such as infrared rays by a pyroelectric effect.

[0002]

2. Description of the Related Art A phenomenon in which the temperature rises due to irradiation of infrared rays or the like, the internal spontaneous polarization changes, and charges are induced on the surface is called the "pyroelectric effect". Organic crystals such as triglycine), Li
There is an inorganic crystal such as TaO ₃ (lithium tantalate) or a ceramic element such as PbTiO ₃ (lead titanate).

In order to detect the electric charge induced on the surface of the element, generally, electrodes are formed on both sides of the element, leads are connected to the respective electrodes, and a voltage is detected from the leads. However, the lead wire may be cut by mechanical vibration. For the purpose of eliminating such a defect, as shown in FIG. 3 , a pyroelectric body 4 having a pyroelectric effect and having a front surface electrode 2 on the front surface and a back surface electrode 3 on the rear surface.
And a support substrate 7 made of an insulating member on which a plurality of conductive patterns 5 and 6 are formed. The electrodes 2 and 3 are attached to the conductive patterns 5 and 6 by conductive adhesives 8 and 9, respectively. A pyroelectric infrared detector 1 in which the pyroelectric body 2 is fixed to the support substrate 7 by bonding is proposed (for example, Japanese Patent Publication No. 61-40930). The electric charge induced on the surface of the pyroelectric body 4 is applied to the terminals T connected to the conductive patterns 5 and 6.
Is detected through.

[0004]

However, when the electrodes 2 and 3 are formed of, for example, aluminum,
In the atmosphere of the market after it is formed and after being shipped as a product, the adhesives 8 and 9 of the electrodes 2 and 3 may be deteriorated to produce aluminum hydrate (boehmite). This aluminum hydrate is progressive and causes poor adhesion.
In addition, the conductivity may be impaired, which may cause poor conduction due to loose contact.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pyroelectric infrared detector in which the reliability of electrode connection is improved.

[0006]

In order to achieve the above object, the present invention provides a pyroelectric body having a pyroelectric effect in which a front electrode is formed on a front surface and a back electrode and an extraction electrode are formed on a back surface, A support substrate made of an insulating member having a conductive pattern formed thereon, wherein the extraction electrode is bonded to the conductive pattern with a conductive adhesive to fix the pyroelectric body to the support substrate. In the detector, the back electrode and
While being formed integrally with the extraction electrode ,
0.02 to thickness hydrate non-forming metal in of formation of 3μm
It is characterized by having been done.

[0007]

Since the extraction electrode is formed of a non-hydrated metal, the extraction electrode and the conductive adhesive can be used in a highly humid atmosphere.
Since hydrates are not easily generated on the bonding surface with the adhesive, poor adhesion and poor conduction are less likely to occur. Also, back electrode and extraction electrode
And the thickness is 0.02 to 3 μm
It is made of thin material to suppress heat conduction and allow infrared rays to escape
The thickness of the pyroelectric body (or pyroelectric element) including the electrodes
It can contribute to molding.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view of a pyroelectric infrared detector 10 according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line AA in FIG. The pyroelectric infrared detector 10 has a U-shaped front electrode 12 on a front surface 14a and two back electrodes 13 on a back surface 14b.
a and a pyroelectric body 14 having a pyroelectric effect in which an extraction electrode 13b connected (integrally formed) to each back electrode 13a is formed.
And a support substrate 17 made of an insulating member on which a plurality of conductive patterns 15 are formed. The lead electrode 13b is bonded to the conductive pattern 15 with a conductive adhesive 19 to support the pyroelectric body 14. This is a two-element type fixed to the substrate 17.

The pyroelectric body 14 is made of, for example, an organic crystal such as TGS (triglycine sulfate), an inorganic crystal such as LiTaO ₃ (lithium tantalate), or a ceramic such as PdTiO ₃ (lead titanate). Things. Also,
The surface electrode 12 is made of, for example, a nickel-chromium alloy ,
The back electrode 13a and the extraction electrode 13b are 0.02 to 3
It is made of a non-hydrate-forming metal such as nickel-chromium alloy, nickel, chromium, copper, gold, iron (Fe) and alloys thereof having a thickness of μm.

According to the pyroelectric infrared detector 10 of the above embodiment, the extraction electrode 13b bonded with the conductive adhesive is formed of a non-hydrated metal. In a humid atmosphere, the adhesive 1 of the extraction electrode 13b
Since the 9 side is deteriorated and hydrate is not easily formed, poor adhesion and poor conduction due to loose contact hardly occur.
It is possible to provide a pyroelectric infrared detector in which the connection reliability of the extraction electrode 13b is improved. Moreover, the back electrode
The extraction electrode is integrally formed with a thickness of 0.02 to 3 μm.
To avoid the poor adhesion and loose contact.
Pyroelectric body including electrodes compared to the case of adding another member
(Or pyroelectric element)
is there.

The present invention is not limited to the above embodiment,
Various modifications can be made without departing from the scope of the invention.

[0013]

According to the present invention described in detail above, hydrates are hardly formed on the bonding surface of the extraction electrode bonded with the conductive adhesive in a high-humidity atmosphere. This makes it possible to provide a pyroelectric infrared detector in which the reliability of electrode connection is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a pyroelectric infrared detector according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a sectional view of a conventional pyroelectric infrared detector.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Pyroelectric infrared detector 12 Front surface electrode 13a Back surface electrode 13b Leader electrode 14 Pyroelectric body 15 Conductive pattern 17 Support substrate 19 Conductive adhesive

Claims (1)

(57) [Scope of request for utility model registration] A pyroelectric body having a pyroelectric effect, wherein a front electrode is formed on a front surface, and a back electrode and an extraction electrode are formed on a back surface;
A support substrate made of an insulating member having a plurality of conductive patterns formed thereon, wherein the extraction electrode is bonded to the conductive pattern with a conductive adhesive to fix the pyroelectric body to the support substrate. In the infrared sensor, the back electrode
And the extraction electrode are integrally formed,
0.02 to thickness hydrate non-forming metal in of formation of 3μm
Pyroelectric detector, characterized by being.