JPH0590553A - Infrared ray detector and manufacturing method thereof - Google Patents

Abstract

PURPOSE:To enhance the yield, reproducibility and device performance while abating the noise by a method wherein a lower electrode of an infrared ray detector is formed on a supporting substrate so as to be partly in contact with an electrode pattern formed on the substrate surface. CONSTITUTION:A J-FET and an integrated circuit are formed on a P-Si substrate 11 while a source electrode 13 and a gate electrode 14 of the J-FET are provided. Next, a heat absorbent film 15 serving both as an lower electrode is formed using the photoetching step and the evaporating technology in the specified position on an insulating film 12 on the P-Si substrate surface. Next, a thin film to be an infrared ray detector 16 is formed using the coating technology furthermore, another heat absorbent film 17 to be the upper electrode is deposited using the evaporating technology. Later, the heat absorbent film 17 and the infrared ray detector 16 are patterned by the dry-etching technology using a photoresist film formed in the specified shape and position by the photoetching step as a mask so as to remove the photoresist film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared detecting device including an infrared detector formed on a supporting substrate and a manufacturing method thereof.

[0002]

2. Description of the Related Art In an infrared detector, the material of the infrared detector is generally different from the semiconductor material constituting the amplifier section for processing the signal output from the detector and the S / H circuit section. Many. Therefore, the infrared detector and its signal circuit are usually connected by some means. The most common method so far is a method of connecting the chips formed on different chips using a wire bonding technique or the like.

5 and 6 show an example of a conventional system. FIG. 5 shows that the chips, that is, the infrared detector 33 and the signal processing substrate 32, which are separately manufactured, are mounted on the base 31 and are connected by the wires 34 using the wire bonding technique as described above. It is a thing. FIG. 6 shows a signal processing board 3 which is also produced separately.
2 shows that the infrared ray detector 33 and the infrared detector 33 are connected to each other on the base 31 via the columnar electrode (paste 35).

[0004]

The signal output from the infrared detector has a very weak level, and the output impedance of the infrared detector is usually very high. It is easily affected.
That is, there is a problem that the noise level does not easily decrease in the hybrid type in which the chips described above are separately manufactured and connected. Therefore, it is an object of the present invention to provide an infrared detection device that solves the above-mentioned problems of the prior art and an effective manufacturing method therefor.

[0005]

An infrared detecting device according to the present invention is an infrared detecting device in which an infrared detector is mounted on a supporting substrate, and an electrode pattern formed at a predetermined position on the surface of the supporting substrate and this electrode. A lower electrode of the infrared detector formed on the supporting substrate in a predetermined pattern so that a part of the infrared detector is in contact with the pattern, and a layer and an upper portion of the constituent material of the infrared detector formed in the predetermined pattern so as to cover the lower electrode. And an electrode.

In the method for manufacturing an infrared detecting device according to the present invention, a thin film of an infrared material is formed on a supporting substrate, and a photolithography process and a dry etching process are used to manufacture a monolithic infrared detecting device. It is characterized by that.

[0007]

As described above, according to the present invention, when the infrared detector is manufactured, the infrared detector is formed in the monolithic type instead of the hybrid type. Excellent device performance and especially low noise can be realized.

[0008]

EXAMPLE An example of the present invention will be described below.

FIG. 1 is a structural sectional view of an infrared detecting device according to the present invention in which an infrared detecting portion is formed on a P-Si substrate 11 which is an integrated circuit substrate. 2 is also according to the present invention, and is a P-Si substrate 1 which is an integrated circuit substrate.
In order to improve the heat conversion efficiency of the infrared detecting part, the semiconductor substrate 11 located directly below the infrared detecting part is removed by an etching technique in order to improve the heat conversion efficiency of the infrared detecting part.
The cavity 18 is formed as a heat insulating structure.

A process flow chart for realizing an infrared device according to the present invention having the sectional structure shown in FIGS. 1 and 2 is shown in FIGS.
Shown in (c) and (d). A structure and a manufacturing method of an embodiment of the present invention will be shown with reference to the drawings.

First, a J-FET (a transistor other than a junction type may be formed) is formed on the P-Si substrate 11, and an integrated circuit (a driving circuit for an infrared detecting section or a detection signal processing circuit) not shown is formed. Every time, as shown in the figure, JF
The source electrode 13 and the gate electrode 14 of ET are provided.
Then, at a desired position on the insulating film 12 on the surface of the silicon semiconductor substrate 11 on which the integrated circuit is mounted, a heat absorbing film 15 (NiCr or the like) which also serves as a lower electrode is formed by a photoetching process and a vapor deposition technique to a thickness of 1000 to 2000 It is formed to a thickness of about angstrom (see FIG. 3B). Of course, instead of the silicon semiconductor substrate 11 mounting the integrated circuit, a CCD
It is obvious that a semiconductor substrate on which a device is mounted, a supporting substrate having a heat insulating structure formed thereon, a supporting substrate having an electrode pattern formed thereon and having a low thermal conductivity may be used.

Next, a thin film to be the infrared detecting portion 16 is formed to a thickness of about 1 μm to 5 μm by using a coating technique. As the thin film material to be applied, an organic polymer material exhibiting pyroelectric properties (such as a vinylidene fluoride copolymer) is used. Further, a heat absorbing film 17 (NiCr or the like) which will be the upper electrode is deposited to about 100 to 300 angstrom by using the vapor deposition technique (see FIG. 3B).

Then, a photoresist film 18 is formed in a desired shape and position by a photo-etching process (see FIG. 4).
(See (a)). Using the photoresist film 18 as a mask, the heat absorption film 17 and the infrared detecting portion 16 are patterned by the dry etching technique, and the photoresist film 18 is removed (see FIG. 4B) to obtain the structure shown in FIG. An infrared detection device having a device cross-sectional structure is obtained.

After that, if the back surface of the substrate 11 is selectively etched, the structure shown in FIG. 2 is obtained. If the heat insulation structure of FIG. 2 is adopted, the heat conversion efficiency can be further improved while having the advantage of monolithic structure.

As described above, in the manufacturing method according to the present invention, since the technology used in the ordinary silicon IC technology can be used, the manufacturing method is stable, the reproducibility is good, and the hybrid method as in the conventional example. Since it is possible to realize monolithic compared to the type, external noise when using wire bonding etc. can be made extremely small,
It is possible to provide an infrared detection device having excellent characteristics.

[0016]

As described above, according to the present invention, since the infrared detecting device is formed in the monolithic type instead of the hybrid type, it is possible to realize a very stable high yield and reproducibility by being monolithic, which is extremely excellent. Device performance and especially noise reduction can be realized.

[0017]

[Brief description of drawings]

FIG. 1 is a diagram showing a device cross-sectional structure showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a device cross-sectional structure showing a second embodiment of the present invention.

FIG. 3 is a process for realizing an apparatus according to the present invention.
It is a flowchart (first half).

FIG. 4 is a process for realizing an apparatus according to the present invention.
It is a flowchart (second half).

FIG. 5 is a diagram showing a conventional example.

FIG. 6 is a diagram showing a conventional example.

[Explanation of symbols]

11 ... P-Si substrate, 12 ... Insulating film, 13 ... Source electrode, 14 ... Gate electrode 15 ... Heat absorption film (lower electrode), 16 ... Infrared detector, 1
7 ... Heat absorption film (upper electrode)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H04N 5/33 8838-5C

Claims (4)

[Claims] 1. An infrared detection device in which an infrared detector is mounted on a support substrate, wherein an electrode pattern formed at a predetermined position on the surface of the support substrate and a predetermined pattern such that a part of the electrode pattern is in contact with the electrode pattern. A lower electrode of the infrared detector formed on a supporting substrate, a layer of a constituent material of the infrared detector formed in a predetermined pattern so as to cover the lower electrode, and an upper electrode, Infrared detection device. 2. The infrared detection device according to claim 1, wherein the support substrate is a semiconductor substrate, and an integrated circuit for signal processing or a CCD device is formed on the semiconductor substrate. 3. The infrared detection device according to claim 1, wherein a portion of the support substrate immediately below the lower electrode is removed to form a heat insulating structure. 4. A method of manufacturing an infrared detection device in which an infrared detector is mounted on a supporting substrate, wherein an electrode pattern is formed at a predetermined position on the surface of the supporting substrate,
Next, one electrode material of the infrared detector is deposited on the supporting substrate by using a vapor deposition technique, patterned into a desired shape through a photoetching process, and then the material to be the infrared detector is sputtered, coated or the like. The infrared detector and the heat absorbing film are formed into a desired film by a photo-etching process and a dry etching technique. A method for manufacturing an infrared detecting device, comprising: patterning into a pattern and further applying a voltage between the one electrode and the other electrode to perform poling.