JPS6016087B2 - Manufacturing method of particulate resistive film element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a resistance element in which a fine particle resistance film is formed on an insulating substrate, and an object of the present invention is to provide a manufacturing method that allows the resistance value to be easily and accurately adjusted. be.

It is desired to realize a resistor element made of a resistor thin film with a large sheet resistance in order to reduce the size of the resistor element as a resistor element for a thin film circuit or a resistor element for an individual resistor.

Thin film resistive materials conventionally known to have high sheet resistance include Cr-Sj○cermet, which has a sheet resistance of 30 to 10,000/piece, and 1,000/piece to 100K.
Although there are Ta-glass cermets having a sheet resistance of Q/□, these are still insufficient. Therefore, prior to the present invention, a new high-area resistance element was devised that could have a larger area resistance than those of the conventional ones.

The resistive element is manufactured by depositing fine particles made by evaporating a conductive material in an inert gas onto the substrate to form a fine particle resistive film. be. When a conductive substance, such as a metal, is evaporated in an inert gas, fine particles with a much larger particle size than in the case of normal vacuum evaporation can be obtained.
"Applied Physics" 1972 Wang November issue No. 1067-1085
It is known from pages etc.

The inventors succeeded in producing a microparticle resistance film with a sufficiently large sheet resistance by depositing the microparticles thus obtained on an insulating substrate. At present, it is not fully understood why such a fine particle film has a high area resistance, but when the fine particles are deposited on a Zetsurishi substrate, resistance occurs at the contact interface between the fine particles, and this It is thought that the resistance of the fine particles themselves are equivalently connected in series, and the whole shows a high area resistance.

In such a particulate resistance film, the sheet resistance value can be set by changing the diameter of the deposited particulates.

There are various ways to change the diameter of fine particles, such as changing the evaporation temperature, the type or composition of the inert gas as the atmospheric gas (the heavier the gas, the larger the particle size), and even changing the gas pressure. I can think of things. Among these, a particularly effective means is to change the gas pressure of the inert gas. As an example, when the average particle size of nickel (Ni) made into fine particles by an in-gas evaporation method using argon (Ar) gas was observed using a transmission electron microscope, it was found that when the gas pressure of Ar gas is ITom, There is a range of 0.8≦p≦20 between the particle size do of the Ni fine particles and the particle size d of the Ni fine particles when the gas pressure is PTom = 110
It was recognized that there was a relationship of &, and it was confirmed that fine particles with a desired particle size could be obtained by appropriately adjusting the gas pressure.

When the gas pressure is changed in this way,
The area resistance value of the particulate resistive film, for example, in the resistive element obtained in the example described later, changes according to the characteristics shown in Fig. By doing so, the resistance value can be changed from 1 to 1 to 3Q, and the area resistance value at this time can also be changed over a range of 10-3 to 1 to Q'□ and 1q orders of magnitude.

In this way, if you control it by gas pressure,
The control range of the area resistance value can be widened sufficiently, and the simple operation of just changing the gas pressure of the inert gas makes it possible to
There is an advantage that the sheet resistance value can be controlled relatively easily. Next, an embodiment of the method for manufacturing a localized area resistance element according to the present invention will be described in detail.

First, FIG. 1 shows an example of its structure, and in the figure, 1 is an insulating substrate on which a predetermined pattern of electrodes 2 are formed, and is made of, for example, glass, forsterite porcelain, alumina porcelain, glazed alumina porcelain, Berilla, etc. . Further, the electrode 2 can be selectively formed on the insulated substrate 1 by any method among the methods described below. (A) An AI thin film or Ta-Au thin film is formed on a glass substrate to a thickness of about 3000 Å by direct current sputtering through a mask.

'o} A two-layer thin film of Cr and Au is formed on a glass substrate by resistance heating vapor deposition. First, an Ag-Pd based conductive paste is printed and fired on an alumina ceramic substrate.

0 After forming the terminal portion of the alumina ceramic substrate using frit silver, an Au terminal is formed over a part of the terminal portion.

[Mura] Ni-Cr (300 A) and Au (3
A two-layer thin film of 000A) is formed by vacuum evaporation.

N On a glass substrate or glazed alumina porcelain,
A two-layer thin film of C and Pd is formed.

Kawa: It is formed by applying an Au conductive paste onto a forsterite porcelain substrate and firing it. Further, reference numeral 3 denotes a particulate resistance film, which is formed by adhering particulates of a conductive substance such as Ni, made by evaporation in an inert gas, etc., onto the insulating substrate 1, and the end thereof is the end of the electrode 2. It is made so as to straddle the resistive element, forming a resistive element.

Next, an example of a method for manufacturing such a resistance element will be described with reference to FIGS. 2 and 3. FIG. 2 is a diagram for explaining the manufacturing process, and FIG. 3 shows the configuration of the manufacturing apparatus.

First, an insulating substrate 1 is prepared, and electrodes 2 of a predetermined pattern are formed on the surface of the insulating substrate 1 (FIG. 2A) by the above-mentioned means (a second
Figure B).

This substrate 1 is fixed to the upper part of the belljar 4, and a through hole 5 is formed across the exposed surface of the insulating substrate 1 and the end of the electrode 2 so as to form a particulate resistance film 3 over the end of the electrode 2. Form it, remove it, and attach the plate 6 (Fig. 2C). In addition, a heating board 7 is provided at the bottom of the bell jar 4,
A conductive material 8 such as Ni is layered. A shirt cover 9 is provided between the insulating substrate 1 and the conductive material 8 and kept closed. Exhaust air from the exhaust port 10 using a vacuum pump, energize the board 7 to generate heat, and release gas from each part, and then supply an inert gas, for example ~ gas, from the inert gas inlet 11 for cleaning. , and further exhaust the air through the exhaust port 10. At this stage, the inside of the bell jar 4 is evacuated to a degree of vacuum of 10-7 tons or more. Next, inert gas inlet 1 1 to 9
A high purity inert gas such as argon of 9.9999% or more is supplied and sealed until a predetermined gas pressure is reached.

The gas pressure at this time is determined in accordance with the desired sheet resistance value in accordance with the characteristics shown in FIG. 4, which will be described later. after that,
Electricity is applied to the board 7 from a heating power source 12 to heat the board 7, thereby heating the conductive material 8 and generating fine particles 13 thereof. After the generation condition stabilizes, open the shirt cover 9, dry it, and pour the fine particles 13 through the through hole 5 of the plate 6 onto the ends of the insulating substrate 1 and the electrode 2.
is deposited to form a particulate resistance film 3 (FIG. 2D).
When the predetermined adhesion time ends, the shirt cover 9 is closed again, the power supply 12 is cut off, and the power supply to the board 7 is stopped. Then, an inert gas Z is further supplied from the inert gas inlet 11 for cooling, and the particulate resistance film 3 is formed. In such a manufacturing process, Ar gas is used as an inert gas,
Using Ni as the conductive material 8, a tungsten Z boat with a resistance value of about 10 mQ as the heating board 7, and a maximum voltage W as the heating power source 12, the shirt cover 9 is opened to release the particles 13. FIG. 4 shows an example of actual measurement of the resistance value of a resistor element manufactured by increasing the deposition time of the particulate resistive film to about 15 minutes.

Here, the axis is the gas pressure of Ar gas sealed in the bell gear 4 when forming the particulate resistance film 3, and the vertical axis is the resistance value. As is clear from this characteristic diagram, by adjusting the gas pressure of the inert gas sealed when the conductive material 8 is evaporated into the fine particles 14, the area resistance value of the resistance element can be arbitrarily changed over a wide range. You can choose. Also, the area resistance value of this resistance element is approximately 10-3 to 10-10 depending on the gas pressure.
70/□, it is possible to obtain a much larger area resistance value than conventional ones, and it can greatly contribute to the miniaturization of resistive elements for thin film circuits and other applications. Also, it is possible to make products with small area resistance values.
The range of application can be extremely widened. In addition, Ni
It goes without saying that the particulate resistive film 3 can be made using various other conductive substances as the evaporation material, and any inert gas other than Ar gas can be used as the atmospheric gas. .

As described above, a particulate resistive film element is fabricated. However, simply attaching the particulate resistive film 3 to the end of the electrode 2 in such a way as to overlap it will result in a problem of contact resistance between the two, especially in high-resistance elements. It may become.

In such a case, a conductive material of the same type or different type is sufficiently added to the overlapping portion of the two by ion plating to make the particulate resistive film 13 in this portion completely conductive and to bring it into close contact with the electrode 2. Just do it like this. In FIG. 3, 15 is a cathode for performing high-frequency excitation type ion plating, 16 is a ring-shaped high-frequency crab pole, 17 is a high-frequency power source for ion plating of, for example, 13.5 mm, and 18 is a high-frequency power source for ion plating. Power source for acceleration, 19 is a shield for regulating the ion plating position,
It is a board. With this configuration, the ring-shaped high frequency electrode 1
6 is placed above the conductive material 8, a plate 19 is placed above the conductive material 8, Ar gas is introduced to generate a high-frequency glow discharge, thereby maintaining plasma, and the evaporation material is heated by a tungsten boat 7. 8 is ionized to form evaporation material ions 20, which are then applied to the resistive film 4 through the plate 19 to form a conductive region 3' (FIG. 2E).

This ion plating is one of the inert gases such as gases.
It operates stably at relatively low gas pressures of about 0-3 to 10-4 Tom. In the vacuum evaporation method, even if the temperature of the boat 7 is 230 pK, the energy of the evaporated Ni is about 0.2V, and even in the sputtering evaporation method, it is several eV to 10$V, whereas in the ion plating method, the energy of evaporated Ni is about 0.2V. AEON 20
Since it is possible to give a large energy of several 1 to 2 eV to the resistive film 3, by adding ions of such a high-energy conductive material to the resistive film 3, the conductive region 3' is formed, and the conductive region 3' is formed with very good adhesion. The resistive film 3 can be adhered to the electrode 2.

Furthermore, in the ion plating method, the surface is cleaned by sputtering due to ion bombardment, and this is considered to also contribute to improving the conductivity and adhesion between the two. It goes without saying that the evaporation material for performing such ion plating may be the same as the conductive material 8 used as the evaporation material for forming the particulate resistive film 3, or a different material may be used. . Furthermore, when performing ion plating, it is necessary to change the structure and arrangement of the cathode 20 so that the ions 20 of the conductive material are effectively added to the area where the particulate resistive film 3 and the electrode 2 overlap. Even better. Furthermore, when a conductive substance is added by such ion plating, the resistance of the particulate resistive film 3 to which it has been added decreases, and it eventually becomes a conductive region 3', which increases the resistance. The contact resistance between the electrode 2 and the portion that operates as a contact electrode is significantly reduced, and a good connection is achieved.

After that, air is introduced from the air introduction port 14 and cooled,
By removing the plates 6 and 19 and taking out the insulating substrate 1 and the like, the process of forming the resistive element film itself is completed. In this way, it is possible to fabricate a resistive element using a particulate resistive film, but it is quite difficult to maintain various conditions at predetermined settings even with the above-described manufacturing method.

In particular, it is difficult to maintain the gas pressure at a predetermined value in the process of evaporating the conductive material 8 into fine particles 13 in an inert gas atmosphere and adhering them to the insulating substrate 1 to form the fine particle resistance film 3. The resistance value of the produced particulate resistive film 3 may have a considerable error. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a manufacturing method that can easily and accurately adjust the resistance value of a resistive element made of such a particulate resistive film.

Therefore, the present invention is characterized in that ion plating of a conductive material is used as a means for adjusting the resistance value. An embodiment of the method of the present invention will be described below with reference to FIGS. 2 and 3. Note that the following adjustment step is performed after the step shown in FIG. 2E in which the conductive region is formed. First, as shown in FIG. 3, the plate 6 is made of metal and brought into contact with the electrode 2 on the insulating substrate 1, and the electrode 2 is electrically drawn out to the outside. The resistance value of the particulate resistance film 3 is measured by connecting it to a suitable resistance meter 21 while the particulate resistive film 3 remains installed in the bell jar 4. This resistance value measurement is continued until the adjustment is completed. The shield and plate 19 for the conductive region manufacturing process are removed. Then,
The inert gas is exhausted from the exhaust port 10, and the inert gas is filled with a gas pressure of about 10-3 to 4 Torr, which is suitable for ion plating. Thereafter, the high frequency power source 17 and the high voltage power source 18 are connected, and the board 7 is energized to heat and evaporate the conductive material 8 to form ions 20 of the conductive material 8. Then, the shirt plate 9 is opened, this is added to the particulate resistance film 3, and ion plating is performed (FIG. 2F). When ions 20 are added by ion plating, the resistance value of the particulate resistive film 3 gradually decreases, so when the resistance value measured by the resistance meter 21 reaches a predetermined value, the shirt cover 9 is closed and the board 7 is closed. heating and power supply by the high frequency power source 17 and high voltage power source 18 are stopped to stop ion plating. The above particulate resistance film is
Even when formed using the same material, the resistance value differs depending on the pressure of the inert gas at the time of formation.

For example, by simply changing the argon gas pressure by about 20 pm to 0.1 to 2 mon, the area resistance value of the particulate resistive film obtained is 10-3 to 1070/mouth, which is unlike anything previously obtained from a low area resistance value. The resistance value changes by a factor of 1 and 10 at a high area resistance value. This is based on the fact that the area resistance value of a particulate resistive film can be controlled by controlling the average particle diameter of the particulates constituting the particulate resistive film. The structure of the particulate resistance film also changes from columnar to porous columnar to cavernous as the inert gas pressure is varied from 0.1 to 2 orr.

In this way, particle resistive films have properties that are completely different from conventional thin and thick films.

The film density is two to three orders of magnitude smaller than that of conventional dense films. When the pus density is low, there are fewer contact interfaces between fine particles, so the sheet resistance becomes higher. As is clear from the above, the fine particle film structure of the present invention is significantly dependent on the manufacturing conditions of the film, and it has been confirmed through experiments that the resistance can be controlled to the same value regardless of the type of evaporation material or inert gas. .

When a porous microparticle resistance film is ion-plated with a conductive material, its resistance decreases.

Because it is a porous membrane, the conductive material is not only on the membrane surface.
It is even introduced inside. The depth of introduction is also related to the acceleration energy of ion plating. As mentioned above, the main factor that determines the resistance value of a particulate film is the contact interface between the particulates that make up the film, so when a conductive substance is attached thereto, the sheet resistance changes. Depending on the amount of adhesion,
The sheet resistance value changes. If the resistance value is adjusted by ion plating in this manner, the adjustment can be performed extremely easily, and moreover, an accurate resistance value can be obtained.

Furthermore, since adjustments can be made without taking the bell jar 4 out, the process can also be simplified. In addition, if the resistance value is made too small when performing the resistance value by ion plating in this way, or if the resistance value is manufactured with too small a value from the beginning, the particulate resistance value will be reduced as shown in Figure 3. A heater 22 capable of heating the film 3 and its power supply 23 are provided, and the particulate resistance film 3 is heated and oxidized in an atmosphere containing a small amount of oxygen in the bell jar 4.

Since the resistance value of the particulate resistive film 3 gradually increases when it is oxidized, heating may be stopped when the resistance value reaches a predetermined value while being measured using the resistance meter 21. Heater 2
2 is an insulating substrate holder 24 to which the cathode 15 is attached;
In addition, to introduce oxygen, pure oxygen or air containing oxygen may be introduced. Furthermore, if the particulate resistance film 3 produced as described above is used in the air as it is, there is a risk that it will be oxidized by air and moisture and deteriorate over time.

In order to prevent such deterioration, as shown in Figure 5,
An insulating protective layer 2 is formed on at least the surface of the particulate resistive film 3.
5 should be set. As this protective layer 25, Si
A vapor deposited film of ◯, a silicon resin coating film, a double film of an SiO vapor deposition film and a silicon resin coating film, an SiO2 film formed by RF sputtering, a resin film, etc. can be used. For example, when using a vapor deposited film such as Si○ as the protective layer 25 and performing the vapor deposition during the process of forming the resistor element, in the apparatus shown in FIG. 3, the boat 7, the conductive material 8
Separately, a board on which an insulating material such as Si○ is layered is prepared in the same way (not shown), and before the above-mentioned air introduction step for extraction, an exhaust The air is evacuated from the port 10 to create a vacuum, a shield and a board are attached to determine the location where the protective layer 25 is to be formed, and then the boat on which the insulator vapor deposition material is spread is energized and heated to form the particulate resistive film 3. A protective layer 25 is formed by depositing an insulating material such as Si○ on the surface, and then the shield and plate are removed.
All you have to do is stop the exhaust and introduce air.

As described above, according to the present invention, the resistance value of a novel particulate resistive film element capable of obtaining a high area resistance can be easily and accurately adjusted and manufactured.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a resistive film element devised prior to the present invention, and Fig. 2 A, B, C, D, E, and F are steps of an example of implementing the method for manufacturing a microparticle resistive film element of the present invention. A cross-sectional view of the resistive film element in the middle, Figure 3 is a cross-sectional view of the equipment used for the same type of work,
FIG. 4 is a characteristic diagram showing the gas Shoichi resistance value characteristics of a resistive film element manufactured in the same process, and FIG. 5 is a cross-sectional view of the resistive film element provided with a protective layer. 1... Insulated fog substrate, 2... Electrode, 3...
・Particle resistance film, 4... Belgear, 5...
・・Through hole, 6 ・・Shiyahei plate, 7 ・・・Boat, 8 ・・・Conductive material, 9 ・・・Shirt cover, 10 ・・・・Exhaust port, 11...Inert gas inlet, 12...Heating power supply, 13...
Fine particles, 14...Air inlet, 15...
・Cathode, 16...High frequency electrode, 17...
・High frequency power supply, 18... High voltage power supply, 19... Shiyahei plate, 20... Ion, 21... Resistance meter,
22... Heater, 23... Power supply, 24...
・・・・・・Excellent board holder, 25・・・・・・Protective layer. Figure 1 Figure 5 Figure 2 Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1. Manufacturing of a particulate resistive film element characterized in that the resistance value is adjusted by adding a conductive substance to a particulate resistive film made of fine particles of a conductive substance adhered to an insulating substrate by ion plating. Method. 2. Evaporate the conductive material in an inert gas atmosphere to create fine particles, deposit the fine particles on an insulating substrate to form a fine particle resistance film, and then reduce the pressure of the inert gas and ion plate the conductive material. 2. The method of manufacturing a particulate resistive film element according to claim 1, wherein the particulate resistive film element is added to the particulate resistive film to adjust the resistance value. 3. A method for manufacturing a fine particle resistive film element according to claim 1 or 2, characterized in that the same material is used as the conductive material for forming the fine particles and the conductive material for ion plating.