JPS60247981A - Manufacture of electrostrictive effect element - Google Patents

Abstract

PURPOSE:To manufacture a unified solid-state element, which can be driven at low voltage, by exposing internal electrode layers in a laminated chip capacitor type laminate, in which electrostrictive materials and internal electrodes are laminated alternately, on every other layer and in the whole. CONSTITUTION:Electrostrictive materials 11 in sections in which strain is not generated and electrostrictive materials 12 in sections in which strain is generated are laminated alternately together with internal electrodes 13, 14, and a laminate is cut so that the internal electrodes 13 are exposed on one side and the internal electrodes 14 on the other side on every other layer respectively and both internal electrodes 13, 14 are all exposed on both side surfaces. Temporarily mounted external electrodes 15, 16 are applied and baked on both sides so that the electrode 15 is electrically connected to the internal electrodes 13 and the electrode 16 to the internal electrodes 14. Glass powder is attached 17 onto the internal electrodes 13, and external electrodes 21 are formed. Glass powder is also attached 17 similarly onto the internal electrodes 14 on an opposite side surface, and external electrodes are shaped.

Description

Detailed Description of the Invention (Field of Industrial Application) The method of the present invention applies to electrostrictive elements (electromechanical devices) such as drive elements and minute displacement elements that utilize the electrical and mechanical energy conversion capabilities of piezoelectric or electrostrictive materials. The present invention relates to a method of manufacturing a base.

(Prior Art) Conventionally, devices using piezoelectric or electrostrictive effects have been manufactured with structures as shown in FIGS. 1(a) and 1(b). First, a cylindrical piezoelectric or electrostrictive material 'e0.2~
Slice into 1.0 mm thick pieces and burn electrodes 2 on the top and bottom surfaces. A large number of the thin plates 1 are glued together using an adhesive 3. If necessary, use bolts or the like to sandwich and fix the top and bottom surfaces. Connect the external electrodes to each other every other layer,
By applying a DC voltage of 200V to 100V between the O terminals connected to the positive and negative external terminals 4 and 5, the element expands at a rate of about 101 in the lamination direction of the thin plates. Also, if used in a restrained state, 3.5 × 1
A stress of about 0.7 N/m2 is generated.

(Problems with the conventional technology) Although the element of this structure has the characteristics of being small, generating a large force, and having a fast response speed of about 40 μsec, it has some drawbacks. Since thin plates are made by slicing, there is a limit to the thinness of the thin plates.
Since a high voltage of about 200V to 1000V is required for driving and a thin sheet metal adhesive requires force, the total thickness of the adhesive layer with a low Young's modulus increases in inverse proportion to the thickness of the thin sheet.
It has drawbacks such as absorbing displacement and generated stress during driving and difficulty in mass production.

(Object of the Invention) The object of the present invention is to eliminate the above-mentioned drawbacks and provide a manufacturing method for stably mass-producing an integrated solid-state device that can be driven at a low voltage of 100 μm or less. Structure of the Invention) The present invention is a multilayer chip capacitor type laminate in which electrostrictive materials and internal electrodes are alternately stacked.

A step of producing a laminate having two opposing side surfaces on which internal electrode layers are exposed every other layer and two opposing side surfaces on which all internal electrode layers are exposed; Step 1 of forming an external electrode; Forming an insulator on one side of the two sides where all the internal electrode layers are exposed; forming an insulator on every other internal electrode layer and its vicinity; and forming the insulator on the other side. a step of forming an insulator on every other internal electrode layer different from the formed internal electrode layer and its vicinity; and a step of forming an insulator across the exposed internal electrode at opposing positions on each of the two side surfaces on which the insulator is formed. a step of forming one or more sets of second external electrodes to be connected;
and a step of cutting between the first and second external electrodes or between the plurality of sets of second external electrodes. Marry by method.

(Detailed explanation of II formation) By adopting the internal electrode layer, the manufacturing method of the present invention can easily narrow the distance between stain electrodes to 100 μm or less, and enable low voltage driving. As a result of becoming a solid-state device, the influence of adhesives can be removed, resulting in faster response times. Furthermore, by processing the large laminate as it is, it became possible to electrically connect 10 multi-devices at the same time, making it possible to mass produce the manufacturing method.

(Examples) The present invention will be described in detail below according to Examples. Magnesium lead niobate (Pb (Mgl/3Nbν903)
A slurry prepared by adding a small amount of organic binder to electrostrictive material pre-fired powder whose main component is lead titanate (PbTi01) and dispersing this in an organic solvent is used for manufacturing ordinary multilayer ceramic capacitors. This slurry was coated onto a Mylar film to a thickness of about 100 microns using a casting film forming apparatus and dried. This was peeled off from the film to obtain an electrostrictive material green sheet. Some of the green sheets were further screen-printed with platinum paste as internal electrodes. After stacking several hundred of these green sheets and pressing them together using a heat press, 125
This was fired at 0°C to obtain an electrostrictive material laminate. This was cut at a position where the internal electrodes were exposed on the surface every other layer, two temporary external electrodes were coated and baked, and the sides were further cut to reveal the internal parts. The electrodes were exposed. The electrostrictive material laminate thus obtained is applied to an electrophoresis method. FIGS. 2 and 3 are perspective views showing exposed end faces of the internal electrodes of this electrostrictive material laminate. A number of internal electrodes 13.14 are alternately connected to two temporary external electrodes 15.16 in each layer, and a suspension containing electrically charged glass powder is prepared in the following manner.Zinc borosilicate 30g of crystallized glass powder, 290ml of ethanol! , 5% iodine ethanol solution 1
0m1! Mix with a high-speed homogenizer. Iodine acts as an electrolyte, and the glass powder is positively charged. After applying ultrasound for 30 minutes, leave to stand for 30 minutes to remove the precipitate, and use the remaining suspension.

After covering one side of the exposed end surface of the electrostrictive material laminate with an adhesive tape to prevent it from getting wet with the suspension, the electrostrictive material laminate is submerged in a container filled with the suspension. 1c in front of the end face where you want to attach the laminate? Submerge a large stainless steel counter electrode plate at a distance of ff from the end face you want to attach. The counter electrode plate is connected to the positive terminal of a DC power source, and the temporary external electrode 16 is connected to the counter electrode to have the same potential in order to prevent the exposed portion 14 from being attached at all.

Connect the temporary external electrode shown at 15 to the negative terminal, and
Apply voltage for 300 seconds. When the suspension was removed from the suspension and dried, glass powder 17 having a width of 100 microns was obtained on the surface of the electrostrictive material on and around the exposed portion of the internal electrode, as shown in FIG.

After removing the adhesive tape on the back side, it was held at 705° C. for 10 minutes to be baked and fixed, thereby forming a glass cover gX.

Next, form a glass coating on the opposite side. After protecting the surface on which the coating has already been formed by covering it with adhesive tape, apply the number 16 in the figure.
Connect the temporary external electrode shown with the negative terminal of the DC power supply and apply a voltage in the same way as the first time.
t Deposit glass powder on the exposed part of the shoe and the ceramic around it. This is fired in the same manner as the first time to form a band-shaped glass coating. FIG. 5 is an external view of the laminate after forming the glass coating. Number 18 in the figure indicates a glass coating.

Next, external electrodes are similarly formed on the back surface of the laminate by coating and baking external electrode paste at several locations across the remaining internal electrode exposed portions and insulators. FIG. 6 is an external view of an electrostrictive material laminate in which a plurality of external electrodes are formed.

Number 21 in the figure is an external electrode. Thereafter, it is cut along the part indicated by the broken line in the figure, and the part indicated by number 2o in the figure is used as an element.

FIG. 7 shows an external view of an electrically connected element. Numbers 22 and 23 in FIG. 0 are negative sides, respectively.

Indicates the positive external connection terminal.

(Effects of the Invention) By the method of the present invention, it has become possible to stably mass-produce an integrated all-solid-state electrostrictive effect element that exceeds the performance of the conventional single-plate υ mating type in all aspects. . In other words, the driving voltage decreases from 200V to 100OV to 100V or less,
The response speed was improved from about 40 μsec to 10 μsec or less. In addition, the insulation effect of the glass coating using multilayer ceramic capacitor technology and electrophoresis method makes it possible to process a large number of elements at the same time, increasing productivity.
Reliability has been greatly improved.

[Brief explanation of the drawing]

FIGS. 1(a) and 1(b) are external views showing an element having a veneer structure using piezoelectric or electrostrictive effects and thin plates that are its constituent elements. In the figure, 1 is a thin plate of piezoelectric material or electrostrictive material, 2 is a baked electrode, 3 is an adhesive layer, and 4 and 5 are positive and negative external connection terminals, respectively. FIGS. 2 and 3 are external views showing the front and back sides of an electrostrictive material laminate with temporary external electrodes to which electrophoresis is applied. 11 in the figure is a portion of the electrostrictive material that does not generate strain;
12 is the electrostrictive material in the part where strain is generated, 13 and 14 are internal electrodes, 15 and 16 are temporary external electrodes, and FIGS. FIG. 2 is an external view showing a nine-electrostrictive material laminate with glass powder attached thereto. In the figure, 17 is the attached glass powder or glass coating, 18 is the attached glass powder or glass coating, and FIG. 6 is an external view showing the nine electrostrictive material laminate with external electrodes formed thereon. In the figure, 21 is an external electrode, and the seventh
The figure is an external view showing an electrostrictive element. 22.23 in the figure
are negative and positive, respectively.
Jin no 71-1 Figure<b) O 6 Figure 0

Claims (2)

[Claims] (1) A multilayer chip capacitor-type laminate in which electrostrictive materials and internal electrodes are alternately laminated, with all internal electrode layers exposed in addition to two opposing sides where internal electrode layers are exposed every other layer. forming a first external electrode on two side surfaces where the internal electrodes are exposed every other layer; and forming a first external electrode on one of the two side surfaces where all the internal electrode layers are exposed. An insulator is formed on every other internal electrode layer and its vicinity on one surface, and an insulator is formed on every other internal electrode layer and its vicinity, which is different from the internal electrode layer on which the insulator is formed, on the other surface. a step of forming at least one set of second external electrodes to be connected across the exposed internal electrodes at opposing positions on each of the two side surfaces on which the insulator is formed; A method for manufacturing an electrostrictive effect element, comprising a step of cutting between the second external electrodes, between the Jth external electrode and the second external electrode, and between a plurality of sets of second external electrodes. . (2) To form the insulator, the laminate and the counter electrode plate are placed in a suspension containing charged insulator powder, and electrophoresis is performed using the exposed internal electrode layer covering the insulator and the counter electrode plate as electrodes. 2. A method for manufacturing an electrostrictive effect element according to claim 1, wherein the electrostrictive element is coated with an insulating material by a method and then baked and fixed.