JP4083435B2 - Deposition frame for electrode formation of piezoelectric material - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an evaporation frame for forming an electrode of a piezoelectric element plate used when forming an excitation electrode on the piezoelectric element plate.
[0002]
[Prior art]
Conventionally, it is generally known to form a piezoelectric vibrator that excites piezoelectric vibration by cutting a piezoelectric material into a plate by cutting it at a predetermined angle and forming an electrode made of a metal thin film on the plate surface by vacuum evaporation or the like. It has been. Such a piezoelectric vibrator is widely used as a reference signal such as a frequency which is a clock signal in many fields of electronic circuits. In particular, crystal resonators that use quartz as the piezoelectric element plate are used in a wide range of fields and products because the crystal material is the best clock signal characteristic of piezoelectric materials, and in recent years crystal oscillators can be manufactured in large quantities at low cost. It has been broken.
[0003]
In the manufacturing process of the crystal unit, when forming the excitation electrode on the piezoelectric element plate, for example, in a vacuum atmosphere, the metal constituting the electrode such as aluminum, silver, or gold is heated to generate metal vapor (so-called vacuum deposition method). The electrode is formed by depositing a metal thin film on the piezoelectric element plate in a vacuum atmosphere. When forming an electrode by such vacuum vapor deposition, vapor deposition is performed by sandwiching a plurality of piezoelectric element plates between vapor deposition frames in order to increase productivity in a vacuum atmosphere.
[0004]
FIG. 3 is a perspective view showing an example of a deposition frame mainly used today, which is composed of an auxiliary frame, a mask plate, and a spacer plate, and corresponds to the outer shape of the piezoelectric element plate on which electrodes are to be formed. A holding hole is formed, and the piezoelectric element plate 4 is disposed in the holding hole. Further, mask holes corresponding to the shapes of the excitation electrodes to be formed on the both side plate surfaces of the piezoelectric element plate 4 are formed in the mask plates. Then, the piezoelectric element plate 4 is arranged in the holding hole of the spacer plate, the mask plate and the auxiliary frame are arranged on both sides thereof, and all of them are joined by screwing to constitute the vapor deposition frame.
[0005]
When sandwiching the piezoelectric element plate 4 in such a vapor deposition frame, it is necessary to apply a clamping force uniformly to each piezoelectric element plate 4 so that the mask plate is brought into close contact with the plate surface of the piezoelectric element plate 4. Therefore, when screwing the entire vapor deposition frame, a large number of screw joint portions are provided at relatively narrow intervals and tightened in the thickness direction (a form in which the plate surfaces are bonded together) to be integrated. In the actual manufacturing process, as the work amount of the daily vapor deposition process, the vapor deposition frame is all separated, the piezoelectric element plate is arranged on the spacer plate, and the mask plate and the auxiliary frame are screwed again, the spacer plate, mask plate, auxiliary The frame is integrated in a single flat plate shape, which is a work process that requires much labor. Further, the vapor deposition apparatus itself has a factor that requires a work time because the vapor deposition operation in one step is a batch process.
[0006]
[Problems to be solved by the invention]
Therefore, in order to improve the conventional working method described above, it was decided to try to improve mainly the vapor deposition process. One of them is a sputtering type vapor deposition method of a conventional vacuum vapor deposition method and another vapor deposition method. The concept of the vapor deposition method will be briefly described below.
[0007]
The vacuum deposition method uses a phenomenon in which an electrode metal material is scattered by heating an electrode metal material (for example, aluminum, silver, gold, etc.) to a deposition object (for example, a piezoelectric element plate such as a crystal material) in a vacuum atmosphere. The electrode metal material is attached to the deposition object.
[0008]
Therefore, generally speaking, the batch processing (refers to one process until the completion of the deposition process, putting the deposition object into the vapor deposition machine and performing the vapor deposition work) is the basic vapor deposition work. It will be an intermittent work that said to do. In addition, since vapor deposition itself requires a high vacuum atmosphere as a condition for heating and scattering the electrode metal material, it also requires time to reach the condition for the actual electrode metal material scattering time, One process of the vapor deposition operation takes time.
[0009]
On the other hand, the sputter deposition method is in the atmosphere of an inert gas such as argon gas or a mixed gas with oxygen, for example, as an electrode metal material. No atmosphere is needed. Further, in this gas atmosphere, the electrode metal material is struck by ions as an ion beam so that the electrode metal material scatters, and the scattered electrode metal material adheres to the deposition object in the same manner as the vacuum evaporation method.
[0010]
Therefore, compared to the vacuum deposition method, the time required to satisfy the deposition environment conditions can be shortened, and further, continuous deposition work can be realized instead of batch processing, improving the efficiency of the deposition work itself. It can be performed.
[0011]
However, in the sputtering deposition method, the electrode metal material is highly likely to be scattered in a small gap between the piezoelectric element plate and the mask plate, so the mask plate and the piezoelectric element plate are more closely adhered than ever before. It is necessary to use a frame.
[0012]
Thus, although the conventional vapor deposition process was able to be improved by improving a vapor deposition method, the subject of scattering prevention of electrode metal materials other than the vapor deposition surface remains by using the above-mentioned vapor deposition frame.
[0013]
[Means for Solving the Problems]
Accordingly, the present invention provides first and second spacer plates in which a plurality of piezoelectric element plates are accommodated and held, and mask holes corresponding to electrode shapes to be formed in units of the piezoelectric element plates accommodated in the spacer plates. It is composed of a mask plate and first and second auxiliary frames , the first mask plate is bonded to the spacer plate, and the first auxiliary frame is bonded to the outside of the plate surface of the first mask plate. The second mask plate and the second auxiliary frame have a structure in which the second mask plate and the second auxiliary frame are divided into a plurality of parts on the plane of the plate on the spacer plate. .
[0015]
In this case, when the mask plate and the auxiliary frame are arranged on both sides of the spacer plate with the spacer plate as the center, one mask plate and the auxiliary frame are previously bonded to each other by welding or bonding so as to have an integrated structure. Thus, the workability is improved, and the rigidity of the entire vapor deposition frame is increased by using the auxiliary frame, so that the mask plate can be prevented from being deformed and uniformly bonded. Moreover, since the adhesion between the mask plate and the piezoelectric element plate per sheet is increased by dividing the mask plate and the auxiliary frame, it is possible to prevent the electrode metal material from scattering to other than the vapor deposition surface.
[0016]
As described above, by joining the individual auxiliary frame, mask plate, and spacer plate by screwing, etc., the spacer plate, mask plate on one side, and auxiliary frame are joined to form a single flat plate. The work process of putting the piezoelectric element plate into the vapor deposition frame is improved. Also, by dividing the mask plate and the auxiliary frame, the electrode material vapor deposition for electrode formation has improved the possibility that the electrode metal material adheres to other than the vapor deposition surface from a slight gap between the mask plate and the piezoelectric element plate. It is a frame.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. In each figure, the same numerals indicate the same objects.
FIG. 1 shows a vapor deposition frame 8 which is a basic configuration of the present invention. A spacer plate 3 made of a thin metal plate (for example, stainless steel) is provided with a holding hole 10 corresponding to the outer shape of the piezoelectric element plate 1 on which an electrode is to be formed by etching or the like. Reference numerals 4 and 5 denote first and second mask plates which are attached to both side surfaces of the spacer plate 3. The first and second mask plates 4 and 5 are also made of a thin metal plate similar to the spacer plate 3, and corresponding to the holding holes 10 formed in the spacer plate 3, the electrode shapes to be formed on the piezoelectric element plate 1, respectively. A hole 11 (mask hole 11 serving as an electrode pattern) is formed in a mask plate corresponding to the above. For example, a crystal resonator or the like (drawn as a round plate-like piezoelectric element plate 1 in the drawing) is narrowly provided in the vapor deposition frame 8 assembled in this way, and an actual vapor deposition operation is performed. Although not shown, the spacer plate 3, the first and second mask plates 4, 5 are held by screws.
[0018]
As shown in FIG. 2, the present invention is characterized in that the mask plate (51, 52, 53, 54) attached to at least one side of the spacer plate 3 of the vapor deposition frame 8 and the auxiliary frame (71, 72, 73, 74) is divided into a plurality of planes on the plane of the plate, so that the gap between the spacer plate 3 and the mask plate is further reduced by reducing the plate surface area sandwiching the piezoelectric element plate 1. It is possible to eliminate the scattering of the electrode metal material at the time of vapor deposition other than the necessary electrode part. Moreover, even if the piezoelectric element plate 1 is displaced from the spacer plate 3 by a part of the vapor deposition frame 8 during the vapor deposition operation, the synergistic effect to other parts is cut off due to the divided structure. You can also
[0019]
Here, the divided structure improves the effect of the vapor deposition frame 8 of the present invention as long as the mask plate attached to at least one side of the spacer plate 3 and the auxiliary frame are divided into a plurality of planes on the plate surface. However, the mask plates (4, 5) and the auxiliary frames (6, 7) attached to both of the spacer plates 3 as viewed from the center may be divided. In FIG. 2, it is expressed as four divisions, but there is no restriction on the number of divisions.
Although not shown in FIG. 2, the spacer plate 3, the first and second mask plates 4, 5, and the first and second auxiliary frames 6 and 7 are held by screws.
[0020]
The spacer plate 3, the max plate, and the auxiliary frame described above are made by etching a stainless steel thin metal plate, but the spacer plate 3, the max plate, and the auxiliary frame are made of stainless steel and are made of SUS304. Even if a material is used, there is no influence even if a magnetic material of SUS430 is used.
[0021]
In the present embodiment, an example in which the crystal resonator using the piezoelectric element plate 1 having a round plate shape is described is described. However, when an electrode is formed on the strip-shaped piezoelectric element plate 1. Is also applicable. Needless to say, the same effect can be obtained even in the form of a vibrator made of a piezoelectric material other than the quartz vibrator.
[0022]
【The invention's effect】
As described above, from the joining method in which the individual auxiliary frame, the mask plate, and the spacer plate are integrated by screwing, the spacer plate and the vapor deposition frame in the form of joining one of the mask plate and the auxiliary frame are used. This improves the work process of putting the piezoelectric element plate into the vapor deposition frame, and the surface of the piezoelectric element plate to which the electrode metal material should originally adhere as an electrode from a slight gap between the mask plate and the piezoelectric element plate However, as an improvement to these, a vapor deposition frame for forming an electrode of a piezoelectric material having more adhesiveness can be realized by dividing the mask plate of the vapor deposition frame and the auxiliary frame.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a basic form of the present invention.
FIG. 2 is a perspective view illustrating features of the present invention.
FIG. 3 is a perspective view showing a conventional auxiliary frame.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Piezoelectric element board 2 Electrode 3 Spacer board 4 1st mask board 5 2nd mask board 6 1st auxiliary frame 7 2nd auxiliary frame 8 Evaporation frame

Claims (1)

A first and a second mask plate in which a plurality of piezoelectric element plates are accommodated and held, and mask holes corresponding to electrode shapes to be formed in units of the piezoelectric element plates accommodated in the spacer plate are arranged; 1 and a second auxiliary frame, the first mask plate is joined to the spacer plate, and the first auxiliary frame is joined to the outside of the plate surface of the first mask plate, mask plate and the second auxiliary frame for forming an electrode deposition frame of the piezoelectric material, which is a structure which is arranged to be divided into a plurality at the plate surface plane on the spacer plate.

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