JP5052822B2 - Method for manufacturing piezoelectric vibrator container member - Google Patents

Description

The present invention improves the fact that due to the difference in coefficient of thermal expansion between the container and the lid, thermal stress is applied during welding and sealing, distortion remains, and the bonding strength of the package cannot be maintained, and the package is further reduced in height. it relates to a package of production how.

  Ceramic, glass, metal, resin, and the like are used for the package of the small SMD vibrator, and ceramic, metal, and glass with high humidity resistance and airtightness are used for those that require accuracy. Resin packages are used for general consumer products that have relatively high stability due to their hygroscopicity and airtightness.

  As for the lid, metal, ceramic, glass, etc. with good airtightness and moisture resistance are used in the same way as the package. Sealing methods include seam welding of metal lids, gold-tin fusion, glass fusion of ceramic caps, metal Welding of the base and metal cap is used, and electron beams and lasers are also being used and studied.

  Recently, the use of mobile terminals continues to expand, such as IC tags, TV modules, GPS receivers, hard disk (HDD) modules, and the applications continue to increase. In order to satisfy the functions, GPS modules, HDD modules, tuner modules, etc. are installed in terminals. There is a tendency to increase the number of functional parts. On the other hand, since the size of the terminal device itself is limited, there is an increasing demand for reducing the size and height of parts while maintaining accuracy, airtightness, and moisture resistance.

  Strict demands are also made on the unit price of products, and the issue is how to increase the productivity by reducing the investment in material costs. However, in order to achieve ultra-compact and low profile while ensuring accuracy and reliability, it is necessary to reduce the thickness of the bottom surface and the lid. The mainstream of ceramic material packages is that the lid is made of metal, and due to the difference in the thermal expansion coefficient between the ceramic container and the lid, thermal stress is applied during welding and sealing, strain remains, and the package strength is maintained. Therefore, materials and sealing methods are also limited. At present, a small hermetic sealing method with an outer dimension of 2.5 mm × 2.0 mm or less is a gold tin lid heat fusion method or an Ag wax cladding. Welding with lid electron beams is the mainstream.

In recent years, there has also been proposed a method in which vibrators are collectively formed from a quartz wafer by photolithography and collectively sealed by anodic bonding in the wafer state. In addition, a method has been proposed in which glass is used for a base (package) and strip-shaped vibrators are individually mounted and adjusted and then collectively sealed in a wafer state. On the other hand, since the size of the terminal device itself is limited, there is an increasing demand for reducing the size and height of parts while maintaining accuracy, airtightness, and moisture resistance.
JP 2006-129290 A JP, 2000-295059, A In addition to the prior art documents specified by the prior art document information described above, the applicant has not found prior art documents related to the present invention by the time of filing of the present application. .

  A general piezoelectric vibrator has a configuration in which a vibrating piece in which electrodes for excitation are formed on both surfaces of a flat plate of a piezoelectric material is housed as a piezoelectric vibrating element plate in a container shape having an airtight seal. Therefore, in order to achieve both the sealing shape, airtightness, and moisture resistance of the piezoelectric vibrator container, it is common to use inorganic materials such as glass, ceramic, and metal for the package. Further, it is necessary to make the entire container smaller and thinner at the same time by reducing the thickness of the lid.

  However, the mainstream of ceramic material packages is that the lid is made of metal, and due to the difference in the thermal expansion coefficient of the ceramic container and lid, thermal stress is applied during welding and sealing, and strain remains, so that the container remains Since the package strength cannot be maintained by reducing the thickness of the component, the current situation is that it is difficult to further reduce the height of the current package.

  Therefore, in order to solve the above-described problems, the present invention includes a step of applying and curing a polyimide resin on a glass plate, a step of forming a via in the resin, an aluminum film on the resin, and performing exposure and development. After the pattern is formed, the resist is peeled off and the glass is peeled off. The resin formed so far is reversed and bonded onto the glass plate again. The aluminum film is formed on the back surface of the resin, and the via is formed by exposure and development. And a method of manufacturing a piezoelectric vibrator container member obtained by a step of forming an electrode that is electrically connected to the glass plate and a step of peeling from the glass plate.

  In short, in order to achieve both of the sealing form, airtightness, and moisture resistance of the piezoelectric vibrator container, the present invention generally uses polyimide, which used an inorganic material such as glass, ceramic, or metal as a packaging material. The container body is formed efficiently using resin material. As a result, the bottom and lid thickness can be made thinner than conventional products, and the entire container can be made smaller. At the same time, it is made thinner.

  According to the present invention, a liquid crystal polyimide is used for a substrate, a thin film is formed by spin coating, a through hole is formed by lithography, and a pattern is formed by a metal film, thereby forming an ultra-thin crystal resonator base. The conventional problem can be solved by forming an extremely thin container. Further, the glass wafer can be sealed collectively by anodically bonding the glass wafer to the container described above and sealing. As a result, since polyimide resin is used for the substrate, it has elasticity and can secure strength such as bending even if it is thinned. Improve, shorten manufacturing time and realize cost reduction.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. As described above, the present inventor has found one method of manufacturing a container containing a piezoelectric vibrator in which excitation electrodes are formed on the front and back of a piezoelectric element plate using polyimide resin. Is. FIG. 1 is a flowchart illustrating a process of obtaining the container of the present invention, FIG. 2 is a conceptual diagram showing a partial progress of FIG. 1, and FIG. 3 is a schematic diagram of a vibrator using the container of the present invention. FIG.

  The flow chart shown in FIG. 1 shows the flow of the present invention, the content of which is based on the description of claim 1, a step of applying a polyimide resin on a glass plate and curing, and a step of forming a via in the resin. A process of forming an aluminum film on the resin, peeling the resist after patterning by exposure and development, and peeling the glass; inverting the resin formed so far and pasting it on the glass plate again; and A method of manufacturing a piezoelectric vibrator container member obtained by a process of forming an aluminum film on the substrate and forming an electrode that is electrically connected to the via by exposure and development, and a process of peeling from the glass plate.

  In short, (1) SOG (abbreviation of Spin On Glass, a substance mainly used as an insulating film in the semiconductor field) including polyimide resin is used for the base as a container material, and (2 ) Thin film is formed on glass or Si substrate by spin coating etc. and cured to form resin sheet, (3) Through hole is formed by photolithography, (4) Crystal oscillator mounting pattern, seal A surface pattern is formed by photolithography using aluminum or the like, and (5) a resin sheet from which a resin material is peeled from glass is cured later to form an ultra-thin container.

  Furthermore, (6) the container described above is inverted and temporarily attached to glass or the like, and a mounting pattern is formed on the back surface of the resin sheet, and the front and back of the container are realized by ensuring conduction of the through holes. (7) A crystal resonator is mounted on the completed container, and after adjusting the frequency of the crystal resonator, a cover made of sheet-like glass is placed on the aluminum seal surface and sealed together by anodic bonding or the like.

  In short, by using liquid polyimide for the substrate, a thin film is formed by spin coating, and through holes and patterns are formed by lithography, an ultrathin quartz crystal base can be produced. By anodic bonding, it is possible to collectively seal and improve productivity.

  FIG. 2 shows a partial form of the flow diagram shown in FIG. The process flows from the top to the bottom of the page. In FIG. 2, polyimide resin is applied to a glass plate and cured to form through holes (vias) for ensuring conduction between the front and back surfaces of the resin, and an aluminum film is formed on the surface of the resin to accommodate the piezoelectric vibrator. The partial concept of this invention which forms and peels a polyimide resin from glass is shown. Furthermore, in the present invention, the piezoelectric vibrator is formed by a series of processes in which the above resin is reversed and pasted on the glass again, and patterning is performed on the back surface of the resin sheet to form an electrode for ensuring connection with the outside. A container to be stored is formed.

  FIG. 3 shows a conceptual diagram of a sealed container structure containing a piezoelectric vibrator and further using a sheet-like glass as a lid. As can be seen from the flow chart of the present invention shown in FIG. By forming the container body at one time and housing the piezoelectric vibrators in a plurality of containers and using sheet-like glass as a lid, a plurality of piezoelectric vibrators having a sealed structure can be obtained simultaneously.

  In the present invention, photosensitive polyimide resin is used as the polyimide resin (for example, UV curing), but it is used as an insulating film in the semiconductor field as SOG (abbreviation of Spin On Glass) instead of polyimide resin. It can also be configured using materials.

It is a flowchart which shows the flow of the manufacturing process of this invention. It is a conceptual diagram which shows the state obtained by a part of process of this invention. It is the conceptual diagram which showed the state which mounts a piezoelectric vibrator in the container obtained by this invention.

Claims (1)

  A step of applying and curing a polyimide resin on a glass plate, a step of forming a via in the resin, a step of forming an aluminum film on the resin, peeling the resist after pattern formation by exposure and development, and peeling the glass Reversing the resin formed so far and pasting it on the glass plate again, forming an aluminum film on the back surface of the resin and forming an electrode that is electrically connected to the via by exposure and development, and the glass plate A method for manufacturing a piezoelectric vibrator container member obtained by a step of peeling from a piezoelectric member.

Images