JP4938368B2 - Thin-film quartz plate manufacturing method and its transport tray - Google Patents

Description

  The present invention relates to a method for manufacturing a thin film crystal plate manufactured by an epitaxial method and a transport tray thereof.

  Crystal resonators, which are electronic components indispensable for cellular phones and digital home appliances, are widely used. Quartz resonators are used in various fields as accurate signal sources and timing devices. In order to manufacture a quartz crystal plate for a quartz resonator, a quartz plate made from artificial quartz to a wafer is used. However, there is a drawback that it takes a lot of time and steps to make a quartz crystal plate into a wafer by increasing the frequency.

  However, it takes a lot of labor and man-hours to cut, polish and polish the crystal piece. Therefore, a method of epitaxially growing quartz on a single crystal substrate to form a thin film quartz plate has been proposed. According to Japanese Patent No. 3592218 “Method for Producing Crystal Thin Film”, an alkyd is vaporized using silicon as a source under atmospheric pressure, a buffer layer is provided on a single crystal substrate, and further epitaxially grown on the buffer layer to produce a crystal thin film. Is forming. Therefore, a high-quality thin film quartz plate that does not require conventional polishing can be obtained.

  However, even if a thin film crystal plate is formed on a single crystal substrate, for example, a sapphire substrate, it is very difficult to process because it is thin to process into a crystal plate of the size to be used. When miniaturized, the variation in outer shape affects the characteristics and is related to the variation in quality. Therefore, there has been a demand for a method by which a quartz plate having a size to be finally used can be easily manufactured. In addition, if the crystal plate is transported in a thin film and is scattered, chipping may occur in the peripheral outline, and transport is difficult. Therefore, safe transport of the thin film crystal plate has been demanded.

Japanese Patent No. 3592218

  In addition to the prior art documents specified by the prior art document information described above, the applicant has not found any prior art documents related to the present invention by the time of filing of the present application.

  The problem to be solved by the present invention is that there is a need for a transportation means that can be easily processed in an accurate size to the size of the final use of the thin film crystal plate, and that can carry the thin film crystal plate without breaking. .

  Patent Document 1 describes a method of making a thin film quartz plate. FIG. 3 is a cross-sectional view showing a diagram for manufacturing a thin film crystal plate. For example, a crystal film is formed on a single crystal plate 10 such as sapphire or crystal by vapor phase growth by the method of Patent Document 1 or the like. First, the buffer layer 11 is formed on the single crystal plate 10. Further, a quartz thin film 12 is formed. The buffer layer 11 is in an intermediate state between the amorphous layer and the single crystal, and the crystal thin film 12 can be peeled off from the single crystal plate 10 by creating a temperature difference. For example, in the case of a thickness thin film vibrator, the frequency of the quartz thin film is determined by the thickness. Therefore, a high frequency can be oscillated when the thickness is thin, and a low frequency can be oscillated as the thickness increases.

The present invention relates to a method of manufacturing a thin film crystal plate manufactured using a crystal epitaxial thin film , wherein the bottom surface of the cell in which a plurality of cells having a concave cross section are formed has an area smaller than the opening area of the cell. A single crystal substrate is mounted and fixed so that a gap is formed between the single crystal substrate and the peripheral wall surface in the cell, and the alkoxide is vaporized using silicon as a source under atmospheric pressure to react on the single crystal substrate. Forming a thin film crystal plate, wherein a plurality of recesses are formed, and a single crystal substrate is mounted and fixed to the bottom of the recesses. A thin film crystal plate is formed on the single crystal substrate, and the thin film crystal plate is transported while being attached to the single crystal substrate.

  According to the present invention, a thin film crystal plate can be obtained without machining to make a thin piece of a size to be finally used. In addition, there is no damage that occurs when transporting the thin film quartz plate, and it is now possible to transport it with peace of mind.

Hereinafter, embodiments will be described with reference to the drawings.
FIG. 1 is an enlarged sectional view of one cell showing an embodiment of the present invention. A single crystal substrate that forms the frame 1 and the crystal flakes is placed on the bottom of the frame in the desired flake size. There are steps around the single crystal substrate. In the thin film crystal plate, a silicon source flows in the upper part of the frame or in the lateral direction, and reacts on the single crystal substrate to form a crystal thin film. The quartz crystal piece grows in accordance with the size of the single crystal substrate, and the crystal thin film does not grow on the edge of the single crystal substrate that grows in the thickness direction, so that a thin film quartz plate having the same size as the single crystal substrate is formed. Thereafter, unnecessary crystal flakes attached to the frame and the periphery of the single crystal substrate are removed.

And when transporting as it is or when transporting to the next process, it can be transported while being attached to the single crystal substrate. Therefore, it is not necessary to put in the tray for transporting the flakes, and there is no possibility of chipping or chipping in the flakes, so that the flakes can be transported with confidence.
When used as a thin piece, a temperature difference is generated, and it can be peeled off from a buffer layer directly attached to a single crystal substrate and used as a thin film crystal plate.

  FIG. 2 is an overall perspective view of the tray. A plurality of cells 4 are formed in the tray 1. The material of the tray 1 is a monolithic structure made of sapphire in which sapphire is cut out in this embodiment. Alternatively, it may be a monocrystalline silicon monolithic structure. The number of cells is prepared as necessary. The tray may be made of other materials such as quartz glass, soda glass, fine ceramic, etc. of an inorganic substrate, but at least the portion protruding to the bottom of each cell is sapphire, which is a single crystal substrate, or single crystal silicon. is necessary.

  Although not shown, a single crystal substrate having an area slightly smaller than the opening area of the cell is provided on the bottom surface of each cell. In the periphery of the single crystal substrate, a step is formed by the thickness of the single crystal substrate from the bottom of the cell, so that a gap is formed from the peripheral wall surface of the cell. Since the outer dimension of the thin film crystal plate substantially matches the dimension of the single crystal substrate in the gap, the outer dimension is determined by the single crystal substrate. The excess thin film crystal plate or the material remaining in the upper surface of the tray or in the gap between the cell and the single crystal substrate is removed before or after the thin film crystal plate is removed.

  According to the present invention, it has become possible to produce a thin-film quartz plate having a final outer dimension without any outer shape processing. Further, since the tray according to the present invention can be transported while being attached to the single crystal substrate, it can be transported safely without breakage.

  INDUSTRIAL APPLICABILITY The present invention can produce a high-frequency and miniaturized crystal plate, and can provide a miniaturized crystal resonator and a crystal oscillator for a crystal oscillator.

FIG. 1 is an enlarged cross-sectional view of one cell of the transport and example of the present invention. FIG. 2 is an external perspective view of the transfer tray. FIG. 3 is a cross-sectional view when a thin film crystal plate is formed on a single crystal substrate.

Explanation of symbols

1 tray 2 single crystal substrate 3 crystal thin film 4 cell

Claims (4)

In a method for manufacturing a thin film crystal plate manufactured using a crystal epitaxial thin film,
A single crystal substrate having an area smaller than the opening area of the cell is disposed between the single crystal substrate and a peripheral wall surface in the cell on the bottom surface of the tray in which a plurality of cells having a concave section are formed. It is placed and fixed so that there is a gap in the
Method of manufacturing a thin film quartz plate and forming a thin film crystal plate by the Ri該 single crystal substrate in vapor phase crystal growth method of silicon as a source at atmospheric pressure. A plurality of recesses are formed, a single crystal substrate is placed and fixed on the bottom of the recesses, a thin film crystal plate is formed on the single crystal substrate, and the thin crystal crystal plate is attached to the single crystal substrate and transported A thin film quartz plate carrying tray characterized by the above. 3. The thin film crystal plate carrying tray according to claim 2, wherein the single crystal substrate is made of sapphire. 3. The transfer tray according to claim 2, wherein the transfer tray has an integrated structure of sapphire.

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