JPH01188492A - Vapor phase synthesis device - Google Patents

Abstract

PURPOSE:To directly grow a crystal body suitable for cutting out a stock for a condenser lens for large output, etc., by disposing a raw material supply nozzle in a specific form and synthesizing a circular columnar crystal body in a vapor phase. CONSTITUTION:The circular columnar crystal body, for example, ZnSe crystal body, is prepared in the following manner: A hollow cylindrical base body which is closed at one end and has a round bar at the center is supported at the center of a reaction chamber by a revolving shaft. Nozzles for supplying gaseous H2Se and a Zn vapor-contg. carrier gas are oppositely disposed to the open end of this base body and if necessary, a flat plate base body is placed around this base body and is heated by a heater provided on the outside of the reaction chamber to the crystal growth temp. Since the inside of the hollow cylindrical base body is blown directly with the gaseous raw materials from the supply nozzles, the crystal growth speed is extremely higher than the crystal growth speed of the outside. The vapor growth is ended in the stage when the crystals deposit successively in this base body and the inside of the base body is completely filled therewith. The deposition of the crystals is uniformized by rotating the base body.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a vapor phase synthesis apparatus for depositing a cylindrical crystal body on a substrate, which is suitable for cutting out a material such as a condenser lens having a through hole in the center. .

(Prior Art) In recent years, the uses of laser light have been rapidly expanding, and among these, there is a demand for high output laser processing machines used for welding, cutting, heat treatment, etc. For example, when a workpiece with a large heat capacity is to be processed, such as when used in a steel rolling line, a particularly high-output laser processing machine is required. When using a laser with a large output of 5 kW or more, an unstable resonator is generally used.

The energy profile of laser light using this unstable resonator is a ring mode near the laser oscillator. However, at a position sufficiently far away from the laser oscillator, the energy profile becomes a mode concentrated in the center due to the light diffraction effect and the thermal lens effect of the laser light extraction window. For this reason, a large thermal load was applied to the center of the condenser lens, and the condenser lens was often destroyed. In order to solve this problem, a condensing lens having a through hole in the center is used. ” Examples of materials for such condensing lenses include Zn5.
e crystals are used. The condensing lens extracts a plate-shaped crystal from a crystal deposited on a substrate using the vapor phase synthesis method.
It is hollowed out into a circular shape, the outer periphery and both sides are ground, then lapped and polished, and then finished into a predetermined shape for use. There are two types of equipment used for vapor phase synthesis: vertical and horizontal.

FIG. 2 is a conceptual diagram of a conventional vertical vapor phase synthesis apparatus. A substrate is placed inside the reaction chamber and heated from the outside to a crystal growth temperature using a heater. Zn vapor carried by a carrier gas such as an inert gas and H, Se gas are separately supplied from two upward nozzles with openings near the substrate for vapor phase synthesis to form Zn5e crystals on the substrate. Deposits.Figure 3 shows Z
FIG. 2 is a cross-sectional view of a substrate on which n5e crystals are deposited. Figure 3 (A
) are four substrates, and FIG.
The area on which crystals are deposited is increased by making it into a rectangular cylindrical shape. These plate-shaped Zn5e crystals are
Remove it from the board and make it into a single flat plate. Next, a circular material is cut out from this flat plate as shown in FIG. 4, a through hole is made as shown in FIG. 5, and the material is processed and polished into a predetermined shape to form an optical component.

(Problem to be Solved by the Invention) As described above, when making a condensing lens by growing a flat crystal using a conventional vapor phase synthesis apparatus, then cutting out a circular material and making a through hole, it is necessary to The production of unusable parts between the circles and through-holes also limited the yield of the input raw materials.

Therefore, the present invention solves the above problems by directly growing a cylindrical crystal body with a through hole in the center using a vapor phase synthesis process, which is suitable for cutting out materials for high-output condensing lenses, etc. The aim is to provide a device that allows

(Means for Solving the Problems) The present invention provides an apparatus for vapor phase synthesis of a cylindrical crystal body suitable for collecting a circular material having a through hole in the center. A hollow cylindrical base on which a rod-shaped base is arranged is used, and the inner diameter of the cylindrical part of the base corresponds to the diameter of the circular material, and the outer diameter of the round bar part corresponds to the outer diameter of the through hole of the circular material. This is a vapor phase synthesis apparatus characterized in that a raw material gas supply nozzle is arranged so as to face the open end of the gas phase synthesis apparatus.

Note that in order to uniformly deposit crystals on the substrate, it is preferable to rotate the hollow cylindrical substrate. Furthermore, the raw material gas blown into the inside of the hollow cylindrical base eventually overflows and exits the exhaust system through the outside of the base, and crystals are deposited on the outside of the base as well. Therefore, a flat substrate may be placed around the substrate in order to increase the recovery rate of crystals.

In addition, if the final shape to be collected is a circular material with a through hole in the center, such as a high-power condensing lens, the inner diameter of the hollow cylindrical base should be slightly larger than the diameter of the material, and the through hole should be If the outer diameter of the round rod-shaped base is designed to be slightly smaller than the diameter, by slicing the cylindrical crystal that has grown inside the base and slightly processing and polishing the circumferential side, the outer diameter and through hole of the predetermined dimensions can be obtained. Circular blanks with a diameter can be produced.

Note that the hollow cylindrical base having a round rod in the center can be easily formed from carbon or the like.

(Function) FIG. 1 is a conceptual diagram of a vapor phase synthesis apparatus that is a specific example of the present invention. The following description will be made using the creation of a Zn5e crystal as an example.

A hollow cylindrical substrate with one end closed and a round bar in the center is supported in the center of the reaction chamber by a rotating shaft, and a carrier gas supply nozzle containing H, Se gas and Zn vapor is opposed to the open end of the substrate. If necessary, a flat substrate is placed around the substrate and heated to a crystal growth temperature by a heater provided outside the reaction chamber.

Since the raw material gas is directly blown into the inside of the hollow cylindrical substrate from the supply nozzle, the crystal growth rate is extremely high compared to the outside. The vapor phase synthesis is terminated at the stage when crystals are sequentially deposited and completely filled inside the substrate. This crystal deposition can be made uniform by rotating the substrate. Note that crystals also grow on the outside of the cylindrical substrate and on the surface of the flat substrate as shown in the figure.

By slicing the cylindrical crystal body having a through hole and removing it from the hollow cylindrical substrate to an appropriate thickness, it can be used as it is as a circular material for a condenser lens having a through hole.

In this way, the vapor phase synthesis apparatus of the present invention can directly create a cylindrical crystal body having a through hole of a predetermined diameter and a predetermined outer diameter, so the yield of the crystal body is dramatically improved, and subsequent Machining for creating optical parts etc. could be greatly simplified.

Although a vertical type vapor phase synthesis apparatus is shown in FIG. 1, a horizontal type can also be used. Also, Zn5e
Other crystals can be similarly synthesized in a vapor phase.

(Example) A Zn5e crystal was produced using the vapor phase synthesis apparatus shown in FIG. The hollow cylindrical base has an inner diameter of 80mm and a depth of 100I.
The inner round rod is a carbon base with an outer diameter of 7 mm and a length of 100 m. The flow rate of H, Se gas is 0
．． 5ON 1/1llin.

The flow rate of carrier gas containing Zn vapor is 0.25N1/ll.
1 inch, and the combined pressure was 40 Torr. Also,
The substrate was heated to 750° C. by a surrounding heater, and the gas phase synthesis was continued for 400 hours at a rotation speed of 3 rpm. Thereafter, the crystal body was removed from the hollow cylindrical base, and a through hole with a diameter of 1 m was formed in the center. Height approx. 10
A cylindrical crystal body weighing about 2,600 g was obtained.

(Effects of the Invention) By adopting the above configuration, the present invention makes it possible to efficiently produce a uniform cylindrical crystal body having a through hole of a predetermined diameter and a predetermined outer diameter, and the obtained crystal body By slicing, it is possible to provide a circular material as is, dramatically improving the yield of crystals, and greatly simplifying the machining required to create a circular material with through holes. This greatly contributes to shortening manufacturing time.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram of a vapor phase synthesis apparatus which is a specific example of the present invention, Fig. 2 is a conceptual diagram of a conventional vapor phase synthesis apparatus, and Fig. 3 (A).
and (B) are cross-sectional views of the base of the conventional device, Figure 4 is a diagram for explaining the process of hollowing out a disk-shaped material from a flat crystal, and Figure 5 is an example of a condensing lens for high-power lasers. , in which (A) is a front view and (B) is a plan view. Figure 1 Kass ↑ An falling air 21 (A) Figure 3 (B) Figure 4 (A)

Claims (1)

[Claims] In an apparatus for vapor phase synthesis of a cylindrical crystal body suitable for collecting a circular material having a through hole in the center, a hollow cylindrical substrate with one end closed and a round bar-shaped substrate placed in the center is used. The base body has the inner diameter of the cylindrical part equal to the diameter of the circular material, and
A vapor phase synthesis apparatus characterized in that the outer diameter of the round bar portion corresponds to the outer diameter of the through hole of the circular material, and a raw material gas supply nozzle is arranged so as to face the open end of the base.