JPS62230966A - Device for growing crystal - Google Patents

Abstract

PURPOSE:To make disturbance in stream regulation of an ion beam small and to strictly control film thickness by providing a partition plate between two injection means adjacent to each other for plural substances to be evaporated. CONSTITUTION:A partition plate 29 is provided between two injection means adjacent to each other for substances to be evaporated in a chamber 16 for growing crystal. The strength of the cluster ion beams projected from both a crucible 25 incorporated with metal A and a crucible 26 incorporated with metal B are regulated and the clusters of metal A, B are ionized by an independent acceleration electrode. After opening a shutter 32 and forming a thin film of metal A, a base plate 18 is transferred to form a laminated film of metal A B A.... By this method for growing crystal, since the partition plate 29 is present, the mixing of two ion beams is not caused and the boundary of the laminated layer of metal A, B is made clear and an excellent functional element is obtained and the soiling of an ion gun can be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a crystal growth apparatus for forming various functional elements by growing crystals, particularly thin films having a laminated structure or a superlattice structure, on a substrate; In particular, the present invention relates to a crystal growth apparatus capable of obtaining a functional element made of a plurality of crystals whose structure is accurately controlled.

[Conventional technology]

Conventionally, there are various types of crystal growth apparatuses, but the cluster ion beam generating means that performs crystal growth using a device equipped with a cluster ion beam generating means has a large adhesion force, can control the orientation, and can It has the advantage of lower temperature.

A conventional crystal growth apparatus having a plurality of cluster ion beam generating means will be described below with reference to FIG.

The components shown in Figure 2 are a crystal I & long chamber 1, a substrate 2, a grown crystal 3, a cluster ion beam 4°5, shanks 6 and 7 for controlling the cluster ion beam, and an accelerating electrode 8.
, 9, filament for ionization 10 , +1. Crucibles 12 and 13, and cluster ion guns 14 and 15. In this device, the potential of the accelerating electrode can be set to any potential difference up to about +IQKV or -IQKV with respect to the substrate.

Crystal growth depends on the degree of vacuum in the crystal growth chamber 1, the temperature of the substrate 2,
This is carried out by setting the temperature of the crucible 12.13, the potential of the accelerating electrode 8.9 (to the plate), and the ionization rate by the ionization filament 10°11 to predetermined values.

In this (7) apparatus, in order to cause the material in the crucible to grow crystals alternately on the substrate, the structure of the formed film 71 is controlled by alternately opening and closing the shutters 6 and 7 and changing this period.

[Problem that the invention seeks to solve]

In this method, when the shutter is opened and closed, the flow of the ion beam from each ion gun is greatly disturbed, and the interface of the laminated film is not clear, and furthermore, when the distance between the ion guns is relatively close, when the shutter is closed, There was a problem in that other ion guns were contaminated by the evaporated substances that bounced off the shutter.

The present invention has been made in view of the above-mentioned problems, and its purpose is to be able to control the flow of a plurality of ion beams without disturbing the flow of the ion beams, to obtain an excellent functional element, and to improve the performance of an ion gun. An object of the present invention is to provide a crystal growth apparatus that does not cause dirt.

[Means for solving problems]

The above-mentioned object of the present invention is to provide a crystal growth apparatus having a plurality of evaporated material ejecting means in a crystal growth chamber and a holder for a substrate to which the evaporated material is attached, the apparatus comprising: This is achieved by a crystal growth apparatus that is provided with a partition plate that passes through it.

The outline of the present invention will be explained with reference to FIG. 1, taking as an example the production of a metal laminated film using an apparatus having a plurality of cluster ion beam generating means.

The components shown in FIG. 1 are a crystal growth chamber 18, a disk-shaped rotating substrate holder 17, and a metal thin film grown on a substrate attached to the semicircular portion of the substrate holder 18. Thin film 18' after half a rotation due to substrate rotation, a spot 25 containing metal A to be evaporated, a spot 26 containing metal B, and cluster ion beams 19 of metals A and B, respectively.
, 20, acceleration electrodes 21, 22, ionization filaments 23, 24, and a partition plate 29 between the two cluster ion guns. This partition plate 29 extends from between the two cluster ion guns to just in front of the substrate.

Using this apparatus, for example, an alternating layered film of two types of metals A and B is produced, for example, in the following manner.

It is assumed that the film structure is deposited in the order of A→B -A -B----→A, and the pot 25 contains metal A, and the crucible 26 contains gold [B]. The substrate holder is rotated by a pulse motor and rotates half a rotation with one pulse, and this pulse is received by a microcomputer that receives a signal from a film thickness monitor such as a crystal oscillator, and this microcomputer gives instructions. First, enter various film thicknesses into the microcomputer. First, reduce the pressure inside the crystal growth chamber, set the vacuum level and substrate temperature, and adjust the intensity of the cluster ion beam from the crucible 25 and 26 to determine the film thickness of the crystal oscillator, etc. desired one on the monitor
21 to become a song! I fall. The accelerating electrodes of the cluster ion gun are set independently for gold iA and H, and the clusters of gold iA and B are ionized by the ionization filament. The substrate shutter 32 is opened by a microcomputer, and a thin film of metal A is first produced. When the initially set film thickness is reached, the substrate holder 17 is rotated half a turn according to instructions from the microcomputer so that the substrate 18 is at the position 18'. By repeating this process, a laminated film of A-B-A→B----→A is obtained.

When crystal growth is performed using the method described above, there is no mixing of the two ion beams due to the partition plate 29, and the metal A
The laminated interface between and B becomes clear. In addition, if the vapor deposition conditions of metals A and H, especially the potential difference applied to the accelerating electrodes, are different, if there is no partition plate, the electric places will interact with each other and uniform acceleration conditions will not be obtained. This also has the great advantage of providing independent and uniform acceleration conditions.

Although the above embodiment shows an example of obtaining a metal laminated film using the crystal growth apparatus of the present invention, the present invention is not limited to this and is also effective for materials other than metals. In the vapor deposition method, the vapor-deposited substance reaches the substrate as ions with a charge of 10, but there are positive and negative 'r[
The partition plate is also effective in stabilizing the accelerating voltage for each ion gun and preventing discharge when evaporating substances with r-loads alternately or simultaneously. (If vapor deposition is performed at the same time, reduce the height of the partition plate to match the size of the substrate.) Furthermore, if cluster ion base and electron beam heating vapor deposition are used together, the electrons from the electron gun will flow directly to the cluster ion gun. However, this problem can be prevented by installing a partition plate.

The crystal growth apparatus of the present invention is applicable not only to cluster ion beam evaporation, but also to vacuum evaporation using multiple evaporation sources, including ionization evaporation, and is also effective when ions are implanted during vacuum evaporation. be.

As explained above, since the apparatus of the present invention has a partition plate, when a plurality of evaporation substances are deposited on a substrate alternately or simultaneously, each evaporation condition is maintained independently and mutual influence is eliminated. effective. This makes it possible to clarify the interface of laminated films, improve the accuracy of monitoring film thickness, and stabilize deposition conditions, making it possible to form more diverse laminated films and thin films with more complex compositions with good reproducibility. It's now possible.

In the apparatus of the present invention, the partition plate may have a size that partitions only the intermediate portions of adjacent ion guns in order to prevent the flow of the ion beam from being disturbed and adhering to adjacent ion guns. For the purpose of clarifying the interface of the growing crystal, it is necessary to have a size that extends from between the ion guns to just before the surface of the substrate. Further, the present invention does not prevent simultaneous use of both a partition plate and a conventionally used shutter in order to adjust the flow of the ion beam.

〔Example〕

Specific examples of the present invention are listed below.

In this embodiment, a crystal laminate made of lead and tellurium crystals was produced using the apparatus shown in FIG. I added tellurium to it.

First, the pressure inside the crystal growth chamber is reduced to 2X 1O-6Tart or less, the substrate is heated and maintained at 50°C, and the crucible 27 is heated to 530°C.
Crucible 28 is heated to 650'C! The substrate was heated to generate a cluster ion beam and crystals were grown on the substrate. While generating a cluster ion beam, the substrate holder was counter-rotated every 120 seconds so that lead crystals and tellurium crystals were alternately stacked on half of the substrate to a thickness of 1200 cm.

The interface between the lead crystal and tellurium crystal in the crystal laminate on the resulting substrate formed a clean straight line. Furthermore, crystals from the beam generated from the adjacent ion gun did not adhere to the ion gun.

〔Effect of the invention〕

As explained above, when the crystal growth apparatus of the present invention is used, the film thickness can be highly controlled because the disturbance caused by adjusting the flow of the ion beam is small and it is not affected by the charge of other ion beams. .

By physically shielding the partition plate, the laminated interface of the crystals can be clearly set in any desired shape.As the substrate holder moves freely, the position of the laminated layers and the combination of materials to be crystallized can be freely changed. There are effects such as the ability to obtain more diverse laminated films.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention, and FIG. 2 is a schematic diagram showing an example of a conventional crystal growth apparatus. ■, 1f3---------------------- Single crystal growth chamber 2
．． 17------------ Substrate and substrate holder 3.1B--------Grown crystals 4, 5, 19.20---- - One cluster ion beam e, 7, 30.31.32 - Shutter 8.
8.21.22-----One accelerating electrode 10, 11.23
．． 24------Ionization filament 12.13
．． 25.26-----Crucible 14.15.27.2
8---Cluster ion gun patent applicant
Canon Co., Ltd. Agent Tadashi Wakabayashi Figure 1 Figure 2

Claims (2)

[Claims] (1) A crystal growth apparatus having a plurality of evaporative substance ejecting means in a crystal growth chamber and a holder for a substrate to which the evaporative substance is attached, wherein a partition plate passes between two adjacent evaporative substance ejecting means. A crystal growth apparatus characterized by being provided with. (2) The crystal growth apparatus according to claim 1, further comprising a mechanism for moving the substrate holder.