Auxiliary monitoring system suitable for high-temperature oxide crystal growth

Abstract

The invention relates to an auxiliary monitoring system suitable for high-temperature oxide crystal growth. The system comprises a seed crystal clamping unit, a growing furnace and a capacitance monitoring unit, wherein the seed crystal clamping unit is used for clamping seed crystals; the growing furnace is insulated with the seed crystal clamping unit and the seed crystals and is used for accommodating a melt for growing the crystal; one end of the capacitance monitoring unit is connected to the seed crystal clamping unit while the other end of the capacitance monitoring unit is connected to the growing furnace; and the capacitance monitoring unit is used for monitoring capacitance values changed along with the change of relative proportion of the crystal body to the melt to output a capacitance signal. During the growth of the crystal, the proportion of the crystal body and the melt is continuously changed; and because of different dielectric constants of the melt body and the crystal body, the capacitance values measured during the growth of the crystal body are different, so that dielectric constants of a mixture of the crystal body and the melt can be monitored in real time by monitoring the capacitance values so as to deduce the proportion of the crystal body and the melt; and the growth condition of the crystal body can be fed back immediately to a certain extent, so that the growth condition of the crystal body can be monitored in an assisting mode.

Description

technical field [0001] The invention belongs to crystal growth monitoring technology, and relates to a monitoring system for the crystal growth process in a single crystal furnace. In particular, it relates to a system and method for monitoring the growth of high temperature oxide crystals using changes in capacitance signals. Background technique [0002] So far, the feedback monitoring of crystal growth processes such as the pulling method, the Kyropoulos method, and the co-solvent method mainly adopts two methods: optical hole observation method and weighing method. The optical hole observation method is a monitoring method that reflects the crystal growth status by constructing one or more optical paths from the outer furnace shell directly to the crystal growth area, and collecting image information in the furnace through human eyes or CCD. plays a vital role in. At present, in crystal growth processes such as the pulling method, the Kyroplasty method, and the co-solv...

AI Technical Summary

Problems solved by technology

Opening up the observation light path needs to penetrate the multi-layer heat shield, so the placement of the observation hole will inevitably cause a sudden change in the local heat insulation environment, thus destroying the symmetry of the temperature field

In order to reduce such damage as much as possible, the size of the observation hole will generally be made as small as possible, which will cause the inconvenience of observation and the limitation of the observation range, and the feedback information of the observation hole will also be greatly reduced.

For example, in the growth process of kyropoulos sapphire crystal, due to its small size, the observation hole can only provide useful image information in the seeding stage

On the other hand, under high temperature conditions, the melt and heating body radiate strong light. For translucent oxide crystal materials, the interference of strong light will reduce the contrast of the collected image, further limiting the reliability of the collected image data.

During the growth process, it may be due to the inconvenience of observation, which may lead to crystal growth errors, affect the quality of the crystal, and may cause accidents in severe cases

[0004] There are many deficiencies in the current observation hole method in monitoring the growth of high temperature oxide crystals

Images