CN-122013320-A - Gallium oxide crystal with low impurity content and growth method thereof

CN122013320ACN 122013320 ACN122013320 ACN 122013320ACN-122013320-A

Abstract

The application discloses a gallium oxide crystal with low impurity content and a growth method thereof, belonging to the technical field of gallium oxide crystal growth. The total impurity density in the gallium oxide crystal is less than or equal to 150ppm, wherein the total noble metal impurity density is less than or equal to 100ppm, the aluminum impurity density is less than or equal to 30ppm, the zirconium impurity density is less than or equal to 30ppm, and the iron impurity density is less than or equal to 1ppm. The gallium oxide crystal has low impurity content, and can effectively improve the quality and uniformity of the gallium oxide crystal.

Inventors

ZHOU HUIQIN
ZHU CAN
DANG YIFAN
CHEN PENGLEI
LIU PENGFEI
ZHU YONGHAI
YIN GUOXIAN
FAN ZHIPENG

Assignees

山东天岳先进科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260331

Claims (10)

1. The gallium oxide crystal with low impurity content is characterized in that the total impurity density in the gallium oxide crystal is less than or equal to 150ppm, wherein the total noble metal impurity density is less than or equal to 100 ppm, the impurity density of aluminum is less than or equal to 30ppm, the impurity density of zirconium is less than or equal to 30ppm, and the impurity density of iron is less than or equal to 1ppm.
2. The low impurity content gallium oxide crystal according to claim 1, wherein the total noble metal impurities include iridium, platinum, rhodium, wherein the impurity density of iridium is 50ppm or less, the impurity density of platinum is 50ppm or less, and the impurity density of rhodium is 50ppm or less.
3. The low impurity content gallium oxide crystal according to claim 1, wherein the XRD full width at half maximum of the gallium oxide crystal is 50 arcsec or less, and/or The number of cracks larger than 10 mu m in the gallium oxide crystal is less than or equal to 1 strip/piece.
4. The low impurity content gallium oxide crystal according to claim 1, wherein the gallium oxide crystal has a total dislocation density of 10 4 /cm 2 or less.
5. The gallium oxide crystal with low impurity content according to claim 1, wherein a region with diameter of 3/4 of any cross section of the gallium oxide crystal is a central region and is an edge region except the central region, wherein the total impurity density of the central region is less than or equal to 100ppm, the total noble metal impurity density is less than or equal to 80ppm, the impurity density of aluminum is less than or equal to 5ppm, the impurity density of zirconium is less than or equal to 5ppm, and the impurity density of iron is less than or equal to 1ppm; The total impurity density of the edge area is less than or equal to 150ppm, the total noble metal impurity density is less than or equal to 100 ppm, the impurity density of aluminum is less than or equal to 30ppm, the impurity density of zirconium is less than or equal to 30ppm, and the impurity density of iron is less than or equal to 1ppm.
6. The low impurity content gallium oxide crystal according to claim 5, wherein the total noble metal impurities include iridium, platinum, rhodium, wherein the impurity density of iridium in the central region is 40ppm or less, the impurity density of iridium in the edge region is 50ppm or less, the impurity density of platinum in the central region is 40ppm or less, the impurity density of platinum in the edge region is 50ppm or less, the impurity density of rhodium in the central region is 40ppm or less, and the impurity density of rhodium in the edge region is 50ppm or less.
7. The low impurity content gallium oxide crystal according to claim 5, wherein the XRD full width at half maximum of the central region is 30 arcsec or less, the edge region full width at half maximum is 50 arcsec or less, and/or The number of cracks larger than 10 mu m in the central area is less than or equal to 0 pieces/piece, and the number of cracks larger than 10 mu m in the edge area is less than or equal to 1 piece/piece.
8. The low impurity content gallium oxide crystal according to claim 5, wherein the total dislocation density in the central region is 10 3 /cm 2 or less and the total dislocation density in the edge region is 10 4 /cm 2 or less.
9. A gallium oxide crystal growth method with low impurity content, characterized by comprising the following steps: S1, placing a noble metal crucible filled with gallium oxide powder into a furnace body, wherein a high-temperature resistant adsorption material is arranged on the outer surface of the noble metal crucible; and S2, growing gallium oxide crystals under the condition of introducing protective gas, extracting gas in the furnace body in the process of cooling the furnace body after the growth is completed, and taking out the gallium oxide crystals after the temperature in the furnace body is cooled to room temperature.
10. The method for growing gallium oxide crystals with low impurity content according to claim 1, further comprising a noble metal recovery step of conveying the gas extracted from the furnace body into a recovery tank containing an absorption medium, collecting the high-temperature resistant adsorption material and the absorption medium in the recovery tank, and separating and purifying the absorption medium to recover the noble metal.

Description

Gallium oxide crystal with low impurity content and growth method thereof Technical Field The application relates to a gallium oxide crystal with low impurity content and a growth method thereof, belonging to the technical field of gallium oxide crystal growth. Background The growth of gallium oxide crystal is completed under high temperature environment of about 1800 ℃, the gallium oxide raw material is heated to above 1790 ℃ to be melted in the crystal growth process, a specific temperature interval is maintained for a period of time to be stable, then the temperature is reduced at a slow speed to realize the crystal growth, and the stability and uniformity of the temperature in the whole process are strictly required. The crucible is used as a core carrier for melting gallium oxide raw materials, nucleation and growth of crystals, and the temperature state directly determines the growth quality, size and performance of the crystals, so that the temperature control of the crucible is a key link in the gallium oxide crystal growth process. In the existing gallium oxide crystal growth technology, a crucible is mostly made of iridium, rhodium, iridium-rhodium alloy or aluminum oxide-based composite materials, and the materials can withstand the high temperature required by crystal growth, but have higher self heat conductivity, so that heat is easily and rapidly dissipated through the crucible wall, and the following technical problems are brought: 1. The rapid dissipation of the heat of the crucible can lead to uneven distribution of a temperature field in the furnace, and a large temperature gradient is formed inside the crucible up and down and inside and outside the crucible. On one hand, the excessively large temperature gradient easily causes convection disorder of gallium oxide melt, damages a stable solid-liquid interface required by crystal growth, causes defects such as dissociation cracks, dislocation and the like in the crystal, reduces the crystal crystallization quality and even can not form a complete single crystal, and on the other hand, the uneven temperature distribution can cause inconsistent crystal growth rate, so that the gallium oxide single crystal with large size and high uniformity is difficult to prepare, and the application of the gallium oxide single crystal in a high-power device is limited. 2. The inefficient dissipation of heat can greatly increase the energy consumption of the heating system. In order to maintain the stable high-temperature state of the gallium oxide melt in the crucible, a heating mechanism (such as a medium-high frequency induction coil and a resistance heater) needs to continuously output a large amount of energy to compensate the heat dissipated by the crucible, so that the production cost of crystal growth is increased, the loss of a heating element is accelerated possibly due to overhigh heating power, the service life of equipment is shortened, and the production and maintenance cost is increased. 3. Rapid fluctuations in crucible surface temperature can exacerbate volatilization and compositional changes in the gallium oxide melt. Gallium oxide is volatile at high temperature, if crucible temperature is unstable, can lead to melt surface component unbalance, and then influence the chemometry of crystal, produces impurity defect, and volatilized gallium oxide steam still probably adheres to on furnace body part simultaneously, pollutes equipment and further influences crystal growth environmental stability, reduces crystal performance uniformity. 4. In the cooling stage after the crystal growth is finished, the heat loss of the crucible is too fast, so that huge thermal stress is generated in the crystal, and the risk of cracking the crystal is further increased. Especially, the large-size gallium oxide crystal has poor thermal conductivity, is difficult to quickly release thermal stress, is extremely easy to damage in the cooling process, and greatly reduces the production qualification rate. Accordingly, a low impurity content gallium oxide crystal growth method is now continued to reduce the impurity content and crystal defects in the gallium oxide crystal. Disclosure of Invention In order to solve the problems, the gallium oxide crystal growth method with low impurity content is provided, and after the gallium oxide crystal growth is finished, gas in the furnace body is pumped out, so that the influence of noble metal impurities in the furnace body on the quality of the gallium oxide crystal is reduced, the purity and the quality of the gallium oxide crystal are improved, and the internal integrity of the gallium oxide crystal is maintained. In one aspect of the application, a gallium oxide crystal with low impurity content is provided, wherein the total impurity density in the gallium oxide crystal is less than or equal to 150ppm, the total noble metal impurity density is less than or equal to 100 ppm, the impurity density of aluminum is less tha