CN204779912U

CN204779912U - Take LEC growth of single crystal device of dross filtration

Info

Publication number: CN204779912U
Application number: CN201520511329.4U
Authority: CN
Inventors: 李璐杰; 徐永宽; 程红娟; 司华青; 练小正; 杨丹丹; 洪颖; 郝建民; 赖占平
Original assignee: CETC 46 Research Institute
Current assignee: CETC 46 Research Institute
Priority date: 2015-07-15
Filing date: 2015-07-15
Publication date: 2015-11-18
Anticipated expiration: 2025-07-15

Abstract

The utility model relates to a take LEC growth of single crystal device of dross filtration, including the heater, the crucible holds in the palm, outer crucible, still include quartzy briquetting, the dross filter crucible, the filtration pore is crossed to several diameter 0.4 -0.6mm was opened to dross filter crucible bottom dross, carry out the several through ar gas to the LEC burner hearth and fill the gassing, the dehydration of halogen fuse -element is carried out in the evacuation, the persistently overheating technologies such as gaSb lump material that melt, net gaSb fuse -element is in filtration pore entering dross filter crucible is crossed to the dross, and the oxide dross is kept apart in the dross filter crucible, between the outer crucible, the beneficial effects are that dross filtering capability has been realized, moreover, the steam generator is simple in structure, under the prerequisite of optimizing the thermal field distribution in advance, be suitable for and grow low dislocation single crystal and can improve into brilliant rate.

Description

A kind of LEC single-crystal growing apparatus with scum filtering structure

Technical field

The utility model relates to a kind of LEC single-crystal growing apparatus, particularly a kind of LEC single-crystal growing apparatus with scum filtering structure.

Background technology

Liquid encapsulate Czochralski technique (LiquidEncapsulatedCzochralskiCrystalGrowth, LEC crystal growth) is the technology of a kind of improvement increasing insulating covering agent in traditional crystal pulling method technical foundation, is a kind of industrialized semiconductor single-crystal growth technology.In LEC method crystal growing process, the raw material of crystal growth is placed on heat fused in crucible, obtains certain superheating temperature.The seed crystal be fixed on crystal pulling rod is immersed melt from bath surface, after generating portion fusing, slowly upwards lifts seed rod, and dispelled the heat by seed rod.First the melt contacted with seed crystal obtains certain condensate depression, and crystallization occurs.Continuous lift seed rod, makes crystallisation process carry out continuously, thus realizes continuous print crystal growth.In the technology of LEC method growth GaSb monocrystalline, remnant oxygen and water vapour is usually there is in burner hearth and halogen insulating covering agent, and due to the Ga in GaSb material, Sb element has stronger metallicity, be easy under the high temperature conditions and oxygen, water vapour generation chemical reaction, generate dystectic Ga, Sb oxide dross, a large amount of theories and experimental result show, the existence of oxide dross solid particulate, easy grown interface trap, formation is mingled with, the existence of oxide inclusion greatly destroys the homogeneity of crystalline structure, due to the difference of the coefficient of expansion, its produce structural stress and produce a large amount of dislocation by matrix around, and make it constantly breed, as substrate material, this will have a strong impact on the performance of epitaxial film, therefore, by certain technology, avoid the existence of oxide inclusion, it is the effective way of growth fabricating low-defect-density GaSb monocrystalline.

Summary of the invention

In view of in LEC method GaSb Crystal Growth Technique, oxide dross and be mingled with the disadvantageous effect of result to low dislocation GaSb single crystal growing, the utility model provides a kind of Novel scum filtration, suppress the generation of dross on surface of fusant, concrete technical scheme is, a kind of LEC single-crystal growing apparatus with scum filtering structure, comprise well heater, crucible tray, outer crucible, it is characterized in that: also comprise quartzy briquetting, scum filtering crucible, scum filtering crucible is identical with outer crucible shape, the scum filtering hole of several diameter 0.4-0.6mm is opened in bottom, scum filtering crucible is positioned over outer crucible inside, make scum filtering crucible, the coaxial distribution of outer crucible, wall spacing 1-3cm, quartzy briquetting is placed at scum filtering crucible top, the draw-in groove of quartzy briquetting and scum filtering crucible is made to fix and be clamped in the inwall of outer crucible.

The beneficial effects of the utility model prevent from scum silica frost from producing at GaSb crystals to be mingled with, and cause dislocation desity to rise in value, structure is simple, under the prerequisite optimizing heterogeneity phantom in advance, is suitable for growth low dislocation monocrystalline and can improves crystal forming rate.

Accompanying drawing explanation

Fig. 1 is elevation cross-sectional view of the present utility model.

Fig. 2 is vertical view of the present utility model.

Embodiment

As shown in Figure 1, with the LEC single-crystal growing apparatus of scum filtering structure, comprise well heater 1, crucible tray 2, outer crucible 3, also comprise quartzy briquetting 4, scum filtering crucible 6, scum filtering crucible 6 is made identical with outer crucible 3 shape with quartz material, the scum filtering hole 8 of 10 diameter 0.5mm is opened in bottom, scum filtering crucible 6 is positioned over outer crucible 3 inner, make scum filtering crucible 6, the coaxial distribution of outer crucible 3, wall spacing 2cm, annular quartzy briquetting 4 is placed at scum filtering crucible 6 top, the draw-in groove 5 on the lower surface of quartzy briquetting 4 is made to fix with scum filtering crucible 6 upper surface and be clamped in the inwall of outer crucible 3, the bottom of scum filtering crucible 6 makes multiple scum filtering holes 8 that diameter is about 0.5mm, its effect stops that crucible external oxide scum silica frost flows in scum filtering crucible 6, realize scum silica frost and the spatial isolation lifting melt regions, the effect of the quartzy briquetting 4 of annular has three aspects, first, there is certain weight, prevent scum filtering crucible 6 floating from GaSb melt, second, there is structure fixed function, this kind of structure improves the stability of crucible, and realize the coaxial distribution of inside and outside quartz construction, and improve the symmetry of the radial heterogeneity phantom of crucible inside, 3rd, quartz briquetting 4 adds the surface-surface radiation of scum filtering crucible 6 outer wall and outer crucible 3 inwall, there is certain insulation effect, be beneficial to and reduce inside and outside quartz crucible radial symmetry gradient.

Deslagging process comprises,

The first step, scum filtering crucible 6 to be positioned over outer crucible 3 inner, makes scum filtering crucible 6, the coaxial distribution of outer crucible 3;

Second step, weigh GaSb polycrystalline block material pulverizing, weigh halogen insulating covering agent, above-mentioned raw materials 7 is positioned between two-layer quartz crucible, make the draw-in groove 5 of quartzy briquetting 4 fix with scum filtering crucible 6 and be clamped in the inwall of outer crucible 3;

3rd step, use Ar gas carry out several inflation/deflation to LEC burner hearth, remove most oxygen, water vapour content in burner hearth;

4th step, be warming up to about 500 degrees Celsius of fusing halogen insulating covering agents, constant temperature also continues to vacuumize and carries out the dehydration of halogen melt, until bath surface bubble-free produces, keeps the state that vacuumizes to remove water vapour;

5th step, continues to be warming up to about 700 degrees Celsius, constant temperature about 24 hours, makes remnant oxygen and water vapour and block GaSb in burner hearth expect at high temperature to react;

6th step, continue the fusing GaSb block material that heats up, pure GaSb melt enters scum filtering crucible 6 through scum filtering hole 8, and oxide dross is isolated between scum filtering crucible 6, outer crucible 3, achieves scum filtering function.

Claims

1. the LEC single-crystal growing apparatus with scum filtering structure, comprise well heater (1), crucible tray (2), outer crucible (3), it is characterized in that: also comprise quartzy briquetting (4), scum filtering crucible (6), scum filtering crucible (6) is identical with outer crucible (3) shape, the scum filtering hole (8) of several diameter 0.4-0.6mm is opened in bottom, scum filtering crucible (6) is positioned over outer crucible (3) inner, make scum filtering crucible (6), outer crucible (3) coaxial distribution, wall spacing 1-3cm, quartzy briquetting (4) is placed at scum filtering crucible (6) top, the draw-in groove of quartzy briquetting (4) (5) and scum filtering crucible (6) is made to fix and be clamped in the inwall of outer crucible (3).