CN203592407U - Device for blasting sand on back side of silicon chip to produce gettering source to eliminate oxidation fog on surface of silicon polished surface - Google Patents
Device for blasting sand on back side of silicon chip to produce gettering source to eliminate oxidation fog on surface of silicon polished surface Download PDFInfo
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- CN203592407U CN203592407U CN201320656668.2U CN201320656668U CN203592407U CN 203592407 U CN203592407 U CN 203592407U CN 201320656668 U CN201320656668 U CN 201320656668U CN 203592407 U CN203592407 U CN 203592407U
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- silicon chip
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- silicon
- conveyer belt
- back side
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Abstract
The utility model provides a device for blasting sand on the back side of a silicon chip to produce a gettering source to eliminate oxidation fog on the surface of a silicon polished surface. The device comprises a carborundum nozzle, a nozzle moving device, a dust removing wind cabinet, a silicon chip conveyor belt, a carborundum charging bucket and a first dust collecting tank, wherein the carborundum nozzle is arranged on the nozzle moving device, arranged above the silicon chip conveyor belt, and capable of moving left and right above the silicon chip conveyor belt under the action of the nozzle moving device; the dust removing wind cabinet is arranged above the silicon chip conveyor belt, extends downwards from a position above the silicon chip conveyor belt to the upper surface of the silicon chip conveyor belt; the carborundum nozzle is arranged in the dust removing wind cabinet; a through hole is formed in the top of the dust removing wind cabinet; the dust removing wind cabinet is in pipeline communication with the first dust collecting tank through the through hole; the carborundum nozzle is communicated with the carborundum charging bucket through a pipeline.
Description
Technical field
The utility model relates to IC grade silicon polished silicon wafer technical field, particularly relates to a kind of device of silicon chip back side sandblast manufacture gettering source elimination silicon polishing surface oxidation mist.
Background technology
IC grade silicon polished silicon wafer is to manufacture the core material of extensive and super large-scale integration, is mainly used in the high-tech area such as high-speed computer, Aero-Space.The microdefect " oxidation fog " of silicon single-crystal polishing plate is perplexing the quality of high reliability device silicon single-crystal polishing plate always.For a long time, people adopt several different methods to eliminate the oxidation fog on silicon polished surface.The method adopting is mainly the mode by gettering, has two kinds of intrinsic gettering and outer getterings.Intrinsic gettering is mainly to utilize the oxygen precipitation in silicon chip to produce the oxidation fog on elimination silicon polishing surface, gettering district, and because of its apparatus expensive, complex process, requires the interior oxygen precipitation profile of silicon chip even, wayward, and poor repeatability, therefore applies less at home and abroad.Outer gettering is mainly to utilize external means to form damage or stress at silicon chip back side, concrete mode has at the damage of silicon chip back side grinder belt, damage from laser or LPCVD growing polycrystalline silicon layer etc., or adopts the methods such as irradiation, heat pre-treatment, the soft damage of silicon chip back side to eliminate the oxidation fog of silicon chip.
Adopting dry abrasive blasting to manufacture the oxidation fog of eliminating silicon polishing surface in gettering source to the back side of silicon chip is emergingly in recent years a kind ofly can effectively eliminate the oxidation fog on silicon polished surface, while technique advantages of simple again, invest little, workable, easy to implement outer impurity absorption method.It is to damage gettering principle according to the back of the body, at silicon chip back side dry abrasive blasting, produce lattice damage or distortion, manufacture gettering source, by control and modulation to sand size, blasting pressure, an operation pitch of fins, time course, at the uniform stacking fault density of silicon chip back side manufacture, produce 6-38 × 104/cm at silicon chip back side
2damage fault, induce heap diamicton mistake, make silicon chip there is extrinsic gettering ability.At high temperature, the impurity of silicon chip can be shifted, and transfer to the non-critical position at silicon chip the inside and the back side, in the making integrated circuit region on polished silicon wafer surface, form the clean area of the several um of thickness, thereby the high-quality that obtains nothing " oxidation fog " is silicon polished, guarantees that IC product circuit characteristic is unaffected.
Summary of the invention
The purpose of this utility model is to provide a kind of silicon chip back side sandblast of new structure to manufacture the device of gettering source elimination silicon polishing surface oxidation mist, technical problem to be solved is to make it by diamond dust nozzle is moved left and right, can reduce the bore of diamond dust nozzle, make diamond dust even in the sprinkling of silicon chip back side, the damage that silicon chip back side sandblast forms is evenly controlled; And by dedusting wind cupboard being set outward at diamond dust nozzle, dedusting wind cupboard being communicated with dust collection tank, the dust diffusion producing can prevent sandblast time, collects recycling to diamond dust, is very suitable for practicality.
The purpose of this utility model and solve its technical problem and realize by the following technical solutions.The device of manufacturing gettering source elimination silicon polishing surface oxidation mist according to a kind of silicon chip back side sandblast the utility model proposes, it comprises: diamond dust nozzle, nozzle mobile device, dedusting wind cupboard, silicon chip conveyer belt, diamond dust batch can and the first dust collection tank; Wherein, described diamond dust nozzle is arranged on described nozzle mobile device, and is arranged at the top of described silicon chip conveyer belt, can under the effect of described nozzle mobile device, above described silicon chip conveyer belt, move left and right; Described dedusting wind cupboard is arranged at the top of described silicon chip conveyer belt, and is extended downward the upper surface of described silicon chip conveyer belt by the top of described silicon chip conveyer belt, and described diamond dust nozzle is arranged in described dedusting wind cupboard; Top at described dedusting wind cupboard is provided with through hole, and described dedusting wind cupboard passes through pipeline communication by described through hole and described the first dust collection tank; Described diamond dust nozzle is communicated with described diamond dust batch can by pipeline.
The purpose of this utility model and solve its technical problem and also can be applied to the following technical measures to achieve further.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, and wherein said diamond dust nozzle is quartz ampoule.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, and wherein said nozzle mobile device is cylinder, and described diamond dust nozzle is arranged on the piston of described cylinder.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, and the distance that wherein said diamond dust nozzle moves left and right under the effect of described nozzle mobile device above described silicon chip conveyer belt is 0-200mm.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, wherein said dedusting wind cupboard is closed wind cupboard, and is provided with observable silicon chip back side diamond dust on just to the one side of described diamond dust nozzle and sprays the organic glass door of hacking situation.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, wherein on the bearing carrier of described silicon chip conveyer belt, be provided with grid, described grid runs through the loading end of described bearing carrier and another side corresponding thereto, below described silicon chip conveyer belt, be provided with the second dust collection tank, the grid of described silicon chip conveyer belt can allow to become scattered about diamond dust on described silicon chip conveyer belt by entering described the second dust collection tank.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, and wherein said silicon chip conveyer belt is netted nylon cloth conveyer belt.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, and wherein said diamond dust batch can is provided with electromagnetic shaker.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, and wherein said electromagnetic shaker is electric vibrator.
The device of gettering source elimination silicon polishing surface oxidation mist is manufactured in aforesaid silicon chip back side sandblast, on the pipeline being wherein communicated with described the first dust collection tank at described dedusting wind cupboard, be also provided with exhaust blower, the described through hole of described dedusting wind cupboard is to be connected with the entrance of described exhaust blower by pipeline, and the outlet of described exhaust blower is to be connected with described the first dust collection tank by pipeline.
The utility model compared with prior art has obvious advantage and beneficial effect.By technique scheme, the sandblast of the utility model silicon chip back side is manufactured the device of eliminating silicon polishing surface oxidation mist in gettering source and is at least had following advantages and beneficial effect:
1, the utility model, by diamond dust nozzle is moved left and right, can reduce the bore of diamond dust nozzle, makes diamond dust even in the sprinkling of silicon chip back side, and the damage that silicon chip back side sandblast forms is evenly controlled; And by dedusting wind cupboard being set outward at diamond dust nozzle, dedusting wind cupboard being communicated with dust collection tank, the dust diffusion producing can prevent sandblast time, collects recycling to diamond dust.
2, the utility model is by adopting quartz ampoule can prevent from introducing when the sandblast new contamination as nozzle.
3, the utility model, by adopting netted conveyer belt to transport silicon chip and configure dust collection tank below conveyer belt, can be collected the diamond dust that becomes scattered about silicon chip surrounding on conveyer belt at any time, recycling.
4, the utility model is by adding electromagnetic shaker at diamond dust batch can, and the diamond dust that can make to be stored in batch can keeps rarefaction always, thereby makes by pipeline unobstructedly to the diamond dust transportation of diamond dust nozzle, and the flow velocity that diamond dust is carried is even.
Above-mentioned explanation is only the general introduction of technical solutions of the utility model, in order to better understand technological means of the present utility model, and can be implemented according to the content of description, and for above and other object of the present utility model, feature and advantage can be become apparent, below especially exemplified by preferred embodiment, and coordinate accompanying drawing, be described in detail as follows.
Accompanying drawing explanation
Fig. 1 is the structural representation that the preferred embodiment of the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in the sandblast of the utility model silicon chip back side.
The specific embodiment
Technological means and effect of taking for reaching predetermined goal of the invention for further setting forth the utility model, below in conjunction with accompanying drawing and preferred embodiment, its specific embodiment of device, structure, feature and effect thereof of silicon chip back side sandblast according to the utility model proposes being manufactured to gettering source elimination silicon polishing surface oxidation mist, be described in detail as follows.
Relevant aforementioned and other technology contents of the present utility model, Characteristic can be known and present in the following detailed description coordinating with reference to graphic preferred embodiment.By the explanation of the specific embodiment, should obtain one more deeply and concrete understanding for technological means and effect of reaching predetermined object and taking to the utility model, but appended graphic be only to provide with reference to the use of explanation, be not used for the utility model to be limited.
Referring to shown in Fig. 1, is the structural representation that the preferred embodiment of the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in the sandblast of the utility model silicon chip back side.
It is that it is mainly made up of diamond dust nozzle 1, nozzle mobile device 2, dedusting wind cupboard 3, silicon chip conveyer belt 4, diamond dust batch can 5 and the first dust collection tank 6 for silicon chip back side dry abrasive blasting being manufactured to gettering source to eliminate the oxidation fog on silicon polishing surface that the device of eliminating silicon polishing surface oxidation mist in gettering source is manufactured in silicon chip back side sandblast of the present utility model.Wherein, diamond dust nozzle 1 is arranged on nozzle mobile device 2, and is arranged at the top of silicon chip conveyer belt 4, can under the effect of nozzle mobile device 2, above silicon chip conveyer belt 4, move left and right.Dedusting wind cupboard 3 is arranged at the top of silicon chip conveyer belt 4, and is extended downward the upper surface of silicon chip conveyer belt 4 by the top of silicon chip conveyer belt 4, and diamond dust nozzle 1 is arranged in dedusting wind cupboard 3.Top at dedusting wind cupboard 3 is provided with through hole, and dedusting wind cupboard 3 passes through pipeline communication by described through hole and the first dust collection tank 6.Diamond dust nozzle 1 is communicated with diamond dust batch can 5 by pipeline.
Diamond dust nozzle 1 of the present utility model can be quartz (SiO
2) pipe, nozzle mobile device 2 can be cylinder, and now diamond dust nozzle 1 is arranged on the piston of cylinder, and the distance that diamond dust nozzle 1 moves left and right under the effect of nozzle mobile device 2 above silicon chip conveyer belt 4 can be 0-200mm.The utility model is by adopting quartz (SiO
2) pipe is as diamond dust nozzle 1, with respect to the conventional copper nozzle of prior art or stainless steel nozzle, can avoid copper nozzle or stainless steel nozzle with diamond dust Long Term Contact after wear and tear, and copper or stainless steel impurity are sprayed onto to the secondary pollution that silicon chip back side causes silicon chip back side.Meanwhile, the utility model is by quartz (SiO
2) pipe nozzle moves left and right under the effect of nozzle mobile device 2, disperse to spray diamond dust with respect to the fixed bell-shaped nozzle that prior art is conventional, the silicon chip back side damage layer that can avoid adopting bell-shaped nozzle sandblast to cause is inhomogeneous, make the damage at silicon chip 7 back sides evenly controlled, the damage layer consistent in density of the center and peripheral at silicon chip 7 back sides.
Dedusting wind cupboard 3 of the present utility model is closed wind cupboard, and is provided with observable silicon chip 7 back-side gold emery on just to the one side of diamond dust nozzle 1 and sprays the organic glass door (not shown) of hacking situations.The utility model is by the setting of dedusting wind cupboard 3, the dust producing can make diamond dust spray time is controlled effectively, avoid not arranging any cleaner in the time of the sandblast of diamond dust nozzle, or while fan housing being set above diamond dust nozzle, owing to being unlimited space between diamond dust nozzle and diamond dust conveyer belt, spray a large amount of dust from flying that diamond dust produces, enter atmosphere, cause environmental pollution.
On the bearing carrier of silicon chip conveyer belt 4 of the present utility model, can be provided with grid, described grid is to run through the loading end of bearing carrier and another side corresponding thereto, can be provided with the second dust collection tank 8 at the lower of silicon chip conveyer belt 4, wherein the grid of silicon chip conveyer belt 4 can allow to become scattered about diamond dust on silicon chip conveyer belt 4 by entering the second dust collection tank 8.Preferably, silicon chip conveyer belt 4 of the present utility model can be netted nylon cloth conveyer belt.The utility model is by adopting netted conveyer belt to transport silicon chip, and dust collection tank is set below netted conveyer belt, only can collect from conveyer belt exit the diamond dust that becomes scattered about silicon chip surrounding on conveyer belt with respect to adopting the conventional fine and close nylon cloth conveyer belt of prior art to transport silicon chip, can realize by the grid on silicon chip conveyer belt 4 collection at any time of the diamond dust to becoming scattered about silicon chip surrounding on silicon chip conveyer belt 4, recycling.
Diamond dust batch can 5 of the present utility model can be provided with electromagnetic shaker 9, store diamond dust with respect to prior art with the batch can that electromagnetic shaker is not set, again by air pressure by the diamond dust force feed in tank to diamond dust nozzle, the utility model can make diamond dust under the effect of electromagnetic shaker 9, in diamond dust batch can 5, keep rarefaction by arranging of electromagnetic shaker 9 always, avoid piling up fine and close because of diamond dust in tank, and the flow velocity that causes diamond dust to be carried is inhomogeneous, can make the diamond dust transportation from pipeline to nozzle unobstructed, flow velocity is even.Preferably, electromagnetic shaker 9 of the present utility model can be electric vibrator.
On the pipeline that the utility model is communicated with the first dust collection tank 6 at dedusting wind cupboard 3, also can be provided with exhaust blower (not shown), wherein the through hole of dedusting wind cupboard 3 is to be connected with the entrance of exhaust blower by pipeline, and the outlet of exhaust blower is to be connected with the first dust collection tank 6 by pipeline.The utility model is collected by the dust that can fly upward in the time that the silicon chip 7 on silicon chip conveyer belt 4 sprays diamond dust diamond dust nozzle 1 that arranges of the first dust collection tank 6, and the diamond dust of collecting can be reused.
The above, it is only preferred embodiment of the present utility model, not the utility model is done to any pro forma restriction, although the utility model discloses as above with preferred embodiment, but not in order to limit the utility model, any those skilled in the art, do not departing within the scope of technical solutions of the utility model, when can utilizing the technology contents of above-mentioned announcement to make a little change or being modified to the equivalent embodiment of equivalent variations, in every case be not depart from technical solutions of the utility model content, any simple modification of above embodiment being done according to technical spirit of the present utility model, equivalent variations and modification, all still belong in the scope of technical solutions of the utility model.
Claims (10)
1. a device for gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast, it is characterized in that it comprises: diamond dust nozzle, nozzle mobile device, dedusting wind cupboard, silicon chip conveyer belt, diamond dust batch can and the first dust collection tank; Wherein, described diamond dust nozzle is arranged on described nozzle mobile device, and is arranged at the top of described silicon chip conveyer belt, can under the effect of described nozzle mobile device, above described silicon chip conveyer belt, move left and right; Described dedusting wind cupboard is arranged at the top of described silicon chip conveyer belt, and is extended downward the upper surface of described silicon chip conveyer belt by the top of described silicon chip conveyer belt, and described diamond dust nozzle is arranged in described dedusting wind cupboard; Top at described dedusting wind cupboard is provided with through hole, and described dedusting wind cupboard passes through pipeline communication by described through hole and described the first dust collection tank; Described diamond dust nozzle is communicated with described diamond dust batch can by pipeline.
2. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 1, it is characterized in that wherein said diamond dust nozzle is quartz ampoule.
3. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 2, it is characterized in that wherein said nozzle mobile device is cylinder, and described diamond dust nozzle is arranged on the piston of described cylinder.
4. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 3, it is characterized in that the distance that wherein said diamond dust nozzle moves left and right under the effect of described nozzle mobile device above described silicon chip conveyer belt is 0-200mm.
5. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 4, it is characterized in that wherein said dedusting wind cupboard is closed wind cupboard, and be provided with observable silicon chip back side diamond dust on just to the one side of described diamond dust nozzle and spray the organic glass door of hacking situation.
6. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 5, it is characterized in that wherein on the bearing carrier of described silicon chip conveyer belt, being provided with grid, described grid runs through the loading end of described bearing carrier and another side corresponding thereto, below described silicon chip conveyer belt, be provided with the second dust collection tank, the grid of described silicon chip conveyer belt can allow to become scattered about diamond dust on described silicon chip conveyer belt by entering described the second dust collection tank.
7. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 6, it is characterized in that wherein said silicon chip conveyer belt is netted nylon cloth conveyer belt.
8. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 7, it is characterized in that wherein said diamond dust batch can is provided with electromagnetic shaker.
9. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 8, it is characterized in that wherein said electromagnetic shaker is electric vibrator.
10. the device of gettering source elimination silicon polishing surface oxidation mist is manufactured in silicon chip back side sandblast according to claim 9, on the pipeline that it is characterized in that being wherein communicated with described the first dust collection tank at described dedusting wind cupboard, be also provided with exhaust blower, the described through hole of described dedusting wind cupboard is to be connected with the entrance of described exhaust blower by pipeline, and the outlet of described exhaust blower is to be connected with described the first dust collection tank by pipeline.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320656668.2U CN203592407U (en) | 2013-10-23 | 2013-10-23 | Device for blasting sand on back side of silicon chip to produce gettering source to eliminate oxidation fog on surface of silicon polished surface |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320656668.2U CN203592407U (en) | 2013-10-23 | 2013-10-23 | Device for blasting sand on back side of silicon chip to produce gettering source to eliminate oxidation fog on surface of silicon polished surface |
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| Publication Number | Publication Date |
|---|---|
| CN203592407U true CN203592407U (en) | 2014-05-14 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320656668.2U Withdrawn - After Issue CN203592407U (en) | 2013-10-23 | 2013-10-23 | Device for blasting sand on back side of silicon chip to produce gettering source to eliminate oxidation fog on surface of silicon polished surface |
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| Country | Link |
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| CN (1) | CN203592407U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103846813A (en) * | 2013-10-23 | 2014-06-11 | 洛阳市鼎晶电子材料有限公司 | Device for removing oxidation fog on silicon polishing surface by impurity absorption source prepared on back of silicon wafer by sand blasting |
-
2013
- 2013-10-23 CN CN201320656668.2U patent/CN203592407U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103846813A (en) * | 2013-10-23 | 2014-06-11 | 洛阳市鼎晶电子材料有限公司 | Device for removing oxidation fog on silicon polishing surface by impurity absorption source prepared on back of silicon wafer by sand blasting |
| CN103846813B (en) * | 2013-10-23 | 2016-03-23 | 洛阳市鼎晶电子材料有限公司 | Silicon chip back side sandblasting manufactures the device that silicon polishing surface oxidation mist is eliminated in gettering source |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20140514 Effective date of abandoning: 20160323 |
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| C25 | Abandonment of patent right or utility model to avoid double patenting |