CN101275805A - Carbon dioxide supercritical drying device of semiconductor refrigeration - Google Patents
Carbon dioxide supercritical drying device of semiconductor refrigeration Download PDFInfo
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- CN101275805A CN101275805A CNA2007100648550A CN200710064855A CN101275805A CN 101275805 A CN101275805 A CN 101275805A CN A2007100648550 A CNA2007100648550 A CN A2007100648550A CN 200710064855 A CN200710064855 A CN 200710064855A CN 101275805 A CN101275805 A CN 101275805A
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Abstract
The invention discloses a carbon dioxide super-critical drying device for semiconductor refrigeration, comprising: a super-critical drying chamber for releasing a sacrificial layer, which is composed of a high pressure reaction chamber and a temperature control chamber; the high pressure reaction chamber contains a silicon chip bracket, supplies a reaction chamber of carbon dioxide replacement and gasification drying, which is connected with a carbon dioxide gas cylinder, and outer wall thereof is equipped with a semiconductor cooling ring; the temperature control chamber is connected with the high pressure reaction chamber through an evaporator pipe coil to implement refrigerating and heating of the high pressure reaction chamber; a separation decompression chamber is connected with the high pressure reaction chamber through pipeline for separating decompressed alcohol and carbon dioxide; the super-critical drying chamber is connected fixedly to the separation decompression chamber through a base support. The invention can solve the problem of adhesion of drying in micro machining, and reduce consumption of liquid carbon dioxide, so as to save energy and reduce environment pollution. Compared with carbon dioxide or Freon refrigeration, the invention has simple structure without noise and pollution and fast refrigeration speed.
Description
Technical field
The present invention relates to the sacrifice layer release tech field of MEMS (MEMS) key manufacture in the microelectric technique, relate in particular to a kind of carbon dioxide supercritical drying device of semiconductor refrigerating, when utilizing liquid CO 2 to enter supercriticality, carbon dioxide becomes and a kind ofly enters the characteristics of supercriticality like liquid like the surface tension that do not have of gas, solves the adhesion problems between the structure sheaf behind the wet etching.
Background technology
In MEMS (MEMS) manufacturing technology, the silicon substrate surface micromachining technology is an important component part, has avoided body silicon deep processing longitudinally, with integrated circuit technology better compatibility is arranged, and helps the integrated of structural devices and treatment circuit.
In silicon substrate surface micromachined process, " sacrifice layer " technology that apply to is made unsettled beam, film or cavity structure.In the sacrifice layer dispose procedure or after sacrifice layer forms, in most cases evaporating produces surface tension and causes that structure sheaf is drop-down, and this phenomenon is called adhesion phenomenon, and the CO 2 supercritical drier is to solve in the microfabrication adhesion the best way when dry.
Liquid under the supercriticality between the fine structure has just become a kind of capillary liquid (also can be called gas) that do not have, and carries out dry heat or decompression vaporization this moment again, the adhesion phenomenon that surface tension caused when the slow carburation by evaporation of liquid just can not take place.Equipment principle is based on after sacrifice layer corrosion is intact, displace pure class I liquid I in the fine structure with liquid CO 2 during low temperature, slowly heat up then and enter super critical point, it is dry to keep opening after tens of minutes valve decompression vaporization, thus the adhesion problems when solving the wet processing drying.This equipment will obviously be better than additive methods such as freeze-dried method and organic displacement based on the effect of this principle.
Scientific research institution and colleges and universities that China is engaged in the relevant microfabrication of MEMS now have more than nearly thousand families.Also there are many such research institutions in Japan Korea S.Wet processing device is simple, and the characteristics of cost cheapness also will make this numeral develop rapidly, and therefore a huge market is just arranged at present at home.And the existing CO 2 supercritical drying equipment of the U.S. adopts is carbon dioxide refrigeration, serious contaminated environment, and the use amount of carbon dioxide is very big to cause the wasting of resources.According to the United Nations's capital of a country CO2 emission agreement, the existing equipment of Japanese Korea S research institution will withdraw from the laboratory.Low carbon dioxide emission equipment is very favourable to capturing the Japanese Korea S and the Southeast Asia scientific research institution market of greenhouse effects of the earth irritation.
Summary of the invention
(1) technical problem that will solve
In view of this, main purpose of the present invention is to provide a kind of carbon dioxide supercritical drying device of semiconductor refrigerating, solving in the microfabrication problem of adhesion when dry, and reduces the consumption of liquid CO 2, reaches the purpose of energy savings.
(2) technical scheme
For achieving the above object, technical scheme of the present invention is achieved in that
A kind of carbon dioxide supercritical drying device of semiconductor refrigerating, this device comprises:
Supercritical drying chamber is used for the release of sacrifice layer, is made up of reaction under high pressure chamber 4 and temperature-controlled chamber 5; Reaction under high pressure chamber 4 is used to hold the silicon chip support, and the reative cell of carbon dioxide replacement and vaporizing and drying is provided, and links to each other with dioxide bottle, and on the outer wall of reaction under high pressure chamber 4 semiconductor refrigerating ring 201 is installed; Temperature-controlled chamber 5 links to each other with reaction under high pressure chamber 4 by evaporator coil, realizes the refrigeration and the heating of reaction under high pressure chamber 4;
Described supercritical drying chamber is fixedlyed connected by a seat stand 2 with separation decompression chamber 6.
4 tops, described reaction under high pressure chamber are equipped with high gland 1, are used for the sealed high pressure chamber.
Described high gland 1 is made by stainless steel material, and its diameter is 180mm, and height is 20mm.
Bottom, described reaction under high pressure chamber is equipped with import magnetic valve 401, outlet magnetic valve 402, temperature sensor 11, pressure sensor 10; Wherein, import magnetic valve 401 and outlet magnetic valve 402 are used to control the turnover of carbon dioxide; Temperature sensor 11 is used to test and control the temperature in the reaction under high pressure chamber 4; Pressure sensor 10 is used to test and control the pressure in the reaction under high pressure chamber 4.
Described reaction under high pressure chamber is the cylinder that stainless steel material is made, and its diameter is 135mm, and height is 82mm.
Described silicon chip props up and is placed on 4 inside, reaction under high pressure chamber, and resistive heater directly posts the bottom in reaction under high pressure chamber 4;
Described semiconductor refrigerating boxing is connected on the outer wall of reaction under high pressure chamber 4, and its internal diameter is 135mm.
Described separation decompression chamber 6 is connected to air inlet pipe and decompression exhaust pipe 8, and air inlet pipe is used to connect reaction under high pressure chamber 4 and separation decompression chamber; Decompression exhaust pipe 8 is used to get rid of residual liquid and gas.
Described separation decompression chamber is the cylinder that stainless steel material is made, and its diameter is 135mm, and height is 200mm.
Described silicon chip support is diameter 120mm, the aluminium alloy cylinder of thickness 2mm.
This device is moved automatically by relay temperature and pressure transmitter and valve control, and the safe self-locking function is set.
(3) beneficial effect
From technique scheme as can be seen, the present invention has following beneficial effect:
1, utilizes the present invention, the adhesion problems when adopting the CO 2 supercritical seasoning to solve the wet processing drying.Liquid under the supercriticality between the fine structure has just become a kind of capillary liquid (also can be called gas) that do not have, and carries out dry heat or decompression vaporization this moment again, the adhesion phenomenon that surface tension caused when the slow carburation by evaporation of liquid just can not take place.
2, utilize the present invention, adopt semiconductor refrigerating technology to replace existing carbon dioxide open refrigeration, greatly reduce the consumption of liquid CO 2, saved the energy.
3, utilize the present invention, adopt semiconductor refrigerating technology to replace existing carbon dioxide open refrigeration, consume great amount of carbon dioxide, the difficult problem of atmosphere pollution thereby overcome with the carbon dioxide open refrigeration.
4, utilize the present invention, adopt semiconductor refrigerating technology to replace existing carbon dioxide open refrigeration, compare with carbon dioxide refrigeration or freon refrigeration, simple in structure, noiselessness, pollution-free, refrigerating speed is fast.
5, utilize the present invention, increase the batch processing ability, four cun five batch processing ability of existing equipment is brought up to four cun ten batch processing ability, can single treatment ten four cun silicon chip, for industrialization is laid a good foundation.
6, the present invention adopts the pressure vessel that meets Chinese Industrial Standards (CIS), and security is higher, and the equipment operation is carried out automatically by relay temperature and pressure transmitter and valve control, and the safe self-locking function is set, and therefore greatly reduces the danger coefficient of equipment operation.
7, utilize the present invention, realize the operation automation of semiconductor refrigerating CO 2 supercritical drying equipment, the automation mechanized operation of can finalizing the design when equipment is verified out optimum state by manual operations, equipment operation by the time controlled relay and temperature and pressure transmitter and valve control carry out automatically, and the safe self-locking function is set.
Description of drawings
Fig. 1 is the structural representation of the carbon dioxide supercritical drying device of semiconductor refrigerating provided by the invention;
Fig. 2 is the schematic diagram of semiconductor refrigerating ring in the carbon dioxide supercritical drying device of semiconductor refrigerating provided by the invention;
Fig. 3 is the schematic diagram in the carbon dioxide supercritical drying device mesohigh lid cross section of semiconductor refrigerating provided by the invention;
Fig. 4 is the schematic diagram of the carbon dioxide supercritical drying device mesohigh reative cell inside of semiconductor refrigerating provided by the invention;
Fig. 5 is the schematic diagram of the carbon dioxide supercritical drying device mesohigh reative cell bottom of semiconductor refrigerating provided by the invention;
Among the figure, high gland 1, a seat stand 2, hold the support 3 of slice, thin piece, reaction under high pressure chamber 4, temperature-controlled chamber 5, separation decompression chamber 6, carbon dioxide filter core 7, decompression exhaust pipe 8, control panel 9, pressure sensor 10, temperature sensor 11, semiconductor refrigerating ring 201, screw hole 301, import magnetic valve 401, outlet magnetic valve 402.
The specific embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.
As shown in Figure 1, Fig. 1 is the structural representation of the carbon dioxide supercritical drying device of semiconductor refrigerating provided by the invention.This device is made of two cylindric chambers and temperature control equipment, and two cylindric chambers are fixedly connected by a seat stand 2.Wherein, the cylindric chamber in left side is a supercritical drying chamber, is used for the release of sacrifice layer; The cylindric chamber on right side is a separation decompression chamber, is used for alcohols and carbon dioxide separation.
Supercritical drying chamber is made up of reaction under high pressure chamber 4 and temperature-controlled chamber 5; Reaction under high pressure chamber 4 is positioned at top, is used to hold silicon chip support 3, and the reative cell of carbon dioxide replacement and vaporizing and drying is provided, and links to each other with dioxide bottle, and on the outer wall of reaction under high pressure chamber 4 semiconductor refrigerating ring 201 is installed; Temperature-controlled chamber 5 is positioned at 4 bottoms, reaction under high pressure chamber, comprises semiconductor refrigerating and heater, links to each other with reaction under high pressure chamber 4 by evaporator coil, realizes the refrigeration and the heating of reaction under high pressure chamber 4.
At the top of described reaction under high pressure chamber 4 high gland 1 is installed, is used for the sealed high pressure chamber.Described high gland 1 is made by stainless steel material, and its diameter is 180mm, and height is 20mm.As shown in Figure 3, Fig. 3 is the schematic diagram in the carbon dioxide supercritical drying device mesohigh lid cross section of semiconductor refrigerating provided by the invention.
As shown in Figure 4 and Figure 5, Fig. 4 is the schematic diagram of the carbon dioxide supercritical drying device mesohigh reative cell inside of semiconductor refrigerating provided by the invention, and Fig. 5 is the schematic diagram of the carbon dioxide supercritical drying device mesohigh reative cell bottom of semiconductor refrigerating provided by the invention.Import magnetic valve 401, outlet magnetic valve 402, temperature sensor 11 and pressure sensor 10 are installed in the bottom of described reaction under high pressure chamber.Wherein, import magnetic valve 401 and outlet magnetic valve 402 are used to control the turnover of carbon dioxide; Temperature sensor 11 is used to test and control the temperature in the reaction under high pressure chamber 4; Pressure sensor 10 is used to test and control the pressure in the reaction under high pressure chamber 4.
Control panel 9 demonstrations and control temperature are housed on the described trestle table 2, and show the pressure in the reaction under high pressure chamber 4, control panel links to each other with temperature-controlled chamber.
Described reaction under high pressure chamber is the cylinder that stainless steel material is made, and its diameter is 135mm, and height is 82mm.During fabrication, adopt the pressure vessel that meets Chinese Industrial Standards (CIS), the MIL STD that the existing equipment of the U.S. adopts does not meet Chinese pressure criteria.The reaction under high pressure chamber that this equipment adopts is the cylinder of stainless steel material, diameter 135mm, high 82mm; High gland is also selected stainless steel material for use, diameter 180mm, high 20mm; Produced like this reaction under high pressure chamber meets Chinese Industrial Standards (CIS), has strengthened the security in the experiment.
Described silicon chip props up and is placed on 4 inside, reaction under high pressure chamber, and resistive heater directly posts the bottom in reaction under high pressure chamber 4.
As shown in Figure 2, Fig. 2 is the schematic diagram of semiconductor refrigerating ring in the carbon dioxide supercritical drying device of semiconductor refrigerating provided by the invention.The semiconductor refrigerating boxing is connected on the outer wall of reaction under high pressure chamber 4, and its internal diameter is 135mm.
Semiconductor refrigerating is to utilize semi-conductive thermoelectric effect, and when direct current on two kinds of semi-conductive two ends are logical, absorb heat respectively and heat release in two ends, in heat absorbing end the evaporimeter heat abstractor is installed and just can be formed refrigerator.Compare with freon refrigeration with carbon dioxide refrigeration, simple in structure, noiselessness, pollution-free, refrigerating speed is fast.
Described separation decompression chamber is connected to air inlet pipe and decompression exhaust pipe 8, and air inlet pipe is used to connect reaction under high pressure chamber 4 and separation decompression chamber; Decompression exhaust pipe 8 is used to get rid of residual gas.
Described separation decompression chamber is the cylinder that stainless steel material is made, and its diameter is 135mm, and height is 200mm.
Described silicon chip support is diameter 120mm, the aluminium alloy cylinder of thickness 2mm.
This device is moved automatically by relay temperature and pressure transmitter and valve control, and the safe self-locking function is set.
In use, open high gland 1 earlier, sheet submounts 3 is put into reaction under high pressure chamber 4, drive main power source, panel power supply, manually opened carbon dioxide air valve, record gas cylinder weight, and the residual amount of estimation liquid gas.Begin cooling then, whole reaction under high pressure chamber 4 temperature are down to zero by freon refrigeration, temperature sensor 11 starts import magnetic valve 401 to reaction under high pressure chamber 4 feed liquor attitude carbon dioxide after arriving zero degree, pressure sensor 10 shows when reaction under high pressure chamber 4 internal pressures reach 4MPa, stops automatically flowing, after about 5 minutes, open reaction under high pressure chamber outlet magnetic valve 402, begin to replace the alcohols in the reaction under high pressure chamber 4, make it flow into separation decompression chamber 6, the time controlled relay pick up counting.Close outlet magnetic valve 402 after 30 minutes.Also close simultaneously import magnetic valve 401 after 5 minutes.Begin heating, temperature to 36 degree stops heating, and keeps a period of time, and after 5 minutes, pressure reaches 73MPa, opens outlet magnetic valve 402.Pressure decline liquid carbon dioxide all gasifies, and dry run is finished.Close gas cylinder valve, the operating desk outage, primary power source de-energizes is cleaned stainless steel and is crossed filter core, fills in service recorder.
Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. the carbon dioxide supercritical drying device of a semiconductor refrigerating is characterized in that, this device comprises:
Supercritical drying chamber is used for the release of sacrifice layer, is made up of reaction under high pressure chamber (4) and temperature-controlled chamber (5); Reaction under high pressure chamber (4) is used to hold the silicon chip support, and the reative cell of carbon dioxide replacement and vaporizing and drying is provided, and links to each other with dioxide bottle, and on the outer wall of reaction under high pressure chamber (4) semiconductor refrigerating ring (201) is installed; Temperature-controlled chamber (5) links to each other with reaction under high pressure chamber (4) by evaporator coil, realizes the refrigeration and the heating of reaction under high pressure chamber (4);
Separation decompression chamber (6) links to each other with reaction under high pressure chamber (4) by pipeline, be used for the decompression after with alcohols and carbon dioxide separation;
Described supercritical drying chamber is fixedlyed connected by a seat stand (2) with separation decompression chamber (6).
2. the carbon dioxide supercritical drying device of semiconductor refrigerating according to claim 1 is characterized in that, top, described reaction under high pressure chamber (4) is equipped with high gland (1), is used for the sealed high pressure chamber.
3. the carbon dioxide supercritical drying device of semiconductor refrigerating according to claim 2 is characterized in that, described high gland (1) is made by stainless steel material, and its diameter is 180mm, and height is 20mm.
4. the carbon dioxide supercritical drying device of semiconductor refrigerating according to claim 1 is characterized in that, bottom, described reaction under high pressure chamber is equipped with import magnetic valve (401), outlet magnetic valve (402), temperature sensor (11), pressure sensor (10); Wherein, import magnetic valve (401) and outlet magnetic valve (402) are used to control the turnover of carbon dioxide; Temperature sensor (11) is used for the temperature in test and the control reaction under high pressure chamber (4); Pressure sensor (10) is used for the pressure in test and the control reaction under high pressure chamber (4).
5. according to the carbon dioxide supercritical drying device of claim 1 or 4 described semiconductor refrigeratings, it is characterized in that described reaction under high pressure chamber is the cylinder that stainless steel material is made, its diameter is 135mm, and height is 82mm.
6. the carbon dioxide supercritical drying device of semiconductor refrigerating according to claim 1 is characterized in that,
Described silicon chip props up and is placed on inside, reaction under high pressure chamber (4), and resistive heater directly posts the bottom in reaction under high pressure chamber (4);
Described semiconductor refrigerating boxing is connected on the outer wall of reaction under high pressure chamber (4), and its internal diameter is 135mm.
7. the carbon dioxide supercritical drying device of semiconductor refrigerating according to claim 1 is characterized in that, described separation decompression chamber (6) is connected to air inlet pipe and decompression exhaust pipe (8), and air inlet pipe is used to connect reaction under high pressure chamber (4) and separation decompression chamber; Decompression exhaust pipe (8) is used to get rid of residual liquid and gas.
8. according to the carbon dioxide supercritical drying device of claim 1 or 7 described semiconductor refrigeratings, it is characterized in that described separation decompression chamber is the cylinder that stainless steel material is made, its diameter is 135mm, and height is 200mm.
9. the carbon dioxide supercritical drying device of semiconductor refrigerating according to claim 1 is characterized in that, described silicon chip support is diameter 120mm, the aluminium alloy cylinder of thickness 2mm.
10. the carbon dioxide supercritical drying device of semiconductor refrigerating according to claim 1 is characterized in that, this device is moved automatically by relay temperature and pressure transmitter and valve control, and the safe self-locking function is set.
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| Application Number | Priority Date | Filing Date | Title |
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| CNA2007100648550A CN101275805A (en) | 2007-03-28 | 2007-03-28 | Carbon dioxide supercritical drying device of semiconductor refrigeration |
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| CNA2007100648550A CN101275805A (en) | 2007-03-28 | 2007-03-28 | Carbon dioxide supercritical drying device of semiconductor refrigeration |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103064440A (en) * | 2012-11-30 | 2013-04-24 | 中国航空工业集团公司北京长城计量测试技术研究所 | Fluid pressure adjusting device and adjusting method based on semiconductor cooler |
| CN105943146A (en) * | 2016-05-14 | 2016-09-21 | 苏州苏南捷迈得医疗器械有限公司 | Shape-memory alloy bone fixation plate cooling machine |
-
2007
- 2007-03-28 CN CNA2007100648550A patent/CN101275805A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103064440A (en) * | 2012-11-30 | 2013-04-24 | 中国航空工业集团公司北京长城计量测试技术研究所 | Fluid pressure adjusting device and adjusting method based on semiconductor cooler |
| CN103064440B (en) * | 2012-11-30 | 2015-07-22 | 中国航空工业集团公司北京长城计量测试技术研究所 | Fluid pressure adjusting device and adjusting method based on semiconductor cooler |
| CN105943146A (en) * | 2016-05-14 | 2016-09-21 | 苏州苏南捷迈得医疗器械有限公司 | Shape-memory alloy bone fixation plate cooling machine |
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