阅读说明：本技术 一种等离子体改性液膜接触潮解抛光装置及抛光方法 (Plasma modified liquid film contact deliquescence polishing device and polishing method ) 是由 黄帅 何振湘 于 2019-10-14 设计创作，主要内容包括：本发明提供了一种等离子体改性液膜接触潮解抛光装置,包括载物块、重物、抛光垫、抛光盘、第一软管、第二软管、等离子体发生装置以及微汽雾发生装置,所述抛光垫安装在所述抛光盘上表面,所述载物块设置在所述抛光盘上方,所述重物设置于所述载物块上,所述载物块和所述重物用于对可潮解晶体进行施压,所述抛光盘和所述抛光垫对应所述可潮解晶体的位置设有通孔,所述等离子体发生装置和所述微汽雾发生装置分别通过所述第一软管和所述第二软管与所述通孔连通。本发明还提供了一种等离子体改性液膜接触潮解抛光方法。本发明的有益效果如下：解决现有的潮解抛光方法中,存在的液滴驻留造成微凹坑、残留有机物难以清洗等问题。(The invention provides a plasma modified liquid film contact deliquescence polishing device which comprises a carrier block, a weight, a polishing pad, a polishing disc, a first hose, a second hose, a plasma generating device and a micro-vapor-fog generating device, wherein the polishing pad is installed on the upper surface of the polishing disc, the carrier block is arranged above the polishing disc, the weight is arranged on the carrier block, the carrier block and the weight are used for pressing deliquescent crystals, through holes are formed in the positions, corresponding to the deliquescent crystals, of the polishing disc and the polishing pad, and the plasma generating device and the micro-vapor-fog generating device are respectively communicated with the through holes through the first hose and the second hose. The invention also provides a plasma modified liquid film contact deliquescence polishing method. The invention has the following beneficial effects: the problems that micro pits and residual organic matters are difficult to clean and the like caused by liquid drop residence in the existing deliquescence polishing method are solved.)

1. The utility model provides a modified liquid film contact deliquescence burnishing device of plasma, characterized in that, including carrying thing piece (1), heavy object (2), polishing pad (4), polishing dish (5), first hose (6), second hose (7), plasma generating device (8) and little vapour and fog generating device (9), polishing pad (4) are installed polishing dish (5) upper surface, carry thing piece (1) to set up polishing dish (5) top, heavy object (2) set up in carry thing piece (1) on, carry thing piece (1) with heavy object (2) are used for putting deliquescence crystal (3) on polishing pad (4) and exert pressure, polishing dish (5) with polishing pad (4) correspond the position of deliquescence crystal (3) is equipped with the through-hole, plasma generating device (8) with little vapour and fog generating device (9) are respectively through first hose (6) with the second hose (6) are passed through (7) Communicating with said through holes, plasma and micro-mist are conveyed through said first hose (6) and said second hose (7) and sprayed on the surface of said deliquescent crystal (3).

2. The plasma-modified liquid film contact deliquescent polishing apparatus according to claim 1, wherein the plasma comprises a nitrogen plasma, an oxygen plasma, an argon plasma, a helium plasma, or the like.

3. A polishing method of a plasma modified liquid film contact deliquescence polishing device according to claim 1, comprising the following steps:

step one, carrying out pretreatment on the deliquescent crystal (3);

secondly, placing the deliquescent crystal (3) which is pretreated on the polishing pad (4), and applying pressure through a carrier block (1) and a weight (2);

step three, starting a plasma generating device (8), and adjusting discharge parameters, gas substances and gas flow according to different requirements on hydrophilic modification of the plasma; starting a micro-vapor-spray generating device (9), and selecting the liquid and the mist outlet quantity for generating the mist according to the requirements of deliquescence polishing rate and surface quality;

and fourthly, starting a control switch of the polishing disk (5) and a control switch of the carrier block (1), controlling the polishing disk (5) and the carrier block (1) to rotate, and carrying out deliquescence polishing on the surface of the pretreated deliquescent crystal (3) until the polishing is finished.

4. The method for polishing a plasma modified liquid film contacting deliquescent polishing apparatus according to claim 3, further comprising, after the fourth step:

and step five, closing all the devices, taking out the deliquescent crystal (3) after polishing, wiping the surface of the taken-out deliquescent crystal (3) clean by using a piece of lens wiping paper, and placing the deliquescent crystal in a dustless and dry place.

5. The polishing method of a plasma modified liquid film contact deliquescence polishing device according to claim 3, wherein after the plasma generating device (8) performs nitrogen gas cold plasma treatment for 8s under the conditions of 3L/min of nitrogen flow, 11kv of voltage and needle electrode discharge, the surface contact angle of the deliquescent crystal (3) is 0.

6. The polishing method of a plasma modified liquid film contact deliquescence polishing device according to claim 3 or 5, wherein the liquid for generating the micro-vapor in the micro-vapor-mist generating device (9) can be pure water or an alcohol solution liquid according to actual conditions, and the amount of mist generated is controlled within a range of 0 to 600 ml/h.

7. The method of claim 6, wherein the KDP crystal is deliquesced at a rate of 0.9 μm/min when pure water is subjected to fine fogging, an amount of fogging is 280ml/h, and a room temperature is 12.8 ℃.

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of ultra-precision machining of surfaces of deliquescent crystals, in particular to a plasma modified liquid film contact deliquescence polishing device and a polishing method.

[ background of the invention ]

In the experiments of micro-machining, medical diagnosis, inertial confinement nuclear fusion and the like at the present stage, some deliquescent optical crystals play a great role, including but not limited to LBO crystals, CBO crystals, KDP crystals, CLBO crystals and the like. Most of these deliquescent crystals are soft and brittle crystals, and are sensitive to temperature changes, prone to cracking, anisotropic, and difficult to achieve ultra-precise machining of the crystal surface. The prior deliquescent crystal ultra-precision machining has the following problems: 1) small-scale ripples on the machined surface of the SPDT cannot be avoided, the repairing difficulty of surface micro-defects is high, and the machining efficiency is low; 2) the degree of practical application of the ultra-precision grinding and traditional polishing processes is not reached, and the optical properties such as laser-induced damage threshold and the like of the deliquescent crystals can be directly influenced by the abrasive particles/iron powder and the like embedded into the crystal surfaces; 3) the ion beam polishing efficiency in a vacuum environment needs to be improved. The deliquescence polishing can avoid small-scale ripples formed on the surface by fly-cutting, no abrasive particles/iron powder are embedded into the surface of a workpiece, and the deliquescence polishing has high polishing efficiency, so that the deliquescence polishing method becomes the most potential process method for realizing nanoscale or even sub-nanoscale precision polishing at present with high quality and high efficiency.

However, the traditional deliquescent polishing process converts the contact state of water and the deliquescent crystal into the liquid drop residence of discrete micro water drops and the crystal surface, and regulates the deliquescence rate of the crystal by controlling the diameter of the water drops and the quantity of the water drops. The deliquescent crystals form micro-pits on the crystal surface when deliquesced by water droplets. Therefore, in the planarization process of deliquescent polishing of the deliquescent crystal, the liquid drop residence of the non-uniform point contact formed by the water on the surface of the workpiece can cause the continuous formation of new micro-pits, the deliquescent speed of the material is high, and the deliquescent area is uncontrollable, so that the surface roughness of the deliquescent polished deliquescent crystal stays at the nanometer level and the sub-nanometer level precision cannot be improved.

[ summary of the invention ]

The invention aims to disclose a plasma modified liquid film contact deliquescence polishing device and a polishing method, which can solve the technical problems that micro pits are caused by retention of deliquescent crystal deliquescence polishing liquid drops and residual organic matters are difficult to clean and the like in the prior art.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a plasma modified liquid film contact deliquescence polishing device comprises a carrier block, a weight, a polishing pad, a polishing disc, a first hose, a second hose, a plasma generating device and a micro-vapor-fog generating device, the polishing pad is arranged on the upper surface of the polishing disk, the object carrying block is arranged above the polishing disk, the weight is arranged on the carrier block, the carrier block and the weight are used for pressing the deliquescent crystal placed on the polishing pad, the polishing disc and the polishing pad are provided with through holes corresponding to the deliquescent crystals, the plasma generating device and the micro-vapor generating device are communicated with the through holes through the first hose and the second hose respectively, and the plasma and the micro-vapor are transmitted through the first hose and the second hose and sprayed on the surfaces of the deliquescent crystals.

Preferably, the plasma includes nitrogen plasma, oxygen plasma, argon plasma, and helium plasma.

The invention also provides a polishing method of the plasma modified liquid film contact deliquescence polishing device, which comprises the following steps:

step one, carrying out pretreatment on a deliquescent crystal;

secondly, placing the pretreated deliquescent crystal on the polishing pad, and applying pressure through a carrier block and a weight;

step three, starting a plasma generating device, and adjusting discharge parameters, gas substances and gas flow according to different requirements on hydrophilic modification of the plasma; starting a micro-vapor-spray generating device, and selecting liquid and mist outlet quantity for generating the vapor spray according to the requirements of deliquescence polishing rate and surface quality;

and fourthly, starting a control switch of the polishing disk and a control switch of the object carrying block, controlling the rotation of the polishing disk and the object carrying block, and carrying out deliquescence polishing on the surface of the pretreated deliquescent crystal until the polishing is finished.

Preferably, after the fourth step, the method further comprises:

and step five, closing all the devices, taking out the deliquescent crystal after polishing, wiping the surface of the taken-out deliquescent crystal (3) clean by using lens wiping paper, and placing the deliquescent crystal in a dust-free dry place.

Preferably, the surface contact angle of the deliquescent crystal 3 is 0 after the plasma generating device 8 performs nitrogen gas cold plasma treatment for 8s by using nitrogen gas flow rate of 3L/min, voltage of 11kv and needle electrode discharge.

Preferably, the liquid used for generating the micro-vapor in the micro-vapor-mist generating device 9 can be pure water or alcohol solution liquid according to actual conditions, and the regulation range of the mist output amount is 0 to 600 ml/h.

Preferably, the deliquescence rate of the KDP crystal is 0.9um/min when pure water generates micro-vapor fog, the fog output is 280ml/h, and the room temperature is 12.8 ℃.

The invention has the following beneficial effects: the retention mode of non-uniform point-like liquid drops between the traditional deliquescent polishing medium and the deliquescent crystal is changed into a liquid film contact mode of a uniform surface area, so that the surface quality is further improved while the deliquescent polishing efficiency is kept high, and the high-quality and high-efficiency processing of the deliquescent crystal is finally realized; modifying the surface of the deliquescent crystal to be processed into super-hydrophilicity by utilizing hydrophilic hydroxyl, hydrophilic oxygen-containing functional groups, other hydrophilic groups and the like in the plasma is the key point of converting liquid drop residence into liquid film contact; the micro vapor fog quickly forms a liquid film on the super-hydrophilic deliquescent surface to deliquesce the crystal, and then removes the deliquescent layer material under the shearing action of the polishing head, thereby realizing the contact deliquescent polishing processing of the liquid film of the deliquescent crystal; the problems that micro pits and residual organic matters are difficult to clean and the like caused by liquid drop residence in the existing deliquescence polishing method are solved.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:

FIG. 1 is a schematic structural view of a plasma modified liquid membrane contact deliquescence polishing device according to the invention;

FIG. 2 is a schematic view of a first structure of the polishing pad of the present invention with through holes;

FIG. 3 is a schematic view of a second structure of the polishing pad of the present invention with through holes.

[ detailed description ] embodiments

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, the present invention provides a plasma modified liquid film contact deliquescence polishing device, which comprises a carrier block 1, a weight 2, a polishing pad 4, a polishing disk 5, a first hose 6, a second hose 7, a plasma generator 8 and a micro-vapor-spray generator 9.

The polishing pad 4 is mounted on the upper surface of the polishing disk 5.

The object carrying block 1 is arranged above the polishing disk 5, the heavy object 2 is arranged on the object carrying block 1, and the polishing disk 5 and the object carrying block 1 are in different running conditions along with installation on different polishing machines. The carrier block 1 and the weight 2 are used for pressing the deliquescent crystal 3 placed on the polishing pad 4, the mass of the weight 2 is determined according to the material of the deliquescent crystal 3, the size of a surface to be polished and the surface quality requirement, and the weight 2 can be replaced by an air cylinder or a hydraulic cylinder.

The polishing disk 5 and the polishing pad 4 are provided with through holes 51 corresponding to the deliquescent crystal 3, the plasma generating device 8 and the micro-vapor generating device 9 are respectively communicated with the through holes through the first hose 6 and the second hose 7, and the plasma and the micro-vapor are transmitted through the first hose 6 and the second hose 7 and sprayed on the surface of the deliquescent crystal 3.

Including but not limited to nitrogen plasma, oxygen plasma, argon plasma, and helium plasma.

Referring to fig. 2, in an embodiment of the polishing disc 5, the polishing disc 5 is circular, and the plurality of through holes 51 are circular arc-shaped and concentrically arranged at equal intervals.

Referring to fig. 3, in another specific embodiment of the polishing disc 5, the polishing disc 5 is circular, the through holes 51 are long, and extension lines of central axes of the through holes 51 intersect at a center of the polishing disc 5.

Of course, the shape of the through hole 51 on the polishing disc 5 provided by the present invention is not limited to the above two shapes, and any other reasonable arrangement and shape may be adopted, which should fall within the protection scope of the present invention.

The invention also provides a polishing method of the plasma modified liquid film contact deliquescence polishing device, which comprises the following steps:

step one, carrying out pretreatment on the deliquescent crystal 3;

specifically, the size of the surface to be processed is 20X 20mm²The preform of deliquescent crystal 3 is pre-polished for 10min by a ZYP230 polisher on the surface to be polished, wherein the polishing disc is set to 60rpm, the carrier block is set to a maximum value, the carrier block is set to a maximum oscillation frequency, and deionized water is used as the polishing medium at 20 drops/min.

Secondly, placing the pretreated deliquescent crystal 3 on the polishing pad 4, and pressing the deliquescent crystal through a carrier block 1 and a weight 2;

specifically, the weight 2 has a mass of 1 kg.

Step three, starting the plasma generating device 8, and adjusting discharge parameters, gas substances and gas flow according to different requirements on hydrophilic modification of the plasma; starting a micro-vapor-fog generating device 9, and selecting the liquid and the fog output amount for generating the vapor fog according to the requirements of deliquescence polishing rate and surface quality;

specifically, the surface contact angle of the deliquescent crystal 3 is 0 after the plasma generating device 8 performs nitrogen cold plasma treatment for 8s by using nitrogen gas with the flow rate of 3L/min and the voltage of 11kv and generated by needle electrode discharge. The liquid for generating the micro-vapor fog in the micro-vapor fog generating device 9 can adopt pure water or alcohol solution liquid according to actual conditions, the regulation and control range of the mist outlet quantity is 0 to 600ml/h, specifically, the micro-vapor fog is generated in the pure water, the mist outlet quantity is 280ml/h, and the deliquescence rate of KDP crystal is 0.9um/min at the room temperature of 12.8 ℃.

It is further noted that the deliquescent crystal 3 surface is deliquesced by using a fine mist containing water, and the deliquescent crystal surface is treated with plasma having a hydrophilic modification function so that droplets of the fine mist stay on the deliquescent crystal 3 surface and come into contact with a liquid film. Finally, the deliquescent layer on the surface of the deliquescent crystal 3 is removed through the mechanical action of the polishing pad, thereby realizing the deliquescent polishing of the deliquescent crystal 3.

The surface of the deliquescent crystal is subjected to hydrophilic treatment by using plasma with a hydrophilic modification function, in particular, by changing the gas generating the plasma and the discharge parameters, such as: voltage, electrode form, etc., can regulate and control the hydrophilic and hydrophobic modification capability of the plasma. And when a vortex tube or other cooling device is used, the macroscopic temperature of the plasma can be reduced.

The contact area and thickness of the liquid film can be regulated and controlled by regulating and controlling the liquid and temperature used for generating the micro-vapor and the mist output of the micro-vapor-mist generating device, so that the deliquescence area and the deliquescence rate can be accurately controlled.

And step four, starting a control switch of the polishing disk 5 and a control switch of the object carrying block 1, controlling the polishing disk 5 and the object carrying block 1 to rotate, and deliquescing and polishing the surface of the pretreated deliquescent crystal 3 until polishing is finished.

It should be further noted that, during the polishing process, the polished surface of the deliquescent crystal 3 is detected by a white light interferometer or an atomic force microscope, and when the roughness value of the polished surface of the deliquescent crystal 3 detected by the white light interferometer or the atomic force microscope reaches a target value or does not become smaller, the polishing of the deliquescent crystal 3 is completed.

Preferably, after the fourth step, the method further comprises:

and step five, closing all the devices, taking out the deliquescent crystal 3 after polishing, wiping the surface of the deliquescent crystal 3 taken out by using a piece of lens wiping paper, and placing the deliquescent crystal in a dustless and dry place.

The invention also provides a plasma modified liquid film contact deliquescence polishing method, which utilizes the plasma to hydrophilically modify the surface of the deliquescent crystal in real time, and utilizes micro-vapor fog to form uniform surface area liquid film contact deliquescence on the modified surface, thereby overcoming the defect of non-uniform point-like liquid drop residence in the traditional deliquescence polishing. The contact area and thickness of the liquid film are regulated and controlled by controlling the hydrophilicity of the deliquescent crystal, the components of the micro-vapor fog and the water content, so that the deliquescent area and the deliquescent rate are controlled, and the surface quality of the deliquescent crystal after deliquescent polishing is improved.

The invention has the following beneficial effects: the retention mode of non-uniform point-like liquid drops between the traditional deliquescent polishing medium and the deliquescent crystal is changed into a liquid film contact mode of a uniform surface area, so that the surface quality is further improved while the deliquescent polishing efficiency is kept high, and the high-quality and high-efficiency processing of the deliquescent crystal is finally realized; modifying the surface of the deliquescent crystal to be processed into super-hydrophilicity by utilizing hydrophilic hydroxyl, hydrophilic oxygen-containing functional groups, other hydrophilic groups and the like in the plasma is the key point of converting liquid drop residence into liquid film contact; the micro vapor fog quickly forms a liquid film on the super-hydrophilic deliquescent surface to deliquesce the crystal, and then removes the deliquescent layer material under the shearing action of the polishing head, thereby realizing the contact deliquescent polishing processing of the liquid film of the deliquescent crystal; the method is simple, high in efficiency, low in cost, free of small-scale ripples, free of abrasive particle embedding, environment-friendly, high in surface roughness precision, and capable of solving the problems that micro pits and residual organic matters are difficult to clean due to liquid drop residence in the existing deliquescence polishing method.

While embodiments of the invention have been disclosed above, it is not limited to the applications set forth in the specification and the embodiments, which are fully applicable to various fields of endeavor for which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.