CN117238752B - Device and method for eliminating surface color spots of semiconductor polishing sheet - Google Patents
Device and method for eliminating surface color spots of semiconductor polishing sheet Download PDFInfo
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- CN117238752B CN117238752B CN202311498465.XA CN202311498465A CN117238752B CN 117238752 B CN117238752 B CN 117238752B CN 202311498465 A CN202311498465 A CN 202311498465A CN 117238752 B CN117238752 B CN 117238752B
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Abstract
The invention discloses a device and a method for eliminating surface color spots of a semiconductor polishing sheet, and belongs to the field of semiconductor material processing. The device is provided with: the device comprises a reaction chamber, an ultraviolet light source assembly, an ozone circulating system and a rotating mechanism; the reaction chamber consists of an upper reflecting plate, a lower reflecting plate and a reflecting chamber, wherein the upper reflecting plate and the lower reflecting plate are respectively and hermetically connected with the side wall of the reaction chamber, and the upper part and the lower part of the side wall of the reflecting chamber are respectively connected with an ozone circulating system through airtight valves and sealed pipelines; the ultraviolet light source component comprises an ultraviolet light source array arranged in the reaction chamber and an ultraviolet light power controller for controlling the irradiation light intensity and time; the rotating mechanism comprises a flower basket clamping table, a driving motor and a rolling shaft, wherein the rolling shaft is arranged on the flower basket clamping table and is in friction contact with the edge of a polishing sheet in the flower basket; the driving motor drives the rolling shaft to rotate so as to drive the polishing sheet to rotate. The method removes the color spots on the surface of the polished wafer through ultraviolet array and ozone circulation.
Description
Technical Field
The invention relates to a device and a method for eliminating surface color spots of a semiconductor polishing sheet, belonging to the field of semiconductor material processing.
Background
Along with the gradual reduction of the line width process of an integrated circuit, the requirements on the surface cleanliness of a semiconductor polishing sheet are higher and higher, the semiconductor polishing sheet generally undergoes steps such as slicing of a crystal bar, chamfering of edges, grinding, corrosion, heat treatment, polishing and the like, and an appropriate cleaning process is required to be introduced in each step, and taking a silicon single crystal polishing sheet as an example, the surface of a polished silicon wafer presents a mirror image state with excellent surface flatness, and a final cleaning is generally required before wafer delivery.
The cleaning process and technology are introduced to remove organic and inorganic contamination on the surface of the silicon wafer, and nevertheless, the residues of chemicals used for cleaning the silicon wafer, metal ions, water vapor in the clean room air and organic and inorganic components can still bring about the surface contamination of the silicon wafer. Taking RCA cleaning process as an example, the used SC-1 liquid cleaning polishing sheet can remove organic contamination and certain metal contamination, the used SC-2 liquid has extremely strong oxidizing property and complexing property, can react with metal to generate salt to be removed along with deionized water washing, and oxidized metal ions and chloride ions to generate soluble complex to be removed along with deionized water washing. The SC-1 solution is contaminated into water-soluble compounds through the strong oxidizing property of hydrogen peroxide and the dissolution of ammonia water, metal ions such as chromium, copper, zinc, silver, nickel, cobalt, calcium, iron, magnesium and the like can be oxidized into high-valence ions, the high-valence ions are further reacted with alkali to generate soluble complex compounds which are removed along with the flushing of deionized water, the surface of the silicon wafer forms a hydrophilic oxide film with the thickness of about 6nm due to the oxidizing effect of the hydrogen peroxide, the oxide film is corroded by the ammonia water, and the oxidation and corrosion reactions are repeatedly carried out, so that particles attached to the surface of the silicon wafer are stripped, and Si on the outermost layer of the silicon wafer after SC-1 cleaning almost takes H bonds as a terminal structure to present hydrophobicity. The SC-2 solution is hydrogen peroxide and hydrochloric acid, the acidic solution has stronger capability of removing metal ions on the surface of the wafer, and after SC-2 cleaning, most of surface Si forms a layer of natural oxide film with the thickness of 0.5nm by taking O bond as a terminal structure to show hydrophilicity. The final step is dehydration and drying, and the dehydration and drying effects are achieved by utilizing the surface tension between the isopropyl alcohol and the surface of the silicon wafer according to the Marangoni effect.
However, after the SC-2 solution is used for cleaning, all areas on the surface of the silicon wafer are not completely shaped into Si-O bonds, the local area is still hydrophobic, isopropyl alcohol (IPA) is used as an organic matter, the material which is finally contacted with the wafer in the final cleaning process, and vacancy clusters on the surface of the silicon wafer are dissolved in ammonia water, so that the micro roughness of the surface of the silicon wafer is poor, trace IPA is easy to be attached, impurities in the air are slowly adsorbed in the subsequent transportation process, and the silicon wafer generally presents color spots developing from edges to the center under a strong light.
The color spot phenomenon commonly exists in the field of crystal processing and manufacturing, and the color spot phenomenon of the silicon material is not only generated on a polished wafer of a silicon wafer substrate, but also on the surface of an epitaxial wafer. The color spots are usually caused by chemical residues, metal ion pollution, deionized water influence and environmental pollution. The existing method for reducing the color spots mainly reduces the frequency and degree of the color spots by changing the means of cleaning process time, temperature, components, tool shape, factory atmosphere cleanliness, packaging cleanliness and the like, but can not completely and effectively prevent the color spots from appearing on the silicon wafers in the batch production process, the time length of the color spots is different, and the time length of the color spots is two or three days for several months, even if the silicon wafers which are qualified in inspection are shipped to a client side, the color spots on the surface of the polished surface still appear along with the time. This color spot phenomenon over time is referred to in the industry as "time haze" and, in this regard, is a major issue for upstream substrate supply ends. However, manufacturers often take measures such as optimizing process parameters, enhancing cleaning processes, controlling wafer storage conditions, etc., to mitigate or prevent the blurring of the wafer surface, which are difficult to fundamentally address the generation of time mist.
Disclosure of Invention
In view of the above problems in the prior art, an object of the present invention is to provide a device for removing color spots on the surface of a semiconductor polishing sheet, by which a high-quality oxide film can be formed on the surface of the polishing sheet to achieve perfect hydrophilicity and the surface roughness of the polishing sheet can be improved, and organic matters on the surface of the polishing sheet can be directly decomposed by ultraviolet irradiation, thereby removing the color spots.
Another object of the present invention is to provide a method for eliminating surface stains on a semiconductor polishing sheet using the apparatus, which eliminates a contamination source by removing residual compounds from the surface of the semiconductor polishing sheet by using an ultraviolet array and ozone circulation.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
an apparatus for removing surface irregularities of a semiconductor polishing sheet, the apparatus comprising: the device comprises a reaction chamber, an ultraviolet light source assembly, an ozone circulating system and a rotating mechanism; wherein,
the reaction chamber consists of an upper reflecting plate, a lower reflecting plate and a reflecting chamber, wherein the upper reflecting plate and the lower reflecting plate are respectively and hermetically connected with the side wall of the reaction chamber, the upper part and the lower part of the side wall of the reflecting chamber are respectively provided with an ozone vent for connecting an ozone circulating system, and the ozone vents are connected with the ozone circulating system through airtight valves and sealing pipelines;
the ultraviolet light source assembly comprises an ultraviolet light source array and an ultraviolet light power controller, and the ultraviolet light source array is arranged in the reaction chamber and is positioned above the flower basket; the ultraviolet light power controller controls the irradiation light intensity and the irradiation time of the ultraviolet light source array;
the rotating mechanism comprises a flower basket clamping table, a driving motor and a rolling shaft, wherein the rolling shaft is arranged on the central line of the flower basket clamping table and forms friction contact with the edge of polishing sheets arranged in the flower basket; the driving motor is connected with the roller, and when the driving motor works, the roller is driven to rotate, so that the polishing sheets in the flower basket are driven to rotate.
In the device, the ozone circulating system comprises an ozone generating unit, an ozone concentration controller and an ozone absorber, wherein the ozone generating unit and the ozone absorber are respectively connected with a reaction chamber through a sealing pipeline to form a closed loop, so that the circulation of ozone and the collection of residual ozone are realized; the ozone concentration controller is used for adjusting the concentration of the generated ozone in unit time of the ozone generating unit.
The ozone generating unit includes but is not limited to the use of corona discharge or ultraviolet irradiation oxygen method to generate ozone, but also can directly use an exogenous ozone source. When the ozone generating unit generates ozone by using a corona discharge method, the gas is pure oxygen, and a nitrogen oxide absorber is added when the gas source is air, so that nitrogen oxide is prevented from polluting the polishing sheet.
In the device of the invention, the ultraviolet light source array is arranged right above the flower basket and is spaced from the top of the edge of the polishing sheet by less than 10cm.
In the device, the ultraviolet light source array is formed by arranging ultraviolet light emitting light sources with multi-component wavelengths, the interval between adjacent light sources is less than or equal to 1cm, and at least 3 light sources are arranged above each flower basket.
In the device, the ultraviolet light emitting source uses a mercury lamp, an ultraviolet light emitting diode or a xenon lamp, and the wavelength of the light source covers UVA (long wave ultraviolet), UVB (medium wave ultraviolet) and UVC (short wave ultraviolet), wherein the wavelength of ultraviolet light emitted by the UVA is 320-400nm, the wavelength of ultraviolet light emitted by the UVB is 275-320nm, the wavelength of ultraviolet light emitted by the UVC is 200-275nm, and the irradiation intensity is more than 1.5mW/cm 2 。
In the device, the reaction chamber is made of glass, polypropylene or polytetrafluoroethylene, and the inner surface of the reaction chamber is provided with an ultraviolet diffuse reflection layer, namely an upper reflection plate, a lower reflection plate and the inner wall of the reflection chamber are all coated with ultraviolet diffuse reflection materials.
In the device, in the rotating mechanism, a motor shaft of a driving motor is rigidly connected with a roller, rubber is coated on the surface of the roller, and good friction contact is formed between the rubber and the edge of a polishing sheet; the rotational speed of the motor shaft is controlled by a controller.
A method for eliminating surface stains on a semiconductor polished wafer using the apparatus, comprising the steps of:
(1) The polishing sheets are placed in the flower basket clamping grooves, the polishing sheets in the flower basket are driven by the rolling shafts to do rotary motion, and the rotary speed is set to be at least one turn in the process time; the process time refers to the time of processing irradiation treatment for different types of products;
(2) The ozone circulation is started after the reaction chamber is sealed, and the irradiation intensity of ultraviolet light is kept to be more than 1.5mW/cm in the process 2 ；
(3) The irradiation intensity wavelength components and the irradiation time of the ultraviolet array in the irradiation process are regulated according to the material and the doping type of the polished wafer, and the irradiation time is within 30s-10min, so that the surface damage of the polished wafer is avoided;
(4) After the irradiation is completed, the air valve is switched to the ozone absorption pipeline, and the circulation pumping time is at least one time according to the pumping capacity.
In the method of the invention, the rotating mechanism drives the polishing sheet to rotate at a speed of 1-60rpm.
The invention has the advantages that:
the device for eliminating the surface color spots of the polishing sheet is particularly designed with the ultraviolet light-emitting light source equipment with various wavelengths which are alternately arranged in an array, the polishing sheet is subjected to uniform rotation and oxidation treatment of receiving illumination and ozone circulation in a reaction chamber, an ozone collecting loop is introduced to realize ozone tail gas treatment, the device is adopted to carry out surface treatment, the surface roughness of a sample is reduced, the surface particles are obviously less than those of a color spot polishing sheet, the phenomenon of the surface color spots treated by the device is not generated any more by visual inspection, the reworking of the polishing sheet due to the color spots is avoided, and the production efficiency is improved. Because polishing sheets of different materials, doping agents and polishing sheets with different doping concentrations receive ultraviolet irradiation with different light intensities, wavelengths and components and have different properties shown by ozone oxidation, the invention can better meet the process window matching exploration of the surface treatment of polishing sheets with different specifications.
Drawings
Fig. 1 is a partially exploded perspective view of the device of the present invention.
Fig. 2 is a schematic structural diagram of an ultraviolet light source array in the device of the present invention.
Fig. 3 is a perspective view of a support member in an ultraviolet light source array.
FIG. 4 is a schematic view of the reaction chamber in the apparatus of the present invention.
Fig. 5 is a schematic structural view of a rotating mechanism in the device of the present invention.
Detailed Description
The invention is further described with reference to the drawings and examples, which are not meant to limit the scope of the invention.
As shown in fig. 1 to 3, the device for eliminating the surface color spots of the semiconductor polishing sheet of the present invention comprises a reaction chamber, an ultraviolet light source assembly, an ozone circulation system and a rotation mechanism, wherein, as shown in fig. 1, the reaction chamber is composed of an upper reflecting plate 1, a lower reflecting plate 5 and a reflecting chamber 3, and the ultraviolet light source assembly comprises an ultraviolet light source array 2 arranged in the reaction chamber and an ultraviolet light power controller (not shown in the figure) for controlling the irradiation light intensity and the irradiation time, and is used for emitting ultraviolet light with proper wavelength to irradiate the surface of the polishing sheet. The rotation mechanism 6 is disposed above the lower reflecting plate 5 inside the reaction chamber for driving the polishing sheet (silicon wafer) 8 in the basket 4 to rotate. The reflection chamber 3 is provided with an ozone vent 3-2 for connection of an ozone circulation system at the upper and lower parts of the side wall thereof, respectively, for mounting an airtight valve 7, and is connected with the ozone circulation system through a sealing pipeline by the airtight valve 7. Since ozone has a molecular weight greater than that of air, it is preferable that an input port and an output port for ozone are provided on the side wall of the reflection chamber in such a manner as to go up and down.
As shown in FIG. 2, the ultraviolet light source array 2 is formed by arranging ultraviolet light emitting light sources 2-2 with multi-component wavelengths in corresponding grooves 2-3 on a supporting component 2-1, preferably, the interval between adjacent light sources is less than or equal to 1cm, and at least 3 light sources are arranged above each flower basket. The ultraviolet light source array 2 is arranged right above the flower basket, and the distance from the top of the edge of the silicon wafer 8 is smaller than 10cm. Ultraviolet light emitting sources include, but are not limited to, mercury lamps, ultraviolet light emitting diodes, or xenon lamps. The light source wavelength covers UVA, UVB, UVC, wherein the UVA-emitted ultraviolet light wavelength is between 320 and 400nm, the UVB-emitted ultraviolet light wavelength is between 275 and 320nm, and the UVC-emitted ultraviolet light wavelength is between 200 and 275nm. The ultraviolet light power controller can control the passage of each light source for controlling the ultraviolet light luminous intensity and the irradiation time, and the irradiation intensity is generally more than 1.5mW/cm 2 . As shown in fig. 3, an ultraviolet reflecting layer is disposed on the surface of the groove 2-3, and a cooling water pipe may be disposed inside the supporting member for controlling the cooling temperature of the ultraviolet light source.
As shown in fig. 1 and 4, the upper and lower reflection plates 1 and 5 are hermetically connected to the side walls of the reflection chamber 3 to prevent ozone leakage. For example, grooves may be formed in the inner surfaces of the top and bottom side walls of the reflective cavity 3, sealing washers 3-1 may be disposed in the grooves, and the upper and lower reflective plates may be respectively fitted into the corresponding grooves to achieve sealing connection between the upper and lower reflective plates 1 and 5 and the reflective cavity 3. The material of the reaction chamber can be glass, polypropylene or polytetrafluoroethylene, and has good ultraviolet light resistance and ozone oxidation resistance. Ultraviolet diffuse reflection materials are laid on the inner walls of the reflection cavity and the upper and lower reflection plates.
As shown in fig. 1 and 5, the rotating mechanism 6 includes a basket clamping table 6-1, a driving motor (not shown in the drawings), and a roller 6-2, wherein the basket clamping table 6-1 and the roller 6-2 may be mounted on the upper surface of the lower reflecting plate 5 or may be mounted at a position above the lower reflecting plate at a certain distance. The basket clamping table 6-1 is used for clamping and placing a silicon wafer basket, is stepped, has the base width of the silicon wafer basket 4 which is adaptive to the silicon wafer basket including but not limited to 4, 5, 6, 8 and 12 inches, and the rolling shaft 6-2 is arranged on the central line of the basket clamping table 6-1 and is in friction contact with the edge of the polishing piece, the driving motor is connected with the rolling shaft, and when the driving motor works, the rolling shaft is driven to rotate, and the rolling shaft is in friction contact with the edge of the polishing piece so as to drive the silicon wafer in the basket to rotate. In the rotating mechanism 6, a motor shaft of the driving motor is rigidly connected with the roller 6, rubber is laid on the surface of the roller to form good friction contact with the edge of the polished wafer, the rotating speed of the driving motor can be controlled by the controller, and the roller rotates to drive the silicon wafer to rotate in the flower basket, so that the polished surface of the silicon wafer uniformly receives ultraviolet irradiation.
The ozone circulating system used in the device comprises an ozone generating unit, an ozone concentration controller and an ozone absorber, wherein the ozone generating unit and the ozone absorber are respectively connected with a reaction chamber through a sealing pipeline to form a closed loop, so that the circulation of ozone and the collection of residual ozone are realized, and the ozone concentration controller is used for adjusting the concentration of the generated ozone in unit time of the ozone generating unit. And when the reaction is finished, the sealing pipeline conducts the reaction chamber and the ozone absorber to form a loop, and the sampling collector pumps the gas in the reaction chamber into the absorption tank through the circulating pump to collect residual ozone. The absorption liquid in the absorption tank consists of saturated sodium thiosulfate. Ozone generating units include, but are not limited to, ozone generation using corona discharge or ultraviolet irradiation of oxygen, and an exogenous ozone source may also be used. When ozone is generated by adopting a corona discharge method, the gas is pure oxygen, and a nitrogen oxide absorber is added when the gas source is air, so that nitrogen oxide is prevented from polluting the polishing sheet.
The device is used for placing the finally cleaned silicon wafer in a reaction chamber, receiving ozone oxidation and ultraviolet irradiation, forming a compact perfect silicon oxide layer on the surface of the silicon wafer, thereby being capable of isolating the adsorption of external pollutants, forming a silicon oxide layer on the surface of the silicon wafer to achieve perfect hydrophilicity through an ultraviolet light modification technology, improving the surface roughness of the silicon wafer, and directly decomposing organic matters on the surface of the silicon wafer through ultraviolet irradiation, so that the color spots are eliminated.
Furthermore, the invention is suitable for processing the surface of the silicon wafer to eliminate the color spots by adjusting the technical parameters such as the wavelength, the irradiation time, the irradiation intensity, the ozone concentration, the ventilation time and the like of the light source. The method for eliminating the color spots on the surface of the silicon wafer by using the device comprises the following steps:
(1) Placing the silicon wafer in a basket clamping groove, and driving the silicon wafer in the basket to do rotary motion by a roller, wherein the rotary speed is 1-60rpm, and at least one rotation in the process time is ensured;
(2) The ozone circulation is started after the reaction chamber is sealed, and the irradiation intensity of ultraviolet light is kept to be more than 1.5mW/cm in the process 2 ；
(3) The irradiation intensity wavelength component and the irradiation time of the ultraviolet array in the irradiation process are regulated according to the silicon wafer materials and doping types, and the irradiation time is within 30s-10min, so that the surface damage of the silicon wafer is avoided;
(4) After the irradiation is completed, the air valve is switched to the ozone absorption pipeline, and the circulation pumping time is at least one time according to the pumping capacity.
The following is an example of a practical operation of the surface stain removal process using the device:
and placing the cleaned silicon wafer into a flower basket, placing a flower basket clamp in a clamping groove of a flower basket clamping table arranged on a lower reflecting plate, enabling the edge of the silicon wafer to be in contact with a rolling shaft, buckling a reflecting cavity with the lower reflecting plate, and buckling an upper reflecting plate with the reflecting cavity of the reaction chamber after an ultraviolet light source array is arranged on the upper part of the reflecting cavity. At the moment, the circulating pump is started, the circulating valve at the other side of the reaction chamber is closed, the barometer displays negative pressure, and the reaction chamber forms better air tightness. At the moment, the circulating pump is closed, the circulating valve is opened, and the ozone circulating system is opened. The circulation time is calculated according to the volume of the reaction chamber divided by the circulation flow, at the moment, the ultraviolet light source array is started, and the irradiation intensity is more than 1.5mW/cm 2 The irradiation time is longer than 10s (seconds). After the process time is finished, the ultraviolet light is closed, the ozone generator is closed, the ozone circulating pipeline is closed, the ozone collecting pipeline is opened, the reaction time is calculated by dividing the volume of the reaction chamber by the circulating flow, and the chemical reaction formula in the ozone collecting tank is as follows: 2Na 2 S 2 O 3 +4O 3 →2Na 2 SO 4 +4O 2 Ozone is reduced into oxygen by the reducing agent, the gas absorption output is the same, and the pressure in the reaction chamber is not easy to open the upper reflecting plate.
And (3) hermetically packaging the sample subjected to the surface process and the sample not subjected to the surface process according to a normal packaging flow, standing for a period of time, and unpacking the package and adopting a strong light to irradiate the surface of the silicon wafer to visually inspect the color spots. The result shows that the phenomenon of the surface color spots treated by the process of the invention does not appear any more, the reworking of the silicon wafer due to the color spots is avoided, and the production efficiency is improved. Because the silicon wafers with different materials, dopants and doping concentrations receive the ultraviolet radiation with different light intensities, wavelengths and components and the properties shown by ozone oxidation are different, the invention can better meet the matching exploration of process windows for eliminating color spots of the silicon wafers with different specifications.
Claims (10)
1. An apparatus for removing surface irregularities from a semiconductor polishing sheet, comprising: the device comprises a reaction chamber, an ultraviolet light source assembly, an ozone circulating system and a rotating mechanism; wherein,
the reaction chamber consists of an upper reflecting plate, a lower reflecting plate and a reflecting chamber, wherein the upper reflecting plate and the lower reflecting plate are respectively and hermetically connected with the side wall of the reaction chamber, the upper part and the lower part of the side wall of the reflecting chamber are respectively provided with an ozone vent for connecting an ozone circulating system, and the ozone vents are connected with the ozone circulating system through airtight valves and sealing pipelines;
the ultraviolet light source assembly comprises an ultraviolet light source array and an ultraviolet light power controller, and the ultraviolet light source array is arranged in the reaction chamber and is positioned above the flower basket; the ultraviolet light power controller controls the irradiation light intensity and the irradiation time of the ultraviolet light source array;
the rotating mechanism comprises a flower basket clamping table, a driving motor and a rolling shaft, wherein the rolling shaft is arranged on the central line of the flower basket clamping table and forms friction contact with the edge of polishing sheets arranged in the flower basket; the driving motor is connected with the roller, and when the driving motor works, the roller is driven to rotate, so that the polishing sheets in the flower basket are driven to rotate.
2. The apparatus for removing surface stains from a semiconductor polishing sheet according to claim 1, wherein the ozone circulation system comprises an ozone generating unit, an ozone concentration controller and an ozone absorber, wherein the ozone generating unit and the ozone absorber are respectively connected with the reaction chamber through a sealing pipeline to form a closed loop, so that ozone circulation and residual ozone collection are realized; the ozone concentration controller is used for adjusting the concentration of the generated ozone in unit time of the ozone generating unit.
3. The apparatus for removing surface stains from a semiconductor polishing sheet according to claim 2, wherein the ozone generating unit irradiates ozone using an oxygen method or a corona discharge method using ultraviolet rays, or directly uses an external ozone source.
4. The apparatus for removing surface mottle from a semiconductor polishing sheet as recited in claim 1, wherein said array of ultraviolet light sources is spaced less than 10cm from the top edge of the polishing sheet.
5. The apparatus for removing surface stains from semiconductor polishing sheets as recited in claim 1, wherein the ultraviolet light source array is formed by arranging ultraviolet light emitting light sources of multiple wavelengths, the spacing between adjacent light sources is less than or equal to 1cm, and at least 3 light sources are placed above each basket.
6. The apparatus for removing surface mottle of a semiconductor polishing sheet according to claim 5, wherein said ultraviolet light-emitting light source is a mercury lamp, an ultraviolet light-emitting diode or a xenon lamp, and the light source has a wavelength coverage UVA, UVB, UVC, wherein the ultraviolet light emitted by UVA has a wavelength of 320-400nm, the ultraviolet light emitted by uvb has a wavelength of 275-320nm, the ultraviolet light emitted by uvc has a wavelength of 200-275nm, and the irradiation intensity is greater than 1.5mW/cm 2 。
7. The apparatus for removing surface stains from a semiconductor polishing pad as recited in claim 1, wherein the reaction chamber is made of glass, polypropylene or polytetrafluoroethylene, and an ultraviolet diffuse reflection layer is provided on an inner surface of the reaction chamber.
8. The apparatus for removing surface stains from a semiconductor polishing sheet according to claim 1, wherein in the rotating mechanism, a motor shaft of the driving motor is rigidly connected with a roller, rubber is applied to the surface of the roller, and friction contact is formed with the edge of the polishing sheet; the rotational speed of the motor shaft is controlled by a controller.
9. A method of eliminating surface mottle of a polishing sheet using the apparatus of any one of claims 1-8, comprising the steps of:
(1) The polishing sheets are placed in the flower basket clamping grooves, the polishing sheets in the flower basket are driven by the rolling shafts to do rotary motion, and the rotary speed of the polishing sheets is set to be at least one turn in the process time;
(2) Reaction chamber sealThen ozone circulation is started, and in the process, the irradiation intensity of ultraviolet light is kept to be more than 1.5mW/cm 2 ；
(3) The irradiation intensity wavelength component and the irradiation time of the ultraviolet array in the irradiation process are regulated according to the material and the doping type of the polished wafer, and the irradiation time is within 30s-10 min;
(4) After the irradiation is completed, the air valve is switched to the ozone absorption pipeline, and the circulation pumping time is at least one time according to the pumping capacity.
10. The method of claim 9, wherein the rotation mechanism rotates the polishing pad at a rotational speed of 1-60rpm.
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| JP2003133301A (en) * | 2001-10-26 | 2003-05-09 | Tokyo Electron Ltd | Device and method for forming oxide film for manufacturing semiconductor, and apparatus for ultraviolet irradiation |
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| CN103337450A (en) * | 2013-06-18 | 2013-10-02 | 上海交通大学 | Ultraviolet light/ozone surface cleaning and oxidation modification vacuum equipment and using method thereof |
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| CN108393302A (en) * | 2018-02-26 | 2018-08-14 | 上海提牛机电设备有限公司 | A kind of rotary Wafer Cleaning auxiliary device |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003133301A (en) * | 2001-10-26 | 2003-05-09 | Tokyo Electron Ltd | Device and method for forming oxide film for manufacturing semiconductor, and apparatus for ultraviolet irradiation |
| JP2007187814A (en) * | 2006-01-12 | 2007-07-26 | Canon Inc | Image forming apparatus |
| CN103337450A (en) * | 2013-06-18 | 2013-10-02 | 上海交通大学 | Ultraviolet light/ozone surface cleaning and oxidation modification vacuum equipment and using method thereof |
| CN207694610U (en) * | 2017-12-15 | 2018-08-07 | 江西博鑫精陶环保科技有限公司 | A kind of water treatment facilities of orientation selfreparing flat ceramic membrane module |
| CN108393302A (en) * | 2018-02-26 | 2018-08-14 | 上海提牛机电设备有限公司 | A kind of rotary Wafer Cleaning auxiliary device |
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