CN112536709A - Chemical mechanical polishing method and device - Google Patents
Chemical mechanical polishing method and device Download PDFInfo
- Publication number
- CN112536709A CN112536709A CN202011356583.3A CN202011356583A CN112536709A CN 112536709 A CN112536709 A CN 112536709A CN 202011356583 A CN202011356583 A CN 202011356583A CN 112536709 A CN112536709 A CN 112536709A
- Authority
- CN
- China
- Prior art keywords
- polishing
- cooling
- stage
- chemical mechanical
- liquid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000005498 polishing Methods 0.000 title claims abstract description 319
- 239000000126 substance Substances 0.000 title claims abstract description 43
- 238000000034 method Methods 0.000 title claims abstract description 23
- 238000001816 cooling Methods 0.000 claims abstract description 80
- 239000000110 cooling liquid Substances 0.000 claims abstract description 67
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 46
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 46
- 239000010703 silicon Substances 0.000 claims abstract description 46
- 239000000654 additive Substances 0.000 claims abstract description 16
- 230000000996 additive effect Effects 0.000 claims abstract description 16
- 239000007788 liquid Substances 0.000 claims description 53
- 239000004065 semiconductor Substances 0.000 abstract description 9
- 235000012431 wafers Nutrition 0.000 description 65
- 239000000243 solution Substances 0.000 description 46
- 239000002245 particle Substances 0.000 description 24
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 21
- 230000008859 change Effects 0.000 description 9
- 238000005260 corrosion Methods 0.000 description 8
- 230000007797 corrosion Effects 0.000 description 8
- 238000005054 agglomeration Methods 0.000 description 7
- 230000002776 aggregation Effects 0.000 description 7
- 238000007517 polishing process Methods 0.000 description 7
- 239000003513 alkali Substances 0.000 description 6
- 239000012670 alkaline solution Substances 0.000 description 6
- 239000007800 oxidant agent Substances 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 4
- 229910052681 coesite Inorganic materials 0.000 description 4
- 239000002826 coolant Substances 0.000 description 4
- 229910052906 cristobalite Inorganic materials 0.000 description 4
- 230000006866 deterioration Effects 0.000 description 4
- 239000000377 silicon dioxide Substances 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 229910052682 stishovite Inorganic materials 0.000 description 4
- 239000004094 surface-active agent Substances 0.000 description 4
- 229910052905 tridymite Inorganic materials 0.000 description 4
- 238000009825 accumulation Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000002105 nanoparticle Substances 0.000 description 3
- 230000002378 acidificating effect Effects 0.000 description 2
- 150000001412 amines Chemical class 0.000 description 2
- 230000001112 coagulating effect Effects 0.000 description 2
- 239000000084 colloidal system Substances 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 230000001050 lubricating effect Effects 0.000 description 2
- 229910021645 metal ion Inorganic materials 0.000 description 2
- 229910052755 nonmetal Inorganic materials 0.000 description 2
- 239000013618 particulate matter Substances 0.000 description 2
- 230000001376 precipitating effect Effects 0.000 description 2
- 238000006748 scratching Methods 0.000 description 2
- 230000002393 scratching effect Effects 0.000 description 2
- 239000003381 stabilizer Substances 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000002585 base Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 229910021642 ultra pure water Inorganic materials 0.000 description 1
- 239000012498 ultrapure water Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/04—Lapping machines or devices; Accessories designed for working plane surfaces
- B24B37/042—Lapping machines or devices; Accessories designed for working plane surfaces operating processes therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/005—Control means for lapping machines or devices
- B24B37/015—Temperature control
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/04—Lapping machines or devices; Accessories designed for working plane surfaces
- B24B37/07—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool
- B24B37/10—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool for single side lapping
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B55/00—Safety devices for grinding or polishing machines; Accessories fitted to grinding or polishing machines for keeping tools or parts of the machine in good working condition
- B24B55/02—Equipment for cooling the grinding surfaces, e.g. devices for feeding coolant
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
- H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
- H01L21/30625—With simultaneous mechanical treatment, e.g. mechanico-chemical polishing
Abstract
The invention provides a chemical mechanical polishing method and a chemical mechanical polishing device, and belongs to the technical field of semiconductors. The chemical mechanical polishing method comprises the following steps: carrying out chemical mechanical polishing on the silicon wafer by utilizing at least two polishing cooling stages, wherein each polishing cooling stage sequentially comprises a polishing stage and a cooling stage; polishing the silicon wafer by using a polishing solution in the polishing stage; and detecting the temperature of the polishing disk in the cooling stage, adjusting the additive amount of cooling liquid according to the temperature of the polishing disk, and directly introducing the cooling liquid to the surface of the polishing disk to cool the polishing disk. The invention can improve the surface flatness of the silicon wafer.
Description
Technical Field
The present invention relates to the field of semiconductor technology, and more particularly, to a chemical mechanical polishing method and apparatus.
Background
Single crystal silicon as a base material for semiconductor device production has very strict requirements on flatness, roughness, metal, particles, and the like of its surface, and in order to satisfy these requirements, it is required to be achieved by chemical mechanical polishing.
In the single crystal silicon wafer process flow, Chemical Mechanical Polishing (CMP) is a very important process, sometimes referred to as Chemical Mechanical planarization. So-called chemical mechanical polishing, generally, a single crystal silicon wafer is mounted on a wafer carrier and brought into contact with a polishing layer of a polishing pad, the polishing pad is rotated at a high speed, a polishing medium (e.g., slurry) is dispensed onto the polishing pad and sucked into a gap between the semiconductor wafer and the polishing layer, the semiconductor wafer is rubbed against the polishing pad by the pressure of a pressure device, and is ground to remove excess material, and finally, the ground surface of the semiconductor wafer is polished and a flat surface is obtained.
With the recent increase in higher performance and higher integration density and demand of semiconductor devices, there has been an increasing demand for improving productivity and surface quality in CMP of semiconductor wafers, wherein how to improve the flatness of the polished surface of the semiconductor wafer after final polishing is the focus of research in the current chemical mechanical polishing process.
Disclosure of Invention
The invention aims to provide a chemical mechanical polishing method and a chemical mechanical polishing device, which can improve the surface flatness of a silicon wafer.
To solve the above technical problem, embodiments of the present invention provide the following technical solutions:
in one aspect, an embodiment of the present invention provides a chemical mechanical polishing method, including:
carrying out chemical mechanical polishing on the silicon wafer by utilizing at least two polishing cooling stages, wherein each polishing cooling stage sequentially comprises a polishing stage and a cooling stage;
polishing the silicon wafer by using a polishing solution in the polishing stage; and detecting the temperature of the polishing disk in the cooling stage, adjusting the additive amount of cooling liquid according to the temperature of the polishing disk, and directly introducing the cooling liquid to the surface of the polishing disk to cool the polishing disk.
In some embodiments, the at least two polishing cooling stages include a first polishing cooling stage, and in the first polishing cooling stage, if the temperature of the polishing disk is less than or equal to 25 ℃, cooling liquid is introduced to the surface of the polishing disk at a flow rate of 1L/min, and the liquid supply time is 10-50 s.
In some embodiments, the at least two polishing cooling stages include a second polishing cooling stage, and in the second polishing cooling stage, if the temperature of the polishing disk is less than 26 ℃ and greater than 25 ℃, cooling liquid is introduced to the surface of the polishing disk at a flow rate of 1L/min, and the liquid supply time is 20-60 s.
In some embodiments, the at least two polishing cooling stages include a third polishing cooling stage, and in the third polishing cooling stage, if the temperature of the polishing disk is greater than 26 ℃, cooling liquid is introduced to the surface of the polishing disk at a flow rate of 1L/min, and the liquid supply time is 30-90 s.
In some embodiments, the same polishing liquid is used in the same polishing cooling stage, and the polishing liquid is different in different polishing cooling stages.
In some embodiments, the polishing time of the polishing stage is from 150s to 250 s.
On the other hand, the embodiment of the invention also provides a chemical mechanical polishing device, which utilizes at least two polishing cooling stages to carry out chemical mechanical polishing on a silicon wafer, wherein each polishing cooling stage sequentially comprises a polishing stage and a cooling stage; the apparatus includes a polishing unit and a cooling unit,
the polishing unit is used for polishing the silicon wafer by using polishing liquid in the polishing stage;
the cooling unit is used for detecting the temperature of the polishing disk in the cooling stage, adjusting the additive amount of cooling liquid according to the temperature of the polishing disk, and directly introducing the cooling liquid to the surface of the polishing disk to cool the polishing disk.
In some embodiments, the cooling unit is specifically configured to, if the temperature of the polishing disk is less than or equal to 25 ℃, introduce cooling liquid to the surface of the polishing disk at a flow rate of 1L/min for a liquid supply time of 10 to 50 s.
In some embodiments, the cooling unit is specifically configured to, if the temperature of the polishing pad is less than 26 ℃ and greater than 25 ℃, introduce the cooling liquid to the surface of the polishing pad at a flow rate of 1L/min for a liquid supply time of 20-60 s.
In some embodiments, the cooling unit is specifically configured to, if the temperature of the polishing disk is greater than 26 ℃, introduce cooling liquid to the surface of the polishing disk at a flow rate of 1L/min for a liquid supply time of 30-90 s.
The embodiment of the invention has the following beneficial effects:
in the scheme, considering that the temperature can influence the removal rate of chemical mechanical polishing and the flatness and the roughness of the monocrystalline silicon wafer in the polishing process, the additive amount of the cooling liquid is adjusted according to the temperature change of the processed polishing disk, so that the polishing disk can be effectively cooled; and the cooling liquid is directly introduced to the surface of the polishing disc, so that the polishing liquid on the surface of the polishing disc can be removed, the mixing of the polishing liquid in different polishing stages is avoided, the problem that the quality of the surface of the silicon wafer is poor or even scratched due to the agglomeration of abrasive particles caused by the mixing of the previous polishing liquid and the subsequently introduced polishing liquid is solved, the flatness and the roughness of the surface of the silicon wafer are improved, the accumulation of micro-nano particles on the surface of the silicon wafer is reduced, and the surface quality of the monocrystalline silicon wafer is improved.
Drawings
FIG. 1 is a schematic flow chart of a chemical mechanical polishing method according to an embodiment of the present invention;
FIGS. 2 and 3 are schematic diagrams illustrating the improvement of the quality of a single crystal silicon wafer according to an embodiment of the present invention.
Detailed Description
In order to make the technical problems, technical solutions and advantages to be solved by the embodiments of the present invention clearer, the following detailed description will be given with reference to the accompanying drawings and specific embodiments.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawings of the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the invention, are within the scope of the invention.
The temperature can influence the removal rate of chemical mechanical polishing and the flatness and the roughness of the monocrystalline silicon wafer in the polishing process, but the introduction amount of the cooling liquid in the prior art is fixed, so that the temperature of the polishing disk cannot be controlled according to the actual condition, and the quality of the monocrystalline silicon wafer is influenced.
The invention aims to provide a chemical mechanical polishing method and a chemical mechanical polishing device, which can improve the surface flatness of a silicon wafer.
The embodiment of the invention provides a chemical mechanical polishing method, which comprises the following steps:
carrying out chemical mechanical polishing on the silicon wafer by utilizing at least two polishing cooling stages, wherein each polishing cooling stage sequentially comprises a polishing stage and a cooling stage;
polishing the silicon wafer by using a polishing solution in the polishing stage; and detecting the temperature of the polishing disk in the cooling stage, adjusting the additive amount of cooling liquid according to the temperature of the polishing disk, and directly introducing the cooling liquid to the surface of the polishing disk to cool the polishing disk.
In this embodiment, considering that the temperature may affect the removal rate of the chemical mechanical polishing and the flatness and roughness of the single crystal silicon wafer during the polishing process, the amount of the additive of the coolant is adjusted according to the temperature change of the processed polishing disk, the polishing disk can be effectively cooled, and the temperature control is realized by the coolant, so that the flatness, roughness, and particulate matter level of the single crystal silicon wafer are improved.
In addition, in the prior art, different polishing liquids at different polishing stages are continuously and uninterruptedly supplied, for example, polishing liquid 2 is supplied immediately after the supply of polishing liquid 1 is finished, or, the polishing solution 2 is supplied in the process of supplying the polishing solution 1, and the mixing of different polishing solutions may cause the agglomeration of solid abrasive particles, which leads to the deterioration of the surface quality of the silicon wafer and even the scratch, and the cooling liquid is introduced into the polishing disk, while in the embodiment, after the polishing stage is finished, the cooling liquid is directly introduced into the surface of the polishing disk, can remove the polishing solution on the surface of the polishing disc, avoid the mixing of the polishing solutions in different polishing stages, prevent the surface quality of the silicon wafer from being deteriorated and even scratched caused by the agglomeration of abrasive particles due to the mixing of the prior polishing solution and the subsequently introduced polishing solution, therefore, the flatness and the roughness of the surface of the silicon wafer are improved, the accumulation of micro-nano particles on the surface of the silicon wafer is reduced, and the surface quality of the monocrystalline silicon wafer is improved.
In some embodiments, the at least two polishing cooling stages include a first polishing cooling stage, and in the first polishing cooling stage, if the temperature of the polishing disk is less than or equal to 25 ℃, cooling liquid is introduced to the surface of the polishing disk at a flow rate of 1L/min, and the liquid supply time is 10-50 s. The embodiment adjusts the additive amount of the cooling liquid according to the temperature change of the processed polishing disk, can effectively cool the polishing disk, and realizes temperature control through the cooling liquid, thereby improving the flatness, the roughness and the particle level of the monocrystalline silicon wafer.
In some embodiments, the at least two polishing cooling stages include a second polishing cooling stage, and in the second polishing cooling stage, if the temperature of the polishing disk is less than 26 ℃ and greater than 25 ℃, cooling liquid is introduced to the surface of the polishing disk at a flow rate of 1L/min, and the liquid supply time is 20-60 s. The additive amount of the cooling liquid is adjusted according to the temperature change of the processed polishing disk, the polishing disk can be effectively cooled, and the temperature control is realized through the cooling liquid, so that the flatness, the roughness and the particle level of the monocrystalline silicon wafer are improved.
In some embodiments, the at least two polishing cooling stages include a third polishing cooling stage, and in the third polishing cooling stage, if the temperature of the polishing disk is greater than 26 ℃, cooling liquid is introduced to the surface of the polishing disk at a flow rate of 1L/min, and the liquid supply time is 30-90 s. The additive amount of the cooling liquid is adjusted according to the temperature change of the processed polishing disk, the polishing disk can be effectively cooled, and the temperature control is realized through the cooling liquid, so that the flatness, the roughness and the particle level of the monocrystalline silicon wafer are improved.
In the prior art, different polishing solutions at different polishing stages are continuously supplied, for example, after the polishing solution 1 is supplied with liquid, the polishing solution 2 is immediately supplied, or the polishing solution 2 is supplied during the liquid supply process of the polishing solution 1, and the mixing of different polishing solutions may cause the agglomeration of solid abrasive particles, which leads to the deterioration of the surface quality of a silicon wafer and even the scratching of the silicon wafer.
In some embodiments, the polishing time of the polishing stage may be 150s to 250s, and when the above value is adopted in the polishing time, the silicon wafer can be effectively polished. Of course, the polishing time is not limited to the above value, and can be adjusted according to actual needs.
In an embodiment, taking chemical mechanical polishing of a silicon wafer by two polishing cooling stages as an example, as shown in fig. 1, the chemical mechanical polishing method of the embodiment includes the following steps:
firstly, in the first polishing cooling stage, the silicon wafer is polished by using the first polishing liquid, specifically, the monocrystalline silicon wafer can be processed by using a mixed liquid which is formed by uniformly mixing and stirring the first polishing liquid and ultrapure water (the mixing ratio can be 1: 15-1: 30), and the processing time can be 150s-250s (the same as the liquid supply time). When polishing, directly providing polishing solution to the surface of the silicon wafer, wherein the polishing solution is milky colloid with uniformly dispersed colloidal particles and mainly plays roles in polishing, lubricating and cooling. The polishing solution can be divided into acidic polishing solution and alkaline polishing solution according to acidity and alkalinity, and can be divided into metal polishing solution and nonmetal polishing solution according to application scenes. With basic SiO2Polishing liquid, for example, contains an abrasive (SiO) as an important component2Colloidal particles), alkali, deionized water, surfactants, oxidants, stabilizers, and the like. SiO 22The colloidal particles are mainly madeFor mechanical friction and adsorption of corrosion products, the size may be in the range of 1-100 nm. The alkaline solution mainly plays a role in corrosion in the polishing process, and the alkaline solution is usually organic amine due to the fact that metal ions such as Na +, K + and the like are prevented from being introduced, and the pH value of the alkaline solution is generally 9.4-11.1. The oxidizing agent is used to accelerate the corrosion reaction rate, since Si itself reacts slowly with alkali, while SiO2The reaction rate with alkali is fast, and the oxidizing agent can oxidize the surface Si, so that the fast corrosion speed is obtained. The surfactant is used for insoluble particles to prevent colloidal particles from coagulating and precipitating.
And after polishing is finished, measuring the temperature of the polishing disk at the moment, judging the temperature, adding the cooling liquid with the amount A when the temperature is higher than 1, and adding the cooling liquid with the amount B when the temperature is not higher than 1. In a specific example, when the temperature is lower than 25 ℃, cooling liquid is supplied to the polishing disc, the flow rate of the cooling liquid is 1L/min, and the liquid supply time is 10-50 s; in another specific example, when the temperature of the polishing disk is more than 25 ℃ and less than 26 ℃, cooling liquid is supplied to the polishing disk, the flow rate of the cooling liquid is 1L/min, and the liquid supply time is 20s-60 s; in another specific example, when the temperature of the polishing disk is more than 26 ℃, cooling liquid is supplied to the polishing disk, the flow rate of the cooling liquid is 1L/min, and the liquid supply time is 30s-90 s.
And then, a second polishing cooling stage is carried out, and in the second polishing cooling stage, the silicon wafer is polished by using second polishing liquid, wherein the second polishing liquid is different from the first polishing liquid.
And after polishing is finished, measuring the temperature of the polishing disk at the moment, judging the temperature, adding the cooling liquid with the amount C when the temperature is higher than the temperature 2, and adding the cooling liquid with the amount D when the temperature is not higher than the temperature 2. In a specific example, when the temperature is lower than 25 ℃, cooling liquid is supplied to the polishing disc, the flow rate of the cooling liquid is 1L/min, and the liquid supply time is 10-50 s; in another specific example, when the temperature of the polishing disk is more than 25 ℃ and less than 26 ℃, cooling liquid is supplied to the polishing disk, the flow rate of the cooling liquid is 1L/min, and the liquid supply time is 20s-60 s; in another specific example, when the temperature of the polishing disk is more than 26 ℃, cooling liquid is supplied to the polishing disk, the flow rate of the cooling liquid is 1L/min, and the liquid supply time is 30s-90 s.
The final optimization results are shown in fig. 2 and 3, where fig. 2 shows the Haze level of the silicon wafer polished by the prior art and the Haze level of the silicon wafer polished by this example, and it can be seen that the Haze level of the silicon wafer polished by this example is better than the Haze level of the silicon wafer polished by the prior art, where the unit for measuring the Haze level is nm.
Fig. 3 is a graph showing the roughness level of a silicon wafer polished by the prior art and the roughness level of a silicon wafer polished by this embodiment, and it can be seen that the roughness level of the silicon wafer polished by this embodiment is superior to the roughness level of the silicon wafer polished by the prior art, wherein the roughness level is measured in ppm.
The embodiment of the invention also provides a chemical mechanical polishing device, which utilizes at least two polishing cooling stages to carry out chemical mechanical polishing on a silicon wafer, wherein each polishing cooling stage sequentially comprises a polishing stage and a cooling stage; the apparatus includes a polishing unit and a cooling unit,
the polishing unit is used for polishing the silicon wafer by using polishing liquid in the polishing stage;
the cooling unit is used for detecting the temperature of the polishing disk in the cooling stage, adjusting the additive amount of cooling liquid according to the temperature of the polishing disk, and directly introducing the cooling liquid to the surface of the polishing disk to cool the polishing disk.
In this embodiment, considering that the temperature may affect the removal rate of the chemical mechanical polishing and the flatness and roughness of the single crystal silicon wafer during the polishing process, the amount of the additive of the coolant is adjusted according to the temperature change of the processed polishing disk, the polishing disk can be effectively cooled, and the temperature control is realized by the coolant, so that the flatness, roughness, and particulate matter level of the single crystal silicon wafer are improved.
In addition, in the prior art, different polishing liquids at different polishing stages are continuously and uninterruptedly supplied, for example, polishing liquid 2 is supplied immediately after the supply of polishing liquid 1 is finished, or, the polishing solution 2 is supplied in the process of supplying the polishing solution 1, and the mixing of different polishing solutions may cause the agglomeration of solid abrasive particles, which leads to the deterioration of the surface quality of the silicon wafer and even the scratch, and the cooling liquid is introduced into the polishing disk, while in the embodiment, after the polishing stage is finished, the cooling liquid is directly introduced into the surface of the polishing disk, can remove the polishing solution on the surface of the polishing disc, avoid the mixing of the polishing solutions in different polishing stages, prevent the surface quality of the silicon wafer from being deteriorated and even scratched caused by the agglomeration of abrasive particles due to the mixing of the prior polishing solution and the subsequently introduced polishing solution, therefore, the flatness and the roughness of the surface of the silicon wafer are improved, the accumulation of micro-nano particles on the surface of the silicon wafer is reduced, and the surface quality of the monocrystalline silicon wafer is improved.
In some embodiments, the cooling unit is specifically configured to, if the temperature of the polishing disk is less than or equal to 25 ℃, introduce cooling liquid to the surface of the polishing disk at a flow rate of 1L/min for a liquid supply time of 10 to 50 s. The embodiment adjusts the additive amount of the cooling liquid according to the temperature change of the processed polishing disk, can effectively cool the polishing disk, and realizes temperature control through the cooling liquid, thereby improving the flatness, the roughness and the particle level of the monocrystalline silicon wafer.
In some embodiments, the cooling unit is specifically configured to, if the temperature of the polishing pad is less than 26 ℃ and greater than 25 ℃, introduce the cooling liquid to the surface of the polishing pad at a flow rate of 1L/min for a liquid supply time of 20-60 s. The embodiment adjusts the additive amount of the cooling liquid according to the temperature change of the processed polishing disk, can effectively cool the polishing disk, and realizes temperature control through the cooling liquid, thereby improving the flatness, the roughness and the particle level of the monocrystalline silicon wafer.
In some embodiments, the cooling unit is specifically configured to, if the temperature of the polishing disk is greater than 26 ℃, introduce cooling liquid to the surface of the polishing disk at a flow rate of 1L/min for a liquid supply time of 30-90 s. The embodiment adjusts the additive amount of the cooling liquid according to the temperature change of the processed polishing disk, can effectively cool the polishing disk, and realizes temperature control through the cooling liquid, thereby improving the flatness, the roughness and the particle level of the monocrystalline silicon wafer.
In the prior art, different polishing solutions at different polishing stages are continuously supplied, for example, after the polishing solution 1 is supplied with liquid, the polishing solution 2 is immediately supplied, or the polishing solution 2 is supplied during the liquid supply process of the polishing solution 1, and the mixing of different polishing solutions may cause the agglomeration of solid abrasive particles, which leads to the deterioration of the surface quality of a silicon wafer and even the scratching of the silicon wafer.
In the embodiment, when polishing is performed, the polishing solution is directly provided to the surface of the silicon wafer, and the polishing solution is a milky colloid with uniformly dispersed colloidal particles, and mainly plays roles in polishing, lubricating and cooling. The polishing solution can be divided into acidic polishing solution and alkaline polishing solution according to acidity and alkalinity, and can be divided into metal polishing solution and nonmetal polishing solution according to application scenes. With basic SiO2Polishing liquid, for example, contains an abrasive (SiO) as an important component2Colloidal particles), alkali, deionized water, surfactants, oxidants, stabilizers, and the like. SiO 22The colloidal particles mainly function to perform mechanical friction and adsorb corrosion products, and can be 1-100nm in size. The alkaline solution mainly plays a role in corrosion in the polishing process, and the alkaline solution is usually organic amine due to the fact that metal ions such as Na +, K + and the like are prevented from being introduced, and the pH value of the alkaline solution is generally 9.4-11.1. The oxidizing agent is used to accelerate the corrosion reaction rate, since Si itself reacts slowly with alkali, while SiO2The reaction rate with alkali is fast, and the oxidizing agent can oxidize the surface Si, so that the fast corrosion speed is obtained. The surfactant is used for insoluble particles to prevent colloidal particles from coagulating and precipitating.
It should be noted that, in the present specification, all the embodiments are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the embodiments, since they are substantially similar to the product embodiments, the description is simple, and the relevant points can be referred to the partial description of the product embodiments.
Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.
It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element or intervening elements may be present.
In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.
The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present disclosure, and all the changes or substitutions should be covered within the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.
Claims (10)
1. A method of chemical mechanical polishing, comprising:
carrying out chemical mechanical polishing on the silicon wafer by utilizing at least two polishing cooling stages, wherein each polishing cooling stage sequentially comprises a polishing stage and a cooling stage;
polishing the silicon wafer by using a polishing solution in the polishing stage; and detecting the temperature of the polishing disk in the cooling stage, adjusting the additive amount of cooling liquid according to the temperature of the polishing disk, and directly introducing the cooling liquid to the surface of the polishing disk to cool the polishing disk.
2. The chemical mechanical polishing method of claim 1, wherein the at least two polishing cooling stages comprise a first polishing cooling stage, and in the first polishing cooling stage, if the temperature of the polishing pad is less than or equal to 25 ℃, cooling liquid is introduced to the surface of the polishing pad at a flow rate of 1L/min for a liquid supply time of 10-50 s.
3. The chemical mechanical polishing method of claim 1, wherein the at least two polishing cooling stages comprise a second polishing cooling stage, and in the second polishing cooling stage, if the temperature of the polishing disk is less than 26 ℃ and greater than 25 ℃, cooling liquid is introduced to the surface of the polishing disk at a flow rate of 1L/min for a liquid supply time of 20-60 s.
4. The chemical mechanical polishing method of claim 1, wherein the at least two polishing cooling stages comprise a third polishing cooling stage, and in the third polishing cooling stage, if the temperature of the polishing pad is higher than 26 ℃, cooling liquid is introduced to the surface of the polishing pad at a flow rate of 1L/min for a liquid supply time of 30-90 s.
5. The chemical mechanical polishing method of claim 1, wherein the same polishing liquid is used in the same polishing cooling stage, and the polishing liquids used in different polishing cooling stages are different.
6. The chemical mechanical polishing method of claim 1, wherein the polishing time of the polishing stage is 150s to 250 s.
7. A chemical mechanical polishing device is characterized in that a silicon wafer is subjected to chemical mechanical polishing by utilizing at least two polishing cooling stages, wherein each polishing cooling stage sequentially comprises a polishing stage and a cooling stage; the apparatus includes a polishing unit and a cooling unit,
the polishing unit is used for polishing the silicon wafer by using polishing liquid in the polishing stage;
the cooling unit is used for detecting the temperature of the polishing disk in the cooling stage, adjusting the additive amount of cooling liquid according to the temperature of the polishing disk, and directly introducing the cooling liquid to the surface of the polishing disk to cool the polishing disk.
8. The chemical mechanical polishing apparatus according to claim 7,
and the cooling unit is specifically used for introducing cooling liquid to the surface of the polishing disc at a flow rate of 1L/min for a liquid supply time of 10-50s if the temperature of the polishing disc is less than or equal to 25 ℃.
9. The chemical mechanical polishing apparatus according to claim 7,
and the cooling unit is specifically used for introducing cooling liquid to the surface of the polishing disc at a flow rate of 1L/min for a liquid supply time of 20-60s if the temperature of the polishing disc is less than 26 ℃ and greater than 25 ℃.
10. The chemical mechanical polishing apparatus according to claim 7,
and the cooling unit is specifically used for introducing cooling liquid to the surface of the polishing disc at a flow rate of 1L/min for 30-90s if the temperature of the polishing disc is higher than 26 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011356583.3A CN112536709A (en) | 2020-11-27 | 2020-11-27 | Chemical mechanical polishing method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011356583.3A CN112536709A (en) | 2020-11-27 | 2020-11-27 | Chemical mechanical polishing method and device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112536709A true CN112536709A (en) | 2021-03-23 |
Family
ID=75016944
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011356583.3A Pending CN112536709A (en) | 2020-11-27 | 2020-11-27 | Chemical mechanical polishing method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112536709A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202491166U (en) * | 2012-02-03 | 2012-10-17 | 中芯国际集成电路制造(上海)有限公司 | Grinding head and grinding device capable of enhancing wafer grinding uniformity |
| CN106312696A (en) * | 2016-09-14 | 2017-01-11 | 天津华海清科机电科技有限公司 | Chemico-mechanical polishing method and device |
| CN111318955A (en) * | 2018-12-13 | 2020-06-23 | 夏泰鑫半导体(青岛)有限公司 | Chemical mechanical polishing apparatus and method for performing cerium oxide-based chemical mechanical polishing |
-
2020
- 2020-11-27 CN CN202011356583.3A patent/CN112536709A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202491166U (en) * | 2012-02-03 | 2012-10-17 | 中芯国际集成电路制造(上海)有限公司 | Grinding head and grinding device capable of enhancing wafer grinding uniformity |
| CN106312696A (en) * | 2016-09-14 | 2017-01-11 | 天津华海清科机电科技有限公司 | Chemico-mechanical polishing method and device |
| CN111318955A (en) * | 2018-12-13 | 2020-06-23 | 夏泰鑫半导体(青岛)有限公司 | Chemical mechanical polishing apparatus and method for performing cerium oxide-based chemical mechanical polishing |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100491074C (en) | Method for controlling roughness of silicon crystal substrate material surface | |
| US6451696B1 (en) | Method for reclaiming wafer substrate and polishing solution compositions therefor | |
| WO2013035539A1 (en) | Polishing agent and polishing method | |
| CN111251163B (en) | Processing method for polished silicon wafer with hydrophilic surface | |
| US8058173B2 (en) | Methods for producing smooth wafers | |
| KR101390307B1 (en) | Method for producing epitaxial silicon wafer | |
| US20190115205A1 (en) | Silicon carbide wafer and method for production thereof | |
| CN108250977A (en) | A kind of chemical mechanical polishing liquid for barrier layer planarization | |
| US20080182413A1 (en) | Selective chemistry for fixed abrasive cmp | |
| JP2004165424A (en) | Polishing agent composition and polishing method using the same | |
| CN112536709A (en) | Chemical mechanical polishing method and device | |
| JP2004146780A (en) | Polishing liquid composition | |
| WO2019207926A1 (en) | Polishing agent for synthetic quartz glass substrates, method for producing same, and method for polishing synthetic quartz glass substrate | |
| JP2001200243A (en) | Abrasive material, production method thereof, and polishing method using asme | |
| CN113579991B (en) | Final polishing method and system for silicon wafer and silicon wafer | |
| Nair et al. | Chemical mechanical planarization of germanium using oxone® based silica slurries | |
| Zhang et al. | CMP challenges for advanced technology nodes | |
| US8211325B2 (en) | Process sequence to achieve global planarity using a combination of fixed abrasive and high selectivity slurry for pre-metal dielectric CMP applications | |
| CN108250972B (en) | Chemical mechanical polishing solution for barrier layer planarization | |
| US7857986B2 (en) | Chemical mechanical polishing slurry and chemical mechanical polishing apparatus and method | |
| KR102492236B1 (en) | Polishing device and method of polishing for wafer | |
| CN111378366A (en) | Chemical mechanical polishing solution and application thereof | |
| TWI779129B (en) | Abrasive for synthetic quartz glass substrate and grinding method for synthetic quartz glass substrate | |
| CN114774003B (en) | NiP modified layer chemical mechanical polishing solution and preparation method and application thereof | |
| KR20050073044A (en) | Chemical mechanical polishing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20220628 Address after: 710000 room 1-3-029, No. 1888, Xifeng South Road, high tech Zone, Xi'an, Shaanxi Province Applicant after: Xi'an yisiwei Material Technology Co.,Ltd. Applicant after: XI'AN ESWIN SILICON WAFER TECHNOLOGY Co.,Ltd. Address before: Room 1323, block a, city gate, No.1 Jinye Road, high tech Zone, Xi'an, Shaanxi 710065 Applicant before: XI'AN ESWIN SILICON WAFER TECHNOLOGY Co.,Ltd. Applicant before: Xi'an yisiwei Material Technology Co.,Ltd. |
|
| TA01 | Transfer of patent application right | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210323 |
|
| RJ01 | Rejection of invention patent application after publication |