CN115820127A - Chemical mechanical polishing solution suitable for copper-cobalt interconnection structure and preparation method thereof - Google Patents
Chemical mechanical polishing solution suitable for copper-cobalt interconnection structure and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a chemical mechanical polishing solution suitable for a copper-cobalt interconnection structure and a preparation method thereof, wherein the polishing solution comprises, by mass, 0.1-10% of grinding particles, 0.01-3% of an oxidizing agent, 0.1-5% of a complexing agent, 0.01-1.0% of an inhibitor and the balance of deionized water; wherein the inhibitor is abietic acid and its salt, preferably disproportionated abietic acid and its salt, and is effective in inhibiting static corrosion of copper and cobalt, and the pH of the polishing solution is 8-11. The polishing solution is added with the inhibitor of the abietic acid and the salt thereof, so that the crystalline corrosion of copper can be inhibited while the higher polishing rate of the copper is kept, and the surface quality after polishing is effectively improved. Meanwhile, the polishing solution has extremely low static corrosion and removal rate to cobalt, and can meet the requirement of high selectivity ratio in the first-step polishing process of the interconnection structure.
Description
Technical Field
The invention belongs to the technical field of microelectronic processes, and particularly relates to a chemical mechanical polishing solution suitable for a copper-cobalt interconnection structure and a preparation method thereof.
Background
Electronization is an important sign in the information age, and chips are the foundation of the electronic information industry. The characteristic dimension of the integrated circuit is rapidly developed from submicron level at the beginning of century to the current nanometer level, so that the performance of the chip is more excellent and the power consumption is lower. Today, hundreds of millions of transistors can be accommodated on a chip substrate per square millimeter, and these transistors are often connected by copper interconnects. The copper interconnect structure includes a copper interconnect layer and a common tantalum/tantalum nitride barrier layer that prevents diffusion of copper atoms into the dielectric layer to avoid shorting and failure of the device. However, at the feature size of nanometer level, the tantalum/tantalum nitride structure which is difficult to be thinned restricts the further miniaturization of the transistor and the interconnecting line on one hand, and also starts to dominate the resistivity of the whole interconnecting structure on the other hand, causing the RC delay of the circuit. Therefore, in the chip manufacturing process, new materials and new processes are urgently needed to meet the requirements of higher performance and functions.
Metallic cobalt as a barrier layer has been introduced as a solution into the structure of advanced chips by some chip manufacturers who have mastered sophisticated fabrication techniques. Research shows that cobalt as a barrier layer can meet the requirement of thinner barrier layer, simplify the deposition process, directly perform copper electroplating without depositing copper seed crystals, and have more excellent electroplating gap-filling property. In addition, cobalt has the advantages of lower resistivity, better adhesion to copper, and the like, compared to tantalum. However, chip fabrication is a complicated multi-flow process, and the implementation of copper/cobalt interconnect structures, despite the above advantages, presents a difficult problem for the subsequent Chemical Mechanical Planarization (CMP) process: the existing mature copper interconnection CMP technology is only suitable for copper/tantalum nitride structures, especially for commercial CMP polishing solution, and is not suitable for cobalt with larger difference with physical and chemical properties of copper and tantalum. And cobalt is commonly used in chip structures below ten nanometers, and the size has more strict and higher-precision requirements on CMP.
The flatness of the polished surface is both related to the requirements of the chip structure itself and affects the focusing precision in the subsequent photolithography process. Therefore, with the background of the miniaturization and multilayering of chip structures, CMP has become a key technology in chip manufacturing, and directly affects the manufacturing yield and final performance of chips. The CMP technique has the advantage of combining the physical friction of the nanoparticles in the polishing slurry (slurry) with the chemical action of other additive components. Not only is the efficient removal of the excess material on the surface of the interconnection layer achieved, but also the nano-to atomic-level roughness of the polished surface is maintained. Compared with copper and tantalum, cobalt is more active in chemical property, common commercial acidic polishing solution has a violent corrosion effect on cobalt, and excessive corrosion easily causes the defect of a barrier layer. Furthermore, the polishing rate of cobalt may even exceed that of copper itself, and the requirement of high selectivity in the first step of CMP cannot be met, i.e., the removal rate of copper in the interconnect metal should be much greater than that of cobalt in the barrier layer. In contrast, an excessively low etch rate typically significantly reduces the interconnect metal removal rate, affecting polishing efficiency.
CN102304327 uses a polishing solution containing thiazole inhibitor for planarization of copper/cobalt heterostructure. However, the static corrosion rate of the acidic polishing solution to cobalt is as low as 20nm/min, and considering that the thickness of the cobalt barrier layer is generally less than 5 nm, the cobalt barrier layer is easy to cause excessive dissolution and loss of the side wall barrier layer and even desorption of the whole barrier layer.
Disclosure of Invention
Based on the problems of the prior art, the invention provides a chemical mechanical polishing solution suitable for a copper-cobalt interconnection structure and a preparation method thereof, so as to meet the requirements of a chip on high selectivity, low defect and high-quality surface of the copper-cobalt interconnection structure in the chemical mechanical polishing process. The polishing solution is added with the inhibitor of the abietic acid and the salt thereof, so that the crystalline corrosion of copper can be inhibited while the higher polishing rate of the copper is kept, and the surface quality after polishing is effectively improved. Meanwhile, the polishing solution has extremely low static corrosion and removal rate to cobalt, and can meet the requirement of high selectivity ratio in the first-step polishing process of the interconnection structure.
In order to realize the purpose, the technical scheme of the invention is as follows:
the chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure comprises, by mass, 0.1-10% of abrasive particles, 0.01-3% of an oxidizing agent, 0.1-5% of a complexing agent, 0.01-1.0% of an inhibitor and the balance of deionized water;
wherein the inhibitor is abietic acid and salt thereof, preferably disproportionated abietic acid and salt thereof, more preferably disproportionated rosin potassium solution, and is effective in inhibiting static corrosion of copper and cobalt, and the pH of the polishing solution is 8-11.
Preferably, the polishing solution further comprises a pH regulator for regulating the pH of the polishing solution to 8-11. The pH regulator can be any one of nitric acid solution, potassium hydroxide solution and organic alkali hydroxylamine or a mixture of the nitric acid solution, the potassium hydroxide solution and the organic alkali hydroxylamine.
The grinding particles are used for removing metal or metal reactant contacted with the grinding particles through mechanical friction, so that the aim of mechanical removal is fulfilled. The abrasive particles can be selected from silicon dioxide, cerium dioxide or aluminum oxide particles, wherein silicon dioxide sol is preferred as the abrasive particles. The particle size of the abrasive particles is preferably 20 to 200nm.
The oxidizing agent functions to oxidize the copper metal, the cobalt barrier metal, to the corresponding metal oxide, hydroxide or ion. Preferably, the oxidizing agent is hydrogen peroxide.
The complexing agent is used for forming a chelate with the polishing surface and metal ions in the polishing solution, and is helpful for reducing metal particles in the polishing solution and metal ion pollution on the surface of the polished metal. Preferably, the complexing agent is an amino acid. The amino acid is selected from glycine, arginine, lysine, alanine, leucine, valine, histidine, cysteine, serine, and proline.
Based on the same inventive concept, the invention also provides a preparation method of the chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure, which comprises the following steps:
adding a complexing agent into deionized water according to a mass ratio to mix into a solution, then adjusting the pH value of the solution to 8-11, then adding abrasive particles and an inhibitor to mix, and adding an oxidant into the solution before use to obtain the chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure.
Due to the adoption of the technical scheme, compared with the prior art, the invention has the following advantages and positive effects:
in an integrated circuit, co is used as a barrier layer of a copper interconnection layer, the Co barrier layer and the copper interconnection layer jointly form a copper interconnection structure, and abietic acid is used as an inhibitor for CMP of the copper interconnection structure. Among the components of the CMP polishing solution, the inhibitor plays a decisive role in the surface quality after polishing, and is the most important component in the polishing solution. The copper interconnection structure prepared by the Damascus process has uneven surface due to the groove formed by photoetching and a patterning structure required by the process. The inhibitor is adsorbed on the metal surface, so that the static corrosion of the metal surface is reduced, the over-polishing of materials in the groove can be effectively avoided, the planarization efficiency is improved, and the surface quality after polishing is determined. Compared with the common inhibitors such as triazole and thiazole in the field, the abietic acid is a substance of biological origin and is a green inhibitor. Because the rosin acid contains conjugated unsaturated double bonds, the disproportionated rosin acid which is a common product in industry is a cheap industrial raw material. Therefore, the disproportionated rosin acid is used as an inhibitor, and is relatively environment-friendly compared with the existing inhibitor.
By adopting the CMP polishing solution, the copper-cobalt interconnection structure has extremely low static corrosion effect on copper and cobalt in the process of chemical mechanical grinding, reduces the defect after polishing, and is beneficial to improving the planarization uniformity and the surface quality after polishing; meanwhile, the method can realize higher copper removal rate and extremely low cobalt polishing rate, realize high selectivity of copper/cobalt removal rate, and ensure that the selectivity ratio of the removal rate of the copper/cobalt material is within 21.1-50.3.
Drawings
FIG. 1 is a scanning electron microscope image of the surface topography of a copper wafer untreated with a polishing solution in an embodiment of the present invention;
FIG. 2 is an atomic force microscope image of the surface topography of a copper wafer untreated with a polishing solution in an embodiment of the present invention;
FIG. 3 is a scanning electron microscope image of the surface topography of a copper wafer statically etched by DR-0 polishing solution in an embodiment of the present invention;
FIG. 4 is an AFM image of the surface topography of a copper wafer after static erosion by a DR-0 slurry in accordance with an embodiment of the present invention;
FIG. 5 is a scanning electron microscope image of the surface topography of a copper wafer statically etched by the DR-2 polishing solution in an embodiment of the present invention;
FIG. 6 is an atomic force microscope image of the surface topography of a copper wafer after static erosion by the DR-2 slurry in accordance with an embodiment of the present invention.
Detailed Description
The chemical mechanical polishing solution suitable for copper-cobalt interconnection structures and the preparation method thereof proposed by the present invention are further described in detail with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description.
1. The mass of each component was calculated from the ratio of each component in table 1. Adding glycine into deionized water, stirring to completely dissolve the glycine, and leaving a small amount of residual water in the deionized water for subsequent pH adjustment; adjusting the pH to the specified value using 5% or 45% aqueous potassium hydroxide; subsequently, silica sol having a particle size of 80 nm and an aqueous solution of disproportionated potassium rosinate were added, and hydrogen peroxide was finally added at the time of use or the day before.
Table 1: slurry composition
| Slurry material | Hydrogen peroxide/wt% | Glycine per wt% | pH | Silica sol/wt% | Disproportionated potassium rosinate/wt% |
| DR-0 | 0.4 | 1.0 | 9.5 | 0.0 | 0.0 |
| DR-1 | 0.4 | 1.0 | 9.5 | 0.0 | 0.2 |
| DR-2 | 0.4 | 1.0 | 9.5 | 0.0 | 0.3 |
| DR-3 | 0.4 | 1.0 | 9.5 | 0.0 | 0.4 |
| DR-4 | 0.4 | 1.0 | 9.5 | 0.0 | 0.5 |
| RR-0 | 0.4 | 1.0 | 9.5 | 3.0 | 0.0 |
| RR-1 | 0.4 | 1.0 | 9.5 | 3.0 | 0.2 |
| RR-2 | 0.4 | 1.0 | 9.5 | 3.0 | 0.3 |
| RR-3 | 0.4 | 1.0 | 9.5 | 3.0 | 0.4 |
| RR-4 | 0.4 | 1.0 | 9.5 | 3.0 | 0.5 |
| RR-5 | 0.5 | 1.0 | 9.5 | 3.0 | 0.0 |
| RR-6 | 0.5 | 1.0 | 9.5 | 3.0 | 0.3 |
| RR-7 | 1.0 | 1.0 | 9.5 | 3.0 | 0.0 |
| RR-8 | 1.0 | 1.0 | 9.5 | 3.0 | 0.3 |
| RR-9 | 0.4 | 1.0 | 10.0 | 0.5 | 0.3 |
| RR-10 | 0.4 | 1.0 | 10.0 | 0.5 | 0.4 |
In the above examples, the DR series was used as a static corrosion test, and in order to avoid measurement errors, no silica sol was added, and the RR series was used as a polishing test. Where DR-0 and RR-0 are exemplified without disproportionated potassium rosinate, a comparative example is provided.
2. Static etching
The static etch simulates the behavior of patterned wafer designs or process-formed dimples during dynamic polishing. And respectively placing the two-inch copper wafer and the cobalt wafer into 200 ml of the following slurry, standing for 5 minutes, taking out, cleaning with deionized water, blow-drying with nitrogen, and calculating the static corrosion rate. The static corrosion rate is calculated by a weight loss method, namely the product of the mass difference before and after corrosion divided by the area, density and time of the workpiece.
Table 2: static corrosion rate of copper and cobalt (unit: nanometer/minute)
| Slurry material | DR-0 | DR-1 | DR-2 | DR-3 | DR-4 |
| Static corrosion rate of copper | 82.2 | 24.1 | 0.7 | 0.0 | 0.0 |
| Static corrosion rate of cobalt | 0.8 | 0.0 | 0.0 | 0.0 | 0.0 |
DR-0 is a comparative example without disproportionated potassium rosinate. As can be seen from table 2, after the disproportionated potassium abietate is introduced, the static corrosion rates of copper and cobalt are both greatly reduced, which indicates that the disproportionated potassium abietate has a significant inhibition effect on the static corrosion of copper and cobalt. Because the wafer valleys do not contact the polishing pad, no rubbing action occurs, and only chemical corrosion exists, the static corrosion experiment simulates the state of the valleys formed by the patterned wafer design or process during the dynamic polishing process. The low static etch rate means that CMP can only remove material at the bumps, which will facilitate an increase in planarization efficiency. On the other hand, the defects of an interconnection layer and a barrier layer caused by further corrosion of the interconnection line with the internal planarization by the polishing solution after polishing can be avoided.
In an actual CMP process, polishing typically lasts for about one minute. Taking copper as an example, two inch copper wafers were left standing in slurries DR-0 and DR-2 for one minute, taken out and washed with deionized water, blown dry with nitrogen, placed under an electron microscope for observation of surface morphology, and measured for surface roughness using an atomic force microscope, as shown in fig. 1-6 and results in table 3, corresponding to the untreated samples and their samples after etching in DR-0 and DR-2. It can be seen that in the DR-0 slurry without disproportionated potassium rosinate, a more severe corrosion of the copper surface occurred. Whereas in DR-2 containing 0.3% potassium disproportionated rosin, there was little difference between the copper surface and the untreated surface, further demonstrating the excellent corrosion inhibition effect of potassium disproportionated rosin.
TABLE 3 roughness of copper wafer surface
| Sample (I) | Blank control | DR-0 | DR-2 |
| Average roughness/nm | 1.712 | 10.162 | 1.817 |
| Root mean square roughness/nm | 2.132 | 12.781 | 1.450 |
3. Chemical mechanical polishing
CMP experiments were performed using a two-inch workpiece and polishing rates and selectivity ratios were calculated. The equipment used is a chemical mechanical polishing machine of Corjing UNIPOL-1203, which has a rotary table and a peristaltic pump. The polishing pad used was IC1010/SUBA IV with concentric circular grooves. The experiments were performed at room temperature, typically 15-30 degrees celsius.
During polishing, a workpiece is adsorbed on the surface of a polishing head and pressed on a rotary table attached with a polishing pad, polishing liquid is conveyed between the workpiece and the polishing pad through a peristaltic pump, and the polishing head and the rotary table rotate simultaneously to achieve the purposes of removing redundant materials on the surface of the workpiece and flattening.
The process conditions are as follows: the platen was rotated at 150 rpm, the slurry feed rate was 100 ml/min, and the head pressure was 1.6 psi. Polishing for two minutes, cleaning with deionized water after finishing polishing, and drying with nitrogen. The polishing rate and the static etch rate were calculated in the same manner, and the selection ratio, i.e., the ratio of the copper and cobalt removal rates, was selected and the results are shown in Table 4 below.
It can be seen from table 4 that the addition of disproportionated potassium rosinate also has a certain inhibitory effect on the copper dynamic CMP process, which significantly reduces the material removal rate. Overall, the slurry composition can maintain a high dynamic copper removal rate while maintaining low static corrosion of copper. At the same time, the removal rate of cobalt is maintained at a very low level compared to copper under the combined action of the slurry composition, thereby achieving high selectivity removal of the copper/cobalt heterostructure.
The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, it is still within the scope of the present invention if they fall within the scope of the claims of the present invention and their equivalents.
Claims (10)
1. The chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure is characterized by comprising 0.1-10% of grinding particles, 0.01-3% of an oxidizing agent, 0.1-5% of a complexing agent, 0.01-1.0% of an inhibitor and the balance of deionized water in percentage by mass;
wherein the inhibitor is abietic acid and salt thereof, and the pH value of the polishing solution is 8-11.
2. The chemical mechanical polishing solution suitable for copper-cobalt interconnection structures as claimed in claim 1, wherein the inhibitor is disproportionated abietic acid and a salt thereof.
3. The chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure as claimed in claim 1 or 2, wherein the polishing solution further comprises a pH adjusting agent for adjusting the pH of the polishing solution to 8-11.
4. The chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure of claim 3, wherein the pH regulator is any one of nitric acid solution, potassium hydroxide solution, organic base hydroxylamine or a mixture thereof.
5. The chemical mechanical polishing solution suitable for copper-cobalt interconnection structure of claim 1, wherein the abrasive particles are silicon dioxide, cerium dioxide or aluminum trioxide.
6. The chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure of claim 5, wherein the abrasive particles have a particle size of 20-200nm.
7. The chemical mechanical polishing solution suitable for copper-cobalt interconnection structure of claim 1, wherein the oxidizing agent is hydrogen peroxide.
8. The chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure as claimed in claim 1, wherein the complexing agent is an amino acid.
9. The chemical mechanical polishing solution suitable for copper-cobalt interconnection structures of claim 8, wherein the amino acid is selected from glycine, arginine, lysine, alanine, leucine, valine, histidine, cysteine, serine, and proline.
10. A method for preparing a chemical mechanical polishing solution suitable for a copper-cobalt interconnection structure according to any one of claims 1 to 9, comprising the following steps:
adding a complexing agent into deionized water according to a mass ratio to mix into a solution, then adjusting the pH value of the solution to 8-11, then adding abrasive particles and an inhibitor to mix, and adding an oxidant into the solution before use to obtain the chemical mechanical polishing solution suitable for the copper-cobalt interconnection structure.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6440856B1 (en) * | 1999-09-14 | 2002-08-27 | Jsr Corporation | Cleaning agent for semiconductor parts and method for cleaning semiconductor parts |
| CN101689493A (en) * | 2007-06-20 | 2010-03-31 | 旭硝子株式会社 | Polishing composition and method for manufacturing semiconductor integrated circuit device |
| CN102210013A (en) * | 2008-11-10 | 2011-10-05 | 旭硝子株式会社 | Abrasive composition and method for manufacturing semiconductor integrated circuit device |
| CN102304327A (en) * | 2011-07-05 | 2012-01-04 | 复旦大学 | Polishing solution based on metal Co for polishing process |
| CN109972145A (en) * | 2017-12-27 | 2019-07-05 | 安集微电子（上海）有限公司 | A kind of chemical mechanical polishing liquid |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6440856B1 (en) * | 1999-09-14 | 2002-08-27 | Jsr Corporation | Cleaning agent for semiconductor parts and method for cleaning semiconductor parts |
| CN101689493A (en) * | 2007-06-20 | 2010-03-31 | 旭硝子株式会社 | Polishing composition and method for manufacturing semiconductor integrated circuit device |
| CN102210013A (en) * | 2008-11-10 | 2011-10-05 | 旭硝子株式会社 | Abrasive composition and method for manufacturing semiconductor integrated circuit device |
| CN102304327A (en) * | 2011-07-05 | 2012-01-04 | 复旦大学 | Polishing solution based on metal Co for polishing process |
| CN109972145A (en) * | 2017-12-27 | 2019-07-05 | 安集微电子（上海）有限公司 | A kind of chemical mechanical polishing liquid |
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