Research on Effects of Slurry Additives in Cu CMP for ULSI Manufacturing

2006 ◽  
Vol 304-305 ◽  
pp. 350-354 ◽  
Author(s):  
X.J. Li ◽  
Dong Ming Guo ◽  
R.K. Ren ◽  
Zhu Ji Jin
Keyword(s):  
Hydrogen Peroxide ◽  
Surface Roughness ◽  
Electrochemical Impedance Spectroscopy ◽  
Citric Acid ◽  
Chemical Mechanical Polishing ◽  
Electrochemical Impedance ◽  
Etching Rate ◽  
Complexing Agent ◽  
Cu Cmp ◽  
Static Etching

In this paper, in order to analyze the oxidation, dissolution and corrosive inhibition effects of additives in the slurry for copper Chemical-mechanical polishing(CMP), the slurry(pH5) with the peroxide as an oxidant, the citric acid as a complexing agent and the benzotriazole(BTA) as an inhibitor is studied. The static etching rate and polishing rate of the Cu-H2O2-Citric acid-BTA slurry are measured. The electrochemical behavior involved in the dissolution and corrosive inhibition of copper in the solutions containing additives is investigated by the electrochemical impedance spectroscopy (EIS) studies. The surface roughness is measured using ZYGO 3-D surface profiler. It is observed that when the slurry is with only 5wt% peroxide existing, copper is stable and slight etching rate on the copper is produced, and the etching rate is only 8.7nm/min. When 0.6wt% citric acid presents after adding 5wt% hydrogen peroxide, the etching rate will increase by 5.3 times, with a blue complexing product emerging. When the inhibitor BTA is added, the corrosion will be effectively restrained. From the EIS results, the impedance of copper in 5wt% peroxide solution which is in passivation can be greatly decreased by adding the citric acid as a complexing reagent. And the impedance of copper in the solution containing peroxide and citric acid can be increased by the addition of BTA. The surface roughness of the wafer polished with the slurry of 5wt% peroxide+0.6wt% citric acid+0.12wt% BTA slurry is Ra 4.7 Å.

Chemical Mechanical Polishing of Cu Pattern Wafer Based Alkaline Slurry in GLSI with R(NH2)n as Complexing Agent

2011 ◽  
Vol 236-238 ◽  
pp. 3020-3023 ◽  
Author(s):  
Yan Gang He ◽  
Xiao Wei Gan ◽  
Wei Hong ◽  
Yi Hu ◽  
Yu Ling Liu
Keyword(s):  
Reaction Mechanism ◽  
Chemical Mechanical Polishing ◽  
Mechanical Polishing ◽  
Complexing Agents ◽  
Complexing Agent ◽  
Mechanism Analysis ◽  
Slurry Stability ◽  
Cu Cmp ◽  
Better Than

Chemical mechanical polishing (CMP) of Cu pattern wafer based alkaline slurry in GLSI with R(NH2)n as complexing agent was investigated. In Cu CMP procedure, it is necessary to minimize the surface dishing and erosion while maintaining good planarity. This requirements are met through the complexing agents. Based on the reaction mechanism analysis of Cu in alkaline slurry with R(NH2)n as complexing agent in CMP, the performance of Cu dishing and erosion were discussed. The results showed that the slurry stability can be improved obviously by the addition of R(NH2)n as complexing agent, both Cu1 and Cu2 have good dishing and erosion performance. Furthermore, the dishing condition of Cu2 (180-230nm) is better than that of Cu1 (280-370nm), and the erosion condition of Cu2 (230-260nm) is also better than that of Cu1 (450-500nm).

Effect of complexing agents on desulphurization and deashing of coal by H2O2/H2SO4 leaching

2018 ◽  
Vol 29 (7) ◽  
pp. 1142-1154
Author(s):  
Hafiza Sana ◽  
Rizwan Haider ◽  
Muhammad Usman Rahim ◽  
Shahid Munir
Keyword(s):  
Hydrogen Peroxide ◽  
Citric Acid ◽  
Phosphoric Acid ◽  
Removal Efficiency ◽  
Coal Sample ◽  
Complexing Agents ◽  
Complexing Agent ◽  
Chemical Leaching ◽  
Optimized Conditions

The present study was aimed at investigating the effect of the addition of complexing agents on the removal efficiency of sulphur and ash contents during chemical leaching by acidified hydrogen peroxide. Representative coal sample from Lakhra was subjected to chemical leaching under various conditions of the parameters including time (60 and 120 min), temperature (25 and 50°C), complexing agents (citric acid and phosphoric acid) and the concentration of complexing agents (100 and 1000 ppm). The addition of complexing agents, i.e. citric acid and phosphoric acid imparted significant effects on improving the removal efficiency of sulphur and ash contents. Under optimized conditions, it was found out that the addition of citric acid improved the removal efficiency for sulphur from 63.88 to 83.47% and from 33.12 to 66.25% for ash. In case of phosphoric acid, the removal in sulphur and ash contents was increased from 63.77 to 80.77% and from 33.12 to 59.18%, respectively. Apparently, citric acid happened to be the most effective complexing agent, as compared to phosphoric acid. These results warrant subsequent detailed studies for further optimization of the process, including the use of some other complexing agents, as well.

scholarly journals Urea as a complexing agent for selective removal of Ta and Cu in sodium carbonate based alumina CMP slurry

2021 ◽  
pp. 49-49
Author(s):  
Arpita Shukla ◽  
Victoria Selvam ◽  
Manivannan Ramachandran
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Sodium Carbonate ◽  
Corrosion Potential ◽  
Electrochemical Impedance ◽  
Removal Rate ◽  
Chemical Mechanical Planarization ◽  
Corrosion Current ◽  
Complexing Agent ◽  
Downward Pressure

This work reports urea as a promising complexing agent in sodium carbonate (Na2CO3) based alumina slurry for chemical mechanical planarization (CMP) of tantalum (Ta) and copper (Cu). Ta and Cu were polished using Na2CO3 (1 wt.%) with alumina (2 wt.%) in the presence and absence of urea. The effect of slurry pH, urea concentration, applied downward pressure and platen rotational speed were deliberated and the outcomes were conveyed. Prior to the addition of urea, Ta removal rate (RR) was observed to enhance with pH from acidic to alkaline having maximum RR at pH 11. However, Cu RR decreases with increasing pH with minimum RR at pH 11. With the addition of urea in the slurry, Cu to Ta removal rate selectivity of nearly 1:1 is encountered at pH 11. The addition of urea boosts the Ta RR and suppresses Cu RR at the same time at 11 pH, as it adsorbs on the metal surface. Potentiodynamic polarization was conducted to determine the corrosion current (Icorr) and the corrosion potential (Ecorr). The electrochemical impedance spectroscopy (EIS) of both the metals was carried out in the proposed formulation and the obtained outcomes were elaborated.

Chemical-Mechanical Planarization of Copper: The Effect of Inhibitor and Complexing Agent

2003 ◽  
Vol 767 ◽  
Author(s):  
Ying Luo ◽  
Tianbao Du ◽  
Vimal Desai
Keyword(s):  
Hydrogen Peroxide ◽  
Photoelectron Spectroscopy ◽  
Removal Rate ◽  
Chemical Mechanical Planarization ◽  
Electrochemical Process ◽  
Copper Removal ◽  
Alkaline Condition ◽  
Complexing Agent ◽  
Polarization Studies ◽  
Cu Cmp

AbstractThe present investigation was focused on understanding of the oxidation, dissolution and modification of Cu surface in slurries at various pH using hydrogen peroxide as oxidizer, glycine as complexing agent and 3-amino-triazol (ATA) as inhibitor during Cu-CMP. The electrochemical process involved in the oxidative dissolution of copper was investigated by potentiodynamic polarization studies. Surface modification of copper was investigated using Xray photoelectron spectroscopy to understand the interaction of Cu-H2O2-glycine-ATA during CMP. In the absence of glycine and ATA, the copper removal rate is found to be high in a slurry with 5% H2O2 at pH 2, then it decreases with increasing pH and reaches the minimum at pH 6, it continuously increases at alkaline condition. In the presence of 0.01M glycine, the removal rate of copper decreases in acidic slurries while increases significantly in alkaline slurries. With the further addition of ATA, the copper removal rate was reduced. However, better surface planarity was obtained. The present investigation enhanced understanding of the mechanism of Cu CMP in the presence of oxidizer, complexing agent and inhibitor for formulation of a highly effective CMP-slurry.

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