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front-end.md [2026/07/03 16:40] – [Processes] eric.fourboul.extfront-end.md [2026/07/09 21:05] (current) – [Processes] eric.fourboul.ext
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        - water;         - water; 
        - abrasive particles (silica, alumina, ceria, depending on the process);        - abrasive particles (silica, alumina, ceria, depending on the process);
-       - chemical agents to oxidise, complex or selectively etch the material; +       - chemical agents to oxidise, complex or adjust pH; 
 There are three primary types  of CMP: oxide CMP, tungsten CMP, and copper CMP There are three primary types  of CMP: oxide CMP, tungsten CMP, and copper CMP
  
 #### 9.1. Oxide CMP #### 9.1. Oxide CMP
-Oxide CMP defines the electrical isolation geometry between every transistor on a chip.+Oxide CMP is primarily used to flatten dielectric layers. 
 +It is used to: 
 +  * flatten an interlayer dielectric (ILD); 
 +  * STI (Shallow Trench Isolation): after filling the isolation trenches; 
 +  * restoring the surface to a flat state before a new lithography or metallisation step; 
 +  * reducing the topography created by the previous steps. 
 ##### Inputs ##### Inputs
  
-* Silica (SiO2) +  * Silica (SiO2) as abrasive 
-Derived from TEOS (tetraethyl orthosilicate): Si(OCH₂CH₃)₄ or Si(OEt)₄ TEOS forms SiO₂ through simple hydrolysis, releasing ethanol (CH₃CH₂OH) : + Derived from TEOS (tetraethyl orthosilicate): Si(OCH₂CH₃)₄ or Si(OEt)₄ TEOS forms SiO₂ through simple hydrolysis, releasing ethanol (CH₃CH₂OH) : 
-Si(OCH2CH3)4 + 2 H2O → SiO2 + 4 CH3CH2OH+Si(OCH2CH3)4 + 2 H2O → SiO2 + 4 CH3CH2OH 
  
-* Ceria (CeO₂)+  * Ceria (CeO₂)
 Ceria slurries achieve much higher oxide removal rates and superior planarization efficiency, making them preferred for "Shallow Trench Isolation" (STI), i.e. the technique that electrically isolates adjacent transistors.   Ceria slurries achieve much higher oxide removal rates and superior planarization efficiency, making them preferred for "Shallow Trench Isolation" (STI), i.e. the technique that electrically isolates adjacent transistors.  
-* hydroxide ions (OH⁻)+ 
 +  * hydroxide ions (OH⁻) 
 +  * Amoniac (NH3) as pH adjustor 
 +  * Potassium hydroxyde (KOH) as pH adjustor 
  
 ##### Outputs ##### Outputs
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 #### 9.2. Tungsten CMP #### 9.2. Tungsten CMP
 +Tungsten CMP is used to remove excess tungsten after it has filled openings.
 +It is used to:
 +  * form contacts;
 +  * form tungsten-filled vias;
 +  * remove tungsten deposited everywhere except in the required cavities.
 The most widely used approach uses ferric nitrate (Fe(NO₃)₃) or hydrogen peroxide (H₂O₂) as the oxidising agent to convert the tungsten surface to a soft tungsten oxide (WO₃) layer, which is then mechanically removed by the abrasive.  The most widely used approach uses ferric nitrate (Fe(NO₃)₃) or hydrogen peroxide (H₂O₂) as the oxidising agent to convert the tungsten surface to a soft tungsten oxide (WO₃) layer, which is then mechanically removed by the abrasive. 
 ##### Inputs ##### Inputs
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 ##### Outputs ##### Outputs
-* tungsten oxide (WO₃)+  * tungsten oxide (WO₃)
  
 ##### Formula ##### Formula
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 #### 9.3. Copper CMP #### 9.3. Copper CMP
 +Copper CMP is used to form copper interconnections, particularly in Damascene or dual-layer schemes
 +It is used to:
 +  * remove excess copper deposited on the surface;
 +  * leave copper only in the trenches and vias intended for interconnect lines;
 +  * planarise after metallisation.
 The most specific feature of copper CMP slurry is the use of benzotriazole (BTA) as a corrosion inhibitor.  The most specific feature of copper CMP slurry is the use of benzotriazole (BTA) as a corrosion inhibitor. 
 ##### Inputs ##### Inputs
   *  5-Methyl-1H-benzotriazole (C7H7N3)   *  5-Methyl-1H-benzotriazole (C7H7N3)
   * Copper (Cu)   * Copper (Cu)
-  * Silica (SiO2)+  * Silica (SiO2) as abrasive
   * hydrogen peroxide (H₂O₂)    * hydrogen peroxide (H₂O₂) 
   * Tantalum nitride (TaN)   * Tantalum nitride (TaN)
   * Tantalum (Ta)   * Tantalum (Ta)
- +  * Amoniac (NH3) as pH adjustor 
- +  * Sodium hydroxyde (NaOH) as pH adjustor 
-#### 9.1. Planarization +d
-  * Silicon dioxide (SiO2) +
-  * Aluminium oxide (Al2O3) +
-  * Cerium oxide (CeO2) +
-  * Deionized water (DI Water) +
-  * Hydrofluoric acid (HF) +
-  * Sulfuric acid (H2SO4) +
-  * Sodium hydroxide (NaOH) +
-  * Potassium hydroxide (KOH) +
-  * Ammonium hydroxide(NH4OH) +
- +
-##### Formula +
- +
-to add +
 ### Manufacturers ### Manufacturers
   * [Applied Materials](https://www.appliedmaterials.com/eu/en/product-library.html)   * [Applied Materials](https://www.appliedmaterials.com/eu/en/product-library.html)
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   * Chemical Mechanical Planarization, [CMP Process Fundamentals: CMP Tools and Process](https://www.youtube.com/watch?v=2z4lq-Ms_OU) ; [CMP Process Fundamentals: CMP Slurries](https://www.youtube.com/watch?v=lWvvKGkFDfk)   * Chemical Mechanical Planarization, [CMP Process Fundamentals: CMP Tools and Process](https://www.youtube.com/watch?v=2z4lq-Ms_OU) ; [CMP Process Fundamentals: CMP Slurries](https://www.youtube.com/watch?v=lWvvKGkFDfk)
   * [jeez-semicon](https://jeez-semicon.com/fr/blog/copper-cmp-vs-tungsten-cmp-vs-oxide-cmp-full-comparison/)   * [jeez-semicon](https://jeez-semicon.com/fr/blog/copper-cmp-vs-tungsten-cmp-vs-oxide-cmp-full-comparison/)
- 
 ### Sources ### Sources
   * Zantye, P. B., Kumar, A., & Sikder, A. K. (2004). Chemical mechanical planarization for microelectronics applications. Materials Science and Engineering: R: Reports, 45(3-6), 89-220.   * Zantye, P. B., Kumar, A., & Sikder, A. K. (2004). Chemical mechanical planarization for microelectronics applications. Materials Science and Engineering: R: Reports, 45(3-6), 89-220.
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   * Kim, H. J. (2018). Abrasive for chemical mechanical polishing (pp. 183-201). Rijeka: InTech   * Kim, H. J. (2018). Abrasive for chemical mechanical polishing (pp. 183-201). Rijeka: InTech
   * Lee, J., He, S., Song, G., & Hogan Jr, C. J. (2022). Size distribution monitoring for chemical mechanical polishing slurries: An intercomparison of electron microscopy, dynamic light scattering, and differential mobility analysis. Powder Technology, 396, 395-405.   * Lee, J., He, S., Song, G., & Hogan Jr, C. J. (2022). Size distribution monitoring for chemical mechanical polishing slurries: An intercomparison of electron microscopy, dynamic light scattering, and differential mobility analysis. Powder Technology, 396, 395-405.
 +  * XU, Qinzhi, CHEN, Lan, YANG, Fei, et al. Influence of slurry components on copper CMP performance in alkaline slurry. Microelectronic Engineering, 2017, vol. 183, p. 1-11.
 +  * PARK, Seonghyun et LEE, Hyunseop. Electrolytically ionized abrasive-free CMP (EAF-CMP) for copper. Applied Sciences, 2021, vol. 11, no 16, p. 7232.
  
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