디자인 룰 50나노 이하의 메모리 소자 제조 공정 중 구리 화학기계적 연마 공정에서 유기산화제가 연마율 및 평탄도에 미치는 영향 = Effect of organic oxidizers on removal rate and surface roughness in Cu chemical mechanical planarization for memory device beyond 50nm

다국어 초록 (Multilingual Abstract)

The increase of removal rate and surface uniformity of copper (Cu) film in Cu chemical mechanical planarization (CMP) was investigated by controlling the corrosion behavior of the Cu film. Butylamine (BA), ethanolamine (EA), hexylamine (HA) and tert-butylamine (TBA) were used as organic oxidizers of Cu film. The interaction between organic oxidizers and the surface of the Cu film was determined by potentiostatic measurement using a potentiometer and by X-ray photoelectron spectroscopy (XPS). Organic oxidizers decreased the open circuit potential of Cu film, which resulted in thick oxidation layers. Cu CMP slurry with organic oxidizers showed higher removal rate (267.43%) and low within wafer non-uniformity (WIWNU) (78.61%), which resulted from soft Cu2O layers by organic oxidizers.

목차 (Table of Contents)

• 1. Introduction ----------------------------------------- 1
• 2. Theoretical Background ----------------------------- 3
• 2.1. Need for planarization ---------------------------- 3
• 2.2. Degrees of Planarization ------------------------- 4
• 2.3. Methods of Planarization ------------------------- 6
• 2.4. CMP Process ----------------------------------- 7
• 2.5. Mechanical Aspects of CMP --------------------- 12
• 2.6. Chemical mechanical aspects of CMP ----------- 17
• 2.7. Dispersion and Stability of Colloidal Particles in Suspension -- 21
• 2.8. Interparticle Forces and Colloidal Stability -------- 23
• 2.9. Van der Waals Forces --------------------------- 28
• 2.10. Electrostatic Double-Layer Forces -------------- 32
• 2.11. Polymer-Induced Forces ----------------------- 36
• 2.12. Depletion Forces ------------------------------ 41
• 3. Experiment --------------------------------------- 44
• 4. Results and Discussion --------------------------- 46
• 4.1. Potentiodynamic behavior of Cu film ------------- 46
• 4.2. Electrochemical impedance spectroscopy -------- 48
• 4.3. Adhesion force of Cu film ------------------------ 53
• 4.4. X-ray Photoelectron Spectroscopy analysis ------- 55
• 4.5. CMP Field evaluation ---------------------------- 57
• 4.6. Surface roughness after CMP -------------------- 60
• 5. Conclusions -------------------------------------- 62
• References ----------------------------------------- 63
• List of tables ---------------------------------------- 67
• List of figures --------------------------------------- 68
• ABSTRACT ----------------------------------------- 70