化學機械研磨製程中微刮傷缺陷之改善

Abstract

化學機械研磨(CMP)製程是半導體製程中全面平坦化的主要關鍵技術，利用化學機械研磨的平坦化製程，以確保後續的製程不會因為晶片表面凹凸不平造成之線路位移、薄膜覆蓋能力不佳或曝光顯影製程中對準之偏移，進而影響製程之良率以及元件之穩定性。 本論文主要研究內容是控制化學機械研磨之部分關鍵條件來改善化學機械研磨過程中所形成之微刮傷，以避免微刮傷造成生產中晶圓之電路斷線或短路等缺陷之形成，維持化學機械研磨製程的穩定性；此外，程度較輕微之微刮傷，縱使未造成生產中晶圓之電路斷線或短路等功能性缺失，也會引起晶圓外觀上之瑕疵，造成目檢之不良率升高而降低產品品質。 經由生產過程中所收集之資訊找出生產關鍵因素例如研磨液供應系統，研磨墊、研磨墊修整器與刮傷情形之間的關係，利用實驗計劃法找出最佳控制參數，並且在後續驗證中證實該控制參數之穩定性，以確保控制方式之有效性，降低微刮傷所造成之缺陷，提升產品之良率與元件之可靠度。

The Chemical Mechanical Polishing (CMP) is the key technology to the global planarization in the semiconductor manufacturing process. The Chemical Mechanical Polishing planarization process ensures that the follow-up process will not displacement by the surface uneven, the poor ability of the film coverage, and the exposure to alignment offset of the development process. Thereby affects the yield rate and the process stability of the components.

This thesis is based on controlling the critical part of conditions of the chemical mechanical polishing process in order to improve the formation of the micro scratch in Chemical Mechanical Polishing process. In order to avoid the micro scratch which causes the circuit broken or the short circuit, to maintain the stability of the chemical mechanical polishing process. In addition, the minor degree of micro scratch, even without causing the functional deletion, such as circuit broken or short circuit. It can also cause the defects on the appearance of the wafer, which causes the defective rate increasing, and decrease the quality of the product.

Identify the key factors of production. For example: the relationship between the polishing slurry supply system, a polishing pad, a polishing pad conditioner and micro scratch. Use the planning of the experiment to find the optimal control parameters, and to confirm the stability of the control parameter in a subsequent verification. In order to ensure the effectiveness of the control mode, to lower the defects caused by micro scratch, and to enhance product yield and device reliability.