PECVD電漿Arcing之改善研究

Abstract

本論文主要以晶圓廠中ASM PECVD PETEOS 製程發生之實際問題Plasma Arcing 作題目.PECVD Plasma Arcing 會導致沉積之薄膜產生厚度不均勻之結果，因為厚度均勻性太差，導致生產線上之晶片報廢，降低晶圓廠生產良率，也增加設備復機成本。 論文中將研究 Plasma Arcing 發生的主因及改善方法，討論 PECVD RF 之作用原理，Heater Top Plate 受電漿蝕刻離子轟擊,導致陽極膜破損進而導致 Plasma Arcing的作用原理。 論文中也將提出預防RF Plasma Arcing 之方法，並實驗改變各種製程參數如增加 Pre coat二氧化矽或改變陽極膜厚度，改變腔體壓力、 RF 功率等,討論改變參數後對 Arcing 發生頻率的影響，設計新Top Plate ，試驗對Wafer Arcing 之影響。

The thesis is about the investigation of ASM PECVD process plasma arcing issue in the foundry. PECVD plasma arcing problem results in deposition uniformity issue of the film deposition. The bad uniformity of the film causes the in-line wafer scrap and the reduction of the production yield. It increases the cost for recovery of the production machine also.

The thesis talks about the study of plasma arcing root cause and the improvement method, including PECVD RF theory, the ion bombardment of the heater top plate by the plasma etching reaction, and further plasma arcing phenomenon due to the anode damage.

The prevention of RF plasma arcing is also mentioned in this topic. There were experiments done to discuss the effect to arcing frequency by change the process parameters such as adding the SiO2 pre-coat step, changing the anodizing coating film thickness, chamber pressure or RF power