【摘要】 在CF4/Ar的感应耦合等离子体中,用“法拉第筒”式的方法研究了SiO2刻蚀速率与不同离子入射角度之间的关系。在所施加的-20～300V射频偏压范围内,SiO2基片的归一化刻蚀速率(NER)呈现两种情况,当偏压值<100V时,归一化刻蚀速率的大小与基片倾斜角度θ符合余弦曲线规律;当偏压值>100V时,θ在15o～60o范围内,归一化刻蚀速率的大小在大于相应的余弦值,θ>60o时归一化刻蚀速率快速下降,在90o附近SiO2表面出现聚合物沉积。θ<60o时,SiO2的表面刻蚀主要决定于入射离子与基片表面间的能量转换,转换能量的大小深刻地影响着SiO2的刻蚀速率,同时也影响形成于基片表面的碳氟聚合物的去除速率。更多还原

【Abstract】 In a CF4/Ar inductively coupled plasma, the relationships between SiO2 etching rates and the ion incident angles were investigated, where the ion incident angle controlled by using a Faraday cage. The RF bias voltage applied on the SiO2 substrate range from -20V to -300V. Two different cases of normalized etching rate (NER) are observed in the bias voltage region. When the magnitudeof the bias voltage is smaller than 100V, the NER changes following a cosine curve with respect to thesubstrate surface angle θ. When the magnitude of the bias voltage is larger than 100V, the NER deviates to higher values from those given by a cosine curve at ion angles between 15o and 60o, andthen quickly decreases at angles higher than 60o until a net deposition is observed at angles near 90o.Etching of SiO2 at ion angles below 60o are determined by the ion energy transferred to the surface, which affects the SiO2 etching rate and the rate of removal of a fluorocarbon polymer film formed on the substrate surface simultaneously.更多还原