- 期刊
Growth Kinetics of Copper Chemical Vapor Deposition and Trench Filling without a Seed Layer
銅化學氣相沉積之成長動力學與無種晶層的溝槽填實
摘要
Cu(hfac)(vtms)為前驅物，在有與無碘協助的條件下，研究TiN/SiO2/Si基材表面的化學氣相沉積銅之成長動力學，碘吸附於銅表面增益銅的成長速率，它降低銅膜成長之有效能量障礙，當碘表面濃度為4.2 mol%，銅成長速率增加近十倍，當碘表面濃度增加時，銅沉積能量障礙減少，能量障礙依序排列為16.8（0.0%碘）、9.6（3.6%碘）、8.6 kcal/mol（4.2%碘），由量測不同溫度下迷你小室內膜厚沿中央線深入內部的減少量，估算能障。此外，碘也在初期成長階段扮演重要角色，碘減少成核蘊釀時間，增進銅核的水平成長，因此銅核得以彼此相連接，早先成為薄膜，此早先形成的薄膜，有取代一般銅化學氣相沉積的種晶層功能，通過初期成長後，碘浮於成長中的銅膜表面，令其提升成長速率的作用得以持續，這些對於銅膜成長的有利因素聯合起來，使得在沒有種晶層的圖案化基材上，得以完成無孔隙銅填實溝槽的工作。
關鍵字
無資料並列摘要
The growth kinetics of copper chemical vapor deposition (CVD) on TiN/SiO2/Si substrate were investigated, using Cu(hfac)(vtms) as a precursor with and without iodine assistance. The iodine adsorption on copper enhanced the growth rate and reduced the effective energy barrier. The growth rate increased nearly ten-fold at an iodine surface concentration 4.2 mol%. The rate equation was found to be first order for the Cu(hfac)(vtms) concentration, and the energy barrier decreased as the iodine surface concentration increased. The energy barriers were 16.8 (0.0% I), 9.6 (3.6% I), and 8.6 kcal/mol (4.2% I), as measured based on the reduction in the film thickness along the central line of a mini-chamber at various temperatures. Iodine also played a vital role in the initial growth period; it diminished the incubation time and promoted the horizontal growth of copper nuclei so that they extended and connected with each other to form a flat layer at an earlier stage. The initial flat layer played the role of the seed layer that is usually prepared prior to copper CVD. After the initial growth period, iodine floated out and stayed on the growing copper surface, promoting growth. These beneficial effects enabled void-free copper trench filling to be accomplished on a patterned substrate without a seed layer.