|학술대회||2010년 가을 (11/11 ~ 11/12, 무주리조트)|
|발표분야||B. Nano materials and processing Technology(나노소재기술)|
|제목||Investigation of MnSixOy self-formed diffusion barrier using RF-PEALD (Plasma enhanced atomic layer deposition) of Cu-Mn alloy film.|
|초록||Scaling down of ULSI circuit of CMOS based micro-electronic devices, the micro-electronic devices become more faster and smaller size that are promising property of semiconductor market. However, very narrow line width has some disadvantages. For example, because of narrow line width, deposition of conformal and thin barrier is difficult. Furthermore, proportion of barrier width is large, thus resistance is high. Conventional PVD thin films are not able to gain a good quality and conformal layer.
Therefore, in order to get over these negative effects, deposition of thin layer using ALD is important process. Furthermore, it is essential that copper atomic diffusion into dielectric layer such as SiO2. If copper line is not surrounded by diffusion barrier, it cause the leakage current and devices degradation. There are some possible methods for improving these negative effects.
In this study, copper-manganese alloy layer, is used of Mn(thd)3, MABOC(C14H32N2O2Cu) precursor. Cu-Mn alloy film was deposited on the 24 nm sized trench SiO2/Si bi-layer substrate with good step coverage and high quality film using RF plasma enhanced atomic layer deposition (PEALD). And then Cu-Mn alloy film was annealed for formation of MnSixOy self diffusion barrier.
The thickness of copper seed layer was 4∼5 nm. Copper alloy film was deposited the condition of under 200℃, and feeding time of Cu and Mn precursor were 5 seconds. Purge time of Cu and Mn precursor were 10 seconds. XRD, TEM, I-V, C-V measurement (for testing leakage current and thermal stability) were used to analyze this work. After annealing Mn atoms out-diffusion to SiO2 then MnSixOy diffusion barrier formed conformal layer. Annealing temperature was over 300 ℃ for barrier formation.
With this work, thin barrier layer (4 ~ 5nm) by annealing has good uniformity and good thermal stability. So the barrier properties of annealed MnSixOy film are desirable for copper interconnection.
|저자||한동석, 문대용, 김웅선, 권태석, 박종완|
|키워드||Copper interconnect; Diffusion barrier; PEALD; Thermal stability|