The Study of Diffusion Barrier (Ta,Ti)Nx Thin Films

• Main Authors: Chin-Hua Hsieh, 謝進華
• Other Authors: Chiapyng Lee
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/13636596915107457171

碩士 === 國立臺灣科技大學 === 材料科技研究所 === 91 === Abstract This study is to evaluate the feasibility and application of (Ta,Ti)NX thin films as diffusion barriers for Cu/Si multilayered systems. The (Ta,Ti)NX films were deposited by radio frequency reactive sputtering from a TaTi target(at.% 50:50) in N2/Ar gas mixtures. When TaTi films were deposited without nitrogen addition,we observed that the crystalline structure included both α-Ta(BCC) and β-Ti(BCC) phases . In addition,we obtained a local minimum resistivity of 173.3 μΩ-cm at 0.1 N2/Ar flow ratio. Finally, the microcrystalline or amorphous (Ta,Ti)NX thin films were obtained at N2/Ar flow ratios higher than 0.5. The Cu(100nm)/(Ta,Ti)N0.53/Si or Cu(100nm)/TaN0.69(25nm)/Si samples were deposited in situ. We observed that (Ta,Ti)N0.53 and TaN0.69 prevented Cu diffusion after an hour annealing up to 550℃and 800℃,respectively. Finally,we obtained the diffusivity and activation energy of barriers by FPP measurement. The adhesive energy was obtained by measuring the contact angles at the interfaces of Cu particles and different barriers. The adhesive energy was improved at Cu/Ta interface because of Ti addition. In addition to the effect of Ti addition,we also observed that the increase of nitrogen concentration in the barreier film decreased the adhesive energy drastically.