This paper explores the planar arrangement feature of the copper interconnects in a view field of several millimeters by the focused ion-beam （FIB） Moire inversion method quantitatively. The curved FIB Moire pattern...This paper explores the planar arrangement feature of the copper interconnects in a view field of several millimeters by the focused ion-beam （FIB） Moire inversion method quantitatively. The curved FIB Moire patterns indicate that the copper interconnects are a series of curves with continuous variations instead of beelines. The control equation set of the copper interconnects central lines is attained through the Moire inversion method. This work can be extended to inspect the structural defects and provide a reliable support for the interconnects structure fabrication.展开更多
Chemical mechanical polishing（CMP） is one of the important machining procedures of multilayered copper interconnection for GLSI, meanwhile polishing slurry is a critical factor for realizing the high polishing perfo...Chemical mechanical polishing（CMP） is one of the important machining procedures of multilayered copper interconnection for GLSI, meanwhile polishing slurry is a critical factor for realizing the high polishing performance such as high planarization efficiency, low surface roughness. The effect of slurry components such as abrasive（colloidal silica）, complexing agent（glycine）, inhibitor（BTA） and oxidizing agent（H_2O_2） on the stability of the novel weakly alkaline slurry of copper interconnection CMP for GLSI was investigated in this paper. First, the synergistic and competitive relationship of them in a peroxide-based weakly alkaline slurry during the copper CMP process was studied and the stability mechanism was put forward. Then 1 wt% colloidal silica, 2.5 wt% glycine,200 ppm BTA, 20 m L/L H_2O_2 had been selected as the appropriate concentration to prepare copper slurry, and using such slurry the copper blanket wafer was polished. From the variations of copper removal rate, root-mean square roughness（Sq） value with the setting time, it indicates that the working-life of the novel weakly alkaline slurry can reach more than 7 days, which satisfies the requirement of microelectronics further development.展开更多
This work focuses on numerical modeling of hydrostatic stress, which is critical to the formation of stress-induced voiding （SIV） in copper damascene interconnects. Using three-dimensional finite element analysis, t...This work focuses on numerical modeling of hydrostatic stress, which is critical to the formation of stress-induced voiding （SIV） in copper damascene interconnects. Using three-dimensional finite element analysis, the distribution of hydrostatic stress is examined in copper interconnects and models are based on the samples, which are fabricated in industry. In addition, hydrostatic stress is studied through the influences of different low-k dielectrics, barrier layers and line widths of copper lines, and the results indicate that hydrostatic stress is strongly dependent on these factors. Hydrostatic stress is highly non-uniform throughout the copper structure and the highest tensile hydrostatic stress exists on the top interface of all the copper lines.展开更多
Copper metal is widely electroplated for microelectronic interconnections such as redistribution layers(RDL),pillar bumps,through silicon vias,etc.With advances of multilayered RDL,via-on-via structures have been deve...Copper metal is widely electroplated for microelectronic interconnections such as redistribution layers(RDL),pillar bumps,through silicon vias,etc.With advances of multilayered RDL,via-on-via structures have been developed for ultrahigh-density any-layer interconnection,which expects superconformal filling of interlayer low aspect-ratio vias jointly with coplanar lines and pads.However,it poses a great challenge to electrodeposition,because current via fill mechanisms are stemming from middle to high aspect-ratio(>0.8)vias and lacking applicability in low aspect-ratio(<0.3)RDL-vias,where via geometry related electric-flow fields coupling must be reconsidered.In the present work,a four-additive strategy has been developed for RDL-vias fill and thoroughly investigated from additive electrochemistry,in situ Raman spectroelectrochemistry,and quantum chemistry perspectives.A novel adsorbate configuration controlled(ACC)electrodeposition mechanism is established that at weak-convection bilateral edges and lower corners,the adsorbate displays a weakly-adsorbing configuration to assist accelerator-governed deposition,whereas at strong-convection center,the adsorbate exhibits a mildlyadsorbing configuration to promote leveler-determined inhibition.Deposit profiles can be tailored from dished,flat to domed,depending on predominance of leveler over accelerator.This study should lay theoretical and practical foundations in design and application of copper electroplating additives of multiple adsorbate configurations to cope with complicated interconnect scenarios.展开更多
Hydrostatic stresses of copper dual-damascene interconnects are calculated by a commercial finite element software in this paper.The analytical work is performed to examine the effects of different low-k(k is permitti...Hydrostatic stresses of copper dual-damascene interconnects are calculated by a commercial finite element software in this paper.The analytical work is performed to examine the effects of different low-k(k is permittivity)dielectrics,barrier layer and aspect ratio of via on hydrostatic stress distribution in the copper interconnects.The results of calculation indicate that the hydrostatic stresses are highly non-uniform throughout the copper interconnects and the highest tensile hydrostatic stress exists on the top interface of lower level interconnect near via.Both the high coefficient of thermal expansion and the low elastic modulus of the low-k dielectrics and barrier layer can decrease the highest hydrostatic stress on the top interface,which can improve the reliability of the copper interconnects.展开更多
Ta/NiFe film is deposited on Si substrate precoated with SiO_2 by magnetron sputtering.SiO_2/Ta interface and Ta_5Si_3 standard sample are investigated by using X-ray photoelectron spectroscopy (XPS) and peak decompos...Ta/NiFe film is deposited on Si substrate precoated with SiO_2 by magnetron sputtering.SiO_2/Ta interface and Ta_5Si_3 standard sample are investigated by using X-ray photoelectron spectroscopy (XPS) and peak decomposition technique.The results show that there is a thermodynamically favorable reaction at the SiO_2/Ta interface:37Ta+15SiO_2=5Ta_5Si_3+6Ta_2O_5.The more stable products Ta_5Si_3 and Ta_2O_5 may be beneficial to stop the diffusion of Cu into SiO_2.展开更多
基金supported by the JSPS Postdoctoral Fellowship for Foreign Researchersthe National Basic Research Program of China ("973" Project) (2010CB631005,2011CB606105)+1 种基金the National Natural Science Foundation of China (11172151,90916010)Specialized Research Fund for the Doctoral Program of Higher Education(20090002110048)
文摘This paper explores the planar arrangement feature of the copper interconnects in a view field of several millimeters by the focused ion-beam （FIB） Moire inversion method quantitatively. The curved FIB Moire patterns indicate that the copper interconnects are a series of curves with continuous variations instead of beelines. The control equation set of the copper interconnects central lines is attained through the Moire inversion method. This work can be extended to inspect the structural defects and provide a reliable support for the interconnects structure fabrication.
基金supported by the Major National Science and Technology Special Projects(No.2016ZX02301003-004-007)the Professional Degree Teaching Case Foundation of Hebei Province,China(No.KCJSZ2017008)+1 种基金the Natural Science Foundation of Hebei Province,China(No.F2015202267)the Natural Science Foundation of Tianjin,China(No.16JCYBJC16100)
文摘Chemical mechanical polishing（CMP） is one of the important machining procedures of multilayered copper interconnection for GLSI, meanwhile polishing slurry is a critical factor for realizing the high polishing performance such as high planarization efficiency, low surface roughness. The effect of slurry components such as abrasive（colloidal silica）, complexing agent（glycine）, inhibitor（BTA） and oxidizing agent（H_2O_2） on the stability of the novel weakly alkaline slurry of copper interconnection CMP for GLSI was investigated in this paper. First, the synergistic and competitive relationship of them in a peroxide-based weakly alkaline slurry during the copper CMP process was studied and the stability mechanism was put forward. Then 1 wt% colloidal silica, 2.5 wt% glycine,200 ppm BTA, 20 m L/L H_2O_2 had been selected as the appropriate concentration to prepare copper slurry, and using such slurry the copper blanket wafer was polished. From the variations of copper removal rate, root-mean square roughness（Sq） value with the setting time, it indicates that the working-life of the novel weakly alkaline slurry can reach more than 7 days, which satisfies the requirement of microelectronics further development.
基金Proiect supported by the National Natural Science Foundation of China(No.50871016).
文摘This work focuses on numerical modeling of hydrostatic stress, which is critical to the formation of stress-induced voiding （SIV） in copper damascene interconnects. Using three-dimensional finite element analysis, the distribution of hydrostatic stress is examined in copper interconnects and models are based on the samples, which are fabricated in industry. In addition, hydrostatic stress is studied through the influences of different low-k dielectrics, barrier layers and line widths of copper lines, and the results indicate that hydrostatic stress is strongly dependent on these factors. Hydrostatic stress is highly non-uniform throughout the copper structure and the highest tensile hydrostatic stress exists on the top interface of all the copper lines.
基金supported by Key-Area Research and Development Program of Guangdong Province(No.2023B0101040002)National Natural Science Foundation of China(Nos.62304143,52303092 and 62274172)Guangdong Basic and Applied Basic Research Fund(No.2022B1515120037).
文摘Copper metal is widely electroplated for microelectronic interconnections such as redistribution layers(RDL),pillar bumps,through silicon vias,etc.With advances of multilayered RDL,via-on-via structures have been developed for ultrahigh-density any-layer interconnection,which expects superconformal filling of interlayer low aspect-ratio vias jointly with coplanar lines and pads.However,it poses a great challenge to electrodeposition,because current via fill mechanisms are stemming from middle to high aspect-ratio(>0.8)vias and lacking applicability in low aspect-ratio(<0.3)RDL-vias,where via geometry related electric-flow fields coupling must be reconsidered.In the present work,a four-additive strategy has been developed for RDL-vias fill and thoroughly investigated from additive electrochemistry,in situ Raman spectroelectrochemistry,and quantum chemistry perspectives.A novel adsorbate configuration controlled(ACC)electrodeposition mechanism is established that at weak-convection bilateral edges and lower corners,the adsorbate displays a weakly-adsorbing configuration to assist accelerator-governed deposition,whereas at strong-convection center,the adsorbate exhibits a mildlyadsorbing configuration to promote leveler-determined inhibition.Deposit profiles can be tailored from dished,flat to domed,depending on predominance of leveler over accelerator.This study should lay theoretical and practical foundations in design and application of copper electroplating additives of multiple adsorbate configurations to cope with complicated interconnect scenarios.
基金the National Natural Science Foundation of China(No.50871016)
文摘Hydrostatic stresses of copper dual-damascene interconnects are calculated by a commercial finite element software in this paper.The analytical work is performed to examine the effects of different low-k(k is permittivity)dielectrics,barrier layer and aspect ratio of via on hydrostatic stress distribution in the copper interconnects.The results of calculation indicate that the hydrostatic stresses are highly non-uniform throughout the copper interconnects and the highest tensile hydrostatic stress exists on the top interface of lower level interconnect near via.Both the high coefficient of thermal expansion and the low elastic modulus of the low-k dielectrics and barrier layer can decrease the highest hydrostatic stress on the top interface,which can improve the reliability of the copper interconnects.
文摘Ta/NiFe film is deposited on Si substrate precoated with SiO_2 by magnetron sputtering.SiO_2/Ta interface and Ta_5Si_3 standard sample are investigated by using X-ray photoelectron spectroscopy (XPS) and peak decomposition technique.The results show that there is a thermodynamically favorable reaction at the SiO_2/Ta interface:37Ta+15SiO_2=5Ta_5Si_3+6Ta_2O_5.The more stable products Ta_5Si_3 and Ta_2O_5 may be beneficial to stop the diffusion of Cu into SiO_2.
