A novel alkaline copper slurry that possesses a relatively high planarization performance is investigated under a low abrasive concentration. Based on the action mechanism of CMP, the feasibility of using one type of ...A novel alkaline copper slurry that possesses a relatively high planarization performance is investigated under a low abrasive concentration. Based on the action mechanism of CMP, the feasibility of using one type of slurry in copper bulk elimination process and residual copper elimination process, with different process parameters, was analyzed. In addition, we investigated the regular change of abrasive concentration effect on cop- per and tantalum removal rate and within wafer non-uniformity （WIWNU） in CMP process. When the abrasive concentration is 3 wt%, in bulk elimination process, the copper removal rate achieves 6125 ~/min, while WIWNU is 3.5%, simultaneously. In residual copper elimination process, the copper removal rate is approximately 2700 A/min, while WIWNU is 2.8%. Nevertheless, the tantalum removal rate is 0 A./min, which indicates that barrier layer isn＇t elinainated in residual copper elimination process. The planarization experimental results show that an excellent planarization performance is obtained with a relatively high copper removal rate in bulk elimination process. Meanwhile, atier residual copper elimination process, the dishing value increased inconspicuously, in a control- lable range, and the wafer surface roughness is only 0.326 nm （sq 〈 1 nm） alter polishing. By comparison, the planarization performance and surface quality of alkaline slurry show almost no major differences with two kinds of commercial acid slurries after polishing. All experimental results are conducive to research and improvement of alkaline slurry in the future.展开更多
To describe the dynamic cracking process of the CLT vertical layer,the correlation between a load-displacement curve,specimen cracking,and planar shear failure mechanism of the CLT were explored.A three-point bending ...To describe the dynamic cracking process of the CLT vertical layer,the correlation between a load-displacement curve,specimen cracking,and planar shear failure mechanism of the CLT were explored.A three-point bending test and an improved planar shear test are used to evaluate the shear performance of the CLT.In this study,the load-displacement curve is recorded,the experimental part is synchronized with the video,the dynamic process of cracking of the vertical layer is observed and analyzed throughout the test.From the load-displacement curve,the image characteristics of the initial cracking and the sudden increase of the cracking of the specimen are summar-ized.The description results of the whole dynamic process of the CLT vertical layer cracking are analyzed by pla-nar shear strength value,cracking phenomenon,and azimuth angle of cracking surface.The main conclusions show that the three-point bending test and the improved plain shear test can be used to test the plain shear strength of the CLT,with a difference of only 5.7%.The original crack and the new crack expansion account for 18.9%and 81.1%of the main cracking surface,respectively.And the vertical layer of the CLT specimen under three-point bending has three cracking morphologies,such as radial shake,ring shake,neither along with the radial shake nor along with the ring shake.The azimuth angle of the cracking surface of the CLT vertical layer under planar shear is quite consistent with the first main plane azimuth of the vertical layer of the CLT specimens under the three-point bending test and the shearing test.The shape in the cracking direction of the left half-span or the right half-span of the vertical layer of the specimen is similar to the Chinese character eight.展开更多
This study reports a new weakly alkaline slurry for copper chemical mechanical planarization （CMP）, it can achieve a high planarization efficiency at a reduced down pressure of 1.0 psi. The slurry is studied through...This study reports a new weakly alkaline slurry for copper chemical mechanical planarization （CMP）, it can achieve a high planarization efficiency at a reduced down pressure of 1.0 psi. The slurry is studied through the polish rate, planarization, copper surface roughness and stability. The copper polishing experiment result shows that the polish rate can reach 10032 A/rain. From the multi-layers copper CMP test, a good result is obtained, that is a big step height （10870 A） that can be eliminated in just 35 s, and the copper root mean square surface roughness （sq） is very low （〈 1 rim）. Apart from this, compared with the alkaline slurry researched before, it has a good progress on stability of copper polishing rate, stable for 12 h at least. All the results presented here are relevant for further developments in the area of copper CMP.展开更多
Three model polythiophenes,PTCBT,PTCFBT and PFTCBT,have been synthesized to investigate the effect of fluorination on photovoltaic performance of polythiothenes.Compared with PTCBT,PFTCBT with F atom on TC unit shows ...Three model polythiophenes,PTCBT,PTCFBT and PFTCBT,have been synthesized to investigate the effect of fluorination on photovoltaic performance of polythiothenes.Compared with PTCBT,PFTCBT with F atom on TC unit shows a narrower optical bandgap(1.79 eV),higher crystallinity,and ideal morphology in the active layer,leading to a higher short-circuit current density(J_(SC))of 11.84 mA/cm^2 and a power conversion efficiency(PCE)of 5.93%.The lock-up function of fluorine enhances polythiophene backbone planarity and molecular packing.展开更多
基金supported by the 02 Major Program of the National Medium–Long Term Science and Technology Development Project of China(No.2009ZX02308)
文摘A novel alkaline copper slurry that possesses a relatively high planarization performance is investigated under a low abrasive concentration. Based on the action mechanism of CMP, the feasibility of using one type of slurry in copper bulk elimination process and residual copper elimination process, with different process parameters, was analyzed. In addition, we investigated the regular change of abrasive concentration effect on cop- per and tantalum removal rate and within wafer non-uniformity （WIWNU） in CMP process. When the abrasive concentration is 3 wt%, in bulk elimination process, the copper removal rate achieves 6125 ~/min, while WIWNU is 3.5%, simultaneously. In residual copper elimination process, the copper removal rate is approximately 2700 A/min, while WIWNU is 2.8%. Nevertheless, the tantalum removal rate is 0 A./min, which indicates that barrier layer isn＇t elinainated in residual copper elimination process. The planarization experimental results show that an excellent planarization performance is obtained with a relatively high copper removal rate in bulk elimination process. Meanwhile, atier residual copper elimination process, the dishing value increased inconspicuously, in a control- lable range, and the wafer surface roughness is only 0.326 nm （sq 〈 1 nm） alter polishing. By comparison, the planarization performance and surface quality of alkaline slurry show almost no major differences with two kinds of commercial acid slurries after polishing. All experimental results are conducive to research and improvement of alkaline slurry in the future.
文摘To describe the dynamic cracking process of the CLT vertical layer,the correlation between a load-displacement curve,specimen cracking,and planar shear failure mechanism of the CLT were explored.A three-point bending test and an improved planar shear test are used to evaluate the shear performance of the CLT.In this study,the load-displacement curve is recorded,the experimental part is synchronized with the video,the dynamic process of cracking of the vertical layer is observed and analyzed throughout the test.From the load-displacement curve,the image characteristics of the initial cracking and the sudden increase of the cracking of the specimen are summar-ized.The description results of the whole dynamic process of the CLT vertical layer cracking are analyzed by pla-nar shear strength value,cracking phenomenon,and azimuth angle of cracking surface.The main conclusions show that the three-point bending test and the improved plain shear test can be used to test the plain shear strength of the CLT,with a difference of only 5.7%.The original crack and the new crack expansion account for 18.9%and 81.1%of the main cracking surface,respectively.And the vertical layer of the CLT specimen under three-point bending has three cracking morphologies,such as radial shake,ring shake,neither along with the radial shake nor along with the ring shake.The azimuth angle of the cracking surface of the CLT vertical layer under planar shear is quite consistent with the first main plane azimuth of the vertical layer of the CLT specimens under the three-point bending test and the shearing test.The shape in the cracking direction of the left half-span or the right half-span of the vertical layer of the specimen is similar to the Chinese character eight.
基金Project supported by the Special Project Items No.2 in National Long-Term Technology Development Plan,China(No.2009ZX02308)the Hebei Natural Science Foundation of China(No.F2012202094)
文摘This study reports a new weakly alkaline slurry for copper chemical mechanical planarization （CMP）, it can achieve a high planarization efficiency at a reduced down pressure of 1.0 psi. The slurry is studied through the polish rate, planarization, copper surface roughness and stability. The copper polishing experiment result shows that the polish rate can reach 10032 A/rain. From the multi-layers copper CMP test, a good result is obtained, that is a big step height （10870 A） that can be eliminated in just 35 s, and the copper root mean square surface roughness （sq） is very low （〈 1 rim）. Apart from this, compared with the alkaline slurry researched before, it has a good progress on stability of copper polishing rate, stable for 12 h at least. All the results presented here are relevant for further developments in the area of copper CMP.
基金supported by the National Natural Science Foundation of China(U1401244,21374025,21372053,21572041,51503050)the Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)+2 种基金State Key Laboratory of Luminescent Materials and Devices(2016-skllmd-05)Youth Association for Promoting Innovation(CAS)Center for Excellence in Nanoscience(CAS)
文摘Three model polythiophenes,PTCBT,PTCFBT and PFTCBT,have been synthesized to investigate the effect of fluorination on photovoltaic performance of polythiothenes.Compared with PTCBT,PFTCBT with F atom on TC unit shows a narrower optical bandgap(1.79 eV),higher crystallinity,and ideal morphology in the active layer,leading to a higher short-circuit current density(J_(SC))of 11.84 mA/cm^2 and a power conversion efficiency(PCE)of 5.93%.The lock-up function of fluorine enhances polythiophene backbone planarity and molecular packing.
